Echo Bar Recording Studio Build Diary

You could have done it from your side quite easily, without bothering your neighbor at all: Just beef up between the studs. That's a commonly used technique here on the forum, for cases like yours.

This is why I regret that I waited to post this journal on the forum until after the build was completed. You are absolutely right Stuart. I didn't think of that. Hopefully, others will learn from my mistake(s).

I'm just wondering why you did that: Was the floor especially uneven, and needed the extra seal? Also, fro the photos it's not clear how you attached the wall frames to the floor: I don't see any bolts visible, so I guess you just used nails. But it looks like a concrete floor, so how did you accomplish the nailing? You DID attach the walls to the floor, right?

Yes, the concrete was uneven in many places and I chose to use the neoprene to seal even the smallest air gaps between the sole plates and the concrete. Yes the sole plates were all nailed to the concrete floor with galvanized nails. This was required by the city inspector. The were driven through the plates into the concrete with the "explosive nail caps". I am sure there is a more technical name for this tool but I don't know what it is? My framer did let me "fire" one of the guns. It is actually like firing a real pistol and just as dangerous.

Here is a shot of my control room door opening. This is Control Room B and Booth B.

Yes, the concrete was uneven in many places and I chose to use the neoprene to seal even the smallest air gaps between the sole plates and the concrete. Yes the sole plates were all nailed to the concrete floor with galvanized nails.

That's what I figured. You did fine. some folks use neoprene thinking it will "float" the wall, but of course it does not. As soon as you put the first nail / bolt in, that creates a flanking path right through the neoprene. But you did it as a seal for an uneven floor, which is the right thing to do. Great! - Stuart -

These next photos are of the Live room framing going up. This a shot of inside the Live room with Booth A on the right.

This is a shot of the live room ceiling joists going up. They span a width of 25'. These joists are Douglas Fir type #2 as required by my architect and structural engineer to withstand the load that would hang from them. They support 2 layers of 5/8" drywall with green glue. The entire studio was framed out in 4 days. I took a photo with the crew on the last day.

We passed the framing inspection and were given the go ahead to start electrical. Here is a shot of my electrician chalking out where he will put the can lights for the live room ceiling.

We replaced the florescent lights in the lobby/lounge/kitchen with incandescent. In the meantime I built my microphone panel boxes. You will notice that each panel has duplicate jacks above and below. 1 set is for my control room and the other set is for my partner's control room.

Here are shots of the insulation going in the walls.

Nice mic panels! :) Looking at the lighting you did for the control room, I'm wondering how you isolated those cans after you cut the big hole in the ceiling? Did you build boxes around them from above? Not clear from the photos. - Stuart -

Sorry I've taken a while to up date this. I've been very busy actually doing sessions in the new studio.

Here is the first of the Drywall being delivered. And More Drywall. We used 5/8" thick type X Drywall.

Here is some of the first layers of drywall going up. We used backer rod and OSC 175 Acoustic caulk in all the seams to make things air tight.

1st layer of drywall in live room going up.

We used green glue in-between the 1st and 2nd layers of drywall.

Its also worth noting that in-between the 1st and 2nd layer of drywall I layed down the hardwood floor. This allowed for a better seal between the 1st and 2nd layers of drywall. I used backer rod and caulk again. Above, these photos are of the live room floor going in. Above this is my control room floor going in. 2nd layer of drywall going up.

The next set of photos are of my Control Room. These will show how I chose to treat my room acoustically. I spent a lot of time planning my room design. Somewhere on this forum someone stated that, "You should design your room around your speakers." Or something very similar to this. My apologies for not remembering who said this. And my apologies for not quoting you exact. But, I really connected with this statement. I bought my speakers well before I designed my room. My main speakers are Dynaudio Air 25's with 2 x Air Base 24's. I also have a near field pair of Dynaudio BM5a's. So, I designed my room with these speakers in mind. As I stated earlier in this journal my control room dimensions are based on the Sepmeyer ratio. A couple of details you will note are that I chose to soffit mount my speakers. I also chose to angle them in 60 deg and down at 10 deg. The speakers' height is specific to my body height and where I wanted the listening position to be in the room. These angles and speaker height allow my listening position to be within the 38% rule in my room which has a length of 21', width of 14' 4", and a ceiling height of 9'.

These next photos are of the side wall and back wall construction of my Control Room. This is the start of the back right base trap in my back wall of my control room. This is a modified design based on Ethan Winer's sealed panel traps. This photo is of a 2 pieces of 2 inch thick rigid fiberglass straddling the right corner of my back wall. What is not clear in the photo is how I attached it to the wall. What I did was to rip a 2x4 at a 45 degree angle down the length of the board. I bolted these two haves to the drywall thus making a frame to screw the insulation to. I used fender washer to keep the screws from pulling through insulation. Then I ripped another 2x4 and screwed them to either side of the insulation and made a new frame to attach the wood panel to. This I glued with wood glue and sealed with acoustic caulk around the perimeter of the 2x4's and the drywall. I cut a triangular top cap to place on top of the trap which I glued and screwed into place. The idea behind these traps is to make sure they are sealed air tight. You can see the caulk in the photos.

This next photo is of the the side wall of my control room. It shows the frame work I built for the insulation and fabric cover. This framework allowed me to leave an air gap between the insulation and the drywall. The insulation is once again 2" thick. Here is a photo of the opposite side wall and the entrance into the control room. It should also be noted that I had my electrician surface mount all electrical outlets and light switches. This prevented any major holes made in the drywall.

