John Sayers' Recording Studio Design Forum Archive

you might consider bring the front clouds down more and angling more and the overhead one a bit more as well. you can see the clouds are forcing the response to smooth out but there are are still deep nulls - 116hz in particular where the side wall response may be skewed because the measuring mic is a mono source which is narrow compared to your head which (hopefully) is much wider. so you will still need more absorption - esp when you get better monitors with better LF output. near fields tend to like the additional bass support by being closer to the front wall than not but different speakers will behave differently. peaks in LF can be trimmed by EQ to finalize the response so your mixes/masters translate.

on treatment - consider the space over the front wall-ceiling corner a candidate for super chunk trapping behind the clouds. i'm also guessing the speaker positioning needs some tweaking - i saw Eric's comments on this as well as Stewart's and with near fields which are situated in an open room, tweaking the positions as well as your seating position will make big differences. generally i like to shoot 16-24" behind the listener head but balance that with the 37-43% position and width - adjust angles of the monitors to achieve best LF and image - esp on near fields. lastly, if you are just shooting the room response, put a speaker in a low corner up front and the measuring mic on the opposite corner in the back up the room up near the ceiling - point the mic down. then run your sweeps to get the overall picture of the room and repeat this with speakers and mic on the other side so you have corner-to-corner measurements.

Once again ... Thanks Glenn for your analysis and next directions!

We are on a bit of a delay, as a number of gigs have lined up with my band and several
other groups that I've been ask to play. This has been a very NICE problem to have

In the meanwhile, I've been spending time listening to the room.

The NEXT big thing to happen will be installation of the new Mitsubishi Mini-Split system that
I have sitting in the garage. Tuesday, the installer is coming in to review the install and
see to it that we have everything needed ... looking to install Friday.

On ANOTHER front ... we'll be looking at the electrical feed into the room proper.

SOUNDMAN 2020 !!!!!

I've been following dialog in another thread where you've just mentioned the LEGRAND
conduit wire system.

This is very much the way I've been looking to go ... and will !

I do have a question on this ...

It has to do with the INITIAL penetration into the room ... and THE best way to maintain
the required 'de-coupling' from my inner and outer framed walls.

I would LIKE to keep to a single feed into the room [if possible], and then spider around the
room [this might not be too practical], as I really prefer 2 separate feeds to handle lighting
and then audio.

Again ... it's the area between the walls that I'm not clear on. Should it just be the plain
wire going through ... or should I have that enclosed, YET, decoupled [and HOW would I
best accomplish this].

Of course, this question is opened to all our experienced ones

Thanks everyone !!!

If you can, the best place to bring the power feed into the room is through conduit embedded in the floor. If not, then it will have to come through a wall somewhere, and how you do that depends on local code. Here in Chile, it MUST be in conduit: no choice. Where you live, you might have a choice about conduit or not. Personally, I prefer conduit, since it makes changing things easier in the future. If you want to run another circuit for whatever reason in a year or so, or maybe just replace the feed with a larger section because you need to draw more power, or whatever, then conduit make it easy to do that without damaging your walls or isolation at all: just pull the new wiring through the existing conduit. But if you don't use conduit, you will have to damage the walls to change anything. That's my reasoning.

But that brings up the issue of how to decouple and seal the conduit: Decoupling can be accomplished by cutting a short gap out of the conduit and wrapping that gap with neoprene rubber. Sealing the ends can be accomplished by stuffing a short length of insulation into the end of the conduit (a couple of inches) around the wires, then applying a dab of caulk over the end. That way if you ever need to pull more wires, you can carefully peel off the caulk, pull out the insulation, and proceed as normal.

Of course, your wall penetrations should also be sealed well, with putty packs, and staggered by a couple of feet to maximize isolation. That implies curves in the conduit, of course, but such is life! In other words, make the penetration of the outer leaf close to the ceiling (for example), then inside the wall cavity curve the conduit down a couple of feet, make your neoprene-wrapped gap, continue down another few feet, then curve again to make the inner leaf penetration. Or some such plan. Now, if you REALLY want to go overboard with isolation, this is one of the very, very few cases where MLV might actually be useful: you could wrap the entire length of the conduit in the cavity with MLV (except for the gap, of course), if you are really concerned about isolation... But that's probably overkill.


- Stuart -

as the hectic schedule continues ....

a brief studio update:

Patiently biding their time in the garage, we have part of the studio 'environmental control'
system. The MITSUBISHI MSZ & MUZ - FE12NA Mr Slim Heat Pump.

