Studio build in Wales, UK...again!

[Paulus87]

Is anyone out there?

This place has gone awfully quiet during lockdown, I hope everyone is well and safe...

Paul

[Paulus87]

So I just thought I'd mention on my thread that the improvements to Gregwor's TL calculator implemented in version 2.05 really make a huge difference to previous calculations!

A somewhat depressing difference. I thought I was going to be getting decent isolation all the way down to 20hz but looks like this is near impossible using timber frames.

So, anyone who has previously used an earlier version of the calculator may want to re-evaluate their design using the newer version found here:

https://docs.google.com/spreadsheets/d/ ... 1543869474

Paul

[John Steel]

Hello there Paul,

This place has gone awfully quiet during lockdown, I hope everyone is well and safe...

I'm still clinging to the perch thanks! I've been concentrating on my build for the last few weeks and it's coming along steadily.

I just thought I'd mention on my thread that the improvements to Gregwor's TL calculator . . . really make a huge difference to previous calculations!

Dead right! I ran my numbers again and it persuaded me that I should increase the gap between my leaves. Best wishes to all & stay safe.

[Paulus87]

Hello there Paul,

This place has gone awfully quiet during lockdown, I hope everyone is well and safe...

I'm still clinging to the perch thanks! I've been concentrating on my build for the last few weeks and it's coming along steadily.

I just thought I'd mention on my thread that the improvements to Gregwor's TL calculator . . . really make a huge difference to previous calculations!

Dead right! I ran my numbers again and it persuaded me that I should increase the gap between my leaves. Best wishes to all & stay safe.

Thanks John, glad to hear things are progressing for you, that's great news.

Yes regarding the MSM calculations... it's a pain in the butt, care to share what your TL graph looks like? Or is it on your thread already?

I am contemplating building the rest of the studio with concrete blocks now, seems to be the only way to get decent low frequency isolation in any case. Or perhaps I will just have to settle for compromised isolation below 40hz.

Paul

[John Steel]

Hello again Paul,

care to share what your TL graph looks like? Or is it on your thread already?

No, I never have posted a T/L graph and I haven't updated my thread recently either, but when I used the calculator recently it offered these results assuming an inter-leaf cavity of 200mm (as originally intended).

200mm.png

Increasing the gap to 300mm improves low end isolation slightly, but there's still an uptick in sub bass frequencies

300mm.png

and the curve doesn't flatten out until the gap is 400mm (!).

400mm.png

However, I don't know how the fact that most of my outer leaf is actually single tier brick will affect this. I based the calculation on the least dense materials in the outer leaf (12mm cement board and 18mm OSB) because the overall isolation can only be as good as this. Additionally, because three of the outer leaf walls are formed of bricks, this will impact on the efficiency of the MSM system, which are known to work best when the mass of both leaves are the same. Looks like I'll never be able to play 5 string bass through an Ampeg stack in there! ATB JS.

[Gregwor]

Is anyone out there?

This place has gone awfully quiet during lockdown, I hope everyone is well and safe...

Sorry I haven't been around as much. I've been super busy doing everything other than building my studio or spending hours everyday on here. I WISH I was doing that. Instead I've been trying to get as much landscaping stuff done while I'm not working much. Also, we just bought a new commercial space for my wife's hair salon (there goes a bunch of my studio build out savings) so soon, I'll be busy as hell renovating/building that out. I'm glad to put my money into her business though as it actually makes us decent money as she has employees unlike my businesses.

Also, now I'm taking care of her and the kids as she has a really bad flu! I'm pissed off because it seems no one around here is wearing masks or keeping their social distance and the masks we wear everywhere protect them from us, not the other way around. So, we have our Covid-19 tests booked for a few days from now. I pray that we don't have it.

Anyway, so I'm stuck inside with the family again now so I might have some more time to be on the forum.

So I just thought I'd mention on my thread that the improvements to Gregwor's TL calculator implemented in version 2.05 really make a huge difference to previous calculations!

A somewhat depressing difference.

I apologize for the more accurate calculations haha It just goes to show that physics are a lot less friendly than we want them to be. I'm just glad I'm not working at SpaceX trying to design something to get us to Mars!

Greg

[Paulus87]

Is anyone out there?

This place has gone awfully quiet during lockdown, I hope everyone is well and safe...

