Here is an update photo of the work in progress. This shows the completed framing of the loft, with randomized spacing of blocks between the 'rafters' to prevent any resonance in the 4 foot wavelength. This will be covered with cloth and battens will hold the 4" mineral wool insulation to be fitted in the spaces. The woodwork detail on the back beam is mainly just filler, but is also adds some aesthetic value and maybe some diffusion.
I'll post another photo when the covering and battens are installed. When this is finished I'll get back to the equipment framing and installation on the front wall. I wanted to finish out the loft before doing all the work below and around it.
This photo shows the canvas covering in place with 3/16" maple paneling sheet cut into battens in place to help support the mineral wool insulation. The battens were coated on the top with diluted carpenter's glue and stapled in place after spraying the joist area with water to help the glue diffuse through the cloth and into the joists. If high frequency reflection off the battens is too bright I can cover them with absorptive material.
Next I'll cut and install the insulation, then install the floor panels on top of more 1/4" foam rubber pads to maintain structural isolation. There is also a safety rail and ladder system to finalize in detail.
To recap this phase: This loft is to provide sleeping space while freeing floor space. Insulating under the flooring is first to avoid a cavernous sound effect in the primary listening position below. This and the 4" foam mattress on top should also help with vertical and transverse resonant modes in the 40-50Hz dimensions of the room, and hopefully also in the horizontal plane by relation. I'm working first with the necessary and will resolve what is actually sufficient as I go.
This is a dual-purpose room; it is a music studio and I may be able to express some character in such a small space, with the right attention. It is also a production/listening room. This means I will accept the acoustic character that may develop, while keeping out extreme anomaly that can get in the way of accurate listening. What I mean is that I may be able to get a big room sound in a small space. A sound absorbing wall can be seen as pushing the wall back so many feet for each drop in dB of sound pressure. We'll see how this room tunes.
Last edited by fractile; 09-08-11 at 06:33 AM..
Reason: added recap
Adding the insulation in the loft/baffle has really focused the sound. I can't wait to do the same to the front wall behind the speakers.
Early on it was advised that I use a lot of sound treatment. I was reluctant due to space and expense and purist concerns. However, there are practical issues that need addressing and become more apparent now.
A side effect of isolating the room from disturbing neighbors is the focusing of the sound in the room. I am trying to achieve a balance and keep enough liveness in the acoustic. It seems like a soft expansion of the sound without slap-back and blur.
Here is a new post on my slow as molasses progress:
You can see we're back at the front wall. I am about to frame in and cover 4" of mineral wool with a cotton decorative quilt. At the same time
i will build 3 shelfs; the top one is for general A/V playback; below that is space for 2 subs and a center co-ax speaker that i have drivers and material for. Below that is the main monitors sitting beside the central 32" video monitor. I have worked out some positions for the kdb and controller... more later on that; here is a pic to recall:
I planned to post this in red as a disclaimer; n/m; the reason for all the detail is to maybe help people building microstudios. I 1/2 intentionally posted wild speculation in part because I wanted to express ideas I think about and also to get others thinking.
If you want to see a fullblown studio look at manifoldrecording.com
That is how things are done from scratch. How I am building is a small sliver of that; it is from scratch in a very small space and on a crazy budget.
I had some money to invest in all new eqpt. I imagine most people in this situation would be evolving a given set-up. My idea here, is that if someone wants to evolve a professional studio, it requires some thinking about the concepts around foundation and workflow. The foundation is the architecture and acoustic and the workflow is the installation layout of equipment, especially in a limited space.
There can be anyplace to enter into professional audio these days. In the process it is good to understand how ones system relates with a reference.
I have seen some recent talk about it is only the production as art that matters. There can be errors in this disregard of fidelity. I say this because I have heard some attempts at distortion that would drive Jimi Hendrix crazy.
Maybe I can say to record the cleanest signal you can, even if overdriven.
Last edited by fractile; 11-14-11 at 05:40 PM..
It' time to update the situation, here. I'm back on the front wall, as seen in post #3 and the one previous to this one, and have installed 4" rock wool 8 feet wide and 6 feet tall. I want to mention that rock wool is fairly easy to work with, that cutting it is literally easy as cake. However, it is also like brittle fiberglass, so you might want to wear gloves. Also, it should be covered with something to keep fine dust particles from escaping.
The first photos show how the electrical stuff, AC outlet, light switch and doorbell was redirected from the wall to make the acoustic isolation work better and not allow sound to leak directly into those foundation wall penetrations. It looks a little primitive, but my main concern here is with structural integrity using materials at hand. In the second photo you can see a ground wire coming from the bottom of the outlet box. This goes to the cold water pipe under the kitchen sink. None of the outlets here were grounded; this building was constructed in 1929 and the electrical system is from that era. The next two photos show the whole wall with insulation installed.
After that is the completed construction covered with a 1/8" thick quilted cotton. The detail shows the electrics mounted on a type of fascia that trims out the covering and also bridges the insulated gap between the 1x4 insulation frame (made from 1x6's ripped down to 1x4) and the H-frame 2x6. The flexible conduit made it fairly easy to staple down the edge of the covering, then secure the fascia with brackets.
I've about figured out construction details of the next phase of equipment shelving and hope to complete that this week. Then, a permanent-type equipment installation can begin.
p.s. After this additional expense and effort I should mention the actual result this achieves. The immediately noticeable result is to isolate the speakers from interaction with the room, removing a very large percentage of resonance with, and reflection from, the hollow plaster wall behind the acoustic panel. This prevents sound from traveling throughout the rest of the building and also from the building next door, since without the insulation the room is a big resonant box, essentially amplifying the sound from the speakers and radiating it into space.
On the other side of the equation, the sound becomes more accurate to the source (within the limits of the speaker system). But then, the amplifier has to be turned up higher to get the same sound levels as before; along with all that is the benefit that even with higher sound levels coming from the speakers, it does not sound as loud "in the room", since the main portion of the _effective_ sound is going to ears and not walls.
There is still some treatment to be done on some doors and miscellaneous etcs., but along with the horizontal plane of the loft baffle things are well on the way to being contained.
Last edited by fractile; 02-21-12 at 05:21 PM..
Reason: Note on acoustic effect.
I'll post some comment between photos add detail: I just red most of the book, The Studio Builder's Handbook from Owsinski and Moody. The mention of steel versus wood studs got me thinking about material properties.
My impression is that softer woods tend to absorb sound and begin to resonate by reradiating the frequencies associated with their dimension. I imagine that maple is the most often used wood in sound studios, because it is dense and less absorptive, therefore less resonant.
Building a dedicated studio has more freedom to develop a signature sound; a studio in an apartment building has limitations. People will discover the limitations in the process, now I encourage people to thing ahead a few steps before imagining that acoustic isolation is secondary.
Back to the present, steel has less acoustic energy storage and is quieter than wood, in my estimation (I don't have numbers to prove it). For the urban scrounger, there is square metal tube and angle-irons of various dimensions to be found; various bedframes can supply this, with 1.5mm, 1/8" and larger thicknesses. It might take a few years to collect.
If you are serious about having a music studio for both electronic and acoustic instruments, then attention has to be aware of the nature of sound as a fluid that will flow where it can. You do want to have a quality of sound in whatever room you have, but the boundary of the room has to deal with how the sound escapes to everyone else in the building's ears.
The building I'm in, on the top 3rd floor, was built in 1929, with shoddy maintenance over the years; so anything i do is an improvement. My suggestion at this point is to know how far to keep the lid on and work continuously to adjust your schedule during the day when everyone is at work and also seal up the space within your limitations of modification. Expect to pay as much on isolation as for a good piece of gear. And think about it early, before building in equipment on top of where some isolation should have been.
Note: While it's on my mind I can add some pointers that may help; this is my first attempt at professional-level production studio assembly, even if I have previous construction and audio experience.
Work out your workflow and where it may go in the future; do as much prototyping of the layout and construction as possible, before nailing things down. This can help to maximize the future-proofing of the studio. Prototyping and thinking through will help prevent false moves in the construction. The tape measure is your friend; things that begin with foot or inch measurements eventually get down to fractions of an inch when maximizing space when building in to maximize floor space, especially. Learn to understand the balance of ideal and practical.