It delivers 12,000 BTU cooling and heating, with a SEER rating of 20.5

The inside unit has a noise rating from 19 - 45 dB(A).

This afternoon, my installer stopped by to review the site and installation requirements. He
is both a certified electrician & HVAC & plumbing.

The unit is a 220v design. From many years back we had a built in pool, with electrical
runs into the garage. This was a separate service. All indications are these lines can be
converted. One circuit converted to 220v .... the other to be routed back into the basement
to then be sent into the control room for either the audio OR the lighting needs.

We reviewed the need to seal ALL penetrations into the room, and looked at the only real
placement for the internal unit to be mounted on the back wall of the control room. This
will provide a direct run out of the control room, through the remainder of the basement,
straight to the outside unit. The drain for the inside unit will go straight to the sump pump
that is in line with the run.

To seal ... he mentioned that they usually, first, caulk the area ... and THEN apply a sealing
putty [clay]. He believes that this would also work on the holes made in the control walls.

So .... 8 AM Friday morning, the next step !

After this .... we look at the fresh air/ exhaust feeds.

Progress Report ....

Well, Friday morning came very early for me ... or it was just another late nite Thursday

Anyway ... after an hour delay, my installers came in to handle the new HVAC mini-split.

There was HOPE that a electrical outlet in the garage [that use to feed a built-in swimming
pool filter, heater & lights] was still working. To my dismay, it was determined that the boxes
had been completely disconnected BOTH at the fuse box, AND somewhere out in the yard

So .... we had to go to the other side of the house to pick up the original tap from this circuit,
and run a completely NEW line over to where the mini-split was going to be. So ... while THAT was going on, the hammer drilling through the building into the basement
proceeded. This is where the coolant lines & electrical would pass through. Of course ... hammer & chisel were involved. Inside the control room, we mounted the holding plate centered on the back wall. With the coolant lines in place, it was time to goop up the connectors & attach. Then came out several gauges, compressor, and monitor. Since these were going to test the lines for a couple hours .... LUNCH BREAK !

Returning ... all connections tested .... it was time to get the 220 line fed in. Here's the outside unit. And a view of the inside unit mounted to the back wall. With a working system, it was time to address the holes we just put in the wall.
This 'stuff' is very nice !!!

This is a dense putty, that stays flexible ... and is actually nice to work with! I was able to stuff this putty in from BOTH sides of the interior wall.
Not a great pix, but you can get the idea. These various pipes run straight into the back chunky corner trap. I'm going to have to
modify ONE of 2" wedges so that it can flush with the rest. [Pix coming soon].

Well ... considering many things, I thought we ended up with an acceptable compromise.


1st, 2nd, & third impression ...

When I went outside to HEAR the compressor ... I though it was broken or NOT working
Upon closer inspection, I could see the fan spinning ... but I couldn't hear the unit. We DID
have a slight breeze that afternoon ... and THAT was masking what noise this unit could
muster ...

Inside the control room, they had the unit running ... now THIS I was able to hear ... however
the BREEZE nearly blew my hat off ! just kidding ... they had it on TURBO mode or something.
When we set the fan speed down to MED the sound was MUCH lower ... and THEN we knock
it down to LOW speed ... the sound drop significantly. IF you listen for it, you can lightly
hear it. I'll get some measurements just out of curiosity. [it is rated at 22 dB(A)]

I must say, all in all, this Mitsubishi system seems WELL worth the cost. I'm NOT certain
how much 'heating' I'll need this winter ... but it's nice to know it's available.

PLUS ... with the 3 different filters in this unit ... the AIR quality in the entire basement
just got a whole lot better!

so much still to do ... but as of this moment .......

Good to see progress, and great that it is working so quietly!

- Stuart -

Thanks Stuart !

Always GOOD to have you looking in !!


Hey ... got a technical question regarding studio furniture ... particularly ... the DESK.

OK ... I need a plain ole desk in my room to set computer keyboard & monitor on. Of course,
this will go smack dab centered between speakers.

My question, whether I buy or build is, SHOULD I go for a desk that is, basically, OPEN
at the bottom ????? or one that is closed in around the front and 2 sides ???

My 'guess' would be, the OPEN design [basically a board on 2 support legs] and all the sides
open would be the LESSER of the evil as it pertains to room acoustics and IMPORTANTLY
sound stage imaging. [realizing that ANYTHING will cause unwanted issue].

