Review: Dahlquist DQ-10 Speaker


Category: Speakers

Hello fellow audiophiles, I want to share with you my listening experiences of Jon Dahlquist's complete speaker system.

Many times you read reviews of the DQ-10 speakers and they most always comment on the lack of low-end and power hunger of the speakers. While true, this does not provide a true representation of what the complete Dahlquist speaker system is capable of. For those familiar with the Fulton Mod-J system, it would be like critiquing this system without its base module.

The complete Dahlquist speaker system consist of the famous DQ-10 main speakers; the DQ-1W subwoofer, the DQ-LP1 electronic crossover (and DQ-ST10 speaker stands for proper main speaker positioning).

The DQ-10 is a 5-way, open baffle, time-aligned speaker; the DQ-1W is a passive 13" subwoofer; and the DQ-LP1 is an electronic crossover that features a passive, distortion free high-pass section and a freq/gain adjustable low-pass section.

Several years after initial introduction, Dahlquist modified the main speaker design to mirror image the left and right speakers. This provided symmetry and widened the soundstage even further. If you are looking to buy a set, this is the version to get!

After 30 years of ownership the Dahlquists system still takes my breath away. The sound stage is extremely wide, I can close my eyes and picture the musicians playing, with each instrument precisely located across the front of my listening room. The accuracy and clarity is stunning, piano notes are clear and true; symbols ring with purity; acoustic guitar strings sound crisply plucked; and drum beats are powerful and tight.

The 5-way crossover network is the reason for the speaker's power hunger, it has several power resistors in it that really heat up. But what you get in return for this design is accuracy (purity of note) and clarity (distortion free) of sound because each speaker driver only has to work in a limited frequency range. This is especially true of the DQ-10 woofer driver which only has to work down to 60hz with the electronic crossover in the setup.

Because of its power hunger, it is extremely important to drive the Dahlquist system with ample power. I drive the main speakers with a Bryston 4B and the subwoofer with a Bryston 3B in mono mode, a total of 800 watts. What is important for any amplifier to achieve powerful and tight base is to not be current limited. This is the case, as with the Brystons, when the amplifier doubles its output power output when the speaker impedance is halved (i.e. 200 watts @ 8 ohms, 400 watts @ 4 ohms). Plus, the amplifiers must have a high dampening factor (i.e 500+) to ensure that the speaker driver has a single, fast excursion for a drum beat, without ringing.

With this setup, there is no one who would say the Dahlquist system lacks low-end. The frequency range is very wide, something like 25hz - 30khz. The adjustability of the DQ-LP1 crossover allows for completely seemless integration of the subwoofer into the mains. You cannot tell that the low base notes come from a seperate speaker box from the mains!

Given today's market prices, you can acquire a nice set of DQ-10s for $500, a DQ-1W for $200, and a DQ-LP1 for $300 = $1000 for the complete system. I venture to say that you cannot buy another full range speaker system for this price that will beat the Dahlquist system. You would have to spend multiples of that price to try to come close.

I certainly recommend them!

Associated gear
Click to view my Virtual System
jjh92
When they started producing a mirror imaged version they also upgraded the caps in the crossover with metalized poly's. What they didn't do and I have done is change the 80mfd cap that separates the woofer from the rest to a Solens poly. This is the most important cap of all since all the midrange and up pass through this cap. If you have the version I have and it still has the electrolytic cap in this spot, pop for the Solens. You will truly be amazed.

I also have an older pair (not mirror imaged) that need the woofers refoamed. I don't know whether to fix them or sell them.
I had a pair for around 3 years...many years ago...I agree, very good speakers. I enjoyed many hours with mine...I suspect I still would, if I had not sold them!

Dave
The DQ 10 is what got me into higher end audio 30 years ago. It was the most amazing sound i have ever heard, at the time $900 seems like a million dollars to me and i never did get the dalquist. Years later when i got a real job, i got a pair of acoustat 3 and then the martin logan and now avantgarde which are far more costly then that pair of dalquist.But when i think of high end, DQ 10 still pop into my mind, Kinda like that first love that makes you smile. Great speaker indeed.

Muzcal 10-20-07
I also have an older pair (not mirror imaged) that need the woofers refoamed. I don't know whether to fix them or sell them.
Fix 'em! It's only about $23 for the kit for a pair of woofers. It's not very hard to do; mostly it takes some patience and care.

Here's a page on it at Parts Express, which also sells the kits: http://www.partsexpress.com/Tech/260-915.html

With smaller cones, you don't really need to remove the dustcap and shim the voice coil. I replaced the foam on a pair of EPI A70s with 6-1/2" woofers and didn't need to shim them at all.

For the DQ-10, you would probably use the same kit as for the original, Large Advent speaker: http://www.partsexpress.com/pe/showdetl.cfm?DID=7&PartNumber=260-955, but I'd call Parts Express to make sure.

The reason I think this would work is that although the Dahlquist and Advent woofers weren't quite identical, they are very similar. Both used a 9-1/2" diaphram in a 12" basket with masonite insert, and they both contracted to the same driver mfr. The two brands' mfg. lots could get mixed up if they weren't specifically labeled. I got this info directly from Saul Marantz when he was demonstrating the DQ-10s at the stereo store I worked at in SoCal in 1975.

http://www.partsexpress.com/Tech/260-915.html
I have been using DQ10s since 1977 when I purchased the audio store owner's speakers that I frequented when I was a Grad Student at Rutgers. I have used them ever since and have been using them in my home theater. I finally totally rebuilt them in 2001 following the design from Layne Audio in Tennesse. The speakers were redesigned without the Super Tweeter. The speakers again were mirrored and the drivers were replaced with a Dynaudio Tweeter, Dynaudio upper Midrange, a Peerless dipole lower Midrange and a Proprietary woofer. Additionally the crossovers were redesigned and the speakers were set up for biwiring with 2 sets of terminals.

The crossovers were split between the top and bottom of the cabinet and the upper 3 drivers were mounted on a single board.

The speaker performance has improved dramatically from their original form. The sound is much like the original DQ10s but on steroids. The speakers are faster with better imaging, soundstage, more percussive, and more musical. I use a Nola LCR Reference as the Home Theater Center Channel. When I can afford it and hopefully sometime later next year, I will replace the subwoofer in my system with the Nola T-Bolt III.

Rich