Recommendation for Subwoofer for Dahlquist DQ-10s

I am currently restoring a pair of Groomes G101A tube monoblocks, to be paired up with my Cary SLP98P preamp - which will ultimately drive a pair of Dahlquist DQ-10's. I am in the market for a good subwoofer to run with the Dahlquists. I have a two part question:

1) Is it best to go with a passive or an amplified subwoofer with a preamp/vintage monoblock amp set-up?

2) If I decide to go with a passive subwoofer (with a built in crossover), or if I go with an amplified subwoofer (with a built in amp and crossover) -- where do my monoblock amps come into play in the wiring setup?

The crossover has to be in the equation at some point in order the filter the lower frequencies from the Dahlquists, but I want to keep all tubes in my formula.

I can't answer Q1, but for Q2, did you want to drive the sub using high level or low level inputs? High level depends a lot on the sub you get I think. If you use low level you simply connect the sub to the preamp outs on your Cary.

Have you considered using the Dahlquist sub and xover? With that vintage setup, I would be very tempted to go that way.
I have thought about going that route, but there are some other subs out there that simply blow the Dahlquist sub away. Not to mention, I believe I would need an additional amp to power that thing.

Can I run: Preamp, to an active sub-woofer (with amplifier and crossover - filtering and playing only the lower frequencies and amplifying them), to my monoblocks amplifying only the higher frequencies for my Dahlquists?


Is it better to run: Preamp, to my monoblocks amps, to a passive sub-woofer (with a crossover - filtering and playing only the lower frequencies) then ultimately to my Dahlquists (playing only the higherer frequencies)?
IMO you're better off with an active sub. I think many active subs have high pass out, so you run pre out to the sub inputs, then run from the sub high pass out to your monoblocks.

I run a REL subwoofer which takes a slightly different approach to integration - you run your speakers full range, and set the subwoofer x-over point to come in below your speakers. You can also run the REL using high level inputs (ie tapped to your amplifier speaker outs), or low level from your pre-outs.

You will want to read the manual of any subwoofer you're considering buying to see how it connects and what they recommend.
yOU'LL LAUGH! I use a Yamaha YST-160 active sub, in the corner, set at 40Hz. Leave the DQ-10's to roll off by themselves. That little Yamaha, which uses a pair of 8" woofers blends seamlessly with the Dahlquists while providing for a much more palpable low end. It is MUCH better then the old Dahlquist subwoofer, especially if you used their passive crossover box which destroyed the sound of the 10's.
These Yamaha subs are small, and cheap, and you can stick one in each corner of your room and never know they are there until you play some music. Or, you could invest in some other more expensive sub, but keep the crossover LOW, and 24 db per octave.
I'm not laughing, Planerguy.... your method is exactly as I did it, although I used an Audio-Pro B2-50 at the time. People can get the wrong ideas about the function of a subwoofer. In classical recorded music as the prime example, you don't really want to hear it, so much as feel it. 40 Hz is about right, but you can play with the crossover frequency on the active sub to meet your ears' approval. I did the same with the Quad ESL63s with similar positive results. I still use the Audio Pro similarly with my current rig.
If you want to stay vintage or maintain retro look. the Dahlquist DW-1 actually will work and sounds quite good but you need to drive it with a beefy amp. If you can find a good condition Dahlquist DQ LP-1 active/passive crossover, that will allow you to experiment and split the signal as desired. Be sure to use high quality (to replace the originals) caps on the highpass out section of the DQ DLP-1