The Dahlquist DQ-10 Page
I’ve decided with this page to depart somewhat from the kit and scratch-built theme because I keep inheriting
fun vintage equipment, in this case a pair of legendary Dahlquist DQ-10s. It's no accident that they closely
resemble the revolutionary Quad electrostatics. The idea was to approximate as closely as possible the openess,
depth and accuracy of the Quads with the reliability and economy of dynamic drivers.Except for some black applique that has peeled loose from one of the stand’s legs, and a few places where
the grill cloth has come away, they’re in good shape. Mechanically, the woofer’s foam surrounds have also
rotted away. I decided to of course refoam the woofers, and simply bypass the existing yellow poly caps with
.01mfd film and foil poly caps. Although the chokes aren’t up to the current (sorry) standard, the integrated system
performance is based on the total resistances, so I decided to leave well enough alone. The high-current capability
of my Phase Linear 400 amp (my Adcom as well) overcomes the low efficiency reputation of these speakers
anyway, and I’m not on a campaign to deafen myself or blow drivers.
I was too impatient to wait for the refoam kit and caps to arrive, so I installed a pair of 70s vintage long throw
12” paper woofers, that I had refoamed from another pair of vintage speakers and measured well in that enclosure.
The Dahlquist woofers are Advent 9” cones in a 12” basket, with the surround mounted to a fibreboard spacer
ring. The 12” woofers dropped right in. I fired them up, aware that the balance wouldn’t be the same.
I then realized what all of the hubub had been about. It’s hard to believe that those 5 drivers could be so well
integrated, sans the software we’re so dependent on, designed with only a slide rule and oscilloscope. Granted,
it helps to be Saul Marantz or Jon Dahlquist. To some the weak point is the piezo super tweeter, I was skeptical
too, but that’s purely theoretical. The extended treble is smooth as can be. Just stunning transparency, imaging and
transient response. Although I had nothing to compare it to, the midbass seemed clean and unbloated despite the
different parameters and output of the 12” woofer.
The parts arrived and I soldered in the caps. The refoam was easy as I’d done it before. Out came the 12” woofers
and in went the Advents. I also attached sound dampening pad to the surfaces of the stands where the speakers
rest to decouple any interaction there. I made a woofer break-in cd with 2 cuts from the RCA cd The Classic Film
Scores of Bernard Herrmann: The Octopus, from Beneath the 12 Mile Reef, and Lonni Bound by Ropes, from White
Witch Doctor, and played it on repeat for a morning. The entire Herrmann cd is in fact demonstration quality.
Interestingly, I've read a number of comments about the Dahlquists lacking bass and needing a subwoofer. I listen in a
1560 cu.ft. living room that opens into a 1040 cu.ft kitchen, and I have no problem reproducing realistic orchestral, jazz
and even pop bass at reasonable levels, that gets my attention even if I'm at the sink, on the other side of the house
from the speakers. I'm talking about clean, extended, realistic, not inflated or boom-box bass. My amp was an Adcom
5400, now a Phase Linear 400, with a 25 ft run of 12 gauge oxygen-free copper wire.
Until I decide to revive my retired transmission lines or hear that new project siren song, these will be my main speakers.
I’m including links to pages that have the caps, refoam kit and sound dampening that I used. Some refoam kits claim
to be the original specs, but I’m completely satisfied with the performance after the one I used. You can also ship your
Dahlquists to have expensive upgrades, or order replacement drivers and upgrade kits, but for under $40 I can’t imagine
better results. If you decide to go my route, or whatever experience you’ve had, let me know. I’m having a blast, and
I hope you are too. Click on the pictures if you decide to order the repair/upgrade parts.
If this site meets your needs and has been informative and helpful, please realize that I can only keep it going for both
of our benefits if you continue to make your purchases by clicking through from here to my affiliate partner. Thanks so
much for your patronage.
Look here to see reviews of the DQ-10 by actual owners.Look here to read about open baffle design by Siegfried Linkwitz.
Go here to mirror-image the Dahlquist DQ-10.
