RMC-1+ / XMC-2+ The G4 Processors & Trade In — New FAQ P1

[doc1963]

Oct 11, 2024 13:38:56 GMT -5 aswiss said:

...But it adds to the relative poor experience with waiting for promised things, like the Balanced OUT which never made to the market (afaik) or the long times for a good Firmware.

I won't copy your entire post... but I'm confused about what I highlighted (bold) above.

The XMC-2, RMC-1L and the RMC-1 all have 16 balanced "outputs". I assume you meant to call into reference the absence of the expansion module...(?)

[lrobertson]

Oct 11, 2024 13:58:28 GMT -5 doc1963 said:

Oct 11, 2024 13:38:56 GMT -5 aswiss said:

...But it adds to the relative poor experience with waiting for promised things, like the Balanced OUT which never made to the market (afaik) or the long times for a good Firmware.

I won't copy your entire post... but I'm confused about what I highlighted (bold) above.

The XMC-2, RMC-L and the RMC-1 all have 16 balanced "outputs". I assume you meant to call into reference the absence of the expansion module...(?)

I think it's not going out on a limb to say it was the balanced expansion outs.. I don't know what else he could be referring to? Same and only reason I'm not totally embracing this upgrade path yet.

[Lsc]

Oct 11, 2024 11:37:35 GMT -5 PaulBe said:

I explain things very well.

Here is some plain English advice for you - Put your $50K Gotham Subs inside of your L&R - Not on the outside.  Sort of like how they are positioned at the Gotham site.  Space them so the distance between them is 1/2 wavelength of 90 - 120 Hz. Adjust spacing till you hit the sweet spot. You may need to adjust distances from the front wall.  Thank me later.  No payment required.

It's a similar arrangement to what the Pros use in an ATMOS soundstage. It's a similar arrangement to what ttocs uses - and he uses a stack for other benefits.  ttocs

Your Gotham's are also a small stack.

Plain enough for you?

I hope you were kidding with this post. 😬 I never said you didn’t explain things well…I said you can comprehend the technical mumbo jumbo ie all those parts inside the units that you know and what is better or worse or different ways to do whatever etc etc. anyone ever tell you that you don’t know a complement if it smacked you in the face? 😉

My subs are inside of the mains but I’m very restricted in space. Which is why I was hoping for DLBC to help me. It’s the best I can do until I get DLBC or the JL CR-1. The crossover functionality inside the XMC2 is pretty basic. I have an old Theta and those really made my subs sound better…too bad the mids and highs were worse vs the XMC2.

Stack of what? They are just dual subs. I’m not trying to the wave forming…only have 1 person listening to my gear 95% of the time. My wife will watch some Netflix shows with me and she doesn’t care about this stuff (unfortunately).

[KeithL]

OK... I missed the part about "20ish subs"...

I also took a look at Trinnov's description of their "waveforming system"...
(I knew it was their latest and greatest room correction system but I hadn't looked at the details.)

OK... we are now entering "editorial land"...
I've read what they claim... and what their system claims to do... but I have never touched or listened to it.

But... to answer your last question first... 
In the context of something like Dirac Live or DLBC or manual room calibration for subs...
Yes that term, and everything about it, is really just counterproductive and potentially very confusing...
They're looking at the entire situation differently... and their explanation only makes sense in the context of the way they're looking at it.
(It's sort of like looking at a rainbow... and a histogram display... and a readout of the wavelengths of each color frequency... )
(Try explaining to a photographer that the red in his photo isn't at exactly 645nm and you want to fix it.)

I'm going to make a go at explaining the differences...
(But, in order to be brief, I'm going to gloss over lots of details.)

In a normal room, at higher frequencies, sound bounces around... a lot.
And, for example, the wavelength of sound at 1 kHz is about one foot...
This means things like that, if you have the same 1 Khz tone playing from two speakers, you will have places where it cancels itself out and places where it adds...
And, because of the wavelength involved, those places will be on the order of six inches apart.
This means that, if you play that tone from both of your front speakers, and move your head from side to side, it will get louder and quieter every few inches.
That's called "a comb filter effect" and it is the result of you moving your head through spots where the signals add and where they cancel.
And the same thing can happen with only one speaker playing, because the sound from the speaker can interact with its own reflection from the walls and such...
(But, at higher frequencies, with lots of walls and stuff in the room, it tends to sort of average out, and we usually don't notice it in a normal room.)

However, let's say you have a subwoofer, playing a 20 Hz note, which has a wavelength of 50 FEET.
In one sense that wavelength will "fold back on itself" and cause cancellations... (that's a really bad way of saying it but it gets the idea across).
That's a really crude way of explaining what causes "room modes"...
If you're sitting in a spot where the signal cancels out because of its own reflection you get a null... and no bass.
And, if you're sitting in a spot where, because of the distances and dimensions, it adds, you get rocked out of your chair...
And these spots will be different at different frequencies...
And, of course, if you had two (or more) subs, they could also cause cancellations with each other.

HOWEVER, because the wave "doesn't fit in the room" we could also think of it as plain old pressure.
The driver in the sub moves out... the inside of the cabinet gets a tiny bit bigger... and the rest of the room gets a tiny bit smaller...
So, when the driver in the sub moves out, the pressure in the room goes up, and vice versa...

And things get really complicated because in reality it seems to act a little bit like both.
The pressure in the room goes up... but it takes a while for that change to reach our ear... and so on.
This is why, when we use room correction, we're "trying to get the wavefronts from all of the subs to reach us at the same time"...
Or maybe we're "trying to get all of the subs to raise the pressure in the room at the same time and lower it at the same time - as experienced from the MLP"...
Different room correction systems look at one way, or the other, or a little of both...
But the end result is the same.

(This is where you'll see talk about "transition frequencies".)
But, in simple terms, what they're all doing is trying to line up the output from all of the subs to produce a smooth response at the MLP.
(Or, if you've used that "wide" setting, a smooth response, maybe not quite as smooth, but over a larger listening area.)

And, with a LOT of subs, the calculations get a LOT more complicated... but they also sort of average out.

AND NOW FOR SOMETHING COMPLETELY DIFFERENT...

Note that a lot of the complications are due to the fact that sound reflects off things like walls and floors and ceilings.

Most of these issues wouldn't exist if the sub and the listener were sitting in an open field WITHOUT walls and ceilings and such.

