passive radiator tumult for music applications

[tech.knockout]

If properly designed, can passive radiator designs using the Adire tumult woofer be used for music applications?

is the group delay a concern?

[Bill F.]

Sure, a PR Tumult alignment could work great. If you tuned it low enough, the group delay could all be tucked away behind 20Hz. However, you'll probably need 2 18" high-excursion PRs to keep up, and the low-tuned box won't be small.

If you don't already use WinISD Pro, download it, punch in the Tumult specs, and see what you come up with. Great tool.

[RAW]

As a fact I am just building a few more 24" cubes for a person who is using twin 18" Stryke PR'S along with the MULT.
3 times lucky
They all hit very veyr well and tuned with mass added to the stock PR as well.


Al

[tech.knockout]

has anyone here compared a PR tumult to rival offerings from SVS/HSU when it comes to music?


I know a guy from Hometheaterspot who reported his PR tumult didnt fare so well in music , but was great for HT.

[Bill F.]

If I were doing a Tumult sub, I'd make it about 7cu. ft. (probably a 24" external cube when you add driver displacement and extensive bracing) tuned to 14 Hz with twin Stryke 18" PRs.

At 1Kw, the Tumult would be excursion limited at 12 Hz (making 107 dB anechoic), and the PRs would still have some room to breathe. Yikes!

Group delay would be less than 7 ms at 30 Hz. Since IMO group delay is the enemy of music, this would likely be a very musical alignment in addition to hitting extremely deep.

Hey Raw, did I just clone your sub? What's your tuning? And BTW, what are the PR specs? I'm going by memory--can't find them on the web...

[RAW]

Bill
The Styke PR'S
PR18-1600 T/S
Fs: 4 Hz
Qms: 85
Vas: 1840 L
Mms: 1600 g
Sd: 1200 sq cm
Vd: 9 L
Xmax: 3" p-p

Retail $125
Were weighted to 2250g of mass
Tuned to 19HZ in the 24" cube using 1.25" MDF

Johns site is getting revamped and you will soon seem my name as the Canadian dealer for Stryke.

Alhttp://www.stryke.com/passiveradiators.html

[Bill F.]

Thanks for the PR specs, Al.

Have you ever tried 3/4" walls with thorough bracing? Might net you less weight and more internal volume... Just my

(OT) By the way, I've got a PR design I've been working on with 5" p-p excursion. Only PR I know of that could go one-on-one with a Tumult. I'm going to be putting my prototype through its paces with an Aura 1808. I know it sounds nuts, but stay tuned...

[thylantyr]

I know a guy from Hometheaterspot who reported his PR tumult didnt fare so well in music , but was great for HT.

PR, ported, sealed, all have their sonic signature. It's best
you audition a PR system to see if you like the sound.

My preference would be a ported box if music is a priority over HT.
Besides, don't you think a Tumult ported will fare well in HT ? /heh

[Bill F.]

I agree they each have their sonic signatures, but I feel the signature of a PR is generally less intrusive than that of a port.

Also, for a given subwoofer tuning/alignment, a PR will always give you a smaller box than a ported system. The advantage will be especially great at low tunings optimized for high SPL where ported boxes have to maximize port cross section to avoid port turbulence noise. In addition to being bulky, the resulting port length also brings harmonic resonance issues into the picture.

A well-designed PR alignment takes up no extra space and exhibits less self-noise and no higher harmonic resonances. IMHO, the only real downside is the cost of the PR.

[Spearmint]

I realise that this thread is about PR's and the Tumult, although I haven't heard any PR subs I do have a ported Tumult tuned to 15Hz, and it performs just as well for music & HT.

Although most of my listening is music it is not 2ch, these days I much more prefer multichannel DVD-A's and DVD's.

If you are determined to get a Tumult I think you would be happy with it in either PR, ported, or sealed, it is a great driver and can deliver the goods.