New Build CJD (Chris) MTM RS150

[mabrandt]

I'm going to repeat this advice. I think you should post at the PE forum asking to get together with someone in your area for a listen. There are lots of guys within an hour drive of you that can probably help.

Thanks, maybe I will. I have been neglecting some things around the house and need to get caught up. After that I'll see what's up. This started out as a project to fit the space, but now that I have her used to another space, I can make this center pretty much any size. I need to look thru the various plans and see what I can reuse. Your center is a pretty good candidate, I can reuse 2 of the three drivers and use the other driver for the mains if I ever get to them. There was anther center design also that used these drivers. I need to compare the crossover stuff. I imagine they are pretty close in sound.

Thanks.

[mabrandt]

Hi Folks. You guys are probably sick of me by now, but sorry, I just got frustrated last week. I did some research and looked at some other designs, but I keep coming back to these as they fit my needs. The other stuff is either too big (if I had a dedicated room great) or expensive at this time. So I want to go back to this one. I reinstalled the no bsc crossover and it sounds good. Much better than my old center. The more I listen to it, the btter it sounds. I even got it to sound good with audyssey turned on. It actually sounds better there than it does with it off. Audyssey still wants to cross these at 150hz and it doesn't soiund as good there than if I manually cross it at 80Hz. Not a problem, but what am I missing by crossing them at 80 and audyssey is doing no corrections between 80 and 150. Today I got out my old radio shack spl meter and measured tones. i measure at 80 and say I have that at a reference of 0. I lose 3db between 90 and 100. I always have. It's the room. I remember that when EQ'ing my sub a few years ago. All the speakers have a null there. at 100 I am back to 0. At 110 I go up 6db. So I am at +6 until I get to 130 where it drops to -5. That is an 11db difference. at 140 I drop another 4db. It starts to come back at 150 and at 160 I am again at the same level as 80Hz. I ran the tones on my old speakers and the room stuff stays the same, the hole between 130 and 150 is not on the others. I assume that is what Audyssey is seeing and why it wants it at 150.

So I am asking you gurus is there anything I can do to correct this? Can you tell me what might be causing this?

Thanks much.

Mark

[cjd]

Is there an 8 foot dimension multiple times in your room? I think that's what you hit around 140Hz...

[---k---]

Is there an 8 foot dimension multiple times in your room? I think that's what you hit around 140Hz...

Floor to ceiling.

[mabrandt]

No, Nine foot ceilings and the room is about 15X18. Keep in mind, the other speakers don't do this.

Mark

[mabrandt]

This weekend I'm going to put together a ported version of this to compare. I wanted to see how it sounds before doing the mains. I have a question on the port. Plans call for a 3/4 roundoff on the port exit. I do not have a router bit this big and cannot get one that size unless I buy a new bigger router. Was wondering if I can use a 1/2" roundoff? The other question is the port length. Is it measured from the outside of the cabinet or the inside?

Thanks.

Mark