endorka wrote:Source of the post Sorry to hear about your knee Sam, all the best for getting that sorted.
These silencer dimensions look good, nice one. How many baffles will you fit in these?
Thanks for the kind wishes, and assistance!
As I plan the boxes to be 2400mm in length (same as the length of the OSB boards I have to make life easier) and 520mm wide, I see that as per Gregwor's silencer design calculations:
Y=520mm = 20.4”
X = (Y - 7) / 2
= (20.4 - 7) / 2
= 6.7”
6.7” = 170mm
If I divide the box length by 170mm (rough calculations) I get 14. The liner will take up space so I'm thinking 13 baffles. Let me know if I have that wrong.
Glenn is correct about the location of that long pipe. What material will you be using for the correctly sited pipe by the way? I used 150mm diameter insulated flex duct for the equivalent duct here, with the notion it would decouple the outer leaf and fan from the silencer. I used the non perforated type. You can get perforated types that apparently have better sound attenuation properties, but those are not to be used in potentially damp spaces e.g. lofts.
Yes, I will be putting the outlet from the box directly in the room and having the long pipe going to the outer leaf/fan.
I'll be going on what you have recommended; the 150mm flex duct - This stuff looks great!
https://www.justfans.co.uk/acoustic-alu ... -p-71.html - It will be situated in under the 'warm roof' so should not get damp.
Do you have a way of assessing the amount of fan noise you'll end up with inside the studio before covering the works in plasterboard? If this is potentially a concern it might be worth attempting. Glenn has mentioned building a silencer style box around the fan itself to reduce fan noise. This is something I would do if I had space, but it may not be necessary for your requirements.
Unfortunately not. I am happy to proceed and just live with the end result. If I get the quietest fan I can it should mitigate noise from that at least. Plus it will be me on my own for the majority of the time so can have low speed on the fan. Getting to a point where I need to get the project done asap. Once I have my knee op I'll be out of action for a while again.
Another consideration is the location of the silencer opening into the room. I had no choice other than to place mine near the tri-corners. I wonder if this amplifies low frequency sounds coming out the opening (e.g. fan rumble) in the same way it does when you put a speaker in a tri-corner? I've no idea if I'm putting 2+2 together here and getting 5, but it might be worth considering placing the opening away from a tri-corner.
Yes, I have thought about this. as the boxes are near the front right/rear right of the room (facing mixing position) I can have the outlets in the corners.
Remember to size all ventilation grilles etc. appropriately to keep static pressure manageable.
I assume you mean to keep the 150mm diameter with all duct and grills etc?
Will you be using positive pressure (fan blowing in) or negative pressure (fan sucking out) ?
I'm not sure what is best tbh. I don't want the cold air coming in over the mixing position, and as the fan will be situated over the door, rear right corner, I think pushin in the air on this side so that air is sucked above mix position is best.
on the fan - i prefer to have them outside the room and push and pull (supply and return) so the fan noise is part of the attenuation of the silencer job rather than in the room. but it will depend on your option to maintain them (fans need cleaning, or go bad) and if they're buried in the unit or inside the structure then maintain them becomes a problem.
Thanks. I plan to have the fan connected to the outer leaf under the roof on the outside of building (protected from the elements and accessible), basically the same as Gareth's room; we have an identical roof design:
As my fan will be in the same position as above, is it worth the extra expense of the Fan you have suggested, Jennifer (
https://www.justfans.co.uk/silent-500150-p-1906.html) over Gareths one (
https://www.justfans.co.uk/td500-mixven ... p-202.html)?
It's only £50 more but the difference is 27dB vs 35dB respectively (on max speed) I guess in the grand scheme of things a quieter fan, even if only by 8dB is probably worth it; what do you guys think?
Also, does this fan accept the speed controller (
https://www.justfans.co.uk/speed-contro ... p-656.html - love the look of this bty, perfect for the soviet-style studio
, Jennifer? I can't find that info...
Thanks again for the support on this stuff!
Sam,