[Stimpy]

FOR SALE: VMPS Supertower II a/R  -  (Salt Lake City, UT)  $2000

http://www.usaudiomart.com/details/649262138-vmps-supertower-ii-ar/









"Excellent condition. Awesome clean sound with SUPERB BASS,. New surrounds on Subs and passive sub. Modified tops to easily access passive subs for re-surrounding and damping changes. Circuitry allows bi-a ping with two amps. One can power lo's and one maids and hi's. Casters mounted to move them around cuz they're HEAVY. No other speakers can touch these."

[James Romeyn]

I love the history lessons James!  Please feel free to continue as much as desired!       Thanks!

Don't encourage me, I'll never get anything done around here!

The original Japanese JVC planar super tweeters are absolutely awesome, even by today's standards (for the top octave, they fall off rapidly <5k Hz...we had the FR graph at one time, they go above 20k), outperforming every later VMPS super tweeter except the RIBBON.  Every true ribbon (one exception) has a transformer because the diaphragm is pure metal w/ultra low impedance.  No transformer is a PLANAR w/diaphragm comprising a metal-coating over a non-metallic/usually polymer substrate.  The JVC outperforms even the much later spiral tweeter which is either a direct replacement or a clone of the old Genesis.

Only one ribbon I can think of employed no transformer, a British ribbon in Brian's huge and uber costly tower in the early/mid 80s.  The brand name escapes me and it's load impedance was <1 Ohm.  It was impossible to drive alone, required multiples wired in series.  I think Brian used 4 of them.       

VMPS super tweeters in descending performance sequence:

• FST w/transformer
• Original JVC planar ("JVC" stencil on magnet, tossup between JVC and Philips, former sweeter and more musical, latter a little more detailed and dynamic but higher distortion)
• Philips large black planar (just remembered this one, came after the JVC clones, very nice, less sensitivity and output than FST, sound improved with wave guides removed but looks drop from very nice to very not nice)
• Taiwan JVC clone planar, looks very similar but "Taiwan" stencil on magnet, a little less refined sounding, likely similar performance to later Black Foster planar and later still spiral planar tweeter, but all three sound a little different

[revg1952]

I agree with James, the original JVC ribbons are great, I am using a couple of pairs in projects I am doing very sweet and smooth!!!
Revg1952  (former VMPS dealer and Lover)

[Stimpy]

REPOST & PRICE DROP 

VMPS QRS 626 Single Perhaps for Center Channel - $25  Now $10 Bucks...!

http://kansascity.craigslist.org/ele/5486052907.html

"Doesn't work well. Text , call or email me."

VMPS QSR 626 - One Speaker Used As Center  -  (Independence, Missouri)  $250  BIN

http://www.ebay.com/itm/172123794416?rmvSB=true




"VMPS QSR 626 speaker. Single speaker. Used as center center. Seems to work very well. Paypal only. US bidders only."

[HAL]

Don't encourage me, I'll never get anything done around here!

The original Japanese JVC planar super tweeters are absolutely awesome, even by today's standards (for the top octave, they fall off rapidly <5k Hz...we had the FR graph at one time, they go above 20k), outperforming every later VMPS super tweeter except the RIBBON.  Every true ribbon (one exception) has a transformer because the diaphragm is pure metal w/ultra low impedance.  No transformer is a PLANAR w/diaphragm comprising a metal-coating over a non-metallic/usually polymer substrate.  The JVC outperforms even the much later spiral tweeter which is either a direct replacement or a clone of the old Genesis.

Only one ribbon I can think of employed no transformer, a British ribbon in Brian's huge and uber costly tower in the early/mid 80s.  The brand name escapes me and it's load impedance was <1 Ohm.  It was impossible to drive alone, required multiples wired in series.  I think Brian used 4 of them.       

VMPS super tweeters in descending performance sequence:

• FST w/transformer
• Original JVC planar ("JVC" stencil on magnet, tossup between JVC and Philips, former sweeter and more musical, latter a little more detailed and dynamic but higher distortion)
• Philips large black planar (just remembered this one, came after the JVC clones, very nice, less sensitivity and output than FST, sound improved with wave guides removed but looks drop from very nice to very not nice)
• Taiwan JVC clone planar, looks very similar but "Taiwan" stencil on magnet, a little less refined sounding, likely similar performance to later Black Foster planar and later still spiral planar tweeter, but all three sound a little different

Strathearn ribbons?

[James Romeyn]

Strathern ribbons?

Yes, thank you.  My google search failed.  That was the only VMPS true mid range ribbon, and it lacked impedance matching transformer.  But again, very difficult to drive @ .35 Ohm each.  Few amps today can drive even four Strathearn ribbons in series. 

My $1490/ea Hypex nCore NC400 Stereo makes 200/400/600W @ 8/4/2 Ohm, and can drive a 1 Ohm load. 

[Stimpy]

Strathern ribbons?

Strathearn Audio history.

http://zstereo.co.uk/2013/11/07/strathearn-sma2/

The Strathearn Planar Driver as used in the early Pre-IRS Infinity QRS.



Others.





Their main claim to fame was when Harry Pearson of The Absolute Sound, modified a pair of QRS speakers, due to his complaint of the bass not being clean and fast enough to keep up with the Strathearn midrange drivers, and Strathearn Emit tweeters.  HP added bass panels, from Magnepan, to create a hybrid speaker.  The hybrid creation so upset Arnie Nudell of Infinity, he created the IRS-III's, in response!  HP's hybrid looked similar to this.

[Stimpy]

Yes, thank you.  My google search failed.  That was the best sounding of all VMPS Ribbons, but again, very difficult with which to work.

Did Brian ever build a design using Strathearn drivers?  Plus, didn't Brian have the U.S. import rights for the Strathearn ribbons?  Or was that Dr. Michael Alan Marks, aka, the 'infamous' Magic Marsky?  He built the QRS/Magnepan hybrid that I pictured in my previous post.

[HAL]

Would have loved to try the Strathearn ribbon panels, but cannot find them anywhere anymore.

[Stimpy]

Would have loved to try the Strathearn ribbon panels, but cannot find them anywhere anymore.

I agree.  I'd love to hear them.  But, I've also read that the Strathearn panels were physically quite fragile.  Supposedly, just shipping the panels could cause damage. 

Me personally, I'd love to be able to buy some of Bruce Thigpen's Eminent Technology panels.  While not super efficient, they sound awesome.  There were even 3 pairs of the midrange drivers on a local CraigsList ad last Fall.  And they were the LFT-8 big mid drivers too!  The pricing was very good, but I had just blown my 'toy' budget on a new A/V receiver, a 4K TV, and a wall clock for my wife (gott'a show the love).  When I had money again, the panels were gone!   

[James Romeyn]

Did Brian ever build a design using Strathearn drivers?  Plus, didn't Brian have the U.S. import rights for the Strathearn ribbons?  Or was that Dr. Michael Alan Marks, aka, the 'infamous' Magic Marsky?  He built the QRS/Magnepan hybrid that I pictured in my previous post.

Brian had in the sound room for a loooong time a pair of his Strathearn true ribbon towers.  I presume the Strathearn covered from about 1k Hz up to beyond 20k Hz.  I'm virtually positive there were no tweeters.  IIRC each tower comprised two 6.5s and the ribbons, with offset/time aligned baffles, the 6.5s IFO the ribbons. 

Below the 6.5s was handled by VMPS Original subs, either Original or Larger models.  Two amps required, with John Curl designed small active LP only crossover > sub amp.  I think some custom weird as heck looking Curl 60W wood chassis Class A mono blocs > Strathearn main towers, w/insanely large and heavy John Iverson (not Stereophile author Jon Iverson) Electron Kinetics Eagle 7C > subs.

IIRC no HP xo > 6.5s, passive LP xo > 6.5s , and passive HP xo > Strathearn ribbons. 

Brian built only a handful of the model w/Strathearn mids.  At that time almost no amp could drive the 1.4 Ohm mid range load.           

Audio performance reminded me of the much latter STIII SRE w/BG's largest true ribbon mid above about 110 Hz.  (STIII SRE had superb audio performance but many service issues with the BG mid, for which BG refused warranty service, which lead to the Dynaribbon panels from Just Speakers (let's just say Brian got a super deal on those) in San Francisco, then the BG 8" planar mids, then the Neo 8" planar mids.)

Sorry, forgot the name of the brothers who ran Just Speakers, great guys.  Sadly, the store closed soon after one of the brothers tragically died of HIV, one of the early victims before the latter drug therapies arrived. 

Just Speakers had in the show room (in the middle of SF Mission District) an early pair of the costly (then $80k/pr IIRC) Dynaudio Consequence, huge rosewood towers w/inverted driver array, Iso Barik 12s IIRC, followed by MB, upper mid range, tweeter, etc.   

I very much like Thigpen's panels!  I'd consider totally damping the back wave, and for reverberant field rather use our $1850/pr AudioKinesis Space Generators. 

[Stimpy]

I just found this post for the Widerange Ribbons.  Pretty impressive!  Thanks to the OP!

Here's another brochure of a classic VMPS speaker - Widerange Ribbon. I first heard these at Clark Johnsen's huge loft (store) by the waterfront in Boston. They were awesome and massive. It was quite an experience.

[James Romeyn]

Very nice!  Good job! 

How many ribbons?  I can't read the spec sheet, even maximum size and brightness?  Looks like six in the image.  Six x .35 Ohm each is still only 2.1 Ohm in the mid range, a brutal load for most amps.  As per industry norm, the "3.0 Ohm Minimum" is a little, shall we say, optimistic.  Explains Brian's affection for the Eagle 7A and latter the Plinius SA250 mkIV (about 150 lbs, 250Wpc Class A).     

When I'm wrong, I go all out!  JVC super tweeter, dual 8s not 6.5s, and dual 12s in the tower.  Each baffle section holding the 8s and 12s is offset IFO the main baffle holding the JVC super tweeter and the ribbons.  The baffle looked busy.   

[DFaulds]

Apogee, arguably the most commercially successful speaker company that utilized primarily ribbon drivers, also had transformerless designs.  Large, hard to drive and expensive, they still have a very strong cult type following.  Unfortunately, like almost all large panel speakers, ribbons, planars or ESLs, most Apogees are probably no longer working properly.

Jack Caldwell had a design in the 80's sold through Audio Concepts (ACI) that utilized, I believe 3 Strathearns per side along with a woofer module.  I recall it was sold as a kit or a completely built system.  I'm sure I've still got the catalog laying around somewhere.  Caldwell was one of the kit designers that Mike Dzurko used.  I also remember he sold Bill Reed designs for a while as well.

[James Romeyn]

I'm very glad you mentioned the Apogee.  While typing I wondered why would their load impedance be so low if they had a transformer, which question you answered: they did not! 

Sold two Levinson No. 23 power amps to an M.D., who intended them in mono mode to drive his enormous and almost impossible to drive Apogee Full Range Ribbons, then rated 1 Ohm minimum.  Only heard the huge Apogee ribbons once or twice, likely driven by one of the other few amps that could drive them, huge Krell mono blocs.  Setup right they have a huge and unique presentation.

Over the years, since learning about the impact and importance of the reverberant field, I'm convinced that much of the most critical and desirable performance attributes normally associated with the largest, most costly, and most difficult to drive planar speakers, is the result of their reverberant field performance (when setup ideally). 

This opinion is based on decades of experience hearing everything from IRS III to Kimber's impossibly complex Isomike display with eight full range Soundlab 8' tall stats (and proprietary 4-ch recordings), to MBL (what could be described as a radial planar driver), to every contraption Brian designed, and our own $1850/pr AudioKinesis Space Generator accessory reverberant field speakers now. 

Proper and ideal reverberant field does more than provide that indelible sense of density and envelopment.  It also correlates to fine detail without the usual downside of increased listener fatigue.  Preeminent authority Dr. Floyd Toole says that the better is the reverberant field the better is perception of pitch center.  The ideal reveberant field (proper level, proper spectrum, proper delay) gives the listener a "second look" at the pitch, which increases and reinforces the first look via primary line of site output (front firing output). 

One audiophile told me his speakers "do not distort pitch," which opinion seems to contradict Toole.  The reverberant field directly affects pitch perception, and the better is the RF the better is pitch perception.     

One of the benefits associated with improved pitch perception (improved reverberant field performance) is to appreciate more complex music.  By improving the reverberant field one may notice an appreciation for musical programs previously found boring.  I have found that to be the case.

Lastly, related to Brian's huge bass-only towers, with drivers spanning from floor to ceiling.  Every time we set those up I was gob smacked how fantastic they sounded.  They presented an incredible depth of stage effect in the bass, and obviously audibly less distortion than even a pair of the Larger Subwoofer, no slouch in the low bass department. 

But since then I learned how the human ear is extremely low sensitivity for (high threshold) for THD in the bass range.  Dr. Bob Carver said, and I have heard confirmed, that humans can not detect a difference <100 Hz between 1% and 33% THD!!!!!!

This could be easily proved with a THD switch, and I'd sure like to see it confirmed.  If true, the marketing hype about subs with amplifier spec THD are exactly that, marketing hype.  The primary problem to be solved <100 Hz is not THD, it's the room modes, which is a time related problem.

Meanwhile, if it's true, and I suspect very much that it is, then why did and do Brian's 7' bass towers with four or six 12s sound so fantastic?  Ditto the IRS III, etc.   (BTW, Brian sold and we setup ST IIa/R at the home of the owner of the IRS III.) 

I think I know why.  The primary advantage is not lower THD, but the muting of the worst and primