Stryke AV15 PR (1 Viewer)

[ArthurJ]

After reading the forum, I have decided I am going to do Strykes recommended AV15MKII 24" Cube PR design. It comes out to $415 before shipping and tax. How will this fair with other popular pre-manufactured subs? I will be putting 500watts to the driver. Also, for the price of the PR’s I could do two AV15MKII sealed and have money left over for a 1000watt amp, would this be a better route? Thanks!

 

[ArthurJ]

Just figured out the costs in Canadian...

AV15MKII Dual PR18-1600 T/S + 500 watt plate amp = $930

Dual AV15MKII Sealed + 1000 watt plate amp = $950

Help?

 

[Dan Hine]

Hmmmm...personally I think I would go with the dual sealed AV15's. With two of them, 1000watts and an LT you should get just as good response (almost at least) as the bass reflex design with (warning, audiophile word coming up, warning!) "tighter" bass because of the lower group delay. Much lower in fact, though some would argue that the frequencies where GD would be a problem would be low enough that you wouldn't notice. Not to mention that the sealed box could be smaller...more for less basically.

I'll be honest though and say I've not yet built a sealed design so my suggestion is based purely on theory and from other user's opinions. My next sub project will probably be sealed though.

 

[ArthurJ]

Excuse my ignorance but what's an LT?

 

[Brett DiMichele]

Linkwitz Transform: http://www.linkwitzlab.com/filters.htm#9



"A majority of drivers exhibit second order highpass behavior because they consist of mechanical mass-compliance-damping systems. They are described by a pair of zeroes at the s-plane origin and a pair of complex poles with a location defined by Fs and Qt. The circuit above allows to place a pair of complex zeroes (Fz, Qz) on top of the pole pair to exactly compensate their effect. A new pair of poles (Fp, Qp) can then be placed at a lower or a higher frequency to obtain a different, more desirable frequency response.
This allows to extend the response of a closed box woofer to lower frequencies, in the above circuit example from 55 Hz to 19 Hz, provided the driver has adequate volume displacement capability and power handling. The equalizer frequency response is shown below, correcting for a woofer with peaked response (Qp = 1.21) and early roll-off (Fp = 55 Hz), to obtain a response that is 6 dB down at 19 Hz and with Q = 0.5 . "

 

[Owen Bartley]

I've been thinking a lot about doing a sealed design for my next sub as well, and I'd be very interested in seeing how a sealed dual-AV15 turns out. Have you considered a sealed Tumult? (just thinking out loud)

 

[Brett DiMichele]

My sealed AV12 (Criticaly Damped) could use an LT.....

I mean.. Don't get me wrong it has output.. But I did make
the enclosure really small I didn't take into effect
just how much space that Sunfire amp takes up inside the
enclosure.. An LT would get me more output down low I have
plenty of output in the high 20's and 30's and it just
gets more ridiculous the higher up you go

 

[Frank Carter]

Is there a reason you haven't considered dual vented AV15's?

 

[Brett DiMichele]

I would do dual sealed AV15's but that's just me.. I am not
fond of Bass Reflex at all

 

[Allen Ross]

how hard was it to build an LT to your specific box. I am sure there are different types of op amps which one would be better musically? and what about distributers?

 

[JimRHIT]

I have 2 PR15s that I would be willing to sell you rather cheap. I have the original boxes for them as well ... [email protected]

 

[ArthurJ]

How much is an LT? And where can I get one? I think I will do the dual sealed for now...I can always add four PR's in the future. The reason I am not doing a traditional ported design is because of room. Brett, how large is your enclosure?

 

[ArthurJ]

also, what is a good size enclosure? Should I go 2.5 per driver? Thanks!

 

[ArthurJ]

I have thought about a tumult...dunno what would be the pro's/con's compared to the dual AV15???

 

[ArthurJ]

Ok, I could do a single sealed tumult with 1000watt amp BUT I would have to wait a good 5-6 months before I could add PR's. Anybody think this is a better route then dual AV15's? Cost wise the Tumult will be about $100 more!


Is it true the tumults need major tweaking and they have a hard time blending in with mains? Thanks!

 

[Dan Hine]

Is it true the tumults need major tweaking and they have a hard time blending in with mains? Thanks!

Not one bit. The people I know that have one have not had any problems. In fact, IIRC Brian Bunge has had an easier time with his Tumult than anything else...could be wrong.

Where did you hear that?


Dan Hine

 

[RichardHOS]

ArthurJ,

Do a google search for Rod Elliot and go to his projects website. Somewhere in there you will find the Linkwitz-Transform project, where he describes in detail the circuit, how it operates, and how you build one. He also has printed circuit boards available for sale for next to nothing (like $10 to $15 or so). All you need to do is download the spreadsheet that calculates the component values for you, order the various components, and follow Rod's instructions for assembling the board.

 

[ArthurJ]

In layman terms, what exactly does an LT do? Thanks a lot for those who have helped. Any more opinions on the Tumult vs. 2 AV15's are appreciated!

 

[MattD]

In layman terms, what exactly does an LT do?

LT

 

[GrahamT]

You can get the Tumult in Canada but not the AV15 so you may have to pay a brokerage fee.
As for the LT, it allows you to manipulate or "transform" the Fc and Qtc of a given box and driver.