Dahlquist DQ10

[Fitnessed]

Some research i have gathered on the DQ10,prior to buying a set and discovering more information,please note that this post may be updated as i find out more.....

Jon DAHLQUIST-Was an aerospace engineer and was obsessed with designing the perfect speaker. Also had previously worked for the Bendix corporation and NASA, specifically on the Lunar Landing Module.

The original company was in Jon Dahlquist's garage in and they latter moved to a larger space. The address of the company was 27 Hanse Ave, Freeport, NY 11520 and latter 601 Old Willets Path,around 3 employees in the beginning and up to 15 in the later years..

Saul MARANTZ-1911-1997 Was a American musician-inventor-Engineer..
Founded MARANTZ in 1948....

Saul owned a major share in Dahlquist and apparently heard the dq10 prototype prior to investing.

Carl Marchisotto- Joined Dahlquist in 1976 and worked their for 15 years.
Was involved in modifications and and went on to found Alon speakers as well as his current company NOLA,much respected high end speakers..

Around 27,000 pairs of DQ10s were made.1973-1989

Early ones had a chicago telephone company C.T.S woofer serial numbers upto 2000 afterwards it was a Advent masonite 10inch, woofer which had a 12 inch spider frame.

Later models 39,000 onwards had the serial numbers on the speaker terminal backplate.
Earlier serial numbers are a small white label positioned in the driver cabinet (my pictures to follow will show the location)
Crossovers had mylar caps at about 22000 and mirror imaging became standard at about 27500.
Dahlqlist early on sent out information on how to mirror image dq10s post production.

Audio review has 110 reviews on and comments on these speakers at 4.8 out of 5..


1972-The Dahlquist speaker corporation was founded in Hauppauge,New York

1972-Dahlquist d10 was exhibited in the New York Audio Show.

1973-Dahlquist d10-Was in production-

1989-Jon Dahlquist-Was severely injured in a car crash and was in a coma for 12 days,Dahlquist was sold 1st May 1990...

After taking a punt on some poor advertising pictures,and a couple of hours drive.
I was pleasantly surprised to find a really tidy pair that had been owned for over 30 years.
Owner had bought els57 and a quad 33 and 303 and returned them and paid £1200 for the dq10s from a hifi shop in Leeds..
Whilst these have been cherished,the previous owner had swapped in a pair of replacment woofers as the foams have disintegrated on the original advent woofers.Luckily the new woofers are dimesionally the same and no holes or additional cutting have been generated , so easily reversed.
Luckily the original woofers have been kept and i metered out the voice coils and all is good,so will look at re-foaming them asap.
I checked all the drivers in the top section and they are all factory and the supertweeters are fine also and checked level using sound meter.

IMG_4708 by Vintage Audio, on Flickr
These are mirrored and the boards have been sprayed black so u dont see the brown wood through the grills.

IMG_4738 - Copy by Vintage Audio, on Flickr
IMG_4735 by Vintage Audio, on Flickr
IMG_4729 - Copy by Vintage Audio, on Flickr
both backs are in the same condition..
url=https://flic.kr/p/2oZJDxz]

[/url]IMG_4681 by Vintage Audio, on Flickr
crossover networks may need new capacitors,onwards with a re foam first,as they already sound nice with the wrong bass drivers in surprisingly good and in a smaller room,will live downstairs in a bigger room with els57, the ns1000 and jr 149 work really well nearfeid,these are going to need some space me thinks...
tIMG_4732 by Vintage Audio, on Flickr
the blingy speaker terminals will get standardised when i put the origional woofers back inIMG_4719 by Vintage Audio, on Flickr
serial numbers are matching,the tweeter fuse is 1 amp but should be 0.8, a lot of people bypass this so perhaps a slightly thicker one is more optimum..

IMG_4724 by Vintage Audio, on Flickr
IMG_4726 by Vintage Audio, on Flickr


IMG_4741 - Copy by Vintage Audio, on Flickr
Side cheeks are all in really nice condition,will lightly sand and add some danish oil,the stands are metal and well made,bit like my els57s perhaps they need to be a bit higher but perhaps at the expense of bass...

Absolutely delighted with these little gems already and will need to re-foam and then look at recapping,they do sound really nice already are around 10 cm shorter in width than els57 and a fair bit heavier and wider in the back..
Have run them up on a quad 306 but think they will need more watts/damping factor to control the bass so may swap in a tag 100x5r or potentially get a quad 405/2 etc...

 

[sailor]

I haven't seen a pair of those for many years, brilliant speakers. I've helped a friend replace the top two HF units with an Audax tweeter (I think, was a while ago) which cleaned up the highs very nicely.
The piezo horn tweeter is, I'm afraid, rather nasty. I took my GAS Son of Ampzilla around for him to hear and compare to his Kenwood integrated that could not drive them well. It did make a splendid improvement. He had a Kenwood marble base turntable which I thought was pretty good but can't say the same for the amp.

There is much you can do with the crossover. You may not like to hear this but I would keep the coils and discard the rest. Not everything in audio has improved over time but capacitors certainly have. The sand cast resistors are noisy and could/should be replaced too.

