Ideas on Upgrading S7R

[telynau]

I have some S7R speakers on the way and would appreciate opinions and ideas on how to use/upgrade them. The cabinets can't easily be restored to original condition (they have been painted and banged around a bit), so I am open to non-period or even modern component upgrades.

On the "traditional" side, I have identified the following possible paths.

1. Have the original components checked out/repaired (e.g., caps in xover) but leave the component inventory as is: LE15A; PR15; LE85; HL91; LX5

2. Use original components except upgrade HL91 short horn to H92/2312 long horn

3. Upgrade to S8R: LE15A; PR15; 375; HL93; 075; LX5; N7000

Here are a couple non-traditional paths.

4. Use original boxes and woofers but upgrade LE85/HL91 to a completely different driver/horn combination to handle 500Hz on up. Thinking broadly, this could include a wood horn with or without a ribbon tweeter, or something like a Great Plains Audio 902 compression driver with a 511B or Mantaray horn.

5. This is probably heresy on this forum, but I could even see using the boxes and woofers as the low end in a Dick Olsher Basszilla set up with a Lowther midrange (and ribbon tweeter if desired). I have a pair of Lowther PM5A's sitting around and the Basszilla uses them in open baffles on top of the woofer cabinet.

I am a hobbyist with a number of different vintage and modern speakers (e.g., Quad, Bozak, Alon, Altec, Lowther back horns), so I am not averse to a classic 60's JBL sound if that is the best use of these speakers. That is probably comparable to the kind of sound I get from my Altec Flamencos, though hopefully I can improve upon the bottom end with the S7R's.

If I had really nice original cabinets I would just go ahead and upgrade to the S8R configuration because it would be better sound while retaining authenticity.

But as I indicate above, a full cabinet restoration doesn't really make economic sense here, so what I am really out to do is have fun with the big cabinets.

I am a mostly tube (including triode), and classic amp kind of listener, though I do use Audio Research solid state and modern McIntosh 275 Mk. IV's on my Bozak Concert Grands, for example. I like vinyl a lot, but I also use an Apple Macbook and Wavelength Audio Cosecant DAC as a digital source. I listen to rock, folk, jazz and classical music, so the demands on the speakers are pretty varied.

I know that this is a pretty shy group, so please screw up your courage and give me your honest opinions.

:barf:

Regards, James

[Robh3606]

I know that this is a pretty shy group, so please screw up your courage and give me your honest opinions.

:rotfl: :rotfl: :rotfl:

As far as your speakers, I don't think the 2312 will fit. You will know when you measure them up. Traditional to an S8R is nice but you could also just go the 075 only route cause the 375 upgrade path will be expensive even using 2441 cores with new diaphrams. You could also go with a more modern compression driver. If you decide to go the nontraditional route you can open a thread in DIY.

Rob:)

[Zilch]

LE85 on H91 does not support 500 Hz, and not 800 Hz very well, either. H92 is good to 800 Hz, but I believe you'll have to punch the LE 85s out the back of your cabinets a bit to fit. You need 14-5/8" behind the front baffle. Not a big deal, since your cabinets are thrashed; it can be done skilfully.

With either horn, you're significantly lacking VHF. That means add a UHF driver - 077/2405 is what most would recommend, probably. Then, what have you got? L300, basically, so you build the 800 Hz N333 equivalent crossovers posted in these forums.

I think LE15A will play 800 Hz fine, but 2235H would be a likely woofer swap at some time, and you can have fun retuning the passive radiators as required for them.

I have some radical two-way approaches to offer, as well, but let's see what others come up with here first.... :thmbsup:

[jandregg]

The s7r is a nice speaker. If the cabs are in that bad of shape you want to make sure that the cabinet is airtight. The passive radiator needs a sealed box to do its job. Also check that the passive has two detatchable cardboard disk held on by a screw on the back. There is a cardboard disk glued to the back, and then there should be two cardboard disk held on only by a screw. Ifr these are missing it will degrade the sound.

Listen and you may find that you like what you have very much. It will go to 16k with the oldest diaphram and out to 20k with a later diaphram. The le15 was the top of the line for many years and the le85 was in production near 40 years. Clean it up, tune it up, turn it up. You just may find that you are very happy.

John

[Zilch]

It will go to 16k with the oldest diaphram and out to 20k with a later diaphram.Show us, please, John.

LE85 WILL go to 20 kHz with compensation, but it's a fruitless endeavor using the exponential horn/lens, which beams extremely in the vertical dispersion.

That combination also exhibits undesireable rising response in the upper midrange:

http://audioheritage.org/vbulletin/showthread.php?p=135642#post135642

It rolls off at ~12 kHz, but is already quite beamy at that frequency:

[Robh3606]

This a raw curve no network for a 2307 mounted to a 2425 with an Aquaplased Titanium diaphram . Above 10K it rolls off quickly. The red is unsmoothed the green is 1/3 octave.

