Rivera Silent Sister Style Iso Cab Design

[Dave Peterson]

Thinking of building a speaker isolation cabinet. The Rivera Silent Sister (SS) seems clearly the best design for a smallish solution. (I'll probably make mine a bit bigger.) Just wondering if I have his basic plan right? Can anyone who has one tell me? (See drawing.)
As Paul Rivera says in his promo video on the SS (https://youtu.be/ESOrSKGojtg), the cabinet is not completely sealed (which is the problem with all the other designs). In the SS, the sound pressure ports down a labyrinth. I know there's a port at the front of the speaker, and I think there's also one at the back, but not sure. Can anyone verify this? Since I think I prefer the sound of an open back cabinet, would there be any problem porting the back of the speaker like this?
Also, I plan to tilt the speaker mount board, as pictured, to help prevent the standing waves that could result from parallel surfaces. I suppose it would be optimum to angle some other surfaces, but that's too much hassle for me. I'll probably also put rockwool or similar insulation throughout the cabinet.
Paul says they added 32 feet to the cabinet via the labyrinth port. By putting in 7 staggered "shelves," as in my drawing, it adds only about 8' of labyrinth. So, in order to get 32', you'd need way more shelves spaced much closer together. (Math gives me a headache but, the SS is 31" x 20" x 16", so....)
Am I on the right track? Any helpful comments? Thx.

 

[Ben Lawrence]

I have never seen this. At a first glance I was thinking it was kinda ridiculous until I came to the part where the actual cabinet puts out little noise. So it is for recording or very quiet stage sound? I know its not un-common for people to throw the guitar amp away from the stage and mic it. So this seems kinda cool. Wish I could help you further on the build details but Im guessing someone on here has some insight. Good luck. Is there a set of plans you can follow. I would do that and not deviate to start using the recommended drivers. Someone put some time into this and likely tried a bunch of variations so I would build off of plans provided.

 

[Dave Peterson]

I didn't include the microphones in the drawing but, yes, this cabinet is used for running a guitar amp speaker at full volume (so both the preamp and main stage tubes can start to sing). It's used on (or behind) stage so the stage volume is reasonable, or (as I'll use it) for home recording, where you can't crank a guitar amp to full volume.
On another forum someone noted a similarity to a "transmission line" cabinet design. I googled that and, though I see what they're talking about, the purpose of this long port is different.
Do you know if there is someone on this board who would know...
- how one might attempt to create a 32 foot long labyrinth in a box this size; i.e., how narrow of a passageway can you get away with?
- would it be OK to port the back side of the speaker into the labyrinth at a random point, or do phase issues come into play?
The Rivera cabinet can be run using a variety of 12" speakers. They can even provide it without a speaker so you can mount your speaker of choice (Celestion, Eminence, etc.)