(Or if it was possible to make a room with walls that didn't reflect anything - like an anechoic chamber.)

That isn't an option for most of us...

But one alternative would be to put some speakers on the walls... and, if we drove them with just the right signal, we could use them to "eat sound".
If that speaker on the wall is being driven exactly out of phase, when that sound hits it, they will cancel out... so THERE WON'T BE A REFLECTION.
So, in essence, we will have made the wall, and all of the problems due to it, disappear.
Obviously there is a major catch or two here...
For one thing this only works at the spot where we have a speaker on the wall (and to a lesser degree for an area around it)...
And, for another thing, we're going to have to figure out AHEAD OF TIME exactly what to play through it to cancel out the sound that's going to hit it...
Guess what... you now know the basic principle behind Dirac ART... using your speakers to "manage the sound from each other".

Trinnov's "waveforming" thing works on the same sort of idea...

Imagine that your entire front wall was one giant subwoofer...
And imagine that your entire back wall was another giant subwoofer...
And you drive them out of phase...
When the front woofer moves out, it creates a pressure wave, which you hear as lovely smooth bass as it washes past your MLP...
And, when that wave finally hits the back wall, instead of reflecting, that rear sub "eats it"... by cancelling it out.
The end result - at least in theory - would be the same as if you had no back wall...
Just one big sub in the front... and nothing on the other side to cause any nasty and annoying reflections...
Of course there are a few obvious problems... like the fact that nobody has room for a subwoofer that big...
And a smaller issue that there will be some "drag" on the walls... which will "distort" that pressure wave.

Trinnov's solution is to use several smaller subs on the front and back walls...
And, with a lot of fancy calculations, and enough of those little subs, in exactly the right places...
This system can theoretically act like one big sub in the front and one big sub in the rear...
(And the "big sub in the rear" is really "a wall sized active bass trap".)
And their "waveforming technology" is their name for all the fancy calculations needed to make all of those little subs act like one big one.
(The "wave" they're "forming" is that sheet of pressure wave that washes across you as it moves from the front to the back.)

My "editorial comment" on this idea is this:
It sounds like a really cool idea...
But I suspect that it could be VERY complicated in practice...
And that it may require A LOT of knowledge and work to optimize it to work well...
And that this is going to be a LOT worse if you have a room that is even slightly unusual...
And, of course, it's going to require multiple subwoofers, in multiple specific locations, in order to work well at all... 
And, of course, the hardware is going to have to be able to control many aspects of what each sub is doing individually...

But... back to your final question...
The idea of "forming" only really makes sense in the paradigm of creating and directing a specific wave of audio energy...
(And that is really not how other room correction systems look at the goal or the process they use to achieve it.)

Oct 11, 2024 11:47:35 GMT -5 lrobertson said:

Oct 11, 2024 11:08:25 GMT -5 PaulBe said:

At the risk of speaking for KeithL KeithL :

KeithL is not writing in poetic language. He is trying to productively explain a somewhat difficult concept in layman’s language.

Key points in his post:

1. Sound itself is not a series of waves which arrive at our ears in specific shapes...

2. … you are NOT "trying to make pretty waves"... What you're trying to do is to deliver a similar amount of PRESSURE everywhere in the room.

It’s not poetry.  It’s psychoacoustics – physics; acoustics; perception; the ear/brain design and connection.

I distill this into ‘We don’t listen in waveforms’.  See writings and talks by Floyd Toole for a more complete discussion.

Our discussion was in reference to the room with 20ish subs. How do they wire those? Do they throw out the minidsp or utilize it when limited to a theoretical 5 channels? Answer me that and I'll find more use in his response because he brushed past what I was asking and corrected a concept that doesn't answer it. I DO value his opinion and would be curious if the trinnov waveforming or the dirac art developers could make a more valuable case for the laymen like me to understand what they are trying to do. Level it or form it? Does a pressure level in one place interacting with another in another place in specific manner count for forming? Or is the mention of waveforming counterproductive because of the visuals it provides? I do think he'd but heads at Trinnov based on words not concepts.

[lrobertson]

Oct 11, 2024 14:36:06 GMT -5 KeithL said:

OK... I missed the part about "20ish subs"...

I also took a look at Trinnov's description of their "waveforming system"...
(I knew it was their latest and greatest room correction system but I hadn't looked at the details.)

OK... we are now entering "editorial land"...
I've read what they claim... and what their system claims to do... but I have never touched or listened to it.

But... to answer your last question first... 
In the context of something like Dirac Live or DLBC or manual room calibration for subs...
Yes that term, and everything about it, is really just counterproductive and potentially very confusing...
They're looking at the entire situation differently... and their explanation only makes sense in the context of the way they're looking at it.
(It's sort of like looking at a rainbow... and a histogram display... and a readout of the wavelengths of each color frequency... )
(Try explaining to a photographer that the red in his photo isn't at exactly 645nm and you want to fix it.)

I'm going to make a go at explaining the differences...
(But, in order to be brief, I'm going to gloss over lots of details.)

In a normal room, at higher frequencies, sound bounces around... a lot.
And, for example, the wavelength of sound at 1 kHz is about one foot...
This means things like that, if you have the same 1 Khz tone playing from two speakers, you will have places where it cancels itself out and places where it adds...
And, because of the wavelength involved, those places will be on the order of six inches apart.
This means that, if you play that tone from both of your front speakers, and move your head from side to side, it will get louder and quieter every few inches.
That's called "a comb filter effect" and it is the result of you moving your head through spots where the signals add and where they cancel.
And the same thing can happen with only one speaker playing, because the sound from the speaker can interact with its own reflection from the walls and such...
(But, at higher frequencies, with lots of walls and stuff in the room, it tends to sort of average out, and we usually don't notice it in a normal room.)

However, let's say you have a subwoofer, playing a 20 Hz note, which has a wavelength of 50 FEET.
In one sense that wavelength will "fold back on itself" and cause cancellations... (that's a really bad way of saying it but it gets the idea across).
That's a really crude way of explaining what causes "room modes"...
If you're sitting in a spot where the signal cancels out because of its own reflection you get a null... and no bass.
And, if you're sitting in a spot where, because of the distances and dimensions, it adds, you get rocked out of your chair...
And these spots will be different at different frequencies...
And, of course, if you had two (or more) subs, they could also cause cancellations with each other.