They are IMO definitely worth the effort. Properly refurbed would take a lot to beat

 

[Tony L]

The piezo horn tweeter is, I'm afraid, rather nasty.

It looks like the same unit that one saw in any number of budget PA systems, bass amps etc from the late-70s. It was never a high-end device, though I guess it is crossed-in here so high up it barely matters.

PS I’ve liked DQ10s when I’ve heard them, so it can’t be doing too much wrong!

 

[Zombie]

If the piezo thingy is the super tweeter, why not just disconnect it and let the other tweeters take over? Great speaker, though.

 

[Tony L]

I’d personally just restore to as close to as-new condition as possible. It is a classic speaker, it didn’t get that reputation by accident. Modification is very unpredictable and will certainly devalue them.

 

[Blue Belle]

Would love to hear a pair of those, but always thought that they looked like the speaker that Jack built.

 

[Yank]

At the time it was claimed that the Dahlquist woofer wasn't quite exactly the same as the Advent, just that both companies bought their parts from the same supplier. But that could have just been obfuscation.

The idea behind putting a 10" cone in a 12" frame, necessitating the Masonite spacer, was apparently because available 10" frames weren't deep enough to allow as much excursion as the designer wanted.

The mid cone was a Philips unit, the mid and HF domes were from MB, and the supertweeter of course was the Motorola piezo horn.

Oh, and here's the crossover schematic:

 

[Yank]

Here's a forgotten piece of Dahlquist history - the brochure for the DQ6, which was never put into production:

I scanned this from an original that I own.

The industry rumors about the DQ6 were (1) the prototype sounded better than the DQ10 and thus it was suppressed, or (2) the prototypes were stolen after a trade show demonstration, and Jon Dahlquist was never able to duplicate them because he had failed to document the crossover modifications.

 

[Fitnessed]

I’d personally just restore to as close to as-new condition as possible. It is a classic speaker, it didn’t get that reputation by accident. Modification is very unpredictable and will certainly devalue them.

Exactly my plan Tony.
Going to do the foam surrounds and get the original woofers in first...
Potentially going to recap the crossovers,and a rub of oil and thats it as they are in super condition..

 

[Yank]

the blingy speaker terminals will get standardised when i put the origional woofers back inIMG_4719 by Vintage Audio, on Flickr
serial numbers are matching,the tweeter fuse is 1 amp but should be 0.8, a lot of people bypass this so perhaps a slightly thicker one is more optimum..

I think the original binding posts were Pomona 5-ways.

 

[Fitnessed]

It looks like the same unit that one saw in any number of budget PA systems, bass amps etc from the late-70s. It was never a high-end device, though I guess it is crossed-in here so high up it barely matters.

PS I’ve liked DQ10s when I’ve heard them, so it can’t be doing too much wrong!

I haven't seen a pair of those for many years, brilliant speakers. I've helped a friend replace the top two HF units with an Audax tweeter (I think, was a while ago) which cleaned up the highs very nicely.
The piezo horn tweeter is, I'm afraid, rather nasty. I took my GAS Son of Ampzilla around for him to hear and compare to his Kenwood integrated that could not drive them well. It did make a splendid improvement. He had a Kenwood marble base turntable which I thought was pretty good but can't say the same for the amp.

There is much you can do with the crossover. You may not like to hear this but I would keep the coils and discard the rest. Not everything in audio has improved over time but capacitors certainly have. The sand cast resistors are noisy and could/should be replaced too.

They are IMO definitely worth the effort. Properly refurbed would take a lot to beat

Thanks for the feedback and information. Like u say a big amp is needed...
Have been reading up about recapping,its a bit of a mindfeild for me.
As there are also so many HifI boutique caps and it is where i draw the line with keeping it original.
Do not want to do fancy fandagle caps on the original board, also believe the film ones are a lot larger and expensive.
So will stick to slightly better oem plus type caps (solen polypropylene) perhaps...
Perhaps like my ns1000ms i may build an external crossover and keep the original set up for reversibility.
Did not think they would sound this good with the wrong woofers in.....:0

 

[Fitnessed]

I think the original binding posts were Pomona 5-ways.

Awesome

 

[Fitnessed]

s-l500 by Vintage Audio, on Flickr
s-l1600 (1) by Vintage Audio, on Flickr

s-l1600 by Vintage Audio, on Flickr

 

[nws56]

DQ 10's figured prominently in the mag adverts of influential dealers in the mid 70's. Jeffries Hi Fi used to promote the Linn / Grace / Supex / 32 / 250 / DQ 10's as the ultimate musical system . ' Challenges fully accepted ' it used to read. I did indeed read those adverts a lot , and it's funny how those things stay in the mind. I do hope that those vile adverts from banks and car makers don't have the same longevity..... Jeffries would borrow the ideas from Jon D when he launched his Nightingale speaker. They were less than half the price of the DQ 10's, I ended up buying a pair. Whilst working at Laskys a colleague splashed out on the real thing and even had them running on dem in the shop. The Yamaha CR 1000 receiver seemed plenty powerful enough. Even in the shop environment I could hear the smooth, effortless quality that my Nightingales were not giving me.
Fast forward 15 years and I was asked to dispose of a pair of DQ 10's for a friend of a friend, and naturally had to try them in my system first. It was a dream coming true before my eyes , but the reality was that I preferred the Ruark Talisman's I had been using for a couple of years. So I sold them . And have regretted it every time when I look back, because I did not realize at the time that the large and complex crossover may well have been suffering the effects of out of spec components.
As may yours. There was a guy who restored his non functioning crossovers with modern components who posted the whole procedure on Art of Sound forum. Or maybe DIY audio. Worth a look before you dive in.
Have fun !

