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

Hi Frank, It looks like you have a great plan for your studio! It looks amazing so far :) Please keep us posted on the results.

Will do...That what this whole thread is about. :thu:

Stadank0 wrote:

Will do...That what this whole thread is about. :thu:

You can actually ignore SarahK, Frank: She's either a troll or a spammer. Not sure which, yet. I'm waiting for her to make her move, then decide what to do about it. But she sure as eggs doesn't act like a normal forum member! And she refuses to follow the rules... However, I do have to echo her sentiment! I'm dying to see how the soffits are working out! :) :thu: - Stuart -

man you are on top of that stuff! Good on ya! :lol: Whenever I read your posts, I see you chasing down those bad guys. Almost seems like a passion for ya. Alright, so I'm filling in the correction angle gap on the left side at the moment. To all of those out there wondering what I'm talking about, I majorly racked the top plates of the framing when I was wrestling with the floor plates back in the way. I didn't catch my mistake until it was too late to correct. I'm correcting the plumb of the left soffit now. Fortunately the issue was isolated to that left corner. The left slider wall is slightly out of plumb too, but it shouldn't affect the listening position I hope.

The left slider wall is slightly out of plumb too,

Not a problem. No issues there.

Whenever I read your posts, I see you chasing down those bad guys. Almost seems like a passion for ya.

You bet! I hate spammers, and scammers, and trolls. They are not an acceptable use of oxygen and sunlight, in my opinion... :) But they never last too long here. By the way, the soffit fix is looking pretty good! :thu: Nice job. - Stuart -

Hi Stuart, I've got the modified framing done. The question is, do I do the Enclosure boxes next? It would be easier for testing to have the side panel completely out of the way. I'm doing the top shelf right now since its not in the way. Will have that finished by the end of the day. Maybe the bottom too.

Cool! Frank's back! :yahoo: Yes, let's leave off the side panels until as far as possible down the line, to simplify the speaker mounting / adjusting. So next up: Enclosure boxes! The tolerances on those are quite tight, so work carefully! Double-check that the size I used for the speaker in the SketchUp model really does match the exact size of your actual speakers. It should, since I took those from the speaker manual, but let's make 100% certain BEFORE we start! Don't want surprises down the line. I also need you to weigh each speaker all by itself, just to be certain that it matches the weight listed in the manuals. Usually it does, but on occasions I have seen a few pounds difference: I suppose because they changed something in the manufacturing process, then never updated the manual to match... - Stuart -

Also, I'm removing the amps, so there's that....

Yup. That will knock off a pound or two! So weigh them after you get the amps off, and the new back panels in place. I'm excited to see the build moving again! :thu: - Stuart -

Frank! We were feeling lonely without your regular progress posts! What are you planning on doing with your amp modules regarding mounting? Greg

Thanks all. I'm definitely back and will be for the rest of this build. To answer your question Greg, I gotta think about that. Probably the best thing will be to mount them in boxes with plenty of slack for maximum placement options. I'm gonna want them to get plenty of ventilation....Not sure where to put them yet. Tomorrow will be the speaker shelves and then starting the enclosure fabrication! I'll get you those speaker weights tomorrow as well Stuart. :thu:

Not sure if you remember, Frank, but when I sent the dimensions for the soffits, there were a couple of images about the amps. Here's some close-ups, without the dimensions: Either way will work, and there's plenty of air space around them, if you set them back a bit on brackets. That also keeps the room looking clean, because when the final cloth panel is in there, it will looks like this (wrng color cloth, of course...) : Completely invisible, yet still easily accessible. That space down there was originally for the sub, but you won't need a sub with these Focals, I think. Even so, you could still mount those amps to leave enough space for a sub in the future: maybe angle them inwards a bit, to leave more space but still be accessible. You could even get fancy, put the brackets on hinges, so you can swing them forward for access, or back (nearly into the hanger space under the speakers) when you don't need access. One thing you do need to be careful of, is that the amps are NOT mounted directly under the speakers: believe it or not, hot air rising in front of the drivers can have an effect on the sound. Not so much the woofer, but definitely the tweeter. It's like the way heat haze above a hot road can distort your view of what's ahead. So to it can distort the sound. OK, so the effect isn't huge by any means, but it is vaguely audible, and since we are shooting for "world class" with your acoustics, every little bit helps. So keep the amps well clear of any place where rising hot air could flow up in front of the speakers. - Stuart -

I did see that in the model but thought it was kind of a suggestion. Good point on the heat affect. I wasn't planning on putting the amps under the speakers. Moreover, I was worried about cumulative heat from the sub amps and the remote amps in a closed space like that. I was planning on using the subs with the idea that I would get more accuracy by pulling the sub 80hz stuff off of the Focal drivers. No doubt you have thoughts on that. :) what about mounting the amps on the back of the desk somehow? I want to make sure that the heat rises easily and doesn't get trapped under shelves and raise the ambient temperature of that floor space. maybe vent holes or something... I know that the subs definitely put off heat even sitting in standby. Not a lot, but if trapped it builds up. Again, I know you probably won't share my concerns...I'm a stickler for heat build up. Its a peeve I guess. :mrgreen:

I want to make sure that the heat rises easily and doesn't get trapped under shelves and raise the ambient temperature of that floor space.

