How about the sealed box with "variovent"?

[planet10]

Originally posted by sonicfury
Something with a small chamber , size something like 1/2 or 1/3 VAS and the small chamber being ... connected to the secondary chamber (which is much bigger) via a variovent.

That describes the Dynaco A35/A40

dave

[sonicfury]

Yeah northcreek ... i remember - right.
It was this guy from northcreek

Thank you !!!

[Pete Mazz]

Found it!

Multichamber Aperiodic Progressive Damping

Pete

[7V]

Originally posted by Pete Mazz
Found it!

Multichamber Aperiodic Progressive Damping

Looks interesting, Pete. Is that the animal that you were describing some time back, kelticwizard?

Steve

[kelticwizard]

7V:

Yes, that is the one.

That paper certainly clears up the confusion I had, as well I am sure that many others had, about whether an aperiodic design had one chamber or two.

Much thanks, SonicFury and Mazz.

[7V]

I seem to remember that some time ago Speaker Builder ran a series of designs where the driver was mounted in a box which was ported into a larger rear enclosure where the size wasn't too critical - cupboard, car boot (trunk), etc.

Maybe this concept could be tuned with a variovent type of arrangement (or a sock in the tube - I've still got some spare socks that I haven't yet filled with sand).

Steve

[gaston_pdu]

Hi everione, i have read all posts and exchanges mails with some speakers gurus like troels gravesen, and the variovent appears t be the only solution for some "decent bass". the driver parameters are these:

Z: 8 Ohms
Re : 5,5 Ohms
Fr: 46 Hz
Qa: 4,2
Qe: 0,7
Qt: 0,6
Mms: 0,034371 Kg
Cms: 3,48E-04 New/m
Bl: 8,84 Wb/m
Sd: 0,035968 m2
Vas: 6,31E-02 m3
Rms: 2,37 Kg/s

the simulation programs like WinISD and BassBoxPro 6 says an ideal enclosure about 100 L or more. a 45-50 liter cb is mandatory.

Someone can help with the folowing?

How many variovents?
size of each?
how much material inside each one?
material compressed or loose?
placing in enclosure?

thanks, gaston

[GM]

For my records, what brand/model driver is this and are these published or measured specs? Pe, Le, Xmax?

Don't know what the Variovent's DF is, but doing a sim in MJK's PORTED WS to determine a DIY golden ratio 1.75ft^3 (gross) cab variant:

L = 23.4"
W/D = 8.93" x 14.16"
driver down 10.82"
stuffing density = 0.2lbs/ft^3, or ~5.6oz of polyfil
vent = 2" dia x 4" long stuffed with ~5.6oz of polyfil (contain on each side with a mesh screen)
vent down 22"

No real bass output to speak of though with an aneochoic ~60Hz F3, this cab is just too small.

GM

[gaston_pdu]

The driver is an Audifiel 10bx, made in Argentina. I'm studying there. Is the best affordable driver I can get. The audio world here is so so prehistoric, that drivers like scan-speak, vifa, morel and so on does not exist!. the bestyou can get are car drivers from pioneer, some alpine and they are really expensive for a student, so the 10bx is the only choice. See it at www.audifiel.com

The specs are not published, since the driver does not have then on it's box. So i wrote to the manufacturers and they sent them las week. The other parameters says "1" in the exel file they sent, that's why i did not post them. So Troels suggested the variovents as the only solution to get nice bass from the 10bx, and that's why i'm here.

Thanks again, i will try a 42 L cab with a home made variovent on the back, tuned by ear. Some suggestions and advices will be WELL received.

gaston

[Variac]

The 8HX looks pretty cool as a full range. Is it expensive?