Sorry I haven't been around as much. I've been super busy doing everything other than building my studio or spending hours everyday on here. I WISH I was doing that. Instead I've been trying to get as much landscaping stuff done while I'm not working much. Also, we just bought a new commercial space for my wife's hair salon (there goes a bunch of my studio build out savings) so soon, I'll be busy as hell renovating/building that out. I'm glad to put my money into her business though as it actually makes us decent money as she has employees unlike my businesses.

Also, now I'm taking care of her and the kids as she has a really bad flu! I'm pissed off because it seems no one around here is wearing masks or keeping their social distance and the masks we wear everywhere protect them from us, not the other way around. So, we have our Covid-19 tests booked for a few days from now. I pray that we don't have it.

Anyway, so I'm stuck inside with the family again now so I might have some more time to be on the forum.

So I just thought I'd mention on my thread that the improvements to Gregwor's TL calculator implemented in version 2.05 really make a huge difference to previous calculations!

A somewhat depressing difference.

I apologize for the more accurate calculations haha It just goes to show that physics are a lot less friendly than we want them to be. I'm just glad I'm not working at SpaceX trying to design something to get us to Mars!

Greg

Hey Greg,

Good to hear from you again, for a minute I thought you had left the forum

Glad to hear you're doing well despite the delays to your studio build, it's kind of the same for me here.. got to prioritise other aspects of life during this time.

I would appreciate your thoughts on my design concept on the previous page of my thread (18). The idea is to have as large a ray free area as possible, as I would like to have two other listening positions apart from the main position at the console. Take a look if you get a chance!

Cheers,
Paul

[John Steel]

I'm just glad I'm not working at SpaceX trying to design something to get us to Mars!

Good to hear from you Greg - If only E. Musk would dedicate his attention to something really useful . . . like sound insulation!

[Waka]

Just an update to my previous post, in reality it would probably look more like this...

Screenshot 2020-06-06 at 16.02.02.png

I'm thinking BAD panels to front the angled reflective parts of the sawtooth side walls would be a nice option.

The walls could either be concealed behind fabric so the sawtooth is hidden and appear to be just "normal" walls, or just left exposed which might look quite cool.

Here is a link about CID rooms, prototyped by the BBC for anyone interested in a similar concept http://downloads.bbc.co.uk/rd/pubs/reports/1995-04.pdf

Paul

Hi Paul, sorry I've been away for so long! I like the look of the saw tooth design. I was considering something similar for my design. I noticed that there was potential for the first reflection on an angled "tooth" to reflect against the face of the adjacent tooth, and then across the width of the room right through the mix position. I would think this could possible be avoided though by making the "non-angled" face of the tooth absorptive instead of reflective though.

Have you ray traced for this possibility?

Try a ray that hits a tooth close to the adjacent tooth, then reflects against the flat section of that tooth and trace the secondary reflection back into the room.

Dan

[Paulus87]

Just an update to my previous post, in reality it would probably look more like this...

Screenshot 2020-06-06 at 16.02.02.png

I'm thinking BAD panels to front the angled reflective parts of the sawtooth side walls would be a nice option.

The walls could either be concealed behind fabric so the sawtooth is hidden and appear to be just "normal" walls, or just left exposed which might look quite cool.

Here is a link about CID rooms, prototyped by the BBC for anyone interested in a similar concept http://downloads.bbc.co.uk/rd/pubs/reports/1995-04.pdf

Paul

Hi Paul, sorry I've been away for so long! I like the look of the saw tooth design. I was considering something similar for my design. I noticed that there was potential for the first reflection on an angled "tooth" to reflect against the face of the adjacent tooth, and then across the width of the room right through the mix position. I would think this could possible be avoided though by making the "non-angled" face of the tooth absorptive instead of reflective though.

Have you ray traced for this possibility?

Try a ray that hits a tooth close to the adjacent tooth, then reflects against the flat section of that tooth and trace the secondary reflection back into the room.

Dan

Hey Dan, good to hear back from you again, how's everything where you are?

Yes, the intention is for the inside of the teeth to be absorptive, essentially it would almost be like hangers that are only absorptive on one side. Sort of...

