Zaphs B3S's with aperiodic membrane?

[GuyPanico]

In an attempt to make the B3S's even smaller, could one use an aperiodic membrane? Then decrease the cabinet volume maybe 2/3 or 3/4. I would of course have to play with the baffle step. But my ears are not tuned terribly well, so I dont need perfection. Any thoughts would be appreciated.

[planet10]

Surely worth a try... we are just embarking on a similar project with the CSS FR125S -- we'll see how they work stuffed into a 4 litre enclosure.

dave

[owdi]

AFAIK, in order for an AP to be effective it needs to vent into a volume separate from the driver, because it's out of phase. If you want really small why not try dipole?

Dan

[planet10]

Originally posted by owdi
AFAIK, in order for an AP to be effective it needs to vent into a volume separate from the driver, because it's out of phase.

That's news to me. Most aperiodic boxes vent to the outside. the Dynaco A25 being the most famous.

dave

[noodle_snacks]

Originally posted by owdi
AFAIK, in order for an AP to be effective it needs to vent into a volume separate from the driver, because it's out of phase. If you want really small why not try dipole?

Dan

I'd also question the logic in going dipole with this driver, i think the excursion limits, by the time you'd equalised everything would severely limit output.

I thought aperiodic vents basically acted as an acoustic resistor between the inside and outside of the box, simulating the effects of a larger box (air inside the box becomes more compliant), at the cost of a higher f3 and a steeper 18db/oct roll off.

[planet10]

Originally posted by noodle_snacks
[I thought aperiodic vents basically acted as an acoustic resistor between the inside and outside of the box, simulating the effects of a larger box (air inside the box becomes more compliant), at the cost of a higher f3 and a steeper 18db/oct roll off.

pretty much....

http://homepage.mac.com/tlinespeaker...nAperiodic.pdf

dave

[sreten]

Hi,

The Vas of of the B3S is 0.8L, the box volume 3.2L.

Box volume is not part of the design, its actually lazy re-use
of existing boxes which the article should make more clear.

Aperiodic loading is pointless as as stated they should be used
with an active crossover, sealed box loading down to 1L is fine.
Baffle step changes should not be an issue, with same baffle width.

For full range use the Aurasound driver is the 3" bass champion.

/sreten.

[planet10]

Originally posted by sreten
For full range use the Aurasound driver is the 3" bass champion.

I can't disagree with you there sreten

Pretty good eleswhere as well -- and if you want to guild the lily, it plays well with the Apexjr $1 tweeter.

dave

[soongsc]

Originally posted by planet10


pretty much....

http://homepage.mac.com/tlinespeaker...nAperiodic.pdf

dave

I think the Jordan Watts were designed with this in mind, however, once they were enclosed in very small boxes, the aperiodic design lost it's function.

[Jim McPherson]

Originally posted by sreten
Hi,

The Vas of of the B3S is 0.8L, the box volume 3.2L.

I've seen you quote this many times sreten. Were did you get this info?
According to:
Parts Express
And:
Solen
The VAS of the B3S is 1.6L or 0.06 cu. Ft. The box volume of 3.2L is double VAS, this doesn't seem "lazy" to me. It seems like a reasonable box size. Sure it could be smaller, but 1L is surely too small.

-Jim