HOWEVER, because the wave "doesn't fit in the room" we could also think of it as plain old pressure.
The driver in the sub moves out... the inside of the cabinet gets a tiny bit bigger... and the rest of the room gets a tiny bit smaller...
So, when the driver in the sub moves out, the pressure in the room goes up, and vice versa...

And things get really complicated because in reality it seems to act a little bit like both.
The pressure in the room goes up... but it takes a while for that change to reach our ear... and so on.
This is why, when we use room correction, we're "trying to get the wavefronts from all of the subs to reach us at the same time"...
Or maybe we're "trying to get all of the subs to raise the pressure in the room at the same time and lower it at the same time - as experienced from the MLP"...
Different room correction systems look at one way, or the other, or a little of both...
But the end result is the same.

(This is where you'll see talk about "transition frequencies".)
But, in simple terms, what they're all doing is trying to line up the output from all of the subs to produce a smooth response at the MLP.
(Or, if you've used that "wide" setting, a smooth response, maybe not quite as smooth, but over a larger listening area.)

And, with a LOT of subs, the calculations get a LOT more complicated... but they also sort of average out.

AND NOW FOR SOMETHING COMPLETELY DIFFERENT...

Note that a lot of the complications are due to the fact that sound reflects off things like walls and floors and ceilings.

Most of these issues wouldn't exist if the sub and the listener were sitting in an open field WITHOUT walls and ceilings and such.

(Or if it was possible to make a room with walls that didn't reflect anything - like an anechoic chamber.)

That isn't an option for most of us...

But one alternative would be to put some speakers on the walls... and, if we drove them with just the right signal, we could use them to "eat sound".
If that speaker on the wall is being driven exactly out of phase, when that sound hits it, they will cancel out... so THERE WON'T BE A REFLECTION.
So, in essence, we will have made the wall, and all of the problems due to it, disappear.
Obviously there is a major catch or two here...
For one thing this only works at the spot where we have a speaker on the wall (and to a lesser degree for an area around it)...
And, for another thing, we're going to have to figure out AHEAD OF TIME exactly what to play through it to cancel out the sound that's going to hit it...
Guess what... you now know the basic principle behind Dirac ART... using your speakers to "manage the sound from each other".

Trinnov's "waveforming" thing works on the same sort of idea...

Imagine that your entire front wall was one giant subwoofer...
And imagine that your entire back wall was another giant subwoofer...
And you drive them out of phase...
When the front woofer moves out, it creates a pressure wave, which you hear as lovely smooth bass as it washes past your MLP...
And, when that wave finally hits the back wall, instead of reflecting, that rear sub "eats it"... by cancelling it out.
The end result - at least in theory - would be the same as if you had no back wall...
Just one big sub in the front... and nothing on the other side to cause any nasty and annoying reflections...
Of course there are a few obvious problems... like the fact that nobody has room for a subwoofer that big...
And a smaller issue that there will be some "drag" on the walls... which will "distort" that pressure wave.

Trinnov's solution is to use several smaller subs on the front and back walls...
And, with a lot of fancy calculations, and enough of those little subs, in exactly the right places...
This system can theoretically act like one big sub in the front and one big sub in the rear...
(And the "big sub in the rear" is really "a wall sized active bass trap".)
And their "waveforming technology" is their name for all the fancy calculations needed to make all of those little subs act like one big one.
(The "wave" they're "forming" is that sheet of pressure wave that washes across you as it moves from the front to the back.)

My "editorial comment" on this idea is this:
It sounds like a really cool idea...
But I suspect that it could be VERY complicated in practice...
And that it may require A LOT of knowledge and work to optimize it to work well...
And that this is going to be a LOT worse if you have a room that is even slightly unusual...
And, of course, it's going to require multiple subwoofers, in multiple specific locations, in order to work well at all... 
And, of course, the hardware is going to have to be able to control many aspects of what each sub is doing individually...

But... back to your final question...
The idea of "forming" only really makes sense in the paradigm of creating and directing a specific wave of audio energy...
(And that is really not how other room correction systems look at the goal or the process they use to achieve it.)

Oct 11, 2024 11:47:35 GMT -5 lrobertson said:

Our discussion was in reference to the room with 20ish subs. How do they wire those? Do they throw out the minidsp or utilize it when limited to a theoretical 5 channels? Answer me that and I'll find more use in his response because he brushed past what I was asking and corrected a concept that doesn't answer it. I DO value his opinion and would be curious if the trinnov waveforming or the dirac art developers could make a more valuable case for the laymen like me to understand what they are trying to do. Level it or form it? Does a pressure level in one place interacting with another in another place in specific manner count for forming? Or is the mention of waveforming counterproductive because of the visuals it provides? I do think he'd but heads at Trinnov based on words not concepts.

Thanks for that explanation Keith. I thought I remembered hearing DLBC was conceptually similar to ART in some way but ART takes it further and involves the lower output of full range speakers for more positional cancelation options. Could you theoretically set up DLBC sub arrays similar to a trinnov waveform wall and expect a similar but different flavor? I'm not sure if they allow you to address the theoretical rear array as support subs in dlbc or if that is a role reserved for ART... Or if they would even work as an array as intended without the special sauce.. I've also seen claims that Trinnov can handle 4 cornered ground subs but I'm sure a lot worse results. I wonder if the Trinnov array calcs to create the single wall sub effect is static or dynamic meaning could a minidsp create the automated wall sub and DLBC takes it from there if you follow trinnov placement guidelines.

[PaulBe]

Oct 11, 2024 14:18:24 GMT -5 Lsc said:

Oct 11, 2024 11:37:35 GMT -5 PaulBe said:

I explain things very well.

Here is some plain English advice for you - Put your $50K Gotham Subs inside of your L&R - Not on the outside.  Sort of like how they are positioned at the Gotham site.  Space them so the distance between them is 1/2 wavelength of 90 - 120 Hz. Adjust spacing till you hit the sweet spot. You may need to adjust distances from the front wall.  Thank me later.  No payment required.

It's a similar arrangement to what the Pros use in an ATMOS soundstage. It's a similar arrangement to what ttocs uses - and he uses a stack for other benefits.  ttocs

Your Gotham's are also a small stack.

Plain enough for you?

