7.1.4 basement HT build

Posted by: bman84

7.1.4 basement HT build - 09/29/18 02:09 PM

Pulling the trigger on a new 7.1.4 HT setup for my basement in the next few days. Room dimensions are about 23' long, 13' wide, with 7.5' ceilings. My wife doesn't like to see speakers, so i'll be going in-wall as much as possible. Any issues with these selections?

  • Fronts: M5HP In-wall
  • Center: VP180 (Standard)
  • Sub: EP500
  • Surrounds: M3 In-Wall
  • Overhead: M3 In-ceiling
  • Receiver: AVR-X4400H (powering surrounds/ceiling)
  • Amp: ADA1000 3-channel (powering L/C/R)
  • TV: Vizio P-series Quantum 65" (if they ever show up in Canada)


Posted by: Mojo

Re: 7.1.4 basement HT build - 09/29/18 02:22 PM

You don't need the 180. You won't miss anything with the 160v4. You can also get that in an in-wall.

As for your in-wall constraint, poor you!
Posted by: bman84

Re: 7.1.4 basement HT build - 09/29/18 02:36 PM

Originally Posted By Mojo
You don't need the 180. You won't miss anything with the 160v4. You can also get that in an in-wall.

As for your in-wall constraint, poor you!


Thanks. 180 is shorter, which allows it to fit better below my tv. I've only got about 60" of vertical to work with to fit the tv stand, center channel, and tv.

Is the 180 a bad match for the rest of the setup?
Posted by: Mojo

Re: 7.1.4 basement HT build - 09/29/18 02:57 PM

I see. No, sonically it's a great match.
Posted by: bman84

Re: 7.1.4 basement HT build - 09/29/18 03:15 PM

Originally Posted By Mojo
I see. No, sonically it's a great match.


Awesome. As an added bonus, the 180 is 4-ohm as well. I'm assuming there's no issue for a single amp to drive 8-ohm loads on 2 channels, and a 4-ohm load on a third channel?

On the numbers side, it's only $72 more for me to get the 180 over the 160 (180 happens to push me into the next loyalty discount tier).
Posted by: Mojo

Re: 7.1.4 basement HT build - 09/29/18 04:05 PM

There's certainly no issue with the ADA amps to drive differing impedances for any Axiom speakers.
Posted by: nickbuol

Re: 7.1.4 basement HT build - 09/29/18 04:05 PM

Nice. You may have some issues with in-ceiling overheads for such a low ceiling. My ceiling is about 7ft 9in, and it was tricky getting Atmos dialed in. I have a "soundproofed" room, so I wanted as few of holes in my double drywall with GreenGlue ceiling, and that was suspended on a whisper clip & hat channel isolation system that made it nearly impossible to find the right locations without hitting a joist or hat channel to put a speaker up into the ceiling.

So I had to go with non-in-ceiling speakers. I went with on-wall M3s that the fronts were mounted using Axiom Full Metal Brackets so that I could angle them toward the listening area due to the low ceiling. The rear overheads (also on-wall M3s) were mounted on just a basic wood block that was cut to give them an angle towards the listening area more as well.

That was all in the plan, but I spent weeks tinkering before I decided to relocate them completely and start over. That is a big challenge with in-ceiling speakers unless you are good with drywall repair.

So your speaker choices are nice, but your room may be your arch enemy for the overhead speaker placement.

The good thing is that the in-ceiling M3s have an aimable tweeter which helps with better alignment for low ceiling Atmos, but still not a great situation.

Outside of the low ceiling problem, your room size is nice. In fact all of your dimensions are close to mine. Mine is 14 feet wide x 24 feet long x 7.75 tall.
Posted by: bman84

Re: 7.1.4 basement HT build - 09/29/18 04:15 PM

Originally Posted By nickbuol
Nice. You may have some issues with in-ceiling overheads for such a low ceiling. My ceiling is about 7ft 9in, and it was tricky getting Atmos dialed in. I have a "soundproofed" room, so I wanted as few of holes in my double drywall with GreenGlue ceiling, and that was suspended on a whisper clip & hat channel isolation system that made it nearly impossible to find the right locations without hitting a joist or hat channel to put a speaker up into the ceiling.

So I had to go with non-in-ceiling speakers. I went with on-wall M3s that the fronts were mounted using Axiom Full Metal Brackets so that I could angle them toward the listening area due to the low ceiling. The rear overheads (also on-wall M3s) were mounted on just a basic wood block that was cut to give them an angle towards the listening area more as well.

That was all in the plan, but I spent weeks tinkering before I decided to relocate them completely and start over. That is a big challenge with in-ceiling speakers unless you are good with drywall repair.

So your speaker choices are nice, but your room may be your arch enemy for the overhead speaker placement.

