Emo Mono blocks or XPA-2 gen 3

[Gary Cook]

Sept 27, 2017 19:40:37 GMT -5 leonski said:

More power is higher voltage and less time above that voltage TO recharge. Think sinewave.
I suppose that's where your higher capacitance comes in, but at some point, you'll not be able to 'recharge' it.
Than why would ANY amp need a 20 amp service? Why do the very highest power 7 channel HT amps Require 2x15amp service?
Simply adding capacitance sounds cheaper than adding a larger transformer. 10watts continuous / 100 watt peaks is 'only' 10db.
10watts continuous and 1000 watts peak is still only 20db. FEW amps are capable of that. And few speakers, for that matter.
Maybe 1 watt continuous (those RF-7II speakers are 100db sensitive, after all) and 100 watt peaks is STILL 20db crest factor.
Add another 100 watts to 200 watt peaks total, and that's only another 3db.
maybe score 1 for more sensitive speakers rather than contining to toss inexpensive watts at it?

Let me try another tact, given equal efficiency a 600 watt amplifier running at 250 watts won't need any more power than a 300 watt amplifier running at 250 watts. But the 600 watt amplifier at 250 watts will in general have more capacitance available to handle transients (without "clip). Plus, being an XPR-2 in this case, it will definitely sound better because it is a better quality amp, plus it will probably sound even better because it won't be operating at anywhere near it's limit.

Rather than have a Porsche hobbling around on 4 space-saver spares, why not a lesser sports car on real tires?

If we want to continue with the Porsche analogy, it would be more like me telling the refueler to fill the 120 litre tank up for a 20 lap race when it only needs 60 litres for that race length.




Cheers
Gary

[leonski]

Sept 27, 2017 20:55:07 GMT -5 AudioHTIT said:

I tend to agree with Gary, just because you can’t drive the higher power amp to full output doesn’t mean it won’t deliver as much or more clean power than lower power amp given the same mains. The OP should not dismiss the XPR because he lacks a 20A mains, it may likely still be the best sounding amplifier regardless of whether it’s on a 15 or 20A circuit. I would be more concerned with its massive weight making it difficult for one person to move (my XPA-7 has a similar handicap), and possible shipping costs.

That's true.   Than WHY buy the big power amp which 'theoretically' asks for a 20 amp circuit?

If you need whatever the lower power amp does, WHY buy more?    The OP has 100 db sensitive speakers, for Pete's sake.   125 a side will reproduce an F-35 hovering outside your window-type levels (just heard one last weekend at Miramar, so I've got SOME idea how loud they are in hover!)

Or Pile on the Capacitors and put a current surge limiter on the power line so when you start the amp you don't pop the breaker for the house?

Any idea what happens to a 115v /15a line when you start asking for LOTS of current?    Voltage drops like a stone.    Testers of (mainly) high power amps always
include a VARIAC in their kit so they can at least test at a constant line voltage.   The difference in line stiffness between a 15 and 20 amp service, in this application may be
the difference it takes.   I suspect distortion products rise drastically at some point in power line sag.     I have no real data on this.

And why NOT build an amp with a hugely UnRegulated PS so you get maybe 100 a side 'continuous' with 6db peaks of 400 watts?    

It is also vaguely possible for the Lower powered amp to have higher dynamic headroom than the high powered amp.   For very few amps, except the most HIGHLY 
regulated PS versions is the 'RMS Power' IT.   Even my modest Parasounds have some wacky high CURRENT claim while also claiming about a 1.5db dynamic headroom.
This works out to about 170 watts vs 125 continuous.    No time frame mentioned.

We will apparently NOT be able to convince one-another.    I also don't know that we made the best possible cases for our respective positions.  
Enjoy your Hernia Inducing hobbled amps.     I suspect we'd ALL be surprised at how much power we really Do Not Use!     

I know I'm running 400 per speaker (2x200) for a total of 800 watts (4ohm) and low cutting the main speakers, saving 5% to 10% power and letting the sub do the rest.
If I ever go to a line level crossover, I'll net an additional 2+db headroom.   Which with my horribly low sensitivity panels, will help.    And have audible benefits when not pushing it.  

