Series-Tuned Bass Reflex Questions - technical

[soongsc]

Re: Double-length ports in same box

I think this would play a major role.

Deep & loud bass is beautiful only when it's under control.

In comparison, vented enclosure is already boomier then closed, not to mention open baffle or horn. (Of course I mean good designs/well built for all of them)

Band pass mulitple vented enclosure is indeed worse then simple bass reflex box.

Among all of the enclosure types I've listened to, in the case of vented design, it's good only when mated with big, expensive, professional underhung driver.

I kind of agree with this. Whenever you create a resonance, you alter the current-voltage phase at the resonat point such that the current does not control the driver, but allows the driver to resonate on it's own. This is not good from a fidelity point of view.

Hi guys

This is a slightly different idea. How would you go about modelling a box with two ports of different length in the same volume (i.e. not a dual chamber box- see picture below)? This would be to extend the lower bass of a driver with a very low Q. Any ideas? Can one use UniBox (as per RJ's suggestion)?

Thanks,
Deon

If you look at it from a mass-spring point of view, you can get a general idea what the problem would be.

 

[sandyhooker]

double tuned enclosures revisited..

Claudio Negro's website deals with this type enclosure and includes formulas and test results. I've built (over the years) a number of the Augsberger/Weems design and have been largely satisfied . The original article was published in 1961
and the box used an LE-8 JBL (recollection??). My first used an ElectroVoice SP-8B and was considered a marvel by listeners. Eight inch speakers were not the norm then.

I built others over the years and used Peerless and MCM drivers. I'm about to build another using an MCM woofer . This to boost bass in my system.