I hope you were kidding with this post. 😬 I never said you didn’t explain things well…I said you can comprehend the technical mumbo jumbo ie all those parts inside the units that you know and what is better or worse or different ways to do whatever etc etc. anyone ever tell you that you don’t know a complement if it smacked you in the face? 😉

My subs are inside of the mains but I’m very restricted in space. Which is why I was hoping for DLBC to help me. It’s the best I can do until I get DLBC or the JL CR-1. The crossover functionality inside the XMC2 is pretty basic. I have an old Theta and those really made my subs sound better…too bad the mids and highs were worse vs the XMC2.

Stack of what? They are just dual subs. I’m not trying to the wave forming…only have 1 person listening to my gear 95% of the time. My wife will watch some Netflix shows with me and she doesn’t care about this stuff (unfortunately).

Well smack me in the face! I didn't realize that "Lonnie being my favorite. He is probably the worst project estimator because he is always over optimistic on delivery timeframes but he is honest, has a ton of knowledge and can explain things in plain English vs the technical's mumbo jumbo that only folks like PaulBe can understand 😬." was a compliment.  Thanks for the compliment.

I think the JL CR-1 is a questionable cure. Beautiful looking crossover. I love the red Wima MKP capacitors inside. I used a lot of them. Great capacitors, and expensive.  Still have a lot of them.

A I recalled, the last picture I saw of your system had the Subs on the outside of L&R. My mistake.

Each of your dual subwoofers is a vertical 'stack' of 2 woofers.

[Lsc]

Oct 11, 2024 15:04:33 GMT -5 PaulBe said:

Oct 11, 2024 14:18:24 GMT -5 Lsc said:

I hope you were kidding with this post. 😬 I never said you didn’t explain things well…I said you can comprehend the technical mumbo jumbo ie all those parts inside the units that you know and what is better or worse or different ways to do whatever etc etc. anyone ever tell you that you don’t know a complement if it smacked you in the face? 😉

My subs are inside of the mains but I’m very restricted in space. Which is why I was hoping for DLBC to help me. It’s the best I can do until I get DLBC or the JL CR-1. The crossover functionality inside the XMC2 is pretty basic. I have an old Theta and those really made my subs sound better…too bad the mids and highs were worse vs the XMC2.

Stack of what? They are just dual subs. I’m not trying to the wave forming…only have 1 person listening to my gear 95% of the time. My wife will watch some Netflix shows with me and she doesn’t care about this stuff (unfortunately).

Well smack me in the face! I didn't realize that "Lonnie being my favorite. He is probably the worst project estimator because he is always over optimistic on delivery timeframes but he is honest, has a ton of knowledge and can explain things in plain English vs the technical's mumbo jumbo that only folks like PaulBe can understand 😬." was a compliment.  Thanks for the compliment.

I think the JL CR-1 is a questionable cure. Beautiful looking crossover. I love the red Wima MKP capacitors inside. I used a lot of them. Great capacitors, and expensive.  Still have a lot of them.

A I recalled, the last picture I saw of your system had the Subs on the outside of L&R. My mistake.

Each of your dual subwoofers is a vertical 'stack' of 2 woofers.

The JL CR-1 will require a preamp and a DAC to complete the separate 2 channel route. I might be buying one today - same cost (used) as the XMC2+ trade-in.

I’m sure I will also upgrade to the XMC2+ sometime next year but it won’t be as urgent. I’m not going to the RMC-1+ route because I’m running 5.2 in my family room and that’s all that’ll fit in here and not look like a mess.

That’s what I’m talking about lol!”Wima MKP” I always get a kick out of this technical stuff 😬.

[PaulBe]

Oct 11, 2024 15:21:15 GMT -5 Lsc said:

Oct 11, 2024 15:04:33 GMT -5 PaulBe said:

Well smack me in the face! I didn't realize that "Lonnie being my favorite. He is probably the worst project estimator because he is always over optimistic on delivery timeframes but he is honest, has a ton of knowledge and can explain things in plain English vs the technical's mumbo jumbo that only folks like PaulBe can understand 😬." was a compliment.  Thanks for the compliment.

I think the JL CR-1 is a questionable cure. Beautiful looking crossover. I love the red Wima MKP capacitors inside. I used a lot of them. Great capacitors, and expensive.  Still have a lot of them.

A I recalled, the last picture I saw of your system had the Subs on the outside of L&R. My mistake.

Each of your dual subwoofers is a vertical 'stack' of 2 woofers.

The JL CR-1 will require a preamp and a DAC to complete the separate 2 channel route. I might be buying one today - same cost (used) as the XMC2+ trade-in.

I’m sure I will also upgrade to the XMC2+ sometime next year but it won’t be as urgent. I’m not going to the RMC-1+ route because I’m running 5.2 in my family room and that’s all that’ll fit in here and not look like a mess.

That’s what I’m talking about lol!”Wima MKP” I always get a kick out of this technical stuff 😬.

I use a separate stereo electronics stack for 2 channel analog and some digital sources. L&R are full range bi-amped speakers with 15" woofers. I don't care about Subs for these sources.

Higher channel count than what is on a recording is not a holy grail for sound reproduction. Sometimes, less is more. I backed off to 2 Height channels and enjoy the overall reproduction more than when I used 6 height channels. I may try 4 height channels in the future but haven't been willing to spend the money.

Wima:
www.wima.de/en/

[PaulBe]

Oct 11, 2024 14:36:06 GMT -5 KeithL said:

OK... I missed the part about "20ish subs"...

I also took a look at Trinnov's description of their "waveforming system"...
(I knew it was their latest and greatest room correction system but I hadn't looked at the details.)

OK... we are now entering "editorial land"...
I've read what they claim... and what their system claims to do... but I have never touched or listened to it.

But... to answer your last question first... 
In the context of something like Dirac Live or DLBC or manual room calibration for subs...
Yes that term, and everything about it, is really just counterproductive and potentially very confusing...
They're looking at the entire situation differently... and their explanation only makes sense in the context of the way they're looking at it.
(It's sort of like looking at a rainbow... and a histogram display... and a readout of the wavelengths of each color frequency... )
(Try explaining to a photographer that the red in his photo isn't at exactly 645nm and you want to fix it.)

I'm going to make a go at explaining the differences...
(But, in order to be brief, I'm going to gloss over lots of details.)