Sure would like to hear thoughts on this !!!

Thanks!

OK ... now that the temperatures in the control room are ... in 'control'

I know need to get the next HOLE put into the walls for the electrical feed. Over this
weekend, I looking to have my electrical buddy stop in to address this.

We've been talking about the conduit through the wall [to get the feed in], and designing the
layout for the 'surface mount' conduit runs inside the room.

He is concerned about the conduit thru the wall, and the BIG issue he knows about the
transmission of sound thru these tubes. In his experience, he tells of how clearly voices
can be heard through this conduit with runs of 200 ft !!!

Yes ... understood that we can decouple inside the wall, AND that we can stuff the ends ...
however ... providing a path for the sound to travel through is making me wonder, WHY do
I even want to go that route. SURE ... we must penetrate the double walls ... I'm thinking
that we should maybe bang the conduit idea [in the wall].

I need 2 lines [1 for audio, 1 for lights] ... AND I would like, at least 1 spare. So I'm thinking
of feeding 3 lines through the walls [offset from each other], and concentrate on sealing
the holes. Since the outer wall is still without drywall installed, I can easily get to the back
side of the inner wall to get a 'double' seal. Then, when the outer drywall in place, I can
get a seal on this outer surface.

What cha think GANG !

As for the need to get 'data' lines to external servers [if going that way] ... my 'guy' does NOT
want the data and electrical together ... so we would need a 3rd hole near the front of the
room for that.

ok .... other areas of consideration/ compromise

Ceiling Treatment.

Right now I have 3 hardbacked clouds in place. As Glenn instructed earlier, I'm going to need
to alter the heights and slope angles on these for, hopefully, better performance.

For the remainder of the ceiling, the design calls for 5 more panels to go up. My understanding
is these are 'soft' broadband panels.

The dilemma [compromise].

I've been looking through the absorption charts on Bob Gold's site:
http://www.bobgolds.com/AbsorptionCoefficients.htm
and trying to balance out treatment to practicality

The 2 issues ... a door that swings INTO the room ... and ME ... walking around. We are
now in the 'traffic' area of the room [with the very limited height ... and me being of the
taller persuasion].

At BEST ... I have, MAYBE, 3" of depth to work with [before the door will clip the panel].

SO .... I realize the MOTTO ... ya gotta work with what ya have [or have NOT] ... so I need
to consult the PROS to ensure I get the best bang for the effort.

to be continued ...


.... and he's back !

so ... here's what I'm stinkin'

I have the Knauf 2'x4'x 2" panels. I can mount these to suspend about an inch off the ceiling,
maybe a bit more ... but not much.
The 'thinking' is that have some space separating the panel from a surface is better than
flat mounting. Is this correct ?

Keeping this in mind ... I know that I still need more absorption treatment. I'm particularly
looking at the side wall/ ceiling 'corners' as candidates for trapping. I can also look at the
front wall/ ceiling corner to get some trapping up there. The back wall 'may' have some
possibilities ... but I need to be mindful of the mini-split.

Anyway ... could sure use some perspective on these ideas !

Thank-you !

oh ... the question on the desk ... thoughts ?!?!

desk - consider using the smallest one possible for your gear - open as much as possible but also plan on putting an absorber on the front of it to kill off the floor reflections. plan on angling the top of it 6° if possible. consider a "mastering desk" which contains only the gear you need most and some racks symmetrically placed on either side or behind you for the rest.

on the absorption - 4" is better but 2" and hanging it down 1" may be your only option.

on the conduit - having the openings on separate sections of the walls and decoupled in the middle to avoid hard contact between the walls, as well as sealing it will work fine and allow you flexibility later.

Hi Glenn !!!

Big THANKS for stopping by [on whats' been a busy time for you]. Hope ALL is going VERY
well !!!!

Just read through your latest message. As always ... most valuable [and appreciated] information !

Between the busy band schedule [we placed in the Top 5 for the State ... our bass players'
wife made 'Runner-UP'. Personally ... glad we don't have to compete in the out of state
regionals ... just don't have time for that

I DID get to do some further work on the room

The remaining 'soft' clouds have been assembled and installed. It did have to make the compromise
at THIS point, by going with 2" panels mounted off the ceiling. And now that I have my saw back,
I'll be mounted the 2 rear wall panels [2x4' x 4"] just like the other's being 4" off the surface.
Then, to figure a secure wall to get a panel on the inside of the door ... got some ideas there.

