Sound treating a studio

Looks like [Dino] is getting the band back together. After a junkyard tube amp and a DIY tremolo stompbox, he’s back again, this time doing a bit of sound treatment in his studio.

Most rooms naturally have a bit of flutter echo. You’ll notice this when you move into an apartment or new house – rooms sound a lot more cavernous without rugs, drapes and furniture. Unfortunately, having a bunch of couches doesn’t bode well for the workflow in a studio despite what MTV Cribs may have told us. The usual solution is to put up some sound-absorbing material on the walls, and a metric ton of cardboard egg cartons don’t work.

[Dino] found a bunch of acoustic panels his neighbor threw out during a renovation (yes, we know, he’s very lucky). After doing some pre-installation tests, the panels were hung. Afterwards, the amount of echo was drastically reduced.

The good news is we finally get a look inside [Dino]’s studio. We saw the junkyard tube amp we covered earlier, but not the neat tremolo pedal he made.

Check out [Dino]’s video of sound treating a room after the break.

14 thoughts on “Sound treating a studio

  1. rehearsal? yes. Also he went expensive. wrap hard fiberglass panels or fiberglass ceiling tiles in cloth and hang them on walls to do the same thing for about $5.95 each.

    For recording, hang blankets on all the walls, or better yet record in a closet full of clothes.

  2. The timing of this is uncanny – I am looking for ways to dampen sound from my shop vac and air compressor. I wish he went into more explanation about the placement of the panels.

  3. The placement in this case is pretty straight forward. Just space the foam tiles evenly starting about 16″ up from the floor. Aim to cover 30% – 40% of the total wall area. Stagger the middle row as I did in the video. If you can, put some on the ceiling as well.

  4. Several years ago when I was researching a soundproofing solution, two sound engineers told me I’d get slightly better performance if I did not use that conical foam, or if I had it to turn the pointy ends toward the wall.

  5. turn the snares off on the drum kit, possibly even put the snare onto a towel, how can anyone be carefully listening to anything with that buzzing going on?!

    why put acoustic guitars on the wall if you want to reduce echo. the sound box will increase echo!

    why did you use a tone test? I mean you’re looking for reflected sounds.
    easier to look for echoes with shock sounds rather than long samples.

    As for placement asked above.
    just regular intervals, the point is that the large flat hard wall will reflect sounds, the foam will absorb sounds, (as the foam is not rigid) and the wavy front of the foam helps to diffuse sounds, there are still reflections, but those reflections are not as directional any more hence they won’t flutter as much and are dispersed into different direction.

    if you have enough foam to cover 100% of the wall then do that, if you have enough to cover 25% of the wall, then place the foam in intervals to try to have each area of the wall has broadly the same coverage. you’re just trying to break up the large flat surface into smaller not flat surfaces.

    Despite what the HaD article says, a metric ton of egg boxes will work ok at what it’s designed to do, which is diffusing sound.

    egg boxes are not a good sound absorber (too rigid), but they are a decent enough sound diffuser.
    (so the gaps between the foam panels could benefit from additional egg box treatment.)

    design principals of (max length sequence) diffusers states that the diffuser should be made of two strips of material, placed at different depths (ridges) where the width of the strip is half of the wavelength (or less) of the frequency where maximum diffusion (as in maximum effect at that frequency) is needed. but that at around an octave above this it will appear to be a flat wall anyway.

    speed of sound is 343m/s wavelength = velocity of sound over frequency
    egg boxes are about 4cm, even though they are spikes, you’d just model them as intersecting ridges.

    e.g. 0.08 = 343/frequency…

    so egg boxes will diffuse sounds around 4.2KHz, C(8) (and lower), but at sounds around 8KHz and above the boxes behave as a flat wall. (and reflect sounds causing echoes)

    so egg boxes are (just) OK for vocal booths, and (only just) OK for guitar and piano studios, but will do nothing to stop the echoes associated with cymbals. (which have a frequency range right up to the inaudible.

    vocal range is 80 – 1100 Hz, and the egg boxes have greatest diffusion at 4200Hz, so that’s why they are (just) OK, to compensate for the lack of performance you just use more of them. they are (only just) OK for piano or other instruments because they have a greater range of pitch, and since the diffusion will be non uniform, (max at 4200, and lesser with sounds, it’ll make pitches at the top end of the range diffuse more… -this may be desired though for a practice space where you may want to reduce brighter sounds, but wouldn’t be much good for a mix down space as you’d have an artificial reduction in bright sounds in your space, that wouldn’t be present in your listeners homes.)

    this is the same as the diffusion effect of the tiles spotted in the video though, their diffusion effect is only really good at lower frequencies. (but their absorption is better)

    if you don’t have/can’t afford sound foam then there are alternatives…

    it’s possible to coat a wall in rock wool, it’s soft enough to absorb sound, and non uniform enough to be a decent enough diffuser (especially when used in strips), but it falls apart easily. so it’s not a long term plan without continual replacement -but it’s cheap enough…

    also there is carpet, a decent pile length cord textured carpet is again soft enough to absorb sounds (though not as well as rock wool) but is sturdier, and can affix to a wall well. the corded texture helps to diffuse sounds, but, only help to diffuse the very high sounds as the spacing between the ridges tends to be small.
    e.g. carpets have ridges that are about 3mm, so the wavelength that they are good at scattering is 6mm wavelengths.
    so carpets only diffuse sound at frequencies over 34Kz well above what any human can hear. but it does mean that in the audio able range diffusion would be fairly uniform.

    Blankets are the cheapest, but probably the worst sound materials, they are soft, so do adsorb sound, (especially when hung away from the wall) but have no diffusion properties at all. blankets are cheaper than egg boxes too, so preferable to egg boxes.

    sound foam is good at absorbing, that pleases the neighbours. but diffusion of echoes is really what you want…
    that’s why if you do an image search for anechoic chamber, you’ll see that most professional set-ups (not ones that people are trying to shoehorn into houses) use deep ridged wooden wedges on the walls. you don’t want to loose the sound energy, you just don’t want it reflected in a directional manner. (you want it uniformly scattered as much as possible.)

  6. This article should be titled:

    “Dino Installs a Commercial Product”

    Whether he bought it or not, he still used the product in the manufacturer’s intention. What’s the point of this?

    If the point of this article is to spotlight the tremolo pedal, a single sentence at the end of the article doesn’t qualify.

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