[rbk123]

Sept 27, 2017 23:12:49 GMT -5 leonski said:

That's true.   Than WHY buy the big power amp which 'theoretically' asks for a 20 amp circuit?

Like Audioh said - because it is the better sounding amp regardless of 15A or 20A circuit. You buy an amp for it's sound, not for it's spec. If a 2W amp sounds better than a 2000W amp, in someone's use case, they go with the one that sounds better. If the 4000W XYZPR sounds better than a 200W Macintosh, you get the 4000W XYZPR even though you don't need the wattage.

[KeithL]

The thing most people tend to forget is that music is dynamic. With typical music, the average level is somewhere between 1/10 and 1/20 of the peak level. (If you decide to play Bach organ music, which isn't all that dynamic, at full power, you might manage to pop a breaker... but most of that power will be drawn by your sub.) Without going into a lot of numbers, the bottom line is that I can't honestly remember when I've heard of someone actually popping a circuit breaker by turning their home theater system up too loud. One of our big 5-channel or 7-channel amps, which could easily draw over 20 amps on the test bench, will more typically use 5-7 amps when playing music as loud as any sane person would want to, and we've got lots of people running two of them off a single circuit with no problems.

A switch mode power supply is more efficient. However, even a linear power supply, of the type used in a big power amp, is actually already quite efficient. Here's the thing.......

Most power amps, including our XPA Gen2 amps, use an unregulated linear power supply for their main power supply. This works just fine because the power supply really doesn't need to be regulated. You could use a regulated linear supply, and it would improve the audio performance somewhat, but it would cost more, be a lot bigger and heavier, and be less efficient. This is because the ways in which you can regulate a linear power supply all involve bigger and more expensive parts, more complicated designs, and more wasted heat. A switch mode power supply (SMPS), like the one we use in the XPA Gen3 amps, is inherently regulated (regulation is part of how they work). So, if you compare the new SMPS to the original linear power supply, the SMPS is somewhat more efficient; more importantly, however, it is also regulated.... and it's STILL more efficient than the unregulated version of the linear power supply it replaces. (If we'd replaced the previous unregulated linear supply with a regulated linear supply, the performance would have improved, but at the cost of more weight, more heat, and, well, more cost. Instead, with the SMPS, we've moved up to a regulated power supply, which improves the audio performance, and also actually improved the efficiency and lowered the cost at the same time.)

The improvements in efficiency due to our Class H topology are also slightly complicated to calculate. At very low power levels, the efficiency of virtually any powerful Class A/B amp is going to be very low. (It's drawing some minimum amount of idle current to keep the circuitry warmed up, and putting out nothing much in return.) At full power, the efficiency of any Class A/B power amp is generally around 70% - and is determined by the relationship between the rail voltage and the maximum output voltage it's being called upon to deliver.

However, as already noted, most amplifiers spend almost all of their time operating somewhere between those two extremes. Because an amplifier with a Class H topology has two different power rails, instead of having a single point in its power curve where it's operating at maximum efficiency, it's got TWO different points where it's operating at or near maximum efficiency. So, with a signal like music, which ends up demanding a wide variety of different power levels, the amp can operate more efficiently more of the time. (If you were to graph the efficiency of an ordinary Class A/B amp, and one with a Class H topology, you would find that  the graph for the Class H amp spends more time in areas of the curve where it's more efficient. The exact difference would, quite literally, depend on the exact song you were playing, how loudly you were playing it, and even on the impedance of your speakers. But, overall, the efficiency is going to be significantly better, which means significantly less waste heat.)

To be honest, I doubt your home theater system accounts for much of your electric bill to begin with, and the difference between Class A/B and Class H is unlikely to make a noticeable difference in it.
(But the amp will run cooler.... and you might actually get to run your air conditioner a little bit less.)