Not a problem: You have that large vent "chimney" up through the entire soffit, directly behind the speaker, and your HVAC intake is right above that (the very reason I put the registers there!), so there's going to be decent convection and air movement going on. The warm air from the amps will make it's way up there easily enough. There's a clear path through the hangers, up the chimney, out the top, and into the registers. That's the way I designed it: to give you a free, clear, open ventilation path for your speakers. :) - Stuart -

So your saying that the heat from the amps will go out the side to the hangar space under the speakers and up through the chimney? hmmm...ok then. Can't be worse than the amps enclosed in the speaker cabinets! I'll go with that. Greg we have our answer. :lol:

I was planning on using the subs with the idea that I would get more accuracy by pulling the sub 80hz stuff off of the Focal drivers. No doubt you have thoughts on that.

If you really want to go for "maximum awesome", then sure! Let's add subs. By all means. However, those Focal's do go all the way down to 35 Hz all by themselves (in 3-way mode, which is what I would recommend for your room anyway), and there's not much useful stuff below 35 Hz in any case, so I'm not so sure that you need extra subs. That 35 Hz point is -3 dB, and with the soffits and my famous digital tuning I can probably stretch that another couple of Hz down, maybe even 31, with a bit of luck. That's already at the bottom end of a six-string bass with open frets: there's only two common instruments that go lower than that: concert grand piano, and cathedral pipe organ! Your Focals are VERY nice boxes! Not many reference monitors can boast 35 Hz to 40 kHz at +/-3 dB! I would suggest leaving the "to sub, or not to sub" decision until the soffits are completed (with the hangers as well), then we'll do some testing with REW and with your ears, to see if subs are necessary or not. It wouldn't be hard to add them, if needed. But I have a feeling you'll do just fine without. I love those Focals... - Stuart -

So your saying that the heat from the amps will go out the side to the hangar space under the speakers and up through the chimney?

Right! The overall airflow through your control room is: down at the rear, across the floor, and up through the soffits. Cool air descends from the registers at the back, and warm is is sucked up through the return registers at the front. So there's a natural, slow movement of air through that path anyway, plus the added convection from the heat of the amps and other gear will keep the flow moving. It's not a strong flow, but plenty enough to keep the amps happy. - Stuart -

Cool. I love them too. They're awesome! Certainly a flavor I can live for rest of my life, if I can keep them going that long. :D I already have 2 Tannoy Ts10 subs sitting around, so it won't be any added cost for those. We can certainly see where we're at as we go. I wasn't worried about the bottom end extension as much as the drivers themselves being less accurate overall with the low bass handling. It will definitely be cool to test the subs in there and compare. I have faith that those speakers are going to sound awesome on their own and be articulate of course. They already do with what we got. The room sounds loads better than when we started.

I already have 2 Tannoy Ts10 subs sitting around,

Great! So when you mount the amps for the Focals, try to leave plenty of space for those guys to fit in too. - Stuart -

The weights are: left cabinet- 36.5 lb right cabinet- 36.8 lb The amps both weigh 5.32 lb so the whole speakers still only weigh around 42 lb. The manuals claimed wight is 44 lb.

speakers still only weigh around 42 lb. The manuals claimed wight is 44 lb.

Interesting! I guess they must have changed something that lightened them up quite a bit, but then didn't update the manual. I've seen that before, so it's not all that surprising. OK, I'll start work on the calculations for the mounting system, but as we discussed a while back, the details of that will be off-line, not on-line... :) In the mean time, in addition to building the enclosure boxes, you could also build the hangers for above and below each speaker, inside the soffits. I'd really like to have those in for when we do the REW tests. The top hangers can go in now for sure, but it might be easier to leave the bottom ones out until the speakers are mounted, because you might need access under the shelves for that. You can build them all already, for sure, but only install the top ones. - Stuart -

I wouldn't want to work with the bottom ones because the shelves are going to be going in and out a few times with the speakers probably. I've got to make some extension ribbon cables for the led's. looking at making my own. I can get the cable but not sure where to get the connectors yet. Actually, I could just cut and splice in the cable skipping the connector bit. I just hate messing with the original wiring. Another one of those peeves but I probably better let that go.:)

While I was looking at the model I noticed that the passageway for heat from the amps to the space under the speakers is blocked by insulation. I'm hoping I can put a hole there for heat to pass. the insulation will definitely trap it otherwise.

I'm hoping I can put a hole there for heat to pass.

Right! I forgot to mention that. You can leave a large gap at the top, just under the window sill shelf. Maybe 2 or 3 inches high. Hold the rest in place however you want (plastic straps, wire mesh, etc.)

I've got to make some extension ribbon cables for the led's. looking at making my own. I can get the cable but not sure where to get the connectors yet.

Have you checked if Focal makes an extension kit for those? They might do. Also, make sure your extensions are low impedance (thick, low resistance, multi-core wires) similar to what is there already, to avoid messing with the electrical characteristics too much. Not a huge deal, but once again, every bit of care pays off in the end. If you can do fifty things that each only makes a difference of 1/10th of a dB, then you made 5 dB difference... - Stuart -