 

[Fitnessed]

Would love to hear a pair of those, but always thought that they looked like the speaker that Jack built. [/QUOTE

Funny how we judge a book by its cover...

i can see why and thought the same..

.

I had doubts about my ns 1000s before purchase and thought they looked a bit cheap.....

on both accounts i was massively proven wrong in quality and sound...

 

[Fitnessed]

DQ 10's figured prominently in the mag adverts of influential dealers in the mid 70's. Jeffries Hi Fi used to promote the Linn / Grace / Supex / 32 / 250 / DQ 10's as the ultimate musical system . ' Challenges fully accepted ' it used to read. I did indeed read those adverts a lot , and it's funny how those things stay in the mind. I do hope that those vile adverts from banks and car makers don't have the same longevity..... Jeffries would borrow the ideas from Jon D when he launched his Nightingale speaker. They were less than half the price of the DQ 10's, I ended up buying a pair. Whilst working at Laskys a colleague splashed out on the real thing and even had them running on dem in the shop. The Yamaha CR 1000 receiver seemed plenty powerful enough. Even in the shop environment I could hear the smooth, effortless quality that my Nightingales were not giving me.
Fast forward 15 years and I was asked to dispose of a pair of DQ 10's for a friend of a friend, and naturally had to try them in my system first. It was a dream coming true before my eyes , but the reality was that I preferred the Ruark Talisman's I had been using for a couple of years. So I sold them . And have regretted it every time when I look back, because I did not realize at the time that the large and complex crossover may well have been suffering the effects of out of spec components.
As may yours. There was a guy who restored his non functioning crossovers with modern components who posted the whole procedure on Art of Sound forum. Or maybe DIY audio. Worth a look before you dive in.
Have fun !

Great story thanks for sharing

The main things with the DQ10s are the foam woofer surrounds...

The 80uf capacitor is also prone to degradation apparently and at a minimum that is a recommended swap out.

its is a fantastically quirky speaker array with fuses on the tweeters,before i bought mine i pulled the grills off and cofirmed the working status of each driver...

 

[Fitnessed]

DSCF7189 by Vintage Audio, on Flickr

DSCF7173 by Vintage Audio, on Flickr

Can only imagine this would sound immense...

 

[TimF]

I always liked the DQ-10's, really, most of Dahlquist speakers were very good. One of my friends bought a new pair in early 1980's, and still has and uses them as his main speaker to this day.

I know that some do just unwire the piezo super-tweeters and leave the rest stock save for refoaming/recapping. There certainly is quite a lot of information out there on the web for the DQ-10's.

Enjoy them!

 

[nws56]

Great story thanks for sharing

The main things with the DQ10s are the foam woofer surrounds...

The 80uf capacitor is also prone to degradation apparently and at a minimum that is a recommended swap out.

its is a fantastically quirky speaker array with fuses on the tweeters,before i bought mine i pulled the grills off and cofirmed the working status of each driver...

Yes, I never thought to look at the foam surrounds ... may well explain the disappointment. Just as well they didn't stay - we had 4 young children bouncing around and hard up to the wall was the only safe place to have speakers.
My Lasky colleague was forced to have his in his bedroom...they only stayed with him for a couple of years. Excessive bouncing around in that small arena may or may not have been the problem. If you are reading this Erik - please do tell...

 

[Fitnessed]

okay some progress managed to refoam x1 woofer.

The Yahoo Dalquist group a truly excellent resource on these speakers,plenty of files and information.
There where 10 revisions to the dq 10s mainly crossovers.

All the crossover diagrams and factory information has been scanned and placed on the Yahoo Dalquist group.

My Dq10S were built in 1976,and have been post- factory mirror imaged,this was offered as a kit and also became a factory mod from new in 1977.

Mine have the 50v red and black temple caps which are electroltytic. Carl Marchisotto improved the crossovers in 1976 and further revisions.
Pleased that i have the latest crossover with his mods.

So.....
Suppose i should get my peak esr meter out and also test the resistors values or just go for a blind recap....decisions...

All will be factory value if i move forward on this.

My caps are electolytic, the later yellow ones are polyester.
And have been uprated to 100v apart from the 50v 80uf, which were available as a upgrade kit from Dahlquiest.

If i changed to polyester caps and retain factory spec, i am assuming this is the cheapest option and relevant to what they used,ideally don t want to go fancy fandangle at all....