In a normal room, at higher frequencies, sound bounces around... a lot.
And, for example, the wavelength of sound at 1 kHz is about one foot...
This means things like that, if you have the same 1 Khz tone playing from two speakers, you will have places where it cancels itself out and places where it adds...
And, because of the wavelength involved, those places will be on the order of six inches apart.
This means that, if you play that tone from both of your front speakers, and move your head from side to side, it will get louder and quieter every few inches.
That's called "a comb filter effect" and it is the result of you moving your head through spots where the signals add and where they cancel.
And the same thing can happen with only one speaker playing, because the sound from the speaker can interact with its own reflection from the walls and such...
(But, at higher frequencies, with lots of walls and stuff in the room, it tends to sort of average out, and we usually don't notice it in a normal room.)

However, let's say you have a subwoofer, playing a 20 Hz note, which has a wavelength of 50 FEET.
In one sense that wavelength will "fold back on itself" and cause cancellations... (that's a really bad way of saying it but it gets the idea across).
That's a really crude way of explaining what causes "room modes"...
If you're sitting in a spot where the signal cancels out because of its own reflection you get a null... and no bass.
And, if you're sitting in a spot where, because of the distances and dimensions, it adds, you get rocked out of your chair...
And these spots will be different at different frequencies...
And, of course, if you had two (or more) subs, they could also cause cancellations with each other.

HOWEVER, because the wave "doesn't fit in the room" we could also think of it as plain old pressure.
The driver in the sub moves out... the inside of the cabinet gets a tiny bit bigger... and the rest of the room gets a tiny bit smaller...
So, when the driver in the sub moves out, the pressure in the room goes up, and vice versa...

And things get really complicated because in reality it seems to act a little bit like both.
The pressure in the room goes up... but it takes a while for that change to reach our ear... and so on.
This is why, when we use room correction, we're "trying to get the wavefronts from all of the subs to reach us at the same time"...
Or maybe we're "trying to get all of the subs to raise the pressure in the room at the same time and lower it at the same time - as experienced from the MLP"...
Different room correction systems look at one way, or the other, or a little of both...
But the end result is the same.

(This is where you'll see talk about "transition frequencies".)
But, in simple terms, what they're all doing is trying to line up the output from all of the subs to produce a smooth response at the MLP.
(Or, if you've used that "wide" setting, a smooth response, maybe not quite as smooth, but over a larger listening area.)

And, with a LOT of subs, the calculations get a LOT more complicated... but they also sort of average out.

AND NOW FOR SOMETHING COMPLETELY DIFFERENT...

Note that a lot of the complications are due to the fact that sound reflects off things like walls and floors and ceilings.

Most of these issues wouldn't exist if the sub and the listener were sitting in an open field WITHOUT walls and ceilings and such.

(Or if it was possible to make a room with walls that didn't reflect anything - like an anechoic chamber.)

That isn't an option for most of us...

But one alternative would be to put some speakers on the walls... and, if we drove them with just the right signal, we could use them to "eat sound".
If that speaker on the wall is being driven exactly out of phase, when that sound hits it, they will cancel out... so THERE WON'T BE A REFLECTION.
So, in essence, we will have made the wall, and all of the problems due to it, disappear.
Obviously there is a major catch or two here...
For one thing this only works at the spot where we have a speaker on the wall (and to a lesser degree for an area around it)...
And, for another thing, we're going to have to figure out AHEAD OF TIME exactly what to play through it to cancel out the sound that's going to hit it...
Guess what... you now know the basic principle behind Dirac ART... using your speakers to "manage the sound from each other".

Trinnov's "waveforming" thing works on the same sort of idea...

Imagine that your entire front wall was one giant subwoofer...
And imagine that your entire back wall was another giant subwoofer...
And you drive them out of phase...
When the front woofer moves out, it creates a pressure wave, which you hear as lovely smooth bass as it washes past your MLP...
And, when that wave finally hits the back wall, instead of reflecting, that rear sub "eats it"... by cancelling it out.
The end result - at least in theory - would be the same as if you had no back wall...
Just one big sub in the front... and nothing on the other side to cause any nasty and annoying reflections...
Of course there are a few obvious problems... like the fact that nobody has room for a subwoofer that big...
And a smaller issue that there will be some "drag" on the walls... which will "distort" that pressure wave.

Trinnov's solution is to use several smaller subs on the front and back walls...
And, with a lot of fancy calculations, and enough of those little subs, in exactly the right places...
This system can theoretically act like one big sub in the front and one big sub in the rear...
(And the "big sub in the rear" is really "a wall sized active bass trap".)
And their "waveforming technology" is their name for all the fancy calculations needed to make all of those little subs act like one big one.
(The "wave" they're "forming" is that sheet of pressure wave that washes across you as it moves from the front to the back.)

My "editorial comment" on this idea is this:
It sounds like a really cool idea...
But I suspect that it could be VERY complicated in practice...
And that it may require A LOT of knowledge and work to optimize it to work well...
And that this is going to be a LOT worse if you have a room that is even slightly unusual...
And, of course, it's going to require multiple subwoofers, in multiple specific locations, in order to work well at all... 
And, of course, the hardware is going to have to be able to control many aspects of what each sub is doing individually...

But... back to your final question...
The idea of "forming" only really makes sense in the paradigm of creating and directing a specific wave of audio energy...
(And that is really not how other room correction systems look at the goal or the process they use to achieve it.)

Oct 11, 2024 11:47:35 GMT -5 lrobertson said:

Our discussion was in reference to the room with 20ish subs. How do they wire those? Do they throw out the minidsp or utilize it when limited to a theoretical 5 channels? Answer me that and I'll find more use in his response because he brushed past what I was asking and corrected a concept that doesn't answer it. I DO value his opinion and would be curious if the trinnov waveforming or the dirac art developers could make a more valuable case for the laymen like me to understand what they are trying to do. Level it or form it? Does a pressure level in one place interacting with another in another place in specific manner count for forming? Or is the mention of waveforming counterproductive because of the visuals it provides? I do think he'd but heads at Trinnov based on words not concepts.

FWIW - Trinnov doesn't take credit for the origination of their 'Waveforming' technique. They give credit to the old DBA (double bass array), and state that 'Waveforming' is an extension of DBA.  DBA can be done by anyone with 4 Subs and processing from miniDSP, DBX, a few others... But, the correction is not automated.  We have talked at this forum about some active woofer devices that will do what is necessary at the back wall.  I don't recall the product name.