Sept 27, 2017 18:17:20 GMT -5 Gary Cook said:

Sept 17, 2017 2:55:26 GMT -5 zappagoo said:

Thanks! I've heard about the XPR but I don't have a dedicated outlet rated for it. But what a sweet deal!

You realise that's not logical right? With very similar efficiency any power (volts, amps, watts) out of the power point will limit any amplifier to the same watts out (volume). So if, for example, the XPA-2 hits the power input limit and can only reach say 250 watts per channel then the XPR-2 will be limited to pretty much the same, 250 watts. Except the XPR-2 will sound better because firstly they are designed/engineered/spec'd to and secondly because they will be running at a lower wattage output that may well be at a better point in their performance.

In simple terms the power point output limit is the same for any Class AB amplifier plugged into it. If you want more watts out for less power in then you need to look at alternative amplifier designs, the trick is finding out exactly how many watts they output for how many watts input. For sure Class H power supplies (SMPS) as found in Gen 3's are claimed to be more efficient, but how much more? It would be nice if the amplifier manufacturers quoted watts in versus watts out that way we could tell if its a worthwhile efficiency gain. Being sceptical, as I am, since they don't I expect that it's not much.

Another option is to look for a Gen 1 Emotiva amp as they have 32 db gain whereas the later models have 29 db.

Cheers
Gary

[KeithL]

You've got sort of the right idea.......
However, the power supply in the amplifier acts as a reservoir for power.... so the amp never draws power directly from the line.
The ONLY reason we might care about how the waveform on the power line looks is that it might affect the voltage on the power supply rails.
Therefore, yes, if your amp draws enough current at the peaks of the power waveform, it may cause the power line waveform to clip (or usually to sort of soft-clip).
However, the net result of that will be that less peak voltage will be available, so it will cause the power supply rails in the amp to be slightly lower.
The end result of this will be that the maximum output power of the amplifier will be slightly reduced.
This, in turn, will mean that the amp will clip at a slightly lower output power (but the difference in dB will be tiny).
HOWEVER, until the amp does clip, the distortion on the power line waveform will NOT directly cause distortion in the amplifier output.
All the amp cares about is the voltage of its supply rails; it does NOT care about the AC waveform on the power lines that those rails are derived from except as it affects the rails themselves.

To be strictly accurate, you wouldn't want extreme waveforms, like pure square waves, coming in the power line - because the circuitry in the amp isn't designed to accept them.
However, any reasonable amount of distortion on the power line sine wave is NOT going to affect anything except the voltage of the power rails.

And, yes, because our SMPS is regulated, it's much less affected by this sort of thing than the old style linear supplies.
Basically, instead of filling the power supply reservoir from the power line, the SMPS fills an incoming reservoir from it, then fills the main reservoir from that one, through the regulation circuitry.
The regulation circuitry keeps changes in the power line from having a significant effect on the power reservoirs that provides operating power for the amp.

The B&O IcePower modules have both an SMPS and a Class D amplifier on them....

Sept 27, 2017 19:10:02 GMT -5 leonski said:

I don't buy this. As a 20 amp 'rated' amplifier runs on lesser current, it'll 'clip' the power line voltage as you run out of juice. That's Distortion.
The more powerful amp will have higher voltage rails which only charge the caps as they drop below that voltage. At voltage peaks is where it's gonna 'clip.
I suppose at some point recharge rate comes into play, but given the AC frequency, you've only go so many opportunities for the 'recharge'.
The voltage and voltage DROP count.

You're better off with a lesser powered amp at that point.

B&O modules that include an OnBoard PS are rated 'plug to speaker' for efficiency, which is mid-high 80s at full power. Rating an amp for output stage only is disingenious, IMO.

I'm likewise certain that MOST persons will NEVER stress an amp to its limits. HT speakers are fairly sensitive and even if only about 1% efficient, still good at turning electricity into sound. To that end,
you're OK with the high power amp with other gear on a high power circuit. Just don't expect max power from everything simultaniously.

