RMC-1/RMC-1L/XMC-2 Owners Thread (Post Firmware v1.10)

[marcl]

May 16, 2022 11:15:14 GMT -5 KeithL said:

I'm going to throw something out here... in the form of an "editorial comment".

I would say that the RMC-1's two-channel performance will compare reasonably against that of ANY DAC... at ANY price.

Let me explain that in detail.

Here are some of the specs on the DAC chip we currently use in the RMC-1, RMC-1L, and XMC-2 (these are typical over several different individual options).
S/N: 120 dB (normal modes); 123 dB (mono mode)
Frequency Response: 0 - 80 kHz +0.1 / -2 dB
THD: 0.0003% (converted from specification which is stated in dB)

As you can see these numbers are ridiculously good...

Now, in a simple two-channel DAC, with no processing or extra features, it is quite possible to deliver performance similar to these numbers.

(We're talking about a product that could reasonably be sold for $300-$500.)

Now, once you start talking about a surround sound processor, there is a LOT more involved.

Among other things your DAC is now sharing its case with several high-performance computers.

This makes things like shielding and power supply isolation much more difficult.

And then there's channel switching and routing.

However, if you check the specifications on a processor like our RMC-1, you will see that the specs are still pretty close in practical terms.

For example, in practical terms, the difference between 0.01% THD and 0.001% THD is nonexistent... because both are FAR below the threshold of audibility.

And a S/N of 120 dB is the difference between the quietest sound a human can hear, in a dead quiet room, and the sound of a jet engine revving at twenty feet.

The thing you need to understand is the difference between a $300 DAC, and a $3,000 DAC, and a $30,000 DAC.

And, quite simply, as you can see from those numbers, the difference is NOT performance.

Some expensive DACs do in fact deliver even better performance... but the improvement is NOT going to be audible.

(And some expensive DACs deliver what can only be described fairly as pretty awful technical performance.)

Some expensive DACs offer more obscure differences, like different filter slopes, or different ringing responses.

And, while these don't actually show up in the "conventional" specifications, some of them MAY actually be audible. 

However, at this point, you must make the distinction between "different" and "better"... and often the more expensive DAC is NOT better.

To be quite blunt, I've actually heard $30k DACs that sound AUDIBLY less accurate than some $500 DACs... and audibly worse than an RMC-1.

And I've heard more than a few that cost over $1000 that I literally wouldn't want to listen to...

(But I guess that someone "just likes the way they sound"... and is willing to pay for it.)

At that level the differences involved are more a matter of personal preference than of "improved performance" or "better accuracy".

Are you paying $2500 more for "better performance" or because the designer chose "filter 14" instead of "filter 17" because he or she preferred the sound?

Or, even worse, are you paying that $2500 for worse technical performance, and a deliberate choice to go with "a house sound" over "accuracy"?

Or are you paying for something like an R2R DAC, not because the DAC sounds better, but because the marketing literature sounds better?

Or are you actually paying $30,000 for that distinction"?

(Bear in mind that, along the way, there are many things in the production chain that have far more influence over what you hear than the DAC anyway.)

Now, to be fair, you might find a two channel DAC that can deliver more accurate sound than the RMC-1 (or the XMC-2).

But you're going to have to look pretty hard to find content where that difference would be audible.

And you can also find a $3k DAC, or a $30k DAC, that delivers LESS accurate sound.

And probably more than a few that you personally don't even like the sound of.

My point in this long and somewhat rambling rant is NOT that you cannot possibly find a DAC that you think sounds better than the RMC-1.

My point is that, if you do, price will have little or nothing to do with it.

Most of the audible differences between DACs are NOT due to fancy designs or expensive technology...

And, more importantly, fancy designs and expensive technology quite often do NOT result in audible benefits...

Magical super expensive cutting edge technology that actually makes a huge audible difference simply is not a real thing...

So, by all means, try a separate DAC, connected to an Analog input, in Reference Stereo mode...

But don't assume it's going to necessarily sound better...

Or that it will sound better to you.

And, incidentally, for two channel, I would go with the USB input over HDMI or even AES/EBU... because the jitter suppression is a tiny bit better...

(But, to be fair, I can't honestly say I can hear the difference.)

May 16, 2022 6:46:39 GMT -5 AntonP said:

Have anyone compared RMC-1 DACs quality in stereo vs 1-2K stereo DACs?
And what connection type to win PC is better - over USB or HDMI or AES (can output AES from PC with Lynx AES16e)?

Great points (as always) ... it comes down to "can you hear it?"  "do you like it?" ... but not "is it objectively better".  A couple other thoughts ...

Toole has said - based on his actual research - that the room has more influence on the sound than all the differences in all the electronic components put together.  And yet some people want to listen to 2-channel without room correction.

And to the point about having a source that is high enough resolution to hear actual objective differences, I struggle with the following .... a poorly recorded source doesn't have the resolution to hear the finest differences in detail;  and an extremely well-recorded source will sound so good, that nearly any system will sound excellent when playing it. 

And then Tool interjects his "circle of confusion" ... that all of these recordings are made by engineers in a room listening to sound reproduced by electronics and speakers ... without a standard as to how those electronics, speakers and rooms must sound.  And then we listen to those recordings in our room, with our electronics and our speakers.

[PaulBe]

May 16, 2022 12:20:05 GMT -5 marcl said:

May 16, 2022 11:15:14 GMT -5 KeithL said:

I'm going to throw something out here... in the form of an "editorial comment".

I would say that the RMC-1's two-channel performance will compare reasonably against that of ANY DAC... at ANY price.

Let me explain that in detail.

Here are some of the specs on the DAC chip we currently use in the RMC-1, RMC-1L, and XMC-2 (these are typical over several different individual options).
S/N: 120 dB (normal modes); 123 dB (mono mode)
Frequency Response: 0 - 80 kHz +0.1 / -2 dB
THD: 0.0003% (converted from specification which is stated in dB)

As you can see these numbers are ridiculously good...