Here's a diagram to demonstrate. The reflections from the teeth would either reflect energy to the rear of the room where it can be absorbed or diffused, as well as ricocheting other reflections within the absorption between the teeth.

I was thinking instead of using solid reflective panels I could use either slats or BAD panels, which would scatter the reflections a little more as well as still providing some extra absorption.

The aim is to have a very large ray free area with 3 listening positions, but at the same time providing a nice working environment with self noise cues. So any diffusive or reflective elements would not provide any direct feedback from the loud speakers and yet the room is not overly dead.

What do you think?

Paul

[Waka]

Hey Dan, good to hear back from you again, how's everything where you are?

It's OK here. Been crazy busy with work (I build software for dental practices) as we've been speed releasing new features to allow practices to avoid waiting rooms. We created a Web portal for patients to sign documents at home and completely redesigned the medical history form designer and tablet app to work in browsers on phones etc.
But I've started doing the odd thing on the studio as I get some time.

The design looks good to me. I wonder whether there will be any lobing issues with the wave guides/reflectors being equally sized though

You also use up all your wall space for other treatment types. But you could have them centered at listening height along the walls with space below and above, so then you have the upper and lower corners for specific frequency treatments, or horizontal super chunks.

I'm actually planning on implementing a simpler version of this in my inside out ceiling along the center of the room. I plan to have no dropped ceiling cloud at all.
Each celling module will have a 25mm mdf board in it, angled to deflect sound waves to the rear wall.
They will all be behind my fabric ceiling and hidden, which will be great. I can't put the absorptive sections for them to act as waveguides in mine though, due to the non angled bits being my ceiling joists!
I've ray traced it and the joists/noggins shouldn't cause much of an issue though.

I'm doing this along the middle "third" of the room, as this is the least effective location for absorption anyway and the angles are easily enough to kill any floor>ceiling flutter echo.

Dan

[Paulus87]

Hey Dan, good to hear back from you again, how's everything where you are?

It's OK here. Been crazy busy with work (I build software for dental practices) as we've been speed releasing new features to allow practices to avoid waiting rooms. We created a Web portal for patients to sign documents at home and completely redesigned the medical history form designer and tablet app to work in browsers on phones etc.
But I've started doing the odd thing on the studio as I get some time.

The design looks good to me. I wonder whether there will be any lobing issues with the wave guides/reflectors being equally sized though

You also use up all your wall space for other treatment types. But you could have them centered at listening height along the walls with space below and above, so then you have the upper and lower corners for specific frequency treatments, or horizontal super chunks.

I'm actually planning on implementing a simpler version of this in my inside out ceiling along the center of the room. I plan to have no dropped ceiling cloud at all.
Each celling module will have a 25mm mdf board in it, angled to deflect sound waves to the rear wall.
They will all be behind my fabric ceiling and hidden, which will be great. I can't put the absorptive sections for them to act as waveguides in mine though, due to the non angled bits being my ceiling joists!
I've ray traced it and the joists/noggins shouldn't cause much of an issue though.

I'm doing this along the middle "third" of the room, as this is the least effective location for absorption anyway and the angles are easily enough to kill any floor>ceiling flutter echo.

Dan

Dental software, I never knew such a thing even existed! Maybe the dentists I go to are very old fashioned since they still seem to be using pen and paper That's cool though, I definitely do not enjoy the dental waiting rooms.

Dan, do you mean UNEQUALLY sized? Because they're all different sizes, they gradually get narrower towards the rear of the room and the angle also gets narrower. I have thought about lobing issues, but it's so complex since each panel is at a different distance and angle to the speakers that I wouldn't even pretend to know how to predict that. My thoughts are that if the reflective parts are not fully reflective but simply slats for example then the angled panels are actually just funny shaped absorption with some slats to bring back some life.

I did also think about angling only the central part of each side wall, which I may still do but I kind of like the idea of any potential reflections coming from that low down being deflected as well as absorbed. The upper parts already have horizontal super chunks

Yes, your ceiling plan should work very well, in fact that is basically what I have done by using hangers across the central part of the ceiling, the angle of each individual hanger is different, gradually rising front to back. I look forward to seeing how yours turns out.

Paul

[Waka]

Dan, do you mean UNEQUALLY sized? Because they're all different sizes, they gradually get narrower towards the rear of the room and the angle also gets narrower.

