Jennings Research speakers 70s - info needed

cortico

Active Member
Hello all,

Just got these speakers, the peerless type tweeter grabbed my attention and the built quality is great, real walnut veneer and swivel pedestal.

I never heard about it before. I learned they were built in CA, besides that there isn't much information available online.

Soundsv like a fun restoration project, I would appreciate any information you may have.

Thanks,
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Congratulations, Cortico! I am familiar with the Jennings Research name, but as near as I can remember I've never heard or seen any of their speakers. Those look quite well-made. Can you provide a close-up photo of the tag next to the tweeter? If there is a tag on the input terminals, we need to see that, too.

If you intend to open them up, be sure to take detailed pics of the drivers and any numbers or labels on them, and a pic of the crossover network.

Why? Because the "numbers guys" here will be able to help you with detailed research, and in the future there will be other owners of these looking for information, as well. Your info will add to the library.

By the way, how do they sound?

GeeDeeEmm

Edit: Looks like you have the Contrara Pedestal Mk I. There's a smattering of information on line.

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Had a pair of Vector One's back in the day powered by a 'sui 7070, loved them. I'd love to find a pair of those today. The Vector One is a passive radiator loaded system. GDM's brochure shows the Vector 1A, a later 3-way design.

I have a pair of the smaller, single woofer "Rectangle Speaker", a very respectable 8 inch 2-way.
 
Hi guys thanks for your help. I just finished nourishing the cabinets, it came out really nice.

I toke the chance to check the woofer number, they are all the same below are the printed numbers on the basket:

120-08108
8HU2714
91 7639

I haven't pull out the tweters but they spear to be the original peerless.
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The crossover makes me scratch my head, it only has 3 inductors and a single cap!? I would appreciate any help understanding this!

I can't tell the capacitance value, the print wasn't visible, it would be a good idea to replaced the with new ones.
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My understanding is that Jennings was a big JBL salesman who decided to make his own speakers. I remember when they came out they sounded good, and looked very good. And the rotating on the base thing seemed very important for a while when everyone was hepped up on dispersion and a direct line from tweeter to ear (this was during the transition from cones to domes) before the role of indirect sound was much noted. But I bought a pair of Frieds once I had the money.
 
I wish I could get more info on the crossover, apparently is a pretty simple circuit 3 inductors and a 8uf capacitor, probably a high pass filter.

I have order capacitors, since one is a electrolytic and having 2 different ones makes my OCD kick in :)

Here is the full setup after minor cabinet reconditioning.
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Handsome. But you could use the rotating base to point the speakers at the listening position.
 
That looks stunning, Cortico! What a great match between the Jennings and the component cabinet. Quite pretty, sir. How do the Jennings sound as is? You should do a video and post the system in action on the new thread that Glen started. I'd love to hear them.

You may have already noted it, but what are the other components in the pictured assemblage?

GeeDeeEmm
 
Tanks for the kind words.

The system is pretty simple, I have the speakers being driven by a Marantz 2270 I recaped a few year ago, Pioneer PL530 turntable, Parasound CD changer and a Parasound 1000 DAC. All cables are DIY, built with Canare wires.

There is nothing fancy, although it sounds great to my ears. Maybe, slightly colored by the Marantz, it imprints something in the overall sound, but I think that is a good thing :)

The speakers sound good too, I am still adjusting too it, my term of comparison are the Polk CRS SDA. The First impression was that there was a bit of lowdness in the midrange, but I kind of fixed that rearranging the polyfill inside, as example I placed as shown on the sketch (A) below. Apparently, the scheme increased the bass and the overall sound seems more coherent now. Jazz and acoustic instruments have a very pleasent realism...
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A video sounds a good idea, I'll record and post.
 
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Congratulations, Cortico! I am familiar with the Jennings Research name, but as near as I can remember I've never heard or seen any of their speakers. Those look quite well-made. Can you provide a close-up photo of the tag next to the tweeter?...