Now, in a simple two-channel DAC, with no processing or extra features, it is quite possible to deliver performance similar to these numbers.

(We're talking about a product that could reasonably be sold for $300-$500.)

Now, once you start talking about a surround sound processor, there is a LOT more involved.

Among other things your DAC is now sharing its case with several high-performance computers.

This makes things like shielding and power supply isolation much more difficult.

And then there's channel switching and routing.

However, if you check the specifications on a processor like our RMC-1, you will see that the specs are still pretty close in practical terms.

For example, in practical terms, the difference between 0.01% THD and 0.001% THD is nonexistent... because both are FAR below the threshold of audibility.

And a S/N of 120 dB is the difference between the quietest sound a human can hear, in a dead quiet room, and the sound of a jet engine revving at twenty feet.

The thing you need to understand is the difference between a $300 DAC, and a $3,000 DAC, and a $30,000 DAC.

And, quite simply, as you can see from those numbers, the difference is NOT performance.

Some expensive DACs do in fact deliver even better performance... but the improvement is NOT going to be audible.

(And some expensive DACs deliver what can only be described fairly as pretty awful technical performance.)

Some expensive DACs offer more obscure differences, like different filter slopes, or different ringing responses.

And, while these don't actually show up in the "conventional" specifications, some of them MAY actually be audible. 

However, at this point, you must make the distinction between "different" and "better"... and often the more expensive DAC is NOT better.

To be quite blunt, I've actually heard $30k DACs that sound AUDIBLY less accurate than some $500 DACs... and audibly worse than an RMC-1.

And I've heard more than a few that cost over $1000 that I literally wouldn't want to listen to...

(But I guess that someone "just likes the way they sound"... and is willing to pay for it.)

At that level the differences involved are more a matter of personal preference than of "improved performance" or "better accuracy".

Are you paying $2500 more for "better performance" or because the designer chose "filter 14" instead of "filter 17" because he or she preferred the sound?

Or, even worse, are you paying that $2500 for worse technical performance, and a deliberate choice to go with "a house sound" over "accuracy"?

Or are you paying for something like an R2R DAC, not because the DAC sounds better, but because the marketing literature sounds better?

Or are you actually paying $30,000 for that distinction"?

(Bear in mind that, along the way, there are many things in the production chain that have far more influence over what you hear than the DAC anyway.)

Now, to be fair, you might find a two channel DAC that can deliver more accurate sound than the RMC-1 (or the XMC-2).

But you're going to have to look pretty hard to find content where that difference would be audible.

And you can also find a $3k DAC, or a $30k DAC, that delivers LESS accurate sound.

And probably more than a few that you personally don't even like the sound of.

My point in this long and somewhat rambling rant is NOT that you cannot possibly find a DAC that you think sounds better than the RMC-1.

My point is that, if you do, price will have little or nothing to do with it.

Most of the audible differences between DACs are NOT due to fancy designs or expensive technology...

And, more importantly, fancy designs and expensive technology quite often do NOT result in audible benefits...

Magical super expensive cutting edge technology that actually makes a huge audible difference simply is not a real thing...

So, by all means, try a separate DAC, connected to an Analog input, in Reference Stereo mode...

But don't assume it's going to necessarily sound better...

Or that it will sound better to you.

And, incidentally, for two channel, I would go with the USB input over HDMI or even AES/EBU... because the jitter suppression is a tiny bit better...

(But, to be fair, I can't honestly say I can hear the difference.)

Great points (as always) ... it comes down to "can you hear it?"  "do you like it?" ... but not "is it objectively better".  A couple other thoughts ...

Toole has said - based on his actual research - that the room has more influence on the sound than all the differences in all the electronic components put together.  And yet some people want to listen to 2-channel without room correction.

And to the point about having a source that is high enough resolution to hear actual objective differences, I struggle with the following .... a poorly recorded source doesn't have the resolution to hear the finest differences in detail;  and an extremely well-recorded source will sound so good, that nearly any system will sound excellent when playing it. 

And then Tool interjects his "circle of confusion" ... that all of these recordings are made by engineers in a room listening to sound reproduced by electronics and speakers ... without a standard as to how those electronics, speakers and rooms must sound.  And then we listen to those recordings in our room, with our electronics and our speakers.

See your text that I put in bold.

Toole did state that improvements in low frequencies can be made, but also said "nothing needs to done above about 300-400 Hz" with a good loudspeaker. His focus on room correction used SFM, Sound Field Management, in the bass, and nothing above the Schroeder transition zone. He also stated "If a high-resolution "corrected" room curve looks superbly smooth, there is a possibility that something inappropriate has been done", and can degrade the sound of a very good loudspeaker. And that the "solution is to find and fix the acoustic problem by physical means. Equalization is not the remedy".

Adding to this, he also said that dipole surrounds are "not ideal designs". You use a number of dipoles.

Summarizing from Toole - "Human nature is such that sometimes simply hearing a difference is enough to believe that there has been an improvement. This is what has allowed so many indifferent loudspeakers and room correction algorithms to exit"... "However it clearly can be good for business".

See Sound Reproduction, Third Edition, pages 371-372, 395, 424, more.

Context and conclusion - room correction should start and probably end with physical means, when used above the Schroeder transition zone.
 

[marcl]

May 16, 2022 16:30:47 GMT -5 PaulBe said:

May 16, 2022 12:20:05 GMT -5 marcl said:

Great points (as always) ... it comes down to "can you hear it?"  "do you like it?" ... but not "is it objectively better".  A couple other thoughts ...

Toole has said - based on his actual research - that the room has more influence on the sound than all the differences in all the electronic components put together.  And yet some people want to listen to 2-channel without room correction.

And to the point about having a source that is high enough resolution to hear actual objective differences, I struggle with the following .... a poorly recorded source doesn't have the resolution to hear the finest differences in detail;  and an extremely well-recorded source will sound so good, that nearly any system will sound excellent when playing it. 

