[Jay Bee El]

Does anybody have any experience with these?  The ones I have were built from a 60's vintage component kit.  The cabinets are similar (35.5" wide and 26.5 tall) but they're custom and they are built like tanks.



They are in really good working order but I don't think I have them paired with the right amp.  I have a Marantz 2275 driving them right now.  I'd love to hear any sugestions on what I might be able to find on a budget that would be better.

I have some more modern solid state (Adcom 555/Rotel RB870BX both with nice preamps) stuff on hand.  No tubes or anything like that and I doubt they are in the budget at this time.

Any thoughts, ideas or info would be helpful.

Much thanks.

[Jay Bee El]

Anybody?

[audiomagnate]

Why not try an affordable tube amp, like a modded console pull? They really were designed for vintage tube amps with their low damping factor, moderate harmonic distortion and soft character. Either that or a good solid state amp and an eq.

[Sparky15]

Jay

I worked for a JBL authorized dealer ( both JBL's home audio and pro sound reinforcement lines ) from 1976 to 1980 and was trained as a JBL repair tech at the Northridge CA plant.  These were a few years before my time, but the drivers themselves were still available and being used in current models.  I did repair a pair with blown HF 075 drivers. We gave them a 30 minute listen test and they put out bass that you felt right in the gut!  Also very dynamic, but like most JBL's of the era, can get shrill with certain material and amplification.

If you don't already know, one of the 15" drivers is a passive radiator to extend the bass.  Here are the specs:

3 ways, 3 loudspeaker passive radiator scheme, floor type
A. Bass: 38cm ( 15" ) cone type (LE15A)
B. Passive radiator: 38cm  ( 15" ) cone type (PR15) 
Mid range: Horn type (375+HL93)
Highs: Direct radiator (075)
Cross-over Network: LX5, N7000

Cross over frequency: 500Hz, 7000Hz
Impedance: 8 Ohms
Sound pressure level   :95dB
Max input: 125W
Dimensions: Width 1020x height 670x depth of 510mm

I had the L300 Summits for a few years, which were kind of a smaller version of the Olympus, less the passive radiator and a newer version of the high frequency and the 15 " bass, but pretty much the same performance. Great rock speakers!

They are very high efficiency speakers and a nice 25W tube amp or a warm sounding solid state would be likely plenty of power in a normal room.

Have these been worked on to your knowledge?  Cross-overs may need some replacement parts and the 15" speaker cone surrounds may need replacement, if not perhaps a whole new re-cone job which will replace the entire cone and the spider, which is the inner cone suspension which centers the voice-coil in the gap and drives the cone from the magnet.

Good luck to you!

[rcag_ils]

I always wonder what these vintage speakers sound like with the tweeters mounted so low. I am restoring a pair of Bozak, they are the same way.

[Wayner]

My friend has a pair of JBL C61 or C71?? at his store. They are also double 12" woofers with midrange and tweeters from the L100. The speakers are also made into left and right had. One of the woofers is a passive radiator. You have your orientated correctly, so that the silver driver is on the inside (not the outside).

[Sparky15]

On the amplification you already have, the Marantz 2275 @ 75wpc @ 8 Ohms is plenty of power, and it leans towards a warm sound which should flatter the JBLs.  However, a high damping factor can add a little difference on tightening the low end, and the Adcom 555 has a very high one, along with enough RMS power to blow the speakers out of the cabinet!.

You mentioned that you don't think you have them paired with the right amp.  What are you hearing to make that statement, and what speakers have you been using? If you by chance are not use to hearing a horn type driver producing the mid and upper frequency range, they can generate plenty of peaks in their response and get shrill sounding.  Back in the day, when graphic equalizers were popular, we used them quite often with the big JBL's to tame those horns peaks, yet not lose any of that great JBL dynamic and lively sound.

[Jay Bee El]

On the amplification you already have, the Marantz 2275 @ 75wpc @ 8 Ohms is plenty of power, and it leans towards a warm sound which should flatter the JBLs.  However, a high damping factor can add a little difference on tightening the low end, and the Adcom 555 has a very high one, along with enough RMS power to blow the speakers out of the cabinet!.

You mentioned that you don't think you have them paired with the right amp.  What are you hearing to make that statement, and what speakers have you been using? If you by chance are not use to hearing a horn type driver producing the mid and upper frequency range, they can generate plenty of peaks in their response and get shrill sounding.  Back in the day, when graphic equalizers were popular, we used them quite often with the big JBL's to tame those horns peaks, yet not lose any of that great JBL dynamic and lively sound.

Much thanks on the response.

Have made some headway with these.  The Marantz is ok and more than powerful enough.  I adjusted the crossovers on the back of the speakers and the sound is less shrill with rock music than it was.  Jazz sounds very good and detailed.  Listed to some Art Blakey this am and it was nice.

I'll post some more pics of the crossovers so you can see what I am talking about.  They are pretty bizarre, but in amazingly good shape.  Not a hint of rust or degradation.

[script56]

Those JBL are pretty cool.  I have a pair of 075 tweeters.  They do sound somewhat harsh compared to newer components.  They are nice from a distance.