The good thing is that the in-ceiling M3s have an aimable tweeter which helps with better alignment for low ceiling Atmos, but still not a great situation.

Outside of the low ceiling problem, your room size is nice. In fact all of your dimensions are close to mine. Mine is 14 feet wide x 24 feet long x 7.75 tall.


Great info, thanks! I'm starting out with an unfinished space, so I'm hoping to be able to scope it all out beforehand. My ceiling joists run the width of the space, which helps.
Posted by: bman84

Re: 7.1.4 basement HT build - 09/30/18 10:59 AM

Originally Posted By Mojo
You don't need the 180. You won't miss anything with the 160v4. You can also get that in an in-wall.

As for your in-wall constraint, poor you!


Thoughts on the VP160 mini? If I go with the VP160 instead of VP180, I'd likely have to put it below the tv in media cabinet. Fitting the full-width VP160 would be a struggle in there.

While the VP180 would be cool, but it's such a beast that my wife would likely freak. I also prefer the idea of the more central, tightly focused output from the VP160.

With the VP160 mini, it would cost a whopping $77 to upgrade to the 6.5" High Powered woofers (a match to the woofers in the M5HP in-walls that I'm using on the left and right).
Posted by: Mojo

Re: 7.1.4 basement HT build - 09/30/18 11:31 AM

Sorry but I have no experience with the mini and can't even hazard an educated guess. It's design is acoustic suspension so I'd be concerned it sounds congested. But you know what? If you think it sucks, there's always the other options.

Too bad you can't find a way to make an M5 work as a centre.
Posted by: bman84

Re: 7.1.4 basement HT build - 09/30/18 11:36 AM

Acoustic suspension = sealed? I believe all of the in-walls are the same.
Posted by: Mojo

Re: 7.1.4 basement HT build - 09/30/18 11:41 AM

Yes but I have never heard or read a complaint about in-walls sounding "nasal" or "boxy". Unfortunately my VP150v2, which is also sealed, did sound nasal so that's why I'm hesitant about the mini-160. If it was me and I was faced with your problem, I'd go ahead with the mini because I'd know if I thought it was bad, Axiom would make it right by allowing me to go with another option. It is a pain to have to go through that though.
Posted by: bman84

Re: 7.1.4 basement HT build - 09/30/18 11:48 AM

Ah gotcha. Maybe I just go with the full 160 and find a way to make it work. Could always build a custom media cabinet or something.
Posted by: Mojo

Re: 7.1.4 basement HT build - 09/30/18 11:50 AM

Maybe consider making a single M5HP work instead of a 160.
Posted by: bman84

Re: 7.1.4 basement HT build - 09/30/18 12:16 PM

Good call! Has anyone done that before? M5HP bookshelf dimensions are definitely easier to work with. I wouldn't be losing too much sound vs a full blown 160?
Posted by: bridgman

Re: 7.1.4 basement HT build - 09/30/18 12:28 PM

The problem is that AFAIK you would really want the M5HP to be vertical rather than horizontal.
Posted by: Mojo

Re: 7.1.4 basement HT build - 09/30/18 12:40 PM

John is right because the tweeter has wide horizontal dispersion but relatively narrow vertical dispersion. I was thinking of mounting it vertically but I should have said so because not everyone is aware of how these things work.

As for how much you'd lose, I can't say because I haven't tried but I will over the next month or so since M5HPs are coming my way. smile My vote would be on not losing anything in your use case because you won't be pumping 400W into it.
Posted by: bman84

Re: 7.1.4 basement HT build - 09/30/18 12:54 PM

Ah, was not aware of the dispersion factor, thanks. Couldn't I just rotate the tweeter 90 degrees? Or even ask Axiom to do that when building the speaker?
Posted by: Mojo

Re: 7.1.4 basement HT build - 09/30/18 01:09 PM

No, it doesn't work that way. The drivers all work in unison with the cabinet and the cross-over as a system. You can't just rotate a tweeter and expect goodness. There is a whole Family of Curves, likely thousands for the M5HP, that had to be analyzed and optimized to make it sound like the (apparently) holy thing it is. So if they rotate the tweeter, it's a whole new product and engineering effort to boot! You're not just buying speakers here you know. You're buying a whole lotta science and blood and sweat and tears these folks have gone through to engineer these boxes.
Posted by: nickbuol

Re: 7.1.4 basement HT build - 09/30/18 01:26 PM

Rotating the tweeter won't do anything as the tweeters are omnidirectionl (sending sound in all directions).

Picture a "barrier" between each tweeter and woofer. If you put a speaker like the M5 on its side, those barriers will prevent the sound from going full left to right in your room as the tweeter will be "blocked" by sound energy coming from the 5.25" woofer, and the 5.25" woofer is somewhat "trapped" between the tweeter (yes, it would overpower the tweeter, which is another problem) and the 6.5" woofer. Now the 6.5" woofer is like the tweeter. One side completely open and free, and the other side boxed in by the 5.25". Again, these are all left-to-right limitations when the speaker is on its side.

