Square Room with Electrostatics

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ttocs

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The 5&7XW's can't compete with the Statement 40XW. And while the Statement is excellent, it's just not quite able to compete with the 13A for music.

If you want to use that game room with the sloped ceiling, it's much better to use it reversed from what you stated. You want the ceiling to be like an auditorium, with the low point being behind the speakers and the high point being behind you. Otherwise, the bass gets trapped. My room has a cathedral ceiling and the slope starts at 8 feet at the front wall and goes up from there over the seating.

You might want to experiment a little. Take a subwoofer, chair, computer, processor or audio interface, and a microphone, and run REW to find out how the room/subwoofer measures. You can put the sub on the chair, get REW's RTA and Generator running pink noise, then hold the mic in various spots in the room to see in real time how the frequency response looks. It helps to have a second person refresh the RTA response curve when the mic is moved to a new position. The resulting curve can be saved in the current project so you can compare each mic position later. Also, you don't want to run the pink noise continuously for many minutes at a time, the sub's speaker coil can get overworked. So use a low volume and just for a minute or so, then give the sub a rest.

You can do the same in the game room.
 
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Thank you @JonFo for the link to your cube setup, it definitely makes me more comfortable with putting resources into this room. For practical reasons and WAF, the square room is really the only place to put the 13A's, so we are moving forward with the combined movie/music room. I've made changes to the build based on the feedback.

7.2.4 (will bump up to 7.4.4 if needed after listening to two subs with room treatments)
Center: ESL C34A
L/R: ESL 13A
Side and Back Surrounds: 35XTi's
Atmos: MC6-HT
Subs: BF 210 x2 or x4
Receiver: Denon AVR X8500HA , X6700H, or X3800H
External Amps: Emotiva XPA HC-1 Power Amplifier (based on a glowing review from @ttocs, definitely getting 2 for the 13A's, but considering a third for the C34A)

The impedance for the 13A's clearly goes below 4 Ohms, but the specs for the C34A show 6 Ohms Compatible with 4, 6, or 8 Ohm rated amplifiers.
1. Do you think adding the Emotiva XPA HC-1 for the C34A would make much of a difference?
2. If yes, would it be beneficial to upgrade to the AVR X8500HA to accommodate a mono amp for the center channel?

a. The 8500HA has the ability to selectively turn off amplifiers for specific channels.

b. The 6700H only has the option to disconnect the internal amps for the L/R speakers. I understand you can still hook up external amps for any channel on the 6700H, but I don't know if that results in a lower-quality signal.

c. The 3800H doesn't have any flexibility in this regard, has less power but allows up to 4 independent subs. The independent subs might be more important than the potential concerns listed above. @JonFo you said "they even allow one to selectively shut off unused internal amps." However, I think you mean if you just use this as a pre-amp for all channels. From the Denon website Q&A:
With the AVR-X3800H, selecting the pre-amp channels simply involves connecting your power amplifier to the desired pre-outs on the rear panel of the AVR. It is possible to disengage the power amplifier section completely (only worth doing if you have an external power amplifier feed for each channel you plan to use), but the only way to disengage individual channels is to not complete the circuit at the speaker terminals of the AVR-X3800H with speaker wire.

Aside from those concerns, am I making a mistake by using the internal amp instead of a separate amp for all 11 channels?

If it sounds like I am doing research on a topic I know nothing about, it's because that is true.
 
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msimanyi

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First, I'm not the guy who you *really* want answering. We have some truly amazing contributors here who understand complex HT systems and, in particular, best practices for excellent subwoofer integration, and I'm certainly not one of 'em.

That disclaimer aside, I don't think I would want to try to control four subs with any AVR unless it has Dirac Live Bass Control or whatever Trinnov or StormAudio use for multi-subwoofer room correction. I'd rather - and I do - use an external DSP box by MiniDSP and run all my subs through that interface. I use REW and Multi-Sub Optimizer to dial in my subwoofers through the MiniDSP, then I run the room correction on my processor, which sees all the subs as a single sub. I also use a high-level connection to the two front subwoofers so they're in play when I'm listening to two-channel music. (I use separate speaker cables to run from my speakers to the sub-woofers' high-level inputs, but I could also run those wires straight from the amps to the subwoofers. Those cables would have to be a lot longer for the latter though...)

I know that doesn't answer any of your primary questions, but since you're discussing multiple subs in that Oct 20 post, I thought I'd comment about it.

I will offer you my purely WAG comment about the amps though: I would use an external amp for the center channel if you're using separate amps for the main speakers. It doesn't necessarily need to be the same amp as the L/R amps, but there's a bit of flexibility down the road if you do it that way. If one of the L or R amps fails, you can use the center amp as a "backup" for two channel listening while the failed amp is repaired.

And on this question: "I understand you can still hook up external amps for any channel on the 6700H, but I don't know if that results in a lower-quality signal." I'm a bit confused by that. I'm not familiar with the 6700H nor the 8500HA, but assuming they both can put out a low-level signal to an external amp, I would always personally go with external amps for the primary L/C/R speakers. They will *likely* sound better, assuming you're using quality amps. They may also help the lifespan of your AVR/Processor by pulling that heat source out of the component.

Hopefully something in all that above is useful to you. Hopefully one of our talented experts chimes in to give you the answers you really want.
 

JonFo

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1. Do you think adding the Emotiva XPA HC-1 for the C34A would make much of a difference?
2. If yes, would it be beneficial to upgrade to the AVR X8500HA to accommodate a mono amp for the center channel?

a. The 8500HA has the ability to selectively turn off amplifiers for specific channels.

b. The 6700H only has the option to disconnect the internal amps for the L/R speakers. I understand you can still hook up external amps for any channel on the 6700H, but I don't know if that results in a lower-quality signal.

c. The 3800H doesn't have any flexibility in this regard, has less power but allows up to 4 independent subs. The independent subs might be more important than the potential concerns listed above. @JonFo you said "they even allow one to selectively shut off unused internal amps." However, I think you mean if you just use this as a pre-amp for all channels. From the Denon website Q&A:
With the AVR-X3800H, selecting the pre-amp channels simply involves connecting your power amplifier to the desired pre-outs on the rear panel of the AVR. It is possible to disengage the power amplifier section completely (only worth doing if you have an external power amplifier feed for each channel you plan to use), but the only way to disengage individual channels is to not complete the circuit at the speaker terminals of the AVR-X3800H with speaker wire.
Sorry for the delay; busy couple of weeks here.

1. I would definitely use an external amp for the C34

2. Not really, all models have pre-amp outs for all channels.
Since I'm going to recommend the X3800, I don't have an opinion on the other models.

Using external amps usually results in better quality results. Whether the internal receiver amp is on or off should not make a difference, other than heat.

The newer Denons have an auto-sensing circuit in the amps that only powers up the channel if there are speaker wires connected to it. As not everyone has as many speakers as these modern beasts have amps, why generate heat with amps that are not connected to anything?

The X3800 can disable amps per channel (called Pre-Out only) in the UI, as I was reading the AVSForum thread on them this morning.

While the MiniDSP route is a common one for managing multiple subs, and there is a ton of great info out there on their use. It does get technical and involves system integration tasks that have usability impacts. And I say this as a guy with multiple active external crossovers in his system.

The big attraction on the 3800 is the four independent sub outputs and the (future) option to use DIRAC (or the Audyssey variant whenever it's announced) advanced multi-sub integration.

And since we're talking about subs & room correction, I think you will want to skip running ARC on the subs independently and rely on the receiver's Room correction. But maybe others with the BF models can chime in here.
 
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