Jennings Research speakers

2

Comments

  • SlapahoSlapaho Posts: 183
    Wood looks fantastic!
  • If I'm seeing this right, it couldn't be simpler.
    One high pass cap for the tweeter.
    Two inductors for the woofers.

    I'd get rid of the hong kong cap asap. :)
    Others can recommend one for you.

    @ 6 ohms 75w max you won't need a lot of power with these I'm guessing.
    Just good power.
    cortico wrote: »
    Can anyone explain the crossover designer?

    Studio 2 equipment;
    Yamaha a-s2100 Amp, CD-2100 CD player, T-S500 tuner
    Loudspeakers: Harbeth p3esr, Polk RT7
    Cables: Aural Harmony Sonnet Interconnect II, WireWorld Equinox 7 speaker,
    Black Cat silverstar 75 ohm digital, Signal Digital Power Cord, PS Audio Perfect Wave AC-3,
    Pangea SE14, Voltz supplied interconnects
    Optional: Arcam DV88 DVD/CD (HDCD) player, Polk SDS-400 speakers
  • corticocortico Posts: 316
    edited September 17
    Interesting, the other speaker has different cap. Apparently a bipolar electroliyltic, not sure about the capacitance, can't read the values.
    o2co6g3mlqo3.jpg

  • corticocortico Posts: 316
    edited September 17
    The cap is 8uf, I'll get 2 sonicaps and replace them. I only have one grill, today I templated the frame on acad all I will have 2 new ones Lazer cut on mdf

    5h1qxn5u9yng.jpg
  • corticocortico Posts: 316
    edited September 18
    Planing to use a CNC machine to cut the new baffles, it's Petry enjoyable to watch it working. This one is cutting door frames and routing for recessed pulls for one of the millwork pieces of an apartment I am renovating...

    m923mjx9lgq6.jpg
  • corticocortico Posts: 316
    edited September 18
    Here is the nude existing screen frame, 469hpufum36r.jpg
    o6j3i8m6ggre.jpg
  • Viking64Viking64 Posts: 496
    :'(
    Polk SDA SRS 2.3TL
    Silk Audio MS38SE Tube Amp
    Yamaha DSP A-1 AV Amp
    Panasonic TC-P65S2 Plasma TV
  • corticocortico Posts: 316
    edited September 19
    By the way, I was experienent with different polyfill placements and noticed drastic changes:
    6lwbekji5w76.jpg

    Scheme A had better bass response which makes the sound more coherent, the mids seemed more balanced...
    Post edited by cortico on
  • Funny you should try this as I was thinking what if...
    what if you redesigned this as a three way speaker.
    Leave the bottom woof full out and make the upper
    a mid woof. I couldn't find any specs so I kept my
    mouth shut. :|
    Studio 2 equipment;
    Yamaha a-s2100 Amp, CD-2100 CD player, T-S500 tuner
    Loudspeakers: Harbeth p3esr, Polk RT7
    Cables: Aural Harmony Sonnet Interconnect II, WireWorld Equinox 7 speaker,
    Black Cat silverstar 75 ohm digital, Signal Digital Power Cord, PS Audio Perfect Wave AC-3,
    Pangea SE14, Voltz supplied interconnects
    Optional: Arcam DV88 DVD/CD (HDCD) player, Polk SDS-400 speakers
  • corticocortico Posts: 316
    edited September 19
    Yeah, I am all about experimenting.

    Although, these speakers sound really well in my humble system. I am sure the Marantz imprints it's own thing...

    but hey! I play electric guitar, I love coloration, why shouldn't I?! Haha B)

    Anyway, this was a great find. I have to new 8uf caps coming in. Two different capacitors on left and right crossovers makes my OCDness kick in... can't deal with that. Argh!
  • A fun project for sure.
    Studio 2 equipment;
    Yamaha a-s2100 Amp, CD-2100 CD player, T-S500 tuner
    Loudspeakers: Harbeth p3esr, Polk RT7
    Cables: Aural Harmony Sonnet Interconnect II, WireWorld Equinox 7 speaker,
    Black Cat silverstar 75 ohm digital, Signal Digital Power Cord, PS Audio Perfect Wave AC-3,
    Pangea SE14, Voltz supplied interconnects
    Optional: Arcam DV88 DVD/CD (HDCD) player, Polk SDS-400 speakers
  • corticocortico Posts: 316
    edited September 20
    Here is a sloppy vid closer to the speaker

  • Yep2Yep2 Posts: 778
    edited September 20
    Its almost like you need it in your hands!
    I think I could do some "Bidness for the better" if I had em in my hand, on my bench! :)
  • corticocortico Posts: 316
    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 on this?

    msqmbvrlu4kr.jpg
    z7ise0wgdr9g.jpg



  • [Deleted User][Deleted User] Posts: 91
    edited September 25
    Yes, one (or both) of these is/are wrong.
    You need the original specs. :|
    Studio 2 equipment;
    Yamaha a-s2100 Amp, CD-2100 CD player, T-S500 tuner
    Loudspeakers: Harbeth p3esr, Polk RT7
    Cables: Aural Harmony Sonnet Interconnect II, WireWorld Equinox 7 speaker,
    Black Cat silverstar 75 ohm digital, Signal Digital Power Cord, PS Audio Perfect Wave AC-3,
    Pangea SE14, Voltz supplied interconnects
    Optional: Arcam DV88 DVD/CD (HDCD) player, Polk SDS-400 speakers
  • corticocortico Posts: 316
    edited September 25
    Yes, one (or both) of these is/are wrong.
    You need the original specs. :|

    Yeah, I have scavenged the interwebs and can't find any schematics.