You CAN run your Porsche on Regular Gas and put H-Rated tires on it, but you don't quite have what the designer intended.

[leonski]

One minor skipped point about regulated V unregulated PS? It would seem that 'floating' the rails above the voltage needed provides opportunity for a dynamic power above that of the RMS value. With a highly regulated PS, be it switcher or linear, you can have a situation with nearly zero dynamic power.

And while you will get quite a bit of performance out of an amp running on a 15amp circuit which the 'book' says needs a 20, you're still not getting what you paid for.

I'll drop this issue but remain convinced that in MOST cases, an audio guy would be better served by either skipping the amp requiring a 20 amp service OR installing such a service.

[KeithL]

Errrrr....... that's not really the way it works with "mains powered" equipment.

If you have a "12V wall wart" it may well actually deliver 15V with no load, and 12V at rated load.
However, if that same supply were inside a piece of equipment, it would be referred to as "a 15V power supply that drops to 12V under full load".

In general, when you have an unregulated power supply, running off a transformer, under no load, the capacitors will charge to the peak voltage of the output of the transformer.
This will be 1.4 x the RMS output voltage minus a loss of about 1.4V in the rectifiers - and will be considered to be the rail voltage.
That voltage will then drop - or "sag" - when you load it down.
The amount of noise present on the DC output of the power supply will also increase under heavier loads.
In contrast, a regulated supply will NOT sag when you load it down - at least over a rather wide variation in load - and should have virtually no noise on it at all.

This is a different situation than when you talk about dynamic power.
Dynamic power usually refers to the amount of power an amplifier can deliver for a few seconds compared to what it can deliver long term.
The two are related, and can sort of overlap..... and you could design a "very soft" power supply that floated very high under no load, but still had big capacitors, that might act sort of how you're envisioning it....
However, in most cases, while an unregulated supply may have a tiny bit more dynamic output, the most noticeable difference will be that the regulated supply performs more consistently.....

There are some relatively minor distortions caused by the fact that an unregulated supply shifts its voltage dynamically as the load changes - which does slightly affect the audio circuitry.
The noise present on all unregulated power supplies also affects the audio signal to some degree.
Because the output voltage of a regulated supply doesn't shift under load, and contains virtually no noise, a regulated supply is immune to both of these distortion mechanisms.
(Note that most well-designed amplifier circuits are mostly immune to distortion from these causes - but not 100%.)

In point of fact, the XPA Gen3 will deliver its specified performance when running from a 120 VAC 15 amp outlet.
However, the slight drop in specified performance with all channels driven will be LESS if you run it from a 220V circuit.
It's absolutely not a big deal, and you won't notice it with music, but by the "test set numbers" it is there.

Sept 28, 2017 12:55:31 GMT -5 leonski said:

And while you will get quite a bit of performance out of an amp running on a 15amp circuit which the 'book' says needs a 20, you're still not getting what you paid for.

I'll drop this issue but remain convinced that in MOST cases, an audio guy would be better served by either skipping the amp requiring a 20 amp service OR installing such a service.

[leonski]

Sept 28, 2017 8:47:34 GMT -5 rbk123 said:

Sept 27, 2017 23:12:49 GMT -5 leonski said:

That's true.   Than WHY buy the big power amp which 'theoretically' asks for a 20 amp circuit?

Like Audioh said - because it is the better sounding amp regardless of 15A or 20A circuit. You buy an amp for it's sound, not for it's spec. If a 2W amp sounds better than a 2000W amp, in someone's use case, they go with the one that sounds better. If the 4000W XYZPR sounds better than a 200W Macintosh, you get the 4000W XYZPR even though you don't need the wattage.

Unclipped, I defy anyone to tell the difference driving the normal, run-of-mill HT stuff most persons here have.   'Better' is so subjective and people CAN talk themselves into
nearly anything.    

I doubt also, even with my very low sensitivity panels you'd ever tell the difference except maybe at the very highest levels.   You CAN clip panels.   It's called 'mylar slap'.
Maybe with some speakers of Notoriously Bad load.     Some Thiels or B&Ws might qualify.    