And then Tool interjects his "circle of confusion" ... that all of these recordings are made by engineers in a room listening to sound reproduced by electronics and speakers ... without a standard as to how those electronics, speakers and rooms must sound.  And then we listen to those recordings in our room, with our electronics and our speakers.

See your text that I put in bold.

Your second statement doesn't follow from the first. Toole did state that improvements in low frequencies can be made, but also said "nothing needs to done above about 300-400 Hz" with a good loudspeaker. His focus on room correction used SFM, Sound Field Management, in the bass, and nothing above the Schroeder transition region. He also stated "If a high-resolution "corrected" room curve looks superbly smooth, there is a possibility that something inappropriate has been done", and can degrade the sound of a very good loudspeaker. And that the "solution is to find and fix the acoustic problem by physical means. Equalization is not the remedy".

Adding to this, he also said that dipole surrounds are "not ideal designs". You use a number of dipoles.

Summarizing from Toole - "Human nature is such that sometimes simply hearing a difference is enough to believe that there has been an improvement. This is what has allowed so many indifferent loudspeakers and room correction algorithms to exit"... "However it clearly can be good for business".

See Sound Reproduction, Third Edition, pages 371-372, 395, 424, more.

Context...
 

I'm speaking of Toole's work from the book but also interviews and lectures.  I think what he says holds true, and without disagreeing with the comments regarding EQ above the Schroeder frequency ... in the context in which they were made.  He has said, that the room affects the overall sound more than any variance in the electronics.  That statement stands irrespective of how you correct the room issues (room treatment, DRC etc.), and yes correcting room issues with EQ is applicable mostly below the Schroeder Frequency.  But ... he does not specifically address Dirac - ever - which is not typical EQ, but rather proprietary mixed mode filters in conjunction with impulse response correction.  Toole never addresses this type of room correction.  What he says was valid at the time, in the context in which he spoke ... conventional IIR filter EQ.

Dirac works in a way that is consistent with what Toole says.  Dirac does not attempt to fix non-minimum phase anomalies with EQ.  It ignores narrow peaks and nulls which will be position-dependent.  That's the main reason for doing multiple measurements.  Not to obtain an arithmetic average, but to identify the minimum phase issues and correct them ... while ignoring non-minimum phase issues.

He says dipole surrounds are not appropriate designs.  He speaks of this type of dipole surround which was sold at the time (I had a pair of Polks) for 5.1 systems and intended to make the surround signal less localizable.




These speakers were intended to be placed on either side of the MLP and the drivers were out of phase so you were sitting in the null.  This design is not appropriate for the way surround is done today, and definitely not for Atmos.  My Magnepan dipoles  do not work this way.  They happen to be dipoles, but they are aimed directly at the MLP and behave the same as a conventional speaker in that application.  The back wave is scattered elsewhere in the room and is not a factor in how they work as surround (and Atmos) speakers.

But back to the crux of my comment ... I was focusing on one point:  The room is more significant than the differences between electronics.  If one does not address the room, quibbling over one DAC or another makes no sense.

[autocrat]

My room is big (12m x 6m) and has lots of soft things so in-room correction is not a huge issue. I prefer the sound from my media player with its ESS DAC via analogue to the RMC-1, with reference stereo. The soundstage is more "real" - but it is only good for a fairly narrow listening area. Using Dirac and the internal DAC I can a get it sounding good, but not quite as good, however the listening area is bigger.

There's nothing that particularly annoys me about either method, so in a few weeks I may decide that using Dirac sounds better.

[aswiss]

May 16, 2022 6:46:39 GMT -5 AntonP said:

Have anyone compared RMC-1 DACs quality in stereo vs 1-2K stereo DACs?
And what connection type to win PC is better - over USB or HDMI or AES (can output AES from PC with Lynx AES16e)?

I did never do a compare or blind test between internal and external - but I already had a Streamer/DAC (Cocktail Audio X45) when the RMC-1 arrived.

I did try it sometimes, from my Intel NUC with Roon, and the USB attached. If I didn't already had the other device I could easily live with the Sound of the DAC in the RMC-1.

But last year I upgraded for the Rose Hifi RS150, which is now my Roon Endpoint (due to lack of direct streaming to the RMC-1) and it's connected with XLR to the RMC-1.

In Ref. Stereo, the sound is really what I expected - I'm really happy with it. And beside the sound it's the large Touch Screen which pleases me, and made a separate PC needless.

Its your choice to spend an extra 4500 in a streamer. I would do it again, because its not about measurements its about sound.

I also did a test session with only the Rose and my DR3 AMP, when I was listening to my future speakers. Just amazing.

For me, the standard Stereo does never sounded as good as the Ref. Stereo - maybe due to the lack of DSP. I dont use Dirac either - because I didn't understand how to manage the curves, to get e proper (natural) sound, and as well because I dont have a Sub to integrate.

I bought 2 PSI Audio AVAA C-20 - and all my modes are more or less gone. Expensive of course, but best investment so far in acoustics.

Overall, there is only 1 thing that really is disturbing me - the clicks and pops when switching Tone formats over HDMI.

If this can be fixed - great, if not - I'm already used to it. so I don't wait for the firmware anymore - if it comes, good - if not - so what.

[fbczar]

May 16, 2022 11:15:14 GMT -5 KeithL said:

I'm going to throw something out here... in the form of an "editorial comment".

I would say that the RMC-1's two-channel performance will compare reasonably against that of ANY DAC... at ANY price.

Let me explain that in detail.

Here are some of the specs on the DAC chip we currently use in the RMC-1, RMC-1L, and XMC-2 (these are typical over several different individual options).
S/N: 120 dB (normal modes); 123 dB (mono mode)
Frequency Response: 0 - 80 kHz +0.1 / -2 dB
THD: 0.0003% (converted from specification which is stated in dB)

As you can see these numbers are ridiculously good...

