CR Treatment and Tuning---The home stretch!!

Also, don't forget that you'll need to make a new back panel to fill in the hole where the amp panel was: that's an integral part of the speaker's acoustics. Use something of similar density and thickness, and replace any insulation that might fall out. - Stuart -

oh bummer....something else to figure out... :roll:

I don't recall off hand, but is that a wood panel, or a metal panel? Aluminium? If aluminium, you can probably get a piece of scrap some place that works in aluminium. By the way, I just looked at the model again, and the hole through the insulation will need to be a little lower than I said, because there a 2x4 on edge right there, supporting the speaker shelf inside the soffit. So make your hole just under the 2x4... There's still plenty of ventilation like that. - Stuart -

Hey, Frank: Not trying to make you nervous, or feel like you are in the spotlight, but the view counter on your thread just clicked over 10,000 views! You seem to be pretty popular... lots of people following what you are doing... :) - Stuart -

That is cool, Although I imagine the total number of people to be lower based on how many times people repetitiously visit the thread. :-P Its fun to know that people are sharing in the experience somehow. Not too many people wanna help bake the bread round here.... :shot: Got the final speaker shelves cut out and fit into place. I still need to figure out how I'm going to physically locate the holes for the turn buckles. I don't have any trusted surfaces for reference in the soffits. I'll figure something out. :jammin:

Hi Stuart, I just noticed that the vent cutouts have different sizes getting smaller from bottom to top. Is this on purpose. Why would the cutouts need to get smaller from bottom to top? Thanks

They shouldn't. I probably forgot to update something. The ones in the shelf under the speaker and the top of the soffit enclosure should be the same size as each other, and the ones in the top and bottom panels of the enclosure box should also be the same size as each other. Yes, there is a difference in size between the enclosure box slots and the soffit panel slots: the soffit panel slots are larger, since they carry all of the cooling air, but the slots in the top and bottom panels of he enclosure box are a bit smaller, since they only carry the cooling air that flows up directly past the rear panel of the speaker. But that's not the only path that the air can take: it can also flow up around the sides and front of the enclosure box, as well as through the holes in the rear panel of the enclosure box: hence, the soffit panels have larger slots than the enclosure box. But I'll check the sizes again tomorrow, and send you an updated morel if necessary. I might have missed something. It's not critical, though, as there's plenty of space for airflow: I oversized it relative to what is really needed, to make sure that there's more than enough flow, and in any case you won't have the amps on the back of your speakers, so there's actually less heat to deal with than I planned for originally. - Stuart -

Thanks. Just wanted to make sure there is no tuning of any kind involved with the structure. No need for you to be too bothered. I can interpolate what I got. I'll just go 3" width top and bottom shelf. Just let me know what you want on the enclosures. Could I just cut bigger holes top and bottom and skip doing cutouts on the backs?

Could I just cut bigger holes top and bottom and skip doing cutouts on the backs?

I would prefer to keep it it pretty much as is. Making bigger slots in the top and bottom might weaken them too much, and there's quite a bit of stress on the top panel from the mounting system-that-shall-not-be-named! :) I want it to stay square, plumb and rigid with all the tension on there, without bowing or twisting. Also, the cutouts in the back panel serve an acoustic purpose too: I don't want resonances going on inside the enclosure box, and those help to reduce the possibility of that. The size and location of those cutouts is not too critical, so you don't need to cut them with high precision, but I'd still like to keep them there, more or less like they are. In the original design, before you decided to remove the amps, they also had an additional purpose: cable access. You would have run your power and signal cables through those cutouts, and you also would have used them to get at the controls on the rear panel, without needing to remove the speaker from the enclosure. Those two are moot now, as you won't have the amps in there, some from that point of view you don't need them, but from the other points of view, I'd leave them in pace, roughly how they are. - Stuart -

Sounds good....

looking at my numbers. I don't currently have enough homasote to do hangars both top and bottom. Can I use something else on the bottom instead? I have enough to do the top hangars which is all I need for the moment.

looking at my numbers. I don't currently have enough homasote to do hangars both top and bottom. Can I use something else on the bottom instead? I have enough to do the top hangars which is all I need for the moment.

Both are important! If you only have enough for one set, and really can't afford more right now, then do hangers at the bottom, and we can partially fill the top section with insulation, but you have to do it carefully, so as to not block the air flow, yet still keep it thick enough to go down low in the spectrum. Or are you speaking in a temporary sense? Meaning that you can buy some more homasote soon, then do the other hangers? - Stuart -

I can order snother sheet of homasote. I already cut the top hangars with what i had left. I was hoping i could do the bottom with plywood scraps but it sounds like thats a "no".

I was hoping i could do the bottom with plywood scraps but it sounds like thats a "no".

:thu: Correct. Unfortunately. Plywood is way to dense and rigid, compared to Homasote. Plywood is around twice as dense, and more rigid. We could substitute the insulation, if we really had to, but not the core. - Stuart -

Ok, so I ordered another piece of homasote to cover the rest. Now I am too short on 703 1" , but not by a lot. Hoping I can just do some rockwool pulled apart to thickness on a small hangar per side. I have enough 703 for the rest. Hate to have to drive 1 1/2 hours each way to get a 2x4 sheet...

Hoping I can just do some rockwool pulled apart to thickness on a small hangar per side.

:thu: Yeah, that's fine. - Stuart -

Hi Stuart, Running out of stuff to do here. Thanks. 8)

That's good news! Please e-mail me pics of where you are, and I'll give you some more stuff to keep you busy! Playing with Sorbothane is fun! (not so much...) - Stuart -

Finishing the hangars and some insulation. I'll post pics in a couple of hours.

Actually, was there any reason for me to wait on cutting up the box pieces? I was holding off thinking you needed to check things on your end. It won't take long to fabricate those because its all done on the table saw. I can whip those up by the end of today.

Let me just double-check the dimensions of the enclosure boxes, and I'll get back to you. To do that, please confirm what type and thickness Sorbothane sheets you already have, to see where I can fit those in, and if you'll need to order other stuff. Don't forget that you got that stuff for the other speakers (before switching to the Trios) and original soffit design, so it might not be applicable here. I can probably still use it under the boxes, but perhaps not inside them. I'm sure you get what I mean, without going into details that would reveal too much ... :) - Stuart -

I a (12" x 12") 1" thick duro 50 sheet of Sorbothane.

Cool! We can use that. - Stuart -

Awesome! Those sheets cost about 200 bucks a piece...