Axiom Home Page Forums General Discussion The Water Cooler Ranked: Factors that matter in sound reproduction

Out of curiosity I double checked my L/R speaker placements and decided to try to get as close to 3:5 ratio as I could. This involved sliding the front speakers back about 3” from where they were sitting. Wow. The imaging and soundstage really opened up and the towers virtually disappeared. Even my six year old said “daddy that sounds better.” Currently my MLP is at 16’ 4” in a toon that is 20’ wide. I have the towers 4’ from the side walls and 29” from the rear wall to the front tweeter. Which leaves about 12” of space from the back tweeter to the wall.

IHambrabi, in a rectangular room modes are predictable, measurable and defeatable. But to beat the modes you must have at least 2 opposing subwoofers. Ideally 4. If you dont have that option (few do!) , placing the listener at a behaved area outside of a peak or null is a must.

Floyd’s point in the powerpoint is multiple subwoofers and where -not modes dont exist or exhibit behaviour in rooms. He is saying a “golden ratio” room size (1:1.6:2.6) or similar is not a must for reproduction.

A perfect speaker, without regard for the other items first, in my opinion, guarantees nothing. Wasnt this the case for people who bought based on Olive score?

I watch all of Andrews videos too. Great fundamental stuff.

I've read two differing opinions with a single subwoofer. Some say to place it in a corner and others say not to.

I think it depends on how what you're looking for in a sub. If it's a flat response ... probably best to stay out of the corners. If you want more boom (for movies or like the boom for your music) putting it in the corner maybe the way to go ... just MO

I've broken every rule in the book except the MLP isosceles. That includes placing my 800v4 at almost the mid-point of the wall behind my MLP. It is absolutely awesome!

I've tried many other locations and surprisingly it sounds very, very good at all of them. Some locations though excite my gas fireplace's fundamental resonant frequency more than others.

I haven't been able to shift my sub around much yet. We haven't finished the wiring across a few walls so I have limited outlets to plug the sub up to. We've been working on the conduit throughout the basement to allow new wires or to replace wires to all speaker locations and also up to the projector location.

My understanding is that oposing subs centered on the wall is one of the better arrangements. I think you once said that you had two 500s up front a the 800 centered in the back which sounds like a great arrangement to me intuitively …

Mojo, now whenever you post something like “excite my gas fireplace …resonant freq” I find I always have more then one interpretation pop into my head … not a pleasant picture …

If you measure the phase response of a speaker or subwoofer you will find placing them away from room boundries leaves the signal intact. Phase plots cycle correctly. Pushing them into corners or against boundaries has the effect of removing phase coherence. Phase plots have incomplete cycles and polarity jumps all over.

Ie. The input signal cannot match the output, and the output cannot be made to match other channels easily at the crossover frequency. The result? High output with low choerence and random cancellation. Not to mention exciting all room modes.

“Boomy” and “slow” bass.

I have an install coming up with a recessed EP500. I will measure it to see what a baffle mount does.

Would it affect anything to set it in a horizontal position? I can’t leave it in its current position bc it’ll interfere with the screen. Thought about getting some fat dots and setting it on its side.

That’s what I’m planning, sub horizontal under the screen. It must be somewhat ok, since Axiom gives you that option, but I always wondered if there was any negative effects (moving driver closer to the floor). I’ve tried it in this position and it sounded fine.

My next step in sub-room integration is to learn more about how Trever is doing it. Best I’ve done is set my 4 sub levels to match the main speakers. I need to learn more about phase, measurements and how they relate to practical adjustments … I.e. just get more applied experience … theory only goes so far.