Now, in a simple two-channel DAC, with no processing or extra features, it is quite possible to deliver performance similar to these numbers.

(We're talking about a product that could reasonably be sold for $300-$500.)

Now, once you start talking about a surround sound processor, there is a LOT more involved.

Among other things your DAC is now sharing its case with several high-performance computers.

This makes things like shielding and power supply isolation much more difficult.

And then there's channel switching and routing.

However, if you check the specifications on a processor like our RMC-1, you will see that the specs are still pretty close in practical terms.

For example, in practical terms, the difference between 0.01% THD and 0.001% THD is nonexistent... because both are FAR below the threshold of audibility.

And a S/N of 120 dB is the difference between the quietest sound a human can hear, in a dead quiet room, and the sound of a jet engine revving at twenty feet.

The thing you need to understand is the difference between a $300 DAC, and a $3,000 DAC, and a $30,000 DAC.

And, quite simply, as you can see from those numbers, the difference is NOT performance.

Some expensive DACs do in fact deliver even better performance... but the improvement is NOT going to be audible.

(And some expensive DACs deliver what can only be described fairly as pretty awful technical performance.)

Some expensive DACs offer more obscure differences, like different filter slopes, or different ringing responses.

And, while these don't actually show up in the "conventional" specifications, some of them MAY actually be audible. 

However, at this point, you must make the distinction between "different" and "better"... and often the more expensive DAC is NOT better.

To be quite blunt, I've actually heard $30k DACs that sound AUDIBLY less accurate than some $500 DACs... and audibly worse than an RMC-1.

And I've heard more than a few that cost over $1000 that I literally wouldn't want to listen to...

(But I guess that someone "just likes the way they sound"... and is willing to pay for it.)

At that level the differences involved are more a matter of personal preference than of "improved performance" or "better accuracy".

Are you paying $2500 more for "better performance" or because the designer chose "filter 14" instead of "filter 17" because he or she preferred the sound?

Or, even worse, are you paying that $2500 for worse technical performance, and a deliberate choice to go with "a house sound" over "accuracy"?

Or are you paying for something like an R2R DAC, not because the DAC sounds better, but because the marketing literature sounds better?

Or are you actually paying $30,000 for that distinction"?

(Bear in mind that, along the way, there are many things in the production chain that have far more influence over what you hear than the DAC anyway.)

Now, to be fair, you might find a two channel DAC that can deliver more accurate sound than the RMC-1 (or the XMC-2).

But you're going to have to look pretty hard to find content where that difference would be audible.

And you can also find a $3k DAC, or a $30k DAC, that delivers LESS accurate sound.

And probably more than a few that you personally don't even like the sound of.

My point in this long and somewhat rambling rant is NOT that you cannot possibly find a DAC that you think sounds better than the RMC-1.

My point is that, if you do, price will have little or nothing to do with it.

Most of the audible differences between DACs are NOT due to fancy designs or expensive technology...

And, more importantly, fancy designs and expensive technology quite often do NOT result in audible benefits...

Magical super expensive cutting edge technology that actually makes a huge audible difference simply is not a real thing...

So, by all means, try a separate DAC, connected to an Analog input, in Reference Stereo mode...

But don't assume it's going to necessarily sound better...

Or that it will sound better to you.

And, incidentally, for two channel, I would go with the USB input over HDMI or even AES/EBU... because the jitter suppression is a tiny bit better...

(But, to be fair, I can't honestly say I can hear the difference.)

May 16, 2022 6:46:39 GMT -5 AntonP said:

Have anyone compared RMC-1 DACs quality in stereo vs 1-2K stereo DACs?
And what connection type to win PC is better - over USB or HDMI or AES (can output AES from PC with Lynx AES16e)?

But if you are using an XMC-2 or RMC-1 and Dirac and playing a PCM file with a sample rate above 48Khz you are listening to the Analog to Digital Converters instead of the DACS. I think Emotiva would admit that the Analog to Digital Converters are inferior to the DACS. So, with Dirac, it is likely 16/44.1 or 24/48 files will sound better than 24/96 or 24/192 files. It is a shame.

[fazedout]

May 16, 2022 16:57:17 GMT -5 marcl said:

May 16, 2022 16:30:47 GMT -5 PaulBe said:

See your text that I put in bold.

Your second statement doesn't follow from the first. Toole did state that improvements in low frequencies can be made, but also said "nothing needs to done above about 300-400 Hz" with a good loudspeaker. His focus on room correction used SFM, Sound Field Management, in the bass, and nothing above the Schroeder transition region. He also stated "If a high-resolution "corrected" room curve looks superbly smooth, there is a possibility that something inappropriate has been done", and can degrade the sound of a very good loudspeaker. And that the "solution is to find and fix the acoustic problem by physical means. Equalization is not the remedy".

Adding to this, he also said that dipole surrounds are "not ideal designs". You use a number of dipoles.

Summarizing from Toole - "Human nature is such that sometimes simply hearing a difference is enough to believe that there has been an improvement. This is what has allowed so many indifferent loudspeakers and room correction algorithms to exit"... "However it clearly can be good for business".

See Sound Reproduction, Third Edition, pages 371-372, 395, 424, more.

Context...
 

I'm speaking of Toole's work from the book but also interviews and lectures.  I think what he says holds true, and without disagreeing with the comments regarding EQ above the Schroeder frequency ... in the context in which they were made.  He has said, that the room affects the overall sound more than any variance in the electronics.  That statement stands irrespective of how you correct the room issues (room treatment, DRC etc.), and yes correcting room issues with EQ is applicable mostly below the Schroeder Frequency.  But ... he does not specifically address Dirac - ever - which is not typical EQ, but rather proprietary mixed mode filters in conjunction with impulse response correction.  Toole never addresses this type of room correction.  What he says was valid at the time, in the context in which he spoke ... conventional IIR filter EQ.