Put that same M5 in a normal vertical position and those "barriers" are no longer left to right stopping the listeners across the room from hearing the same quality speaker, but now they are top to bottom, and no limits left to right. That means that in theory, a person sitting to the left or right (within reason) of the middle listening seat will hear the same about of tweeter, the same amount of 5.25" and the same amount of 6.5" as everyone else. The sound is free to go left and right without (as much) cancellation as if done on its side.

There are ways to combat this like done in the VP180, but there are a number of people that say that it is best to put the tweeter above (or below I suppose) the woofers in a center channel, just like any bookshelf or tower speaker has them. That is why the VP160 has the tweeter above the woofers in its configuration.
Posted by: Mojo

Re: 7.1.4 basement HT build - 09/30/18 02:01 PM

Yup. What Nick said.
Posted by: bman84

Re: 7.1.4 basement HT build - 09/30/18 02:05 PM

Great explanations, thanks guys! Not sure how I can pull off an M5HP for center, given the height. It would have to sit basically at floor level, which would probably hurt the sound.

I think i'm leaning towards the VP160 (non-mini) for center duty. Is it worth it to spend the extra $168 to add HP drivers? I'll be using an ADA1000 to drive L/C/R.
Posted by: Mojo

Re: 7.1.4 basement HT build - 09/30/18 02:42 PM

I have not noticed any issues running my standard 160 and I have it crossed at 40Hz. I think you'd blow your ear drums out and melt your eyeballs with sound pressure long before the standard 160 gave out. I have an ADA-1000-3 coming as well as the M5s. And QS10s. Good call on the 160 BTW. It's an amazing centre channel.
Posted by: bman84

Re: 7.1.4 basement HT build - 09/30/18 03:03 PM

Originally Posted By Mojo
I have not noticed any issues running my standard 160 and I have it crossed at 40Hz. I think you'd blow your ear drums out and melt your eyeballs with sound pressure long before the standard 160 gave out. I have an ADA-1000-3 coming as well as the M5s. And QS10s. Good call on the 160 BTW. It's an amazing centre channel.


Nice. What's powering your 160 currently?
Posted by: Mojo

Re: 7.1.4 basement HT build - 09/30/18 03:55 PM

My Onk TX-NR818. Now some who read this may think "Well, that's just an integrated receiver. If you had a real amp you'd tax your 160." I don't think so though. I sit 14' away from my 160 so at 1 Watt in, I am getting 80dB of SPL out. 80dB for me is loud. But let's say I'm feeling particularly feisty because I've had a sarsaparilla so I crank it to an average of 4W. Now I'm getting blasted by 86dB. That for me is a very uncomfortable nominal level. Even so, at 4W, I have another 15dB of headroom for music "transients" before my Onk reaches 64W. At 64W, the regular 160 doesn't even break a sweat because it's rated 250W continuous and 1000W dynamic.

You can see therefore how ridiculously loud one would have to be playing before the regular 160 is taxed or conversely how far away they'd have to be sitting from it. Then of course there's the question of how much better is the HP version which none of us know.
Posted by: bman84

Re: 7.1.4 basement HT build - 09/30/18 04:05 PM

Wow! Sounds like an ADA1000 should be more than enough to really crank it, and anything more is just for bragging rights.
Posted by: Mojo

Re: 7.1.4 basement HT build - 09/30/18 04:09 PM

Exactly!
Posted by: bman84

Re: 7.1.4 basement HT build - 10/01/18 03:59 PM

Originally Posted By Mojo
My Onk TX-NR818. Now some who read this may think "Well, that's just an integrated receiver. If you had a real amp you'd tax your 160." I don't think so though. I sit 14' away from my 160 so at 1 Watt in, I am getting 80dB of SPL out. 80dB for me is loud. But let's say I'm feeling particularly feisty because I've had a sarsaparilla so I crank it to an average of 4W. Now I'm getting blasted by 86dB. That for me is a very uncomfortable nominal level. Even so, at 4W, I have another 15dB of headroom for music "transients" before my Onk reaches 64W. At 64W, the regular 160 doesn't even break a sweat because it's rated 250W continuous and 1000W dynamic.

You can see therefore how ridiculously loud one would have to be playing before the regular 160 is taxed or conversely how far away they'd have to be sitting from it. Then of course there's the question of how much better is the HP version which none of us know.


Talked to Debbie at Axiom earlier today and she told me the same thing, more or less. No need to go HP on the 160, especially with a sub in the room.
Posted by: Mojo

Re: 7.1.4 basement HT build - 10/01/18 07:32 PM

That's right, bman84. Physics in the eastern part of Canada are the same as in the west. smile