Rob:)

[Zilch]

2426 similar:

[jandregg]

I never said it was perfect. And yes, I do have the 077 on mine. But I enjoyed the s7r before the 077. And I am still enjoying it with some modifications added over the years because I like playing with it. Zilch is still looking for the perfect horn. Some people enjoy the music.

John

[4313B]

Zilch is still looking for the perfect horn.It's nice to have a quest. Especially one that will have the same outcome as a good (?) game of Space Invaders on the Atari 2600.

[Zilch]

It's nice to have a quest. Especially one that will have the same outcome as a good (?) game of Space Invaders on the Atari 2600.Some folks still quite content playing Pong or PacMan, apparently.

[I never mastered either of 'em.... ;) ]

[4313B]

I hated the game because I like to win.

Mongol General (http://www.imdb.com/name/nm0593052/): What is best in life?

Conan (http://www.imdb.com/name/nm0000216/): To crush your enemies, to see them driven before you, and to hear the lamentations of their women.

Space Invaders didn't allow for such a wonderful experience.

[Zilch]

http://audioheritage.org/vbulletin/showthread.php?p=6001#post6001

Some members here are also working on trying new 3" diaphragm (1.5" exit) 243x drivers on a truncated exponential horn. The long H92/2312 creates significant time alignment difficulties.

This may be a better solution, additionally affording the opportunity for a beryllium midrange (2435HPL). Watch for updates....

[4313B]

http://audioheritage.org/vbulletin/showthread.php?p=6001#post6001

Some members here are also working on trying new 3" diaphragm (1.5" exit) 243x drivers on a truncated exponential horn. The long H92/2312 creates significant time alignment difficulties.

This may be a better solution, additionally affording the opportunity for a beryllium midrange (2435HPL). Watch for updates....I'm not sure why you guys constantly push the 2435HPL when it is nearly twice as expensive as the nicer looking 435Be. And it isn't aquaplased.

[Robh3606]

I'm not sure why you guys constantly push the 2435HPL when it is nearly twice as expensive as the nicer looking 435Be. And it isn't aquaplased.

The bottom line. You can't get 435's on Ebay for $200 a pop. I doubt anyone hear who has them has ponied up for JBL Pro's rather expensive asking price of $1300+ a driver. If I didn't already have my 2435's I would have purchased the 435's new but all my play money has already been spent on a second pair and software. I think's it more about what has been available over the past year than anything else. I was real surprised no one ordered a pair.

Rob:)

[4313B]

The bottom line. You can't get 435's on Ebay for $200 a pop.Ah! I never look for them so I wouldn't know about them on eBay.

I think's it more about what has been available over the past year than anything else.Then there's that...

[telynau]

Thanks to all who replied to this thread, but I ended up not getting the S7R speakers.

I went to pick them up in Manhattan, met the seller (very nice guy), looked the speakers over and tested them with the Stereophile test CD 2 (drum solo, acoustic guitar solo and organ). The foam around the woofers was rotted, so there wasn't a lot of bass, but the passive surrounds were in excellent shape. The LE85's sounded OK and the lenses were intact.

What gave me pause was the cabinets, which were a big part of the attraction of the speakers for me. I had suspected the cabinets were built from 8 cubic foot JBL plans and not JBL-built cabinets, but the seller had emphasized how heavy and solid the cabinets were. As it turned out, the guy who offered them on Ebay was a friend of the actual seller and somewhat overstated the construction of the cabinets. Although they were decently made, they were not anything like the cabinets on my Bozak Concert Grands or even the cabinets on my Altec Flamencos in terms of weight, solidity and ultimately inertness. I believe they were made out of good quality 3/4" (7 ply) plywood. And as I indicated above, they were not in great cosmetic condition.

During my hands and knees, close up inspection of the cabinets and speakers the owner, who genuinely loved these speakers (they were being sold due to space and WAF considerations) commented twice that if I had any hesitation at all about the speakers he would be happy to keep them. The third time he said it I told him I would take him up on his offer.

So we parted amicably and I am back to ground zero on a JBL based speaker system for my collection.

Thanks again to all for the recommendations. After the many hours of reading I have now done on posts in this forum, I think I will be most interested in the two way DIY project Guido and Zilch are apparently working on.

I have a local cabinet maker who can build anything I need in the way of cabinetry. For what it's worth, I have a corner in my family room (15'x20' with cathedral ceiling) has been begging for a "big" mono speaker system for years. One of my thoughts had been to use the two 8 cubic foot cabinets from the S7R speakers as the woofers for this system. As a mono system, I need it to move a lot of air.

Anyway, I will move this over to the DIY forum from here on.

Regards, James

[SUPERBEE]

Find a couple of gutted Olympus cabinets and go to town!