Ha! I missed that! Yes I can see them getting narrower now

I have thought about lobing issues, but it's so complex since each panel is at a different distance and angle to the speakers that I wouldn't even pretend to know how to predict that.

Yes it's seems a massive job to predict, I can't imagine it causing issues with all the absorption in the "wells". To me it the whole wall will act more to just divert energy towards the rear of the room and reduce it's energy quite significantly in the process.

Have you managed to find any of the cons to the design that stopped it entering the mainstream in the 70s and beyond?

Dan

[Paulus87]

Dan, do you mean UNEQUALLY sized? Because they're all different sizes, they gradually get narrower towards the rear of the room and the angle also gets narrower.

Ha! I missed that! Yes I can see them getting narrower now

I have thought about lobing issues, but it's so complex since each panel is at a different distance and angle to the speakers that I wouldn't even pretend to know how to predict that.

Yes it's seems a massive job to predict, I can't imagine it causing issues with all the absorption in the "wells". To me it the whole wall will act more to just divert energy towards the rear of the room and reduce it's energy quite significantly in the process.

Have you managed to find any of the cons to the design that stopped it entering the mainstream in the 70s and beyond?

Dan

to be honest there's not a lot of info out there on this design...

I do not think it was ever in the mainstream as far as I can tell. Wolfgang Jensen was the pioneer of this design but I can only find one studio still in existence today that he helped design, which is called H.O.M.E. in Hamburg.

The only other mention of this design which also refers to Wolfgang is found in Newell's book. It doesn't mention any potential flaws with it either.

This design (or very similar) is used frequently nowadays for cinema mix/preview rooms, I see a lot of them with sawtooth sidewalls. I am assuming it's because it reduces first order reflections across multiple listening positions. The main difference being that the angled panels are all the same size and angle and distance from the boundary.

John Brandt uses angled slatted traps, often only one but in large rooms such as mine he will use up to 3 or more. I've interviewed him and asked him about them and he said it is to make the room sound a little larger than it is, as well as add some life back in to his heavily damped rooms.

The way I see it, it's a way to fit a lot of deep treatment with large surface area on to the side walls without taking up loads of space that one large angle would. It maximises the length and width of the reflection free zone to the point where almost the entire room is first reflection free. It also means slats or reflective elements can be added without the risk of causing flutter due to the two side walls no longer being parallel. I'm not finding a lot of arguments against it at this point, but I may put it up for scrutiny on a coupe of other forums as well, and report back!

Paul

BTW - regarding your ceiling. To get some absorption as well as deflection up there you could always make the panels perforated and have fibre behind or make each one a membrane trap targeting different frequencies.

[Waka]

This design (or very similar) is used frequently nowadays for cinema mix/preview rooms, I see a lot of them with sawtooth sidewalls. I am assuming it's because it reduces first order reflections across multiple listening positions. The main difference being that the angled panels are all the same size and angle and distance from the boundary.

John Brandt uses angled slatted traps, often only one but in large rooms such as mine he will use up to 3 or more. I've interviewed him and asked him about them and he said it is to make the room sound a little larger than it is, as well as add some life back in to his heavily damped rooms.

The way I see it, it's a way to fit a lot of deep treatment with large surface area on to the side walls without taking up loads of space that one large angle would. It maximises the length and width of the reflection free zone to the point where almost the entire room is first reflection free. It also means slats or reflective elements can be added without the risk of causing flutter due to the two side walls no longer being parallel. I'm not finding a lot of arguments against it at this point, but I may put it up for scrutiny on a coupe of other forums as well, and report back!

That's interesting info. I came to the same design myself (saw tooth) whilst designing my RFZ, it seemed as if they would work fine. Your design is an improvement on that, by having the absorption in the "wells", so they act as waveguides and don't have the troublesome return reflections.

BTW - regarding your ceiling. To get some absorption as well as deflection up there you could always make the panels perforated and have fibre behind or make each one a membrane trap targeting different frequencies.

I'm considering something along these lines. I'm looking at maintaining as much energy as possible though, so I might leave them solid. I have the option to drill holes afterwards if needed. But they're not very useful locations for helmholtz/membrane traps anyway being in the center of the room. I could treat certain modes slightly if needed, but probably not the most efficient treatment location.

Dan