    I am sure the black is the original, the aluminum cap was soldered to the leads of the previous capacitors.

    Let's see as the new caps "acclimate" :), I like the sound...

    Today, I am dropping off the grille frame to the millworker shop, he will generously scan it and replicate. This is a must-have, my 2-year-old likes to scratch speaker cones.
  • xschopxschop Posts: 635
    Stick with the 8uF. It crosses lower. That and it was probably the original type they used, looking at other images.
  • corticocortico Posts: 316
    edited September 25
    xschop wrote: »
    Stick with the 8uF. It crosses lower. That and it was probably the original type they used, looking at other images.
    Yes, this makes sense, the new ones are 8uf.
    x7lqvtcbkxvl.jpg
  • corticocortico Posts: 316
    I was able to source this info:
    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.
  • corticocortico Posts: 316
    edited September 29
    I am glad I changed the capacitors, right and left channels are balanced and smoother now, caps seem a good choice too. The original binding posts are solid and the cabinet is completely airtight. 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 incredible detailed and real through these speakers.

    Very focused, super smooth highs and natural sounding midrange and bass. The tweeters are fantastic and the four 8" drivers displace decent amounts of air and slam too :) when Listening Radiohead "The Bends" at a moderate-high volume level. The cabinet construction imprints a mellow acoustic character that gives a realistic sound to some instruments.




  • VSAT88VSAT88 Posts: 508
    Talk to the king of wood @F1nut ;)

    ^^ ^^^
  • VSAT88VSAT88 Posts: 508
    Viking64 wrote: »

    Jessewood was the original name for Hollywood... though Jesse's wood is now highly sought after on the west side of town.

    "If you drop your wallet in West Hollywood, you better kick it to Beverly Hills before you bend over to pick it up." :p

    LORDY !
  • VSAT88VSAT88 Posts: 508
    cortico wrote: »
    Thanks all for the useful comments B)

    Here is a pic of the crossover, pretty minimalistic 3 inductors and a cap and the woofers numbering... Sound is decent acoustic instruments have pretty good realism.

    Going back and forth between this and my restored and upgraded CRS, the CRS sound smoother but seem mid scooped in comparison.
    plj6a5d6rjes.jpg

    u46x5lttepk9.jpg



    Those woofers look a lot like the Norman 10's I had. Rubber surround an all. The crossovers were very simple as well.
  • corticocortico Posts: 316
    edited October 1
    VSAT88 wrote: »
    cortico wrote: »
    Thanks all for the useful comments B)

    Here is a pic of the crossover, pretty minimalistic 3 inductors and a cap and the woofers numbering... Sound is decent acoustic instruments have pretty good realism.

    Going back and forth between this and my restored and upgraded CRS, the CRS sound smoother but seem mid scooped in comparison.
    plj6a5d6rjes.jpg

    u46x5lttepk9.jpg



    Those woofers look a lot like the Norman 10's I had. Rubber surround an all. The crossovers were very simple as well.

    I read that they were made by Audax, other information on these is inexisting. I am lucky mine are in mint condition, I foresee many trial and error if one fail
  • Yep2Yep2 Posts: 778
    edited October 1
    Those woofers look a lot like the Norman 10's I had. Rubber surround an all. The crossovers were very simple as well.
    Norman 10's?
    Norman as in Norman, Oklahoma?
    Norman Labs?
  • corticocortico Posts: 316
    edited October 6
    Got the screen frames back from the shop!! I will paint it flat black paint before wrapping it with cloth.
    03xqro99qf54.jpg
    f900bpgzl5ez.jpg
  • corticocortico Posts: 316
    edited October 7
    Another update, I am not fully happy with the cloth. I think I found something a little heavier and more period correct.
    2g4lzpzt3vpo.jpg
    pjflfxsgyc04.jpg
    jiccaol94hbi.jpg
  • looks great from here.
    a quick google yielded
    https://www.acoustimac.com/dmd-acoustic-fabric
    Studio 2 equipment;
    Yamaha a-s2100 Amp, CD-2100 CD player, T-S500 tuner
    Loudspeakers: Harbeth p3esr, Polk RT7
    Cables: Aural Harmony Sonnet Interconnect II, WireWorld Equinox 7 speaker,
    Black Cat silverstar 75 ohm digital, Signal Digital Power Cord, PS Audio Perfect Wave AC-3,
    Pangea SE14, Voltz supplied interconnects
    Optional: Arcam DV88 DVD/CD (HDCD) player, Polk SDS-400 speakers
  • Tony MTony M Posts: 3,315
    edited October 7
    Beautiful speakers.
    I love finding older rare speakers in great condition or close to it.

    The instrumental " Riviera Paradise " by Stevie Ray Vaughn you played in your video was a song I used for years as a demo to show off Polk Audio speakers and some other kinds once in a while. But that instrumental on my SDA-SRS2"s is PHENOMINAL or SPECTACULAR ! People would ALWAYS ask me after playing it, "Who is that again and the name of it ?" It's a very, very well recorded instrumental !!
    Most people just listen to music and watch movies . I am glad to be a part of a select group that tries to take our auditory and visual senses to a higher level: we EXPERIENCE them.... GOT SDA?... Got TFM ?
2
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