I've NOT yet adjusted the hardback cloud depth, nor angle. I first wanted to get ALL of
your initial treatment in place, and then re-shoot the room to see what we have.

I can definitely attest to the dramatic improvement in listening just to the radio through my
very old Altec monitors. The addition of the soft clouds did a significant improvement to
the sound stage. The side phantom imaging has really come together!!!

Yes ... I figure more treatment will be in order, but it is very exciting to hear now !!!

l'll get some pix posted soon !!!

Thanks again my designer friend !!!

Sincerely.

Progress Update !!

First off ... fell behind on my 'Donations' ... was able to send a small 'token' of THANKS

OK ... it has been quite busy around here, and have had to sneak in some time for the
Control Room. The addition of the HVAC unit has been a blessing to actually be able to do
any work

A few weeks ago, I was able to get back on the remaining 'soft backed' ceiling clouds.
Had to make the tough decision, due to limited ceiling height, opting to go the 2'x4'x 2"
design for these panels. Even with this compromise, the change in the room acoustics
was dramatic !!! [in a GOOD way].

Here's the build:

Since these were thinner panels, I needed to use a different style of 'corner bead' to expose
as much of the sides of the panels as possible. I was waiting until these panels were mounted off the ceiling before re-shooting the room.
Panels are now up ... shoot to follow.

With the Mini-Split installed ... with another compromise ... I had to send the tubing into
the rear corner bass trap area. So we had to make a slight modification to 1 of the panels
in order to go around the tubes. Next event ...

Getting the electrical lines into the room.

Not much available in the picture department ... but I tried to follow all the advised procedures
to minimize flanking, and sealing all intrusions.

We ended up running lines into 2 sections of the room. One area was by the door entrance.
All surface mounts. The initial idea was to get 2 lines into each section. 1 active, the other as back-up or
addition.
Foremost, I wanted to get the box in the room and get the lines run so that I can seal
the penetration [duct clay] from BOTH sides of the interior wall. For the time being we have
an open box & a pair of outlets just to plug stuff into.

The second electrical location was in the front of the room.
Again, 2 lines brought in. These are to handle audio. All electrical holes were sealed & clayed from both sides of the interior wall.

Next up

I wanted to have a 'through the wall' conduit that would allow me to pull 'low voltage' lines
through. We did this a little different than the electrical feeds.

Again with the compromise So, with having only 1-1/2" space between the front wall
plates [dual wall] ... I wanted to run conduit BETWEEN the walls but NOT let conduit hard
connect to both walls [frame].

Ended up using 1" conduit, combined with 2 - 45* turns [to soften the angle] ... and then run
the 'split' long tube diagonal across the walls to the top area of the outer wall [again with
2 - 45* angles.
So, coming out of the inner wall: Then you can see the diagonal run. to be continued

A close up of the split section connected with a rubber adapter: Although it's difficult to see in the pic ... here is the concept that I used.

The 'rubber' adapter is the split point between both the conduit AND the wall in which they
contact. The split between the 2 pipes is ~ 1" ... the secure straps are placed so that
below the adapter is held to the interior wall, while above the adapter is held to the outer
wall. Tapping on the frames or the tubing showed that this worked well

Surprisingly ... the level of sound that travels through the tube is extremely 'slight' ....
Nonetheless ... I have another wad of duct clay to plug the holes.

While assembling this conduit run through the wall, we fed a 'pull line' using this: From the outside tube you can see the line: For now, in the control room I have the full canister sitting on the floor.

BTW .... should anyone need ...

I have 500 FEET of this pull line ... I maybe need 30' to handle more than I need.

Just let me know

Coming up ...

We have drywalling scheduled to go up on the outer walls AND, we have a qualified
assistant that I'll be helping with fabric'ing the corner trap frames AND the ceiling clouds.
I have 25 YARDS of 4oz batten and fabric.
His 'mom' is a long time seamstress ... knows the formula for 'flame retardant' treatment of
the fabric [which she is doing] as we start to make the room look nice.

Room shooting is coming up since the 'basic treatment' in nearly all in place [according to
Glenn's design] WHICH, btw ... people kinda freak the first time they come into the room

Once again ... thanks for following along with my journey ... and much appreciate the
observation from our Gurus !

Sincerely.

Lookin' good!


- Stuart -

definitely looking good! once you get the outer drywall up, thump on the walls a bit to see if you have any structure transfer (or perhaps do it now and see if you can feel it in the outside frame - probably need an assistant unless you can run really fast )