Probably the most neglected yet sometimes most important is acoustics; what is called sound control, both isolation and tuning of the space. Every space is different; some may have concrete floors and insulated walls to begin with. At any rate, I've been working incrementally, first on the necessary architecturally structural elements: The front wall is hollow plaster; plaster of paris coated on grout, with redwood lathing and framework. I had thought I could, naively, put a 5/8" wood-fiber sound batt under 3/16" of HDP to attenuate the sound while maintaining the character of the space. You can see from the previous photos and descriptions where that goes.
What I want to mention now is "flanking sound". Working a lot with sound, the ears become sensitive; a microphone doesn't have this learning curve and still hears more than you. Ok, depending on where you start, the weakest links are something to look at. Caulk all cracks and seams with something resilient. By the way, this is for a studio that might be working with live recording and/or playback on loudspeakers. It can get complicated, but I'll just cover some basics. I have a front door on this top 3rd-floor 1929 apartment that I assume is made of thin redwood panels inserted into the ~2x door. Anyway, i ordered some "Frost King V23WA Extreme Rubber Ribbed Weather-Strip Tape 3/8-Inch by 1/8-Inch by 17-Feet, White" to put where the door meets the jamb. For more isolation I can add some V-fold tape between the edge of the door and the frame. Test and observe...
Last edited by fractile; 03-23-12 at 08:19 AM..
Here's the latest photos, getting down to furniture layout and power distribution. To the left (in the first photo) is a 5 foot wide by 30 inch deep Steelcase table I found on the sidewalk; very sturdy work table. I cut a few inches off the legs to get it down to the more casual work-level height that I've adopted. I intend to add a slide-out shelf under the top, to put a MIDI kbd/controller.
If you look close you can see a standard power outlet and three power strips. This is because power distribution comes out of a power conditioner with plain analog power on 6 outlets, and also a bi-directionally filtered set of 6 outlets for digital equipment and other noisy electronic power supplies. The silver strip has 16 outlets for analog gear and the white strip up in the left corner has 6 outlets for digital, that can be expanded to 18 with the 3x1 adapters that can be seen. The blue strip to the left is for a set of 6 switched outlets for power amps, etc.
In the center photo, below the video screen is a bridge across from the table to the stand. This is where the DJ mixer/sequencer is planned to go. The video screen can also be used as a monitor for the computer control screen.
On the right (third photo) is some stuff in transition. The mixer, I intend to install in a slightly mobile rig, to allow moving from the center of the room to a listening position behind that; possibly by rotating 90 or 180 degrees. I still have to design that, to include room for stereo EQ, compression, dynamics and recording outboard gear, plus possibly some patchbay.
And... on each side of the video monitor is space for ~12U racks of a very simple open-air design; I don't have an air-conditioned equipment-cabinet installation going on here, so leaving everything mainly "open-frame" helps allow good air circulation. Excessive heat tends to shorten the life of electronics.
That's about the extent of progress. I'm trying to get the main foundation set and begin installing and working with equipment; otherwise it could end up in endless digression. And then there's the fact that any work on organizing the space pushes all the equipment further into corners of this tight space, until it can be installed in it's space-saving final location...
Here's another in the series of sudden changes at the last minute; one reason I'm glad I take my time.
I recently salvaged some JBL 8330's from the dumpster of a movie theater. They're THX certified and are already built; good thing I had set aside my custom speaker project on the JBL L-77 boxes, in favor of doing peripheral work around the edges.
The speakers are shown in the photo, sitting on their side, and by measurement they fit the space shown above them with 1/4" to spare. With a shoehorn they fit.
I'd been thinking of how to install adequate support to hold them in place when I noticed what I'd call excessive flex in the 1-1/2" angle-iron crossbeams supporting the equipment above. The violet horizontal line is one of the angle-irons. The big reason for this is that the only support for the beams is at one point on each end, plus there will be some flex in the steel vertical-frame support on the right.
My solution to this is installing some 1" angle-iron braces to triangulate between the top beams and one below them in the back (hidden behind the tan maplewood beam horizontal that I have since removed with two bolts; it becomes redundant.) This, along with additional structural isolation will keep most of the vibration of the speakers from reaching the playback equipment in adjacent attached spaces. The front-end gear below that is on a separate support structuring.
The dark line dropping down from front to back and its first shadow hint at where the braces go. I've marked the metal stock and will attempt to do the cutting and drilling this week; and install the monitors, as well. The front-to-back diagonal is also an integral support for one side of the speaker mounting. The boxes have some versatile threaded mount-points.