And running the amp on a 15 amp circuit that is spec'd for 20?    Have you read what some people plug into a single outlet or circuit around here?     I can understand completely an apartment dweller not digging into the walls, but a homeowner?    Generally NO reason whatsoever to not have what the amp wants.   

[pknaz]

Emotiva doesn't publish "peak" power output, but for the sake of argument, let's assume that their amps cannot deliver any level of power above published RMS specs.

Let's say you want 20db of headroom for music peaks above your average comfortable listening level. Let's say your average comfortable listening level is 95db. Let's assume your main listening position is 4 meters from the speakers. In a theoretical world, this would be a 12db drop at the main listening position. It's pretty well established that in residential sized spaces, you do _not_ lose the typical -6db per doubling of distance due to room gain. But let's just go with the -12db for argument's sake. This means we need to produce 127db 1 meter from the speakers for our 115db target, which would result in the following power requirements:

• 1 Watt/1 meter: 91db
• 2 Watt/1 meter: 94db
• 4 Watt/1 meter: 97db
• 8 Watt/1 meter: 103db
• 16 Watt/1 meter: 106db
• 32 Watt/1 meter: 109db
• 64 Watt/1 meter: 112db
• 128 Watt/1 meter: 115db
• 256 Watt/1 meter: 118db
• 512 Watt/1 meter: 121db
• 1,028 Watt/1 meter: 124db
• 2,056 Watt/1 meter: 127db

This is completely unsafe for your ears, and you will lose hearing:

For a more real world example
Let's assume a more realistic 5db drop at a 4 meter distance (fudge number) in an average room size with modest absorption (Chairs, couch, carpet, etc.), the THX spec of 85db average and a slightly less efficient speaker of say 89db/w/m and we have a more realistic power requirement to hit our new target of 105db peak at the main listening position (110db at 1 meter from speakers):

• 1 Watt/1 meter: 89db
• 2 Watt/1 meter: 92db
• 4 Watt/1 meter: 95db
• 8 Watt/1 meter: 98db
• 16 Watt/1 meter: 101db
• 32 Watt/1 meter: 104db
• 64 Watt/1 meter: 107db
• 128 Watt/1 meter: 110db

A 15amp circuit breaker will allow 1.5 times the rated current for up to 400 seconds or 2 times the rated current for up to 100 seconds
static.schneider-electric.us/docs/Circuit%20Protection/Molded%20Case%20Circuit%20Breakers/0100-400%20A%20Frame%20FA-LA/FA-FC-FH/0600DB0105.pdf


With this more real world scenario, I can quite happily power my dual XPA-1's, an XPA-7, four SA1000 sub amps, my XMC-1, my 55" Plasma, and a host of other equipment in my room on two 15amp circuits without breaking a sweat.  As you can see, I'm not stressing any of my equipment in the slightest.

[rbk123]

Sept 28, 2017 21:19:18 GMT -5 leonski said:

And running the amp on a 15 amp circuit that is spec'd for 20?    Have you read what some people plug into a single outlet or circuit around here?     I can understand completely an apartment dweller not digging into the walls, but a homeowner?    Generally NO reason whatsoever to not have what the amp wants.   

Yep. And running it on a 15A circuit, it will still sound better because it is a better amp.

[KeithL]

I would suggest that anyone who is really curious consider buying a Watt Wizard or something similar.
It will tell you exactly how much power your system is using (most of the cheap ones won't catch short peaks, but will give you a very accurate average).
You'll probably be surprised at how little power you're using most of the time.

[leonski]

My Kill-A-Watt is indeed one of the 'cheap ones' and not good a quick transients. But for steady state readings? Fine. Maybe 25$ these days, check Amazon Prime.
It has Power Factor so you can see how 'reactive' the load is, and records KWH for as long as it's plugged in.

And for rbk123? You'll NEVER hear the difference between most EMO amps unless stressed or clipped. See pknaz post above for a possible reason it's Nutty to run major power
when you've got near-100db speakers. And the various amps probably differ in the ability to drive 'bad' loads.