Forgot to post the label, here is a picIMG_7623.JPG
 
I had a chance to recap the speaker today. Finaly was able to read the existing caps properly, the film was 8uf but the electrolytic was 4.7uf. I suspect the last one was replaced at some point, judging by the way it was soldered in.

Anyway, I have replaced both with a 8uf, the speaker where the 4.7 was seems to have a tinny bit more highs, could be just my brain but this is fixable with just a click on the Marantz independent left and right treeble control...
Any thoughts?
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Found this info, but no technical specs yet.

"Jennings Research was based in Los Angeles, California, USA and founded in March, 1975 by Tom Jennings. Mr Jennings had been the head of marketing for JBL in the late 60’s, early 70’s and was instrumental in the success of the JBL Aquarius series. In a different time he was also CEO of Wald Sound.

As it is with most driven entrepreneurs, Jennings stuck out on his own, brought in a dedicated group of talented associates and made some amazing speakers. The initial product line at Jennings Research was called the “Contrara Group”. At the top of the line was the "Contrara Elan Pedestal" with twin Audax tweeters and Audax woofers. Next up was the "Contrara Group Pedestal", which features twin woofers and a single tweeter.

Also included in the model series were the "Contrara Group MKii Rectangles" which had single woofers and tweeters in each cabinet. Other than the high quality drivers and crossover networks, the most striking thing is their physical appearance: all the Contrara Group pedestal systems feature hand-rubbed, solid dark walnut cabinets with mosaic tops. The Rectangles have the same high quality finish but without the mosaic tops. The pedestal models also have very heavy cabinets mounted on swivel bases which is quite unique, to say the least.

There were a few other speaker models, not as well known but still carrying the Jennings Research badges. They were introduced in the summer of 1975 and the company initially made quite a splash with an advertising campaign in national magazines such as "Popular Science" and the "New Yorker Magazine".

The well-designed systems sold well, but, unfortunately, the very high cost of materials and labor, let alone the cost of marketing and sales, put Jennings Research in a precarious position compared to the well-funded competition. There was no question the product is excellent but, as happened to so many companies in the crowded high fidelity market, they just couldn't stay afloat. Occasionally, Jennings Research speakers turn up for sale but are considered very rare because, generally speaking, they sound VERY good and most audiophiles tend to consider these "keepers".

The company also introduced a line of amplifiers the next year, but they appear to have only been in production for only a couple of years."
 
Really nice speakers. That black cap really had to go. Beautiful woodwork. The 4.7 mfd cap could put the crossover freq around 2.4Khz. The 8mfd would change that point.
 
Glad I changed the capacitors, right and left channels are balanced and smoother now, caps seem a good choice too, I may redo the internal wiring at some point down the road.

I have to say, that the solid wood intrigues me. is common sense that solid wood is not desirable in speaker cosntructuction due to resonance, wood movement, etc... Unless, if it's used intentionally, I learned some manufacturers have done this, obviously the case here.

Important to mention that not all cabinet panels are solid wood. When looked from the inside, The interior sides, drivers baffle, and bottom panels look like a compact wood agglomerate. it could be interior agglomerate lining panels, difficult to tell.

In my non-audiophile opinion, these speakers are easy to listen and sound pretty good along with the rest of my rig. Charlie Byrd & Stan Getz, "Jazz Samba" sounded incredibly real. Focused, smooth highs, natural sounding midrange and bass. I think the cabinet construction imprints a mellow acoustic character that gives a realistic sound and punch to these particular instruments.
 
Cortico, I recently picked up a pair of these. Beautiful speakers! I also have mismatched caps in mine. What were the specs on the new Sonicaps you installed?
 
I've just been assigned a pair of these in my role as the electronics guy for our local Hospice Thrift Store. Cabinets are lovely. On the listening test not a sound out of the tweeters, but they work fine on my signal generator. One of the capacitors has disintegrated, so I'm going to assume both are dead and will replace them. Both the lower woofers look like the photo earlier in this thread. One of the upper woofers has some of the same designation - is it a replacement or what was used in that location? Photo attached. The other one is a Chinese driver that needs replacing. Does anyone know a source for these drivers?IMG_20190113_202235.jpg
 
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