We need to see what kind of bass management features will be offered on the new + series of Processors... Hint hint...

[Lsc]

Oct 11, 2024 15:42:46 GMT -5 PaulBe said:

FWIW - Trinnov doesn't take credit for the origination of their 'Waveforming' technique. They give credit to the old DBA (double bass array), and state that 'Waveforming' is an extension of DBA.  DBA can be done by anyone with 4 Subs and processing from miniDSP, DBX, a few others... But, the correction is not automated.  We have talked at this forum about some active woofer devices that will do what is necessary at the back wall.  I don't recall the product name.

We need to see what kind of bass management features will be offered on the new + series of Processors... Hint hint...

This brings up an interesting point.

How much of this is DLBC and how much is ART? Is this all ART that we are talking about?

And I need one more F113 (I have one already in the basement game room).

What results are we talking about? That’s the mystery question. To be clear, is it better to have 2 Gothams with no DLBC or ART or is it better to have for example 4 SVS SB2000 subs with ART?

Please feel free to be as technical as you want.

[KeithL]

It is my understanding that Dirac ART is more like the old Dirac Unison...
(It uses some speakers to "actively cancel" sound from others to reduce or control room reflections and other room issues).

It is my understanding that DLBC adds to the functionality of regular Dirac Live by taking the existence of multiple subs into account.
For example, customizing the filter for one sub to enable it to compensate for gaps in the performance of another.
(But their description implies that it uses relatively similar filter choices... just optimized to complement each other rather than to be purely independent.)
Note that DLBC doesn't seem to have any special speaker requirements... while Dirac ART does.

What Trinnov is doing seems to me to be very different...
However Trinnov seems to suggest that there are a variety of options for their system... including some that only use one or two "rear subs".
To me this sounds like there MIGHT potentially be SOME overlap with Dirac ART if you only had three or four subs.
(But then, if you only had one or two rear subs, there would also be some overlap with the idea behind active bass traps like the one made by Bag End.)

Note that, with Trinnov's system, the signals being fed to the rear subs are specifically calculated to ABSORB sound from the front subs.
I don't think there's any way you could convince a miniDSP to make that sort of calculations...
(And the placement is meaningless unless you have the calculations to go with it.)

Oct 11, 2024 14:59:15 GMT -5 lrobertson said:

Oct 11, 2024 14:36:06 GMT -5 KeithL said:

OK... I missed the part about "20ish subs"...

I also took a look at Trinnov's description of their "waveforming system"...
(I knew it was their latest and greatest room correction system but I hadn't looked at the details.)

OK... we are now entering "editorial land"...
I've read what they claim... and what their system claims to do... but I have never touched or listened to it.

..............................

Thanks for that explanation Keith. I thought I remembered hearing DLBC was conceptually similar to ART in some way but ART takes it further and involves the lower output of full range speakers for more positional cancelation options. Could you theoretically set up DLBC sub arrays similar to a trinnov waveform wall and expect a similar but different flavor? I'm not sure if they allow you to address the theoretical rear array as support subs in dlbc or if that is a role reserved for ART... Or if they would even work as an array as intended without the special sauce.. I've also seen claims that Trinnov can handle 4 cornered ground subs but I'm sure a lot worse results. I wonder if the Trinnov array calcs to create the single wall sub effect is static or dynamic meaning could a minidsp create the automated wall sub and DLBC takes it from there if you follow trinnov placement guidelines.

[lrobertson]

Oct 11, 2024 16:16:43 GMT -5 KeithL said:

It is my understanding that Dirac ART is more like the old Dirac Unison...
(It uses some speakers to "actively cancel" sound from others to reduce or control room reflections and other room issues).

It is my understanding that DLBC adds to the functionality of regular Dirac Live by taking the existence of multiple subs into account.
For example, customizing the filter for one sub to enable it to compensate for gaps in the performance of another.
(But their description implies that it uses relatively similar filter choices... just optimized to complement each other rather than to be purely independent.)
Note that DLBC doesn't seem to have any special speaker requirements... while Dirac ART does.

What Trinnov is doing seems to me to be very different...
However Trinnov seems to suggest that there are a variety of options for their system... including some that only use one or two "rear subs".
To me this sounds like there MIGHT potentially be SOME overlap with Dirac ART if you only had three or four subs.
(But then, if you only had one or two rear subs, there would also be some overlap with the idea behind active bass traps like the one made by Bag End.)

Note that, with Trinnov's system, the signals being fed to the rear subs are specifically calculated to ABSORB sound from the front subs.
I don't think there's any way you could convince a miniDSP to make that sort of calculations...
(And the placement is meaningless unless you have the calculations to go with it.)

Oct 11, 2024 14:59:15 GMT -5 lrobertson said:

Thanks for that explanation Keith. I thought I remembered hearing DLBC was conceptually similar to ART in some way but ART takes it further and involves the lower output of full range speakers for more positional cancelation options. Could you theoretically set up DLBC sub arrays similar to a trinnov waveform wall and expect a similar but different flavor? I'm not sure if they allow you to address the theoretical rear array as support subs in dlbc or if that is a role reserved for ART... Or if they would even work as an array as intended without the special sauce.. I've also seen claims that Trinnov can handle 4 cornered ground subs but I'm sure a lot worse results. I wonder if the Trinnov array calcs to create the single wall sub effect is static or dynamic meaning could a minidsp create the automated wall sub and DLBC takes it from there if you follow trinnov placement guidelines.

I did hear that with Trinnov in the infrasonic frequencies the rear subs transform into being an additive force. I believe this is because the room can no longer hold these wavelengths in at a certain point anyways. Or maybe it's just the tradeoff of why focus on canceling frequencies the front wall can barely achieve alone.

Interesting stuff. Thanks Keith

[Lsc]

Oct 11, 2024 15:04:33 GMT -5 PaulBe said:

.
I think the JL CR-1 is a questionable cure. Beautiful looking crossover. I love the red Wima MKP capacitors inside. I used a lot of them. Great capacitors, and expensive.  Still have a lot of them.

Just ended up buying the CR-1. The + model isn’t worth holding out anymore for $2000. I’m estimating about a 1-5% improvement in sound quality (speculation of course). It’s at the end of the list now based on what I get out of it. Once I get my preamp / DAC or a combo unit, then my 2 channel sound will be much improved. Then after I get a new tv that requires hdmi 2.1, I’ll get the + model IF I’m staying with Emotiva.