In addition to the time / current limits stated by PKNAZ, the Long Term allowed current from a 15amp circuit is -20%. I think this also applies to a 20 amp circuit.
This probably doesn't apply except in the Most Heavily stressed home situations.
Aren't the numbers you quote for a single speaker? Should you ADD 3db for a second speaker? Also, the -6db often quoted is for a doubling of distance. So, 4 meters = 2 doubles or 12db and
a reasonable number (as you note) would be less. I'd personally go with 9db, but that's just me.
I also suspect that FEW actually listen that loud. And those that do, are suffering long-term hearing loss.
Even a 'reasonable' 100db is rated for only 2 hours per day.
This keeps driving the 'required' power to lower and lower levels. Even my Very Low sensitivity panels never tap the amps I'm using.

And from our FWIW department?    Line Source speakers, like my panels, tend NOT to follow the '6db rule' but rather less.     This has the effect of increasing sensitivity at 
normal seating distances, but by some unknown (to me) value.

At the recent Miramar AirShow, I spoke with a hearing technologist. He noted my Fitted Earplugs. He said that the average, very old African Bushman has BETTER hearing than an American 1/2 his age.

www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=standards&p_id=9735

[rbk123]

Sept 29, 2017 12:57:47 GMT -5 leonski said:

And for rbk123? You'll NEVER hear the difference between most EMO amps unless stressed or clipped. See pknaz post above for a possible reason it's Nutty to run major power
when you've got near-100db speakers.

I disagree - you don't need to stress the Emo amps to hear differences, you just need revealing enough speakers. The differences are quite small however.

I'll turn it around on you - there's no way you yourself will be able to hear a difference if that XPR is plugged into a 15A circuit or a 20A circuit. Even at loud levels. See pknaz's post to see what absurd levels that XPR will begin to run out of gas on a 15A circuit.

[leonski]

rbk123,
You might be right about 15 v 20 in many or most cases. But when push comes to shove, you have a hobbled high power amp with insufficient power. period.
I'd either go all the way and drop a 20 amp circuit TO the amp OR buy lesser powered amps for my 90db sensitive speakers.

As for 'revealing' speakers? My Maggies don't qualify? Sure, I've heard some differences. My 'd' amps were long-term not satisfying and my Rotel was out of the system in 3 or 4 months.
But my Parsounds? (2 @ A23) are keepers.

I suspect however, that in a single line, like EMO or Parasound or perhaps Pass or Macintosh, the family similarity when unstressed makes telling the difference as much hearing as guesswork.

[leonski]

Sept 29, 2017 14:50:40 GMT -5 leonski said:

Duplicate post, to be deleted:     

[fattykidd]

...

Attachments:

[Gary Cook]

Sept 29, 2017 2:53:41 GMT -5 pknaz said:

Emotiva doesn't publish "peak" power output, but for the sake of argument, let's assume that their amps cannot deliver any level of power above published RMS specs.

Let's say you want 20db of headroom for music peaks above your average comfortable listening level. Let's say your average comfortable listening level is 95db. Let's assume your main listening position is 4 meters from the speakers. In a theoretical world, this would be a 12db drop at the main listening position. It's pretty well established that in residential sized spaces, you do _not_ lose the typical -6db per doubling of distance due to room gain. But let's just go with the -12db for argument's sake. This means we need to produce 127db 1 meter from the speakers for our 115db target, which would result in the following power requirements:

• 1 Watt/1 meter: 91db
• 2 Watt/1 meter: 94db
• 4 Watt/1 meter: 97db
• 8 Watt/1 meter: 103db
• 16 Watt/1 meter: 106db
• 32 Watt/1 meter: 109db
• 64 Watt/1 meter: 112db
• 128 Watt/1 meter: 115db
• 256 Watt/1 meter: 118db
• 512 Watt/1 meter: 121db
• 1,028 Watt/1 meter: 124db
• 2,056 Watt/1 meter: 127db

