how to include the subwoofer?


I have power amps (Kharma MP150s) that only have balanced inputs.

I have a preamp (Nagra PL-L) that only has selectable outputs (balanced or single ended), and only one set of balanced outputs. It does have a pair of unblanced.

I have speakers (Wilson Benesch Curve) that go down to about 35 Hz.

I have a subwoofer (Velodyne DD12) that I would like to use to round out the bottom octave and help with some room nodes.

What is the best compromise:

> to use the pair of unbalanced outputs on the preamp and use RCA-->XLR adapters at the amp end, and regular RCA cables to the subwoofer;

> to use XLR y-cables out of the preamp balanced outputs

> use an electronic crossover that has both balanced inputs and both balanced and unbalanced inputs (expensive solution, but offers added capability of not running the speakers full range).

None of these seem very good to me. Any other thoughts? As always your insights are most apprecited
dgaylin
Dgaylin,

If you're looking to maintain the "purity" of the main signal path,
what are your choices?

I can pretty much assure you that the high pass in the NHT is less audible
(and much more flexible) than the high pass in the SMS-1 as I have
extensively A-B'd the two. The Velo ain't terrible, but I knew it was there.
Also, the added flexibility of the NHT allowed for a better crossover function,
as I can high pass at my chosen turnover frequency and steeper slope than
the SMS allows. So, what can you do?

1) Use the active x-over of your choice (you might be more comfortable re:
transparency in the main path with Bryston or Marchand, but there's the $
issue) or

2) Run the Curves full range, bypassing the DD's high pass and try to
"snug up" the DD from below, using only it's internal high cut
filter. You might get a good x-over function, but you've blown the
opportunity to maximize the benefit of the DRC.

My point is: Cable adaptors won't improve "purity" in the main
path (DD's high cut ain't great) unless you forgo DRC (low x-over point). If
your question is: "Is DRC worth some slight (in my case, inaudible to me)
degradation of the main signal path?", my answer would be "Without
Question, Yes, Yes, Yes"

OTOH, YMMV.

Marty
Dgaylin,

Sorry I missed your intervening post re: the smooth bass response you're already getting from the Curves. My room makes such a result impossible. So, as Emily Litella once so aptly put it "Oh...never mind".

Marty
Hey Marty, no apologies necessary -- I appreciated your additional post. But actually, running the Curves full range and using the Velodyne it is still possible to get some benefit from the DRC in the Velodyne. By setting the low pass in the Velodyne to around 100, it actually reinforces the Curve's bass response below this level (and of course handles the low bass where the Curves drop out). As a result the main system is playing at lower volume to prduce a desired loudness. With the sub producing some part of the loudness, it is possible to tune the bass response of the room using the DRC in the sub. True, I'm not affecting what the Curves are doing at all, but according to the SMS software the response is considerably flatter than just running the Curves full range without the sub. Maybe someone will tell me this is sonically impossible, but I don't think so -- and unless the measurement microphone software (and my ears) are lying, it works.

I may try the external crossover still. But may wait to find a Bryston 10b. Or I may go ahead and try the X2. Still think about it.
Good point. It never occurred to me to try this. That's probably because, IME with measuring system response in room, I've found that almost any speaker with extended bass response will produce significant excess energy somewhere above 80 hz - in most rooms. Taming this can't be done with DRC in your proposed set-up. You could use bassbusters or maybe you don't need to if your room/speaker system is different than any I've measured - which seems to be the case here.

Marty
BTW,

I'm pretty sure that the NHT X-2 is available direct (oand IIRC from AudioAdvisor.com for a few bucks less) with a money back guarantee for a home trial period. There's little at risk if you're tempted to check it out.

Marty