I agree with you that less is more sometimes (your previous comment on channels). I’m limited by aesthetics in my family room. Can’t have speakers dangling from the ceiling and in-ceilings have limited effect.

[ttocs]

Oct 11, 2024 14:36:06 GMT -5 KeithL said:

My "editorial comment" on this idea is this:
It sounds like a really cool idea...
But I suspect that it could be VERY complicated in practice...
And that it may require A LOT of knowledge and work to optimize it to work well...
And that this is going to be a LOT worse if you have a room that is even slightly unusual...

This is why Trinnov doesn't "allow" WaveForming for every room. They have very specific requirements that need to be followed to be considered to be acceptable for WF.

It took them over a year of "testing" in customer rooms before they stepped up their program of accepting more installs on a customer list. So yes, it's very complex and won't work in a lot of rooms.

Slightly unusual rooms need not apply, they won't be accepted. IOW The Trinnov techs won't tune the room.

[hddave]

Oct 11, 2024 10:14:20 GMT -5 geebo said:

Oct 11, 2024 9:49:04 GMT -5 hddave said:

If you're referring to the price of upgrading the RMC-1 to the RMC-1+, the pricing is actually jumping from $699 to $1500, if they aren't giving original $5000 RMC-1 owners a break anymore.  They stated that the trade-in value for an RMC-1 is $3500 and the RMC-1+ is $5000, resulting in a $1500 difference.

That being said, I am PISSED.  That is more than DOUBLING the previous price for the upgrade, if $5000 RMC-1 owners are expected to pay the same as $3500 RMC-1 owners.  Adding in a phono stage and a balanced stereo input module does absolutely NOTHING for me, so if they're using that to justify the price increase, that isn't going to cut it!  These are readily available for those that WANT or NEED to add these.  That's why they're called "expansion modules".   

Leave me some room for SUBWOOFER expansion modules and then make some.  That's something that almost EVERY RMC-1 owner could probably use.

I haven't complained about the delays.  However, leaving original ($5000) RMC-1 owners hung out to dry is a slap in the face.   We're being asked to pay $6500 for the RMC-1+ while the rest only pay $5000 for the exact same RMC-1+.

So if I bought a new car 5 years ago for $25k and it's trade value is $12k towards a new car that costs $25k does that mean I paid $38k for the new car while first time customers only have to pay $25k for the same new car? The logic doesn't hold up.

You're equating electronics to cars???  How arbitrary and illogical is that???  How about choosing a house for comparison instead?  My house gets wear and tear and the value goes up.  Using your logic with a house as the example, Emotiva should be paying me more for my trade-in than what I paid for it brand new.

NEITHER ONE is a logical comparison.  The price for electronics goes down over time and the features go up while that price goes down, even with inflation.    A Blu-ray player that cost $800 when they first came out can't do what today's $80 Blu-ray player can do.   You can't say that for a car. That's why today's RMC-1 cost $3500 while yesterday's cost was $5000.

Emotiva clearly recognized that $5000 RMC-1 owners shouldn't pay a total of $6500 for an RMC-1+ while $3500 RMC-1+ owners pay a total of $5000.  If they didn't recognize that, they would never have come up with two different pricing tiers in the first place.  Do I think $5000 RMC-1 owners should get a free upgrade so that we both end up with the same RMC-1+ for the same price?  NO!  Do I think splitting the difference was a fair compromise?  YES.

Personally, I don't have any 8K or VRR sources.  I don't need another set of XLR inputs or phono inputs.  I was hoping the upgrade would make better use of my 9.1.6 system with Enhanced Dolby Atmos to make better use of the Wide channels (and/or possibly better use of the top channels?).  Maybe a better chance of compatibility for future subwoofer output expansion modules (not advertised, just wishful thinking)?  I've only got one output available for a subwoofer in my current configuration.  At $699, I was DEFINITELY upgrading to the RMC-1+.  Especially with them sending the new unit before trading in the old unit so I'm never without a processor (that's INSANELY thoughtful of them). At $1500, the value currently is not there for me.  If, someday, they get subwoofer expansion modules (and I haven't already bought a MiniDSP to address the limited subwoofer outputs available in my configuration) and the upgrade path remains the same, $1500 could be worth it.

[aswiss]

Oct 11, 2024 13:58:28 GMT -5 doc1963 said:

Oct 11, 2024 13:38:56 GMT -5 aswiss said:

...But it adds to the relative poor experience with waiting for promised things, like the Balanced OUT which never made to the market (afaik) or the long times for a good Firmware.

I won't copy your entire post... but I'm confused about what I highlighted (bold) above.

The XMC-2, RMC-1L and the RMC-1 all have 16 balanced "outputs". I assume you meant to call into reference the absence of the expansion module...(?)

Yep - that's what I meant. But maybe we are lucky, and they really bring those out at the same time as the + models. That would be nice for those who look for more SUB Outs.

*update* I precised it now in my post.

[PaulBe]

Oct 11, 2024 16:07:05 GMT -5 Lsc said:

Oct 11, 2024 15:42:46 GMT -5 PaulBe said:

FWIW - Trinnov doesn't take credit for the origination of their 'Waveforming' technique. They give credit to the old DBA (double bass array), and state that 'Waveforming' is an extension of DBA.  DBA can be done by anyone with 4 Subs and processing from miniDSP, DBX, a few others... But, the correction is not automated.  We have talked at this forum about some active woofer devices that will do what is necessary at the back wall.  I don't recall the product name.

We need to see what kind of bass management features will be offered on the new + series of Processors... Hint hint...

This brings up an interesting point.

How much of this is DLBC and how much is ART? Is this all ART that we are talking about?

And I need one more F113 (I have one already in the basement game room).

What results are we talking about? That’s the mystery question. To be clear, is it better to have 2 Gothams with no DLBC or ART or is it better to have for example 4 SVS SB2000 subs with ART?

Please feel free to be as technical as you want.

I have never used Dirac Live, DLBC, or ART.  Art requires use of surrounds for correction.  I am looking forward to trying Dirac Live and DLBC with the RMC-1+. I have no interest in ART.  I haven't used Trinnov 'Waveforming'.  I do use DBX AutoEQ for my whole system - including the Subs.  I have amps, Subs, and DBX speaker processors to experiment with DBA (poor mans Waveforming), and use DBX AutoEQ - I've been lazy. 