Dirac works in a way that is consistent with what Toole says.  Dirac does not attempt to fix non-minimum phase anomalies with EQ.  It ignores narrow peaks and nulls which will be position-dependent.  That's the main reason for doing multiple measurements.  Not to obtain an arithmetic average, but to identify the minimum phase issues and correct them ... while ignoring non-minimum phase issues.

He says dipole surrounds are not appropriate designs.  He speaks of this type of dipole surround which was sold at the time (I had a pair of Polks) for 5.1 systems and intended to make the surround signal less localizable.


<button disabled="" class="c-attachment-insert--linked o-btn--sm">Attachment Deleted</button>

These speakers were intended to be placed on either side of the MLP and the drivers were out of phase so you were sitting in the null.  This design is not appropriate for the way surround is done today, and definitely not for Atmos.  My Magnepan dipoles  do not work this way.  They happen to be dipoles, but they are aimed directly at the MLP and behave the same as a conventional speaker in that application.  The back wave is scattered elsewhere in the room and is not a factor in how they work as surround (and Atmos) speakers.

But back to the crux of my comment ... I was focusing on one point:  The room is more significant than the differences between electronics.  If one does not address the room, quibbling over one DAC or another makes no sense.

Significant, certainly.
If the room is designed and built correctly, it’s true that significantly less correction is required, but for many it’s difficult to ‘retrofit’ or build into existing homes. My room’s dimensioning required only 3 planned and specified ‘acoustic devices’ to a standard ‘soft wall’ treatment, all verified to design parameters through REW assessment by the acoustic designer. 
Another aspect on the DAC side and as noted is the genesis of recordings, where different mics, acoustics, mixers and “engin-ears” are involved. These begin with analogue microphones, but depending on the systems are obviously Analogue to Digital Converted in the process in that chain, be it at preamps, or the mixing console or at the recorder stage. Keith’s reflections on DACs could well apply to the the beginning of the whole process, and who knows what types of ADC  are used. More variables to contend with during critical listening assessments. Not in the Metadata chain AFAIK, yet..

[AntonP]

Thank you for answeres.
New questions:
- so USB is best interface for external digital sources?
- does RMC-1 is limited to 24bit 48KHz due to Dirac?
- does DSD (DoP) work over USB? i used raspberry pi based streamer (with album player) and tried to output DSD (64) to RMC-1 and there was no sound.
- UAC2 - what is it?

[AntonP]

- with usb input i have no Reference Stereo option - why?
- does Reference Stereo mode disables crossovers for fronts (small speakers to large)?

[ttocs]

May 17, 2022 23:28:03 GMT -5 AntonP said:

- with usb input i have no Reference Stereo option - why?
- does Reference Stereo mode disables crossovers for fronts (small speakers to large)?

Reference Stereo will only show up as an option when Fronts are setup as Large.

[KeithL]

Whether Sabre DACs sound significantly distinct or not depends a lot on various implementation details.

That's a technical way of saying that a device that uses them can be designed to sound distinctly different or not.

(Some products that use Sabre DACs sound very much like other high quality DACs; others have a distinct "house sound".)

In general, in devices where this difference has been maximized, Sabre DACs end up "sounding as if the treble in the 11 kHz region is boosted about 1 dB".

They sound as if the "detail" or "sharpness"  of the "acoustic image" has been boosted.

To me the effect is the acoustic equivalent of "sharpening" in Photoshop... "the edges of the sounds seem more distinct".

(It's sort of like you were listening "through a magnifying glass" or "using a brighter light".)

Depending on the content, your other components, and your personal preferences, this can make them sound "more detailed" or "somewhat etched or grainy".

Note that, even in this situation, they will still MEASURE admirably flat, so this is a "psychoacoustic effect" that is somehow related to their filter options.

(It makes sense that, especially in a heavily padded and somewhat "dead" room, this might be pleasing... but I would bet that the RMC-1 is more accurate to the original.)

Odds are that room correction is going to make a bigger difference... although not in exactly the same way.

May 16, 2022 17:03:40 GMT -5 autocrat said:

My room is big (12m x 6m) and has lots of soft things so in-room correction is not a huge issue. I prefer the sound from my media player with its ESS DAC via analogue to the RMC-1, with reference stereo. The soundstage is more "real" - but it is only good for a fairly narrow listening area. Using Dirac and the internal DAC I can a get it sounding good, but not quite as good, however the listening area is bigger.

There's nothing that particularly annoys me about either method, so in a few weeks I may decide that using Dirac sounds better.

[KeithL]

I think you may not fully understand something...

Dirac Live is a form of digital processing... so the output from the Dirac Live processing engine is ALWAYS digital.

Therefore, whenever you use Dirac Live, you are listening to the DACs in the processor, since that digital output must be converted back into analog.

(The ONLY time this isn't true is with an ANALOG source and the processor in REFERENCE STEREO mode.)

However the ONLY time the ANALOG TO DIGITAL CONVERTERS in the processor are used is with ANALOG INPUTS.

(Specifically when, IN ANY MODE OTHER THAN REFERENCE STEREO, the analog input must be converted into a digital signal to enable processing to occur.)

If you input a PCM digital signal, or any other DIGITAL signal, at a sample rate above 48k, into the processor, it will be resampled to 48k for Dirac Live processing...

However that resampling is done PURELY DIGITALLY - it DOES NOT involve the analog-to-digital converters in the processor.

Since that process is digital-in-digital-out it involves neither digital-to-analog nor analog-to-digital conversion.

And, since "down-sampling" is a purely mathematical process, there will be no change in sound quality, other than any that MIGHT exist due to the actual change in sample rate.

Up-sampling, even when done digitally, is somewhat complex, and involves some filtering options that often result in audible differences, but down-sampling does not... at least not if done properly.

And, to be quite fair, I have yet to find a case where a high-res file sounded audible better than an "identical" 44k or 48k version, where the changes could specifically be credited to the difference in sample rate.

I can't say it isn't possible... but I've never heard it demonstrated. There are always "other factors" that make a direct comparison impossible.

