John Sayers' Recording Studio Design Forum Archive

Hi there,

I'm working on a new vocal coaching/writing/composing room in the studio (http://www.johnlsayers.com/phpBB2/viewt ... 25#p133225) and was wondering how to make the best acoustic use of a couch riser?

Unless this room truly benefits from it, I'd like to avoid a tuned resonator and was wondering if fitting hangers in a semi-open "box" would be a good option?

If yes, why not also create an open riser for the production desk with hangers beneath it?

Has anyone already tried either?

Just thinking...

was wondering if fitting hangers in a semi-open "box" would be a good option?

Hangers need to be pretty long: then need to "hang". Under a riser floor, you'd only have a few cm, so I don't think that would be useful for hangers.

I recently did a riser floor at the back of a fairly large studio, and it worked out fine. Unfortunately, I'm not at liberty to go into details publicly about that, since it was a paid job for one of my customers. But basically, you vary the sizes of the joist bay cavities, and keep the coupled using the concept of "space coupling", but all at different frequencies. You can tune the floor to actually help with bass trapping, if you do it right. Here's the RT-60 graph for that room:
And here's how it was originally:
Obviously, there's a hell of a lot more treatment in that room than just the floor, but the floor plays a fairly decent part in keeping the low end under control.

So yes, a "riser floor as treatment" can be done, but it takes careful design.

If yes, why not also create an open riser for the production desk with hangers beneath it?

I would not do that: it would place your listening position too high in the room, probably.



- Stuart -

Hey Stuart,

Thanks a lot - wow, those graphs look impressive!

One of the rooms we have in the studio was designed by a quite renowned local acoustician and he has used the floor as a basstrap, which was surprising to me as you seem to say that a good hard concrete floor is the most desirable option. Maybe he used that acoustic coupling principle.

Now, in the specific example you talked about, are we looking at the whole floor or just a riser aka a box to put the couch on?
I would imagine some sort of 50 (H) x 120 (depth) x 230 (w) cm MDF box.

One of the rooms we have in the studio was designed by a quite renowned local acoustician and he has used the floor as a basstrap, which was surprising to me as you seem to say that a good hard concrete floor is the most desirable option. Maybe he used that acoustic coupling principle.

He probably did. That makes sense. Personally I wouldn't do the entire floor like that, since you'd have nothing to couple it to acoustically, but you can do the rear section, if needed.

Concrete certainly is the best surface you could ask for in a studio, but many studios also do want a riser at the back for a client couch or other seating area, so in those cases you do need to compromise.

Now, in the specific example you talked about, are we looking at the whole floor or just a riser aka a box to put the couch on? I would imagine some sort of 50 (H) x 120 (depth) x 230 (w) cm MDF box.

In this case, the riser is about 6.5m wide, 3.8m long, and about 18cm high. It's just a riser at the back of the room, starting more than a meter behind the engineer's head. So the engineer is still sitting over a nice solid floor (laminate over concrete). And it's not just MDF: the floor is actually a sandwich of several things: you have to put lots of mass on it, and you also need to keep it damped as much as possible. The floor "sandwich" in this case is a bit more than 6cm thick.

- Stuart -

OK thanks.
This whole concept of acoustic coupling sounds kind of alien to me. Not sure I want to try my hand at such a delicate task!