Anytime you want to give me your Gothams and switch to SVS, it's alright with me. 
However, I will not replace my homemade, closed box, Stereo Integrity SI24mkII, Subs with anything else.

[geebo]

Oct 11, 2024 18:17:59 GMT -5 hddave said:

Oct 11, 2024 10:14:20 GMT -5 geebo said:

So if I bought a new car 5 years ago for $25k and it's trade value is $12k towards a new car that costs $25k does that mean I paid $38k for the new car while first time customers only have to pay $25k for the same new car? The logic doesn't hold up.

You're equating electronics to cars???  How arbitrary and illogical is that???  How about choosing a house for comparison instead?  My house gets wear and tear and the value goes up.  Using your logic with a house as the example, Emotiva should be paying me more for my trade-in than what I paid for it brand new.

NEITHER ONE is a logical comparison.  The price for electronics goes down over time and the features go up while that price goes down, even with inflation.    A Blu-ray player that cost $800 when they first came out can't do what today's $80 Blu-ray player can do.   You can't say that for a car. That's why today's RMC-1 cost $3500 while yesterday's cost was $5000.

Emotiva clearly recognized that $5000 RMC-1 owners shouldn't pay a total of $6500 for an RMC-1+ while $3500 RMC-1+ owners pay a total of $5000.  If they didn't recognize that, they would never have come up with two different pricing tiers in the first place.  Do I think $5000 RMC-1 owners should get a free upgrade so that we both end up with the same RMC-1+ for the same price?  NO!  Do I think splitting the difference was a fair compromise?  YES.

Personally, I don't have any 8K or VRR sources.  I don't need another set of XLR inputs or phono inputs.  I was hoping the upgrade would make better use of my 9.1.6 system with Enhanced Dolby Atmos to make better use of the Wide channels (and/or possibly better use of the top channels?).  Maybe a better chance of compatibility for future subwoofer output expansion modules (not advertised, just wishful thinking)?  I've only got one output available for a subwoofer in my current configuration.  At $699, I was DEFINITELY upgrading to the RMC-1+.  Especially with them sending the new unit before trading in the old unit so I'm never without a processor (that's INSANELY thoughtful of them). At $1500, the value currently is not there for me.  If, someday, they get subwoofer expansion modules (and I haven't already bought a MiniDSP to address the limited subwoofer outputs available in my configuration) and the upgrade path remains the same, $1500 could be worth it.

Ok, so what if you sold your 5 year old TV that you paid $3K for and got $1K that you put towards a new $3k TV? Does that mean you paid $5k for the same TV someone can buy for $3k? I think that's what you're suggesting?

Whether or not the value to you is worth upgrading or not is completely up to you. That's your decision to make. In my opinion (and that's worth what you paid for it) is that $1.5k for the upgrade and new warranty is very generous and one I'll take advantage of as soon as it's available. But that's me.

[hddave]

Oct 11, 2024 19:19:26 GMT -5 geebo said:

Oct 11, 2024 18:17:59 GMT -5 hddave said:

You're equating electronics to cars???  How arbitrary and illogical is that???  How about choosing a house for comparison instead?  My house gets wear and tear and the value goes up.  Using your logic with a house as the example, Emotiva should be paying me more for my trade-in than what I paid for it brand new.

NEITHER ONE is a logical comparison.  The price for electronics goes down over time and the features go up while that price goes down, even with inflation.    A Blu-ray player that cost $800 when they first came out can't do what today's $80 Blu-ray player can do.   You can't say that for a car. That's why today's RMC-1 cost $3500 while yesterday's cost was $5000.

Emotiva clearly recognized that $5000 RMC-1 owners shouldn't pay a total of $6500 for an RMC-1+ while $3500 RMC-1+ owners pay a total of $5000.  If they didn't recognize that, they would never have come up with two different pricing tiers in the first place.  Do I think $5000 RMC-1 owners should get a free upgrade so that we both end up with the same RMC-1+ for the same price?  NO!  Do I think splitting the difference was a fair compromise?  YES.

Personally, I don't have any 8K or VRR sources.  I don't need another set of XLR inputs or phono inputs.  I was hoping the upgrade would make better use of my 9.1.6 system with Enhanced Dolby Atmos to make better use of the Wide channels (and/or possibly better use of the top channels?).  Maybe a better chance of compatibility for future subwoofer output expansion modules (not advertised, just wishful thinking)?  I've only got one output available for a subwoofer in my current configuration.  At $699, I was DEFINITELY upgrading to the RMC-1+.  Especially with them sending the new unit before trading in the old unit so I'm never without a processor (that's INSANELY thoughtful of them). At $1500, the value currently is not there for me.  If, someday, they get subwoofer expansion modules (and I haven't already bought a MiniDSP to address the limited subwoofer outputs available in my configuration) and the upgrade path remains the same, $1500 could be worth it.

Ok, so what if you sold your 5 year old TV that you paid $3K for and got $1K that you put towards a new $3k TV? Does that mean you paid $5k for the same TV someone can buy for $3k? I think that's what you're suggesting?

Whether or not the value to you is worth upgrading or not is completely up to you. That's your decision to make. In my opinion (and that's worth what you paid for it) is that $1.5k for the upgrade and new warranty is very generous and one I'll take advantage of as soon as it's available. But that's me.

You can give "what if" scenarios all day.  Normal depreciation logic does not work in electronics when the new item is often better and cheaper.  You could buy a TV for $1K today that would probably be as good or better than the TV you paid $3K for 5 years ago.  Trust me, I've been there.  

That's not the point anyway.  The point is that Emotiva clearly recognized that it would be more fair to offset SOME of the added cost and planned to do just that.  Now they're not doing that any more.  Seems like a logical progression for someone to rather pay $699 for something instead of $1500 for the exact same thing.  Shouldn't need any more "what if" scenarios to follow that logic, but that's me.

[ttocs]

Oct 11, 2024 20:12:18 GMT -5 hddave said:

Seems like a logical progression for someone to rather pay $699 for something instead of $1500 for the exact same thing.

The + processor offering for $699 is not exactly like the current offering. They differ in at least several ways.

You may lookup these differences by reviewing this thread and the Official Emofest Notes by KlineMJ thread from over the last week, and viewing the official podcast from yesterday.