These next photos are of the continuing construction and treatment of the Back wall of my control room. In addition to my corner panel traps I also added "hanger" base traps as described by John here on the forum. They are made by sandwiching a piece of sound board i.e. (homosote) between two pieces of fluffy fiberglass insulation. They are then hung from a frame work and thus suspended off the floor. In the middle of my back wall I chose to put more absorption. What you can also see in these last photos are the mounts for the diffusors I built. They are "french cleats". It was the best way that I could figure out to mount both of the extremely heavy diffusors on to my back wall frame work. here is a detailed design of the french cleat method I used. This was exciting to finally mount these diffusors onto the wall. Sorry for the blurry Photo. There are better photos later on. I should also mention that I mounted these at a specific height to the advantage of where my tweeter and mid range driver of my Air 25's are aimed in my room.

"You should design your room around your speakers." Or something very similar to this. My apologies for not remembering who said this.

I think that was me! At least, that's my philosophy, but I bet I'm not the first person to say it, so I can't claim copyright! :) Anyway, a few comments on things I noticed in your photos:

This is the start of the back right base trap in my back wall of my control room. This is a modified design based on Ethan Winer's sealed panel traps.

Panel traps have to be sealed, yes, but I don't understand how yours will work, since they seem to be angled across the corner, and therefore the cavity depth is not constant: So how is that going to work? What frequency did you tune them to? I'm not aware of any theoretical basis for how such a trap would work, or how you would go about tuning it, so I'm intrigued about how you did that! Maybe you could explain?

In addition to my corner panel traps I also added "hanger" base traps as described by John here on the forum.

Hangers are great, but yours seem to be touching each other, so they won't be working too well either. You might want to try strapping thin insulation closer to the board, so that they don't touch each other. Maybe wrap them with wire, or some such. Unless the hangers are able to swing freely, with air gaps between them, then they'll just act like expensive absorbers, not like hangers. You also should put some absorption on the rear wall, behind the hangers. That's part of the system.

This was exciting to finally mount these diffusors onto the wall.

Are those N7 QRD's? Looks like they might be. What is the low frequency cutoff for those? Looks like they go down fairly low. Also, you never did answer my question from back in November, about how you isolated the light cans after you cut the big holes in the ceiling drywall. - Stuart -

Hi Stuart,

Panel traps have to be sealed, yes, but I don't understand how yours will work, since they seem to be angled across the corner, and therefore the cavity depth is not constant: So how is that going to work? What frequency did you tune them to? I'm not aware of any theoretical basis for how such a trap would work, or how you would go about tuning it, so I'm intrigued about how you did that! Maybe you could explain?

Well to be honest, I did not create them to be tuned to a specific frequency. The way that I understood Ethan's panel traps to work were more across a range of frequencies. Perhaps I misunderstood his design altogether?! :shock: He had several designs that he labeled "low frequency" ,"low mid", and "High Frequency" absorbers. He never specifically stated which frequencies they were "tuned" for. It was my understanding that they were effective over a range of frequencies not tuned to a specific frequency. Perhaps I am wrong?! Regardless, I can attest that they are quite effective at smoothing out the low frequency response in my room. I have measured my room's response and am quite pleased with the results.

Hangers are great, but yours seem to be touching each other, so they won't be working too well either. You might want to try strapping thin insulation closer to the board, so that they don't touch each other. Maybe wrap them with wire, or some such. Unless the hangers are able to swing freely, with air gaps between them, then they'll just act like expensive absorbers, not like hangers. You also should put some absorption on the rear wall, behind the hangers. That's part of the system.

Once again this is why it is important to post while you are building. I hope people will learn from my mistakes. Even so, as I mentioned above the low frequency response in my room is really great.

Are those N7 QRD's? Looks like they might be.

I don't know what N7 means?! Please explain. My diffusors are custom QRD's. They have a low frequency effective range of 800 cycles and a high frequency effective range of 6700 cycles.

Also, you never did answer my question from back in November, about how you isolated the light cans after you cut the big holes in the ceiling drywall.

Yes, sorry about that Stuart. I overlooked you question. Those light cans are in the live room ceiling not my control room. I thought about using "putty pads" as are commonly mentioned around here on the forum but in the end I chose not to. They are not sealed other than some caulk around the rims where the can meets the drywall. Mistake? Perhaps?! But I have not had any isolation issues in the live room. Perhaps the distance from the live room to my control room makes a difference?!

The next set of photos are of my front wall in my control room. Once again here are some custom panel traps that I made in the corners of the front wall. Next are photos of the stands I made to hold my Air 25's. These are concrete blocks that I mortared together and filled with concrete. They are very heavy. The speakers are in custom boxes that I built out of 3/4" MDF. These MDF boxes sit on top of the concrete stands. I put a piece of 1/4" Neoprene on top of the concrete blocks before I fit the speaker boxes on top of the concrete stands.

Next I began to frame out the front wall. I made sure to build a frame work around the speaker stands and boxes without actually touching them. I also put some more hanger bass traps around the speaker stands.

I added 3 layers of drywall to the frame work around the speaker boxes. You can also see the vent holes at the top of each wall for my speakers. My speakers are active speakers. Next I made the frame work to mount my Monitor screen to. This is a photo of measuring out the cloth that will be attached around the face of the TV frame

These next photos are of the wood paneling I cut and stained to finish off the front wall.