You could try taking a file that starts out at a higher sample rate, convert it to a lower sample rate, and then compare both on the RMC-1.

(Make sure to make a "pure simple sample rate conversion" with no other "interesting" options enabled.)

With most proper programs the conversion itself should not create any audible differences... and I would not expect to hear significant audible differences on the RMC-1.

Certain other DACs may sound audibly quite different, for better or worse, because they may use different oversampling ratios or filter choices for different input sample rates.

For anyone who wants to experiment for themselves here's a link to a good FREE sample rate conversion program:

www.voxengo.com/product/r8brain/

You should also check out this site.

It provides LOTs of information showing exactly how good or bad various programs perform when doing a simple sample-rate conversion:

src.infinitewave.ca/

May 16, 2022 21:29:23 GMT -5 fbczar said:

May 16, 2022 11:15:14 GMT -5 KeithL said:

I'm going to throw something out here... in the form of an "editorial comment".

I would say that the RMC-1's two-channel performance will compare reasonably against that of ANY DAC... at ANY price.

Let me explain that in detail.

Here are some of the specs on the DAC chip we currently use in the RMC-1, RMC-1L, and XMC-2 (these are typical over several different individual options).
S/N: 120 dB (normal modes); 123 dB (mono mode)
Frequency Response: 0 - 80 kHz +0.1 / -2 dB
THD: 0.0003% (converted from specification which is stated in dB)

As you can see these numbers are ridiculously good...

Now, in a simple two-channel DAC, with no processing or extra features, it is quite possible to deliver performance similar to these numbers.

(We're talking about a product that could reasonably be sold for $300-$500.)

Now, once you start talking about a surround sound processor, there is a LOT more involved.

Among other things your DAC is now sharing its case with several high-performance computers.

This makes things like shielding and power supply isolation much more difficult.

And then there's channel switching and routing.

However, if you check the specifications on a processor like our RMC-1, you will see that the specs are still pretty close in practical terms.

For example, in practical terms, the difference between 0.01% THD and 0.001% THD is nonexistent... because both are FAR below the threshold of audibility.

And a S/N of 120 dB is the difference between the quietest sound a human can hear, in a dead quiet room, and the sound of a jet engine revving at twenty feet.

The thing you need to understand is the difference between a $300 DAC, and a $3,000 DAC, and a $30,000 DAC.

And, quite simply, as you can see from those numbers, the difference is NOT performance.

Some expensive DACs do in fact deliver even better performance... but the improvement is NOT going to be audible.

(And some expensive DACs deliver what can only be described fairly as pretty awful technical performance.)

Some expensive DACs offer more obscure differences, like different filter slopes, or different ringing responses.

And, while these don't actually show up in the "conventional" specifications, some of them MAY actually be audible. 

However, at this point, you must make the distinction between "different" and "better"... and often the more expensive DAC is NOT better.

To be quite blunt, I've actually heard $30k DACs that sound AUDIBLY less accurate than some $500 DACs... and audibly worse than an RMC-1.

And I've heard more than a few that cost over $1000 that I literally wouldn't want to listen to...

(But I guess that someone "just likes the way they sound"... and is willing to pay for it.)

At that level the differences involved are more a matter of personal preference than of "improved performance" or "better accuracy".

Are you paying $2500 more for "better performance" or because the designer chose "filter 14" instead of "filter 17" because he or she preferred the sound?

Or, even worse, are you paying that $2500 for worse technical performance, and a deliberate choice to go with "a house sound" over "accuracy"?

Or are you paying for something like an R2R DAC, not because the DAC sounds better, but because the marketing literature sounds better?

Or are you actually paying $30,000 for that distinction"?

(Bear in mind that, along the way, there are many things in the production chain that have far more influence over what you hear than the DAC anyway.)

Now, to be fair, you might find a two channel DAC that can deliver more accurate sound than the RMC-1 (or the XMC-2).

But you're going to have to look pretty hard to find content where that difference would be audible.

And you can also find a $3k DAC, or a $30k DAC, that delivers LESS accurate sound.

And probably more than a few that you personally don't even like the sound of.

My point in this long and somewhat rambling rant is NOT that you cannot possibly find a DAC that you think sounds better than the RMC-1.

My point is that, if you do, price will have little or nothing to do with it.

Most of the audible differences between DACs are NOT due to fancy designs or expensive technology...

And, more importantly, fancy designs and expensive technology quite often do NOT result in audible benefits...

Magical super expensive cutting edge technology that actually makes a huge audible difference simply is not a real thing...

So, by all means, try a separate DAC, connected to an Analog input, in Reference Stereo mode...

But don't assume it's going to necessarily sound better...

Or that it will sound better to you.

And, incidentally, for two channel, I would go with the USB input over HDMI or even AES/EBU... because the jitter suppression is a tiny bit better...

(But, to be fair, I can't honestly say I can hear the difference.)

But if you are using an XMC-2 or RMC-1 and Dirac and playing a PCM file with a sample rate above 48Khz you are listening to the Analog to Digital Converters instead of the DACS. I think Emotiva would admit that the Analog to Digital Converters are inferior to the DACS. So, with Dirac, it is likely 16/44.1 or 24/48 files will sound better than 24/96 or 24/192 files. It is a shame.

[fbczar]

May 18, 2022 11:07:20 GMT -5 KeithL said:

I think you may not fully understand something...

Dirac Live is a form of digital processing... so the output from the Dirac Live processing engine is ALWAYS digital.

Therefore, whenever you use Dirac Live, you are listening to the DACs in the processor, since that digital output must be converted back into analog.

(The ONLY time this isn't true is with an ANALOG source and the processor in REFERENCE STEREO mode.)

However the ONLY time the ANALOG TO DIGITAL CONVERTERS in the processor are used is with ANALOG INPUTS.

(Specifically when, IN ANY MODE OTHER THAN REFERENCE STEREO, the analog input must be converted into a digital signal to enable processing to occur.)

