Author Topic: Best value acoustic treatment: uthermo, energylite, insulboard, 25, 50 or 100mm  (Read 921 times)

Offline nicklear

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I'm looking for the best bang for buck in setting up acoustic treatment for a charity project.

From previous threads and other users, the main options seem to be uthermo, energylite or insulboard. Densities are ~ 40,60,80 & 100 kg/m3.

This spreadsheet (thanks to @Abu) https://docs.google.com/spreadsheets/d/1U-kh6dxTB7cJiDh8z2uyQrxbDQxSq1n5hxvhkHwTI3I/edit#gid=0, suggests the prices of all boards are roughly proportional to the weight of the board (~R1 per kg/m3 for each 25mm), with the exception of the insulboard being a bit cheaper, but it being only 80kg/m3 and up.

Looking at the research online for Corning 705 (96kg/m3) vs the 703 (48kg/m3), it shows that there isn’t much advantage in using the 705 in general & only marginal gains for bass traps (enough for people to use it if budget allows though & it does more with less space used up). “705 is a little better but it costs twice as much” and “it's better to have twelve thinner panels spread more completely around the room than only six thicker panels covering less total surface area” [Winer]. (Sources: http://www.bobgolds.com/AbsorptionCoefficients.htm, https://www.gearslutz.com/board/bass-traps-acoustic-panels-foam-etc/76001-703-705-alternatives-acoustic-traps.html, http://ethanwiner.com/density.html) The figures for Roxul are similar.

So if the fibreglass or rockwool here follow the same trend, the Uthermo 3 (40kg/m3) or the Energylite 47.5kg/m3 would make the most sense. And acccording to Winer, spreading however many sheets I can afford around the room is best, but I'm not sure which of 25 or 50mm would be most efficient use of funds. For bass traps, the most economical I've found is the Studiotips Corner Absorber design (http://forum.studiotips.com/viewtopic.php?f=8&t=534) where they use 100mm of 703 density across corners.

Can anyone give any feedback on this in terms of anything I’m missing or their experience with any of these options?
« Last Edit: December 30, 2016, 09:22:34 PM by nicklear »

Offline Abu

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Hehehe, I'd forgotten I'd setup that sheet. I wonder how much the prices have changed

PS. What is the aim of your treatment? What "artifacts" you want to address?

Offline nicklear

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It's really helpful to have it - when I get current prices I'll write them up in this thread.

I'm setting up a music studio in 1 or 2 rooms. So early reflections, flutter echo, reverb & might use moveable panels to act as a gobo or portable vocal booth. Both rooms are small - ~ 3mx4m. Monitors are small too - 5" Tannoys which have limited bass which I think is helpful in a small room.

Most of what I read on the web is aiming for the best, which is great if you can afford it, but I think I can get decent results with recording and mixing with a fair few panels, a bit of diffusion & whatever blankets etc I can find.

Some questions I have:

- Do any of the suppliers in Cape Town supply low quantity or does it always have to be a group buy?
- Some, e.g. the studiotips guide, claim you need twice the density of rockwool/mineral wool to be equivalent to 703, others have it performing close, what's right?
- A lot of people use uthermo 8 instead of 3, is it worth it if cost is a primary concern?

Offline nicklear

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Still keen for any feedback from those who've made absorption panels.

Also, in terms of sound isolation, I've been reading about resilient channels or green glue to de-couple the drywall. I can only find these as imports which are expensive and long delivery times. Anyone found something like this?

Offline Rotten Johnny

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If you wait a few months I'm likely to have four Uthermo chunk traps, some diffusers and a bunch of absorption panels up for sale.
Audiophile: There is almost no other group that prides themselves more on wasting good money on utterly worthless ****, and then trying to furiously blow smoke up their own ass to justify it.

Free your mind...and your ass will follow.

Offline nicklear

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If you wait a few months I'm likely to have four Uthermo chunk traps, some diffusers and a bunch of absorption panels up for sale.

I'm actually looking to build this month. Would you say the Uthermo 3 (40kg/m3 I think from another thread) is roughly like for like to OC 703?

Offline Rotten Johnny

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Probably not, for bass traps I'd use Uthermo 8, and for absorption panels Uthermo 6.
Audiophile: There is almost no other group that prides themselves more on wasting good money on utterly worthless ****, and then trying to furiously blow smoke up their own ass to justify it.

Free your mind...and your ass will follow.