This is completely unsafe for your ears, and you will lose hearing:

For a more real world example
Let's assume a more realistic 5db drop at a 4 meter distance (fudge number) in an average room size with modest absorption (Chairs, couch, carpet, etc.), the THX spec of 85db average and a slightly less efficient speaker of say 89db/w/m and we have a more realistic power requirement to hit our new target of 105db peak at the main listening position (110db at 1 meter from speakers):

• 1 Watt/1 meter: 89db
• 2 Watt/1 meter: 92db
• 4 Watt/1 meter: 95db
• 8 Watt/1 meter: 98db
• 16 Watt/1 meter: 101db
• 32 Watt/1 meter: 104db
• 64 Watt/1 meter: 107db
• 128 Watt/1 meter: 110db

A 15amp circuit breaker will allow 1.5 times the rated current for up to 400 seconds or 2 times the rated current for up to 100 seconds
static.schneider-electric.us/docs/Circuit%20Protection/Molded%20Case%20Circuit%20Breakers/0100-400%20A%20Frame%20FA-LA/FA-FC-FH/0600DB0105.pdf


With this more real world scenario, I can quite happily power my dual XPA-1's, an XPA-7, four SA1000 sub amps, my XMC-1, my 55" Plasma, and a host of other equipment in my room on two 15amp circuits without breaking a sweat.  As you can see, I'm not stressing any of my equipment in the slightest.

I would add that stereo means 2 channels/amps/speakers so +3db above what one speaker outputs. I also always run a sub woofer, hence 2.1,  have for decades, with the mains at full range, that's another 3 db below the cross over frequencies. My speakers are not close to the walls and are across the corner but there is still some boundary gain, likely another 3db.   At 30 watts of Class A from the XPA-1L's that's more than enough for 120 db peaks. 

Being in Australia we have 220/240 volts at 10 amps per outlet and 15 amps per circuit, so no issues here.  

Cheers
Gary

[leonski]

Good Approach, Gary. I differ in that I low-cut my mains which 'cleans up' the image eliminates 'muddines' in the lowst octave or so.

[Gary Cook]

Sept 29, 2017 17:46:05 GMT -5 leonski said:

Good Approach, Gary. I differ in that I low-cut my mains which 'cleans up' the image eliminates 'muddines' in the lowst octave or so.

With the XSP-1 I wanted to stay full balanced, discrete, differential from the ERC-3 through to the XPA-1L's and that means full range to the mains. Having played with it for a while it sounds better that way as longs as the sub low pass is around 60 Hz. Above that it's a bit bass dominant and below it leaves a dip. Most importantly it sounds OK to me, which is how I set it up, and as a bonus it's tests OK, which I did some time later just to confirm that I wasn't imagining it. It's pretty linear with a couple of db here or there between 10 and 100 Hz, the room is good, so that helps.

Cheers
Gary

[leonski]

My panels are of course Dipole. They have a nice 'null' off to each side of the panle where front / back waves cancel.
Integrating with a sub is one of those trial and error things.
My first position for the sub resulted in REAL muddy bass, and my den turned into a Helmholtz (one note) vibration chamber.
Mains were running full range, at that time. Experimenting with crossover settings on the sub didn't help.

I went thru an upgrade cycle, not being real happy with my 'd' amp integrated. Since I went with seperates this time around, I really shopped preamps. I chose one with reasonable bass management features and
now cut bass to the mains and while I run the sub as 'full range', it has it's own 24db / octave crossover which I set somewhat below the 12db /octave of the preamp to the mains. Than I relocated the sub to the OTHER
side of the front away from the corner where it had been. Without changing ANY settings on the sub, problem solved.
As an aside, the lowering of the power needed to the mains helped raise the relative power VS the highs. The panel crosses over at 600hz which is a little above the 50:50 power point. I think right now my amps run out of
steam about the same point, depending on what's playing.

Later intent is to go to an active crossover, maybe a MiniDSP of one flavor or another.