If you input a PCM digital signal, or any other DIGITAL signal, at a sample rate above 48k, into the processor, it will be resampled to 48k for Dirac Live processing...

However that resampling is done PURELY DIGITALLY - it DOES NOT involve the analog-to-digital converters in the processor.

Since that process is digital-in-digital-out it involves neither digital-to-analog nor analog-to-digital conversion.

And, since "down-sampling" is a purely mathematical process, there will be no change in sound quality, other than any that MIGHT exist due to the actual change in sample rate.

Up-sampling, even when done digitally, is somewhat complex, and involves some filtering options that often result in audible differences, but down-sampling does not... at least not if done properly.

And, to be quite fair, I have yet to find a case where a high-res file sounded audible better than an "identical" 44k or 48k version, where the changes could specifically be credited to the difference in sample rate.

I can't say it isn't possible... but I've never heard it demonstrated. There are always "other factors" that make a direct comparison impossible.

You could try taking a file that starts out at a higher sample rate, convert it to a lower sample rate, and then compare both on the RMC-1.

(Make sure to make a "pure simple sample rate conversion" with no other "interesting" options enabled.)

With most proper programs the conversion itself should not create any audible differences... and I would not expect to hear significant audible differences on the RMC-1.

Certain other DACs may sound audibly quite different, for better or worse, because they may use different oversampling ratios or filter choices for different input sample rates.

For anyone who wants to experiment for themselves here's a link to a good FREE sample rate conversion program:

www.voxengo.com/product/r8brain/

You should also check out this site.

It provides LOTs of information showing exactly how good or bad various programs perform when doing a simple sample-rate conversion:

src.infinitewave.ca/

May 16, 2022 21:29:23 GMT -5 fbczar said:

But if you are using an XMC-2 or RMC-1 and Dirac and playing a PCM file with a sample rate above 48Khz you are listening to the Analog to Digital Converters instead of the DACS. I think Emotiva would admit that the Analog to Digital Converters are inferior to the DACS. So, with Dirac, it is likely 16/44.1 or 24/48 files will sound better than 24/96 or 24/192 files. It is a shame.the owners

Keith, I always appreciate your thoughtful replies. I stand corrected. However, I think you know that my dissatisfaction with the Dirac sampling rate and the lack of DSD over USB harkens back to the promises made relative to at least a 96/24 Dirac sample rate and the promise in the owner’s manual that DSD over USB would be forthcoming for the XMC-2 and RMC-1. I can definitely tell the difference between a pure DSD file and PCM files and one of the main reasons I bought the XMC-2 was the promise of DSD over USB. I have a significant investment in pure DSD recordings and high resolution PCM. I would like to hear them as intended. I think the XMC-2 is a great processor, but it is not as advertised.

[KeithL]

Just FYI....

DSD-over-PCM (DoP) is still on the roadmap... but it's still behind a few other things.

And, as you know, the XMC-2 and RMC-1 currently do DSD via HDMI.

Which means that you can play both SACD discs and DSD files on universal players like the Oppo... in either PCM or pure DSD.

(You would also be able to do so in a "pure SACD player" that delivers a DSD output over HDMI.)

I assume you also know that DoP is simply a packetized transport for DSD so DSD via DoP has the same limitations as DSD via HDMI.

(You cannot use any sort of processing or room correction with DSD sources.)

 

The sample rate at which we can run the Dirac filters is limited by the processing power in our processor and the efficiency of the filter processing code.

At the time we announced our original expectations we had not yet received the code that processes the Dirac filters (we license that code from Dirac).

As of now, with the current code, the highest sample rate we can support is 48k.

We do still hope to be able to increase that to 96k at some point in the future (but, at this point, I don't know if we will succeed in doing so or not).

May 18, 2022 17:31:35 GMT -5 fbczar said:

May 18, 2022 11:07:20 GMT -5 KeithL said:

I think you may not fully understand something...

Dirac Live is a form of digital processing... so the output from the Dirac Live processing engine is ALWAYS digital.

Therefore, whenever you use Dirac Live, you are listening to the DACs in the processor, since that digital output must be converted back into analog.

(The ONLY time this isn't true is with an ANALOG source and the processor in REFERENCE STEREO mode.)

However the ONLY time the ANALOG TO DIGITAL CONVERTERS in the processor are used is with ANALOG INPUTS.

(Specifically when, IN ANY MODE OTHER THAN REFERENCE STEREO, the analog input must be converted into a digital signal to enable processing to occur.)

If you input a PCM digital signal, or any other DIGITAL signal, at a sample rate above 48k, into the processor, it will be resampled to 48k for Dirac Live processing...

However that resampling is done PURELY DIGITALLY - it DOES NOT involve the analog-to-digital converters in the processor.

Since that process is digital-in-digital-out it involves neither digital-to-analog nor analog-to-digital conversion.

And, since "down-sampling" is a purely mathematical process, there will be no change in sound quality, other than any that MIGHT exist due to the actual change in sample rate.

Up-sampling, even when done digitally, is somewhat complex, and involves some filtering options that often result in audible differences, but down-sampling does not... at least not if done properly.

And, to be quite fair, I have yet to find a case where a high-res file sounded audible better than an "identical" 44k or 48k version, where the changes could specifically be credited to the difference in sample rate.

I can't say it isn't possible... but I've never heard it demonstrated. There are always "other factors" that make a direct comparison impossible.

You could try taking a file that starts out at a higher sample rate, convert it to a lower sample rate, and then compare both on the RMC-1.

(Make sure to make a "pure simple sample rate conversion" with no other "interesting" options enabled.)

With most proper programs the conversion itself should not create any audible differences... and I would not expect to hear significant audible differences on the RMC-1.

Certain other DACs may sound audibly quite different, for better or worse, because they may use different oversampling ratios or filter choices for different input sample rates.

For anyone who wants to experiment for themselves here's a link to a good FREE sample rate conversion program:

www.voxengo.com/product/r8brain/

You should also check out this site.

It provides LOTs of information showing exactly how good or bad various programs perform when doing a simple sample-rate conversion:

src.infinitewave.ca/

Keith, I always appreciate your thoughtful replies. I stand corrected. However, I think you know that my dissatisfaction with the Dirac sampling rate and the lack of DSD over USB harkens back to the promises made relative to at least a 96/24 Dirac sample rate and the promise in the owner’s manual that DSD over USB would be forthcoming for the XMC-2 and RMC-1. I can definitely tell the difference between a pure DSD file and PCM files and one of the main reasons I bought the XMC-2 was the promise of DSD over USB. I have a significant investment in pure DSD recordings and high resolution PCM. I would like to hear them as intended. I think the XMC-2 is a great processor, but it is not as advertised.

[JKCashin]

May 18, 2022 6:54:57 GMT -5 ttocs said:

May 17, 2022 23:28:03 GMT -5 AntonP said:

- with usb input i have no Reference Stereo option - why?
- does Reference Stereo mode disables crossovers for fronts (small speakers to large)?

Reference Stereo will only show up as an option when Fronts are setup as Large.

I have my fronts set to small, and i have Reference Stereo available.

[geebo]

May 18, 2022 21:56:21 GMT -5 JKCashin said:

May 18, 2022 6:54:57 GMT -5 ttocs said:

Reference Stereo will only show up as an option when Fronts are setup as Large.

I have my fronts set to small, and i have Reference Stereo available.

Same here. Reference in effect changes the fronts to large temporarily and until you switch to another sound mode. The Manual even warns of the possibility of using small front speakers and Reference mode because speaker damage might occur when they get the full spectrum fed to them.

"Note: Because Reference Stereo Mode does not include bass management, care should be used
when playing “small” speakers in this mode. Reference Stereo Mode can ONLY be selected
using the “Mode Up/Down” buttons if your front speakers are set to Large, but can be selected
as the current mode in the Main Zone Configuration Menu, and can be configured as the
default mode for an input."

[geebo]

May 18, 2022 6:54:57 GMT -5 ttocs said:

May 17, 2022 23:28:03 GMT -5 AntonP said:

- with usb input i have no Reference Stereo option - why?
- does Reference Stereo mode disables crossovers for fronts (small speakers to large)?

Reference Stereo will only show up as an option when Fronts are setup as Large.

Reference mode can only be selected with the mode up/down buttons if fronts are set to large. If set to small you must highlight Reference mode in the Main menu and the arrow right to check a box and confirming that's what you want to do.

[autocrat]

May 18, 2022 22:19:15 GMT -5 geebo said:

May 18, 2022 6:54:57 GMT -5 ttocs said:

Reference Stereo will only show up as an option when Fronts are setup as Large.

Reference mode can only be selected with the mode up/down buttons if fronts are set to large. If set to small you must highlight Reference mode in the Main menu and the arrow right to check a box and confirming that's what you want to do.

Reference Stereo is also available as a discrete command if you use a Logitech remote. Maybe through the app as well.

[ttocs]

May 18, 2022 22:05:47 GMT -5 geebo said:

May 18, 2022 21:56:21 GMT -5 JKCashin said:

I have my fronts set to small, and i have Reference Stereo available.

Same here. Reference in effect changes the fronts to large temporarily and until you switch to another sound mode. The Manual even warns of the possibility of using small front speakers and Reference mode because speaker damage might occur when they get the full spectrum fed to them.

"Note: Because Reference Stereo Mode does not include bass management, care should be used
when playing “small” speakers in this mode. Reference Stereo Mode can ONLY be selected
using the “Mode Up/Down” buttons if your front speakers are set to Large, but can be selected
as the current mode in the Main Zone Configuration Menu, and can be configured as the
default mode for an input."

Never knew this or tried it before, to try to force Reference Stereo from Main Zone Menu. Cool! I usually go by what's available from Mode Up/Down.

I did know about assigning Modes for Inputs and that some modes which aren't supposed to be possible can be forced, but I stopped doing this because it got in the way of being easily flexible for some audio modes for some disc content - old stuff in Mono for example when I want that sound emanating from the channels I want to use.

Always something new coming along from somewhere.

[danblack]

May 18, 2022 21:28:38 GMT -5 KeithL said:

Just FYI....

DSD-over-PCM (DoP) is still on the roadmap... but it's still behind a few other things.

And, as you know, the XMC-2 and RMC-1 currently do DSD via HDMI.

Which means that you can play both SACD discs and DSD files on universal players like the Oppo... in either PCM or pure DSD.

(You would also be able to do so in a "pure SACD player" that delivers a DSD output over HDMI.)

I assume you also know that DoP is simply a packetized transport for DSD so DSD via DoP has the same limitations as DSD via HDMI.

(You cannot use any sort of processing or room correction with DSD sources.)

 

The sample rate at which we can run the Dirac filters is limited by the processing power in our processor and the efficiency of the filter processing code.

At the time we announced our original expectations we had not yet received the code that processes the Dirac filters (we license that code from Dirac).

As of now, with the current code, the highest sample rate we can support is 48k.

We do still hope to be able to increase that to 96k at some point in the future (but, at this point, I don't know if we will succeed in doing so or not).

May 18, 2022 17:31:35 GMT -5 fbczar said:

Keith, I always appreciate your thoughtful replies. I stand corrected. However, I think you know that my dissatisfaction with the Dirac sampling rate and the lack of DSD over USB harkens back to the promises made relative to at least a 96/24 Dirac sample rate and the promise in the owner’s manual that DSD over USB would be forthcoming for the XMC-2 and RMC-1. I can definitely tell the difference between a pure DSD file and PCM files and one of the main reasons I bought the XMC-2 was the promise of DSD over USB. I have a significant investment in pure DSD recordings and high resolution PCM. I would like to hear them as intended. I think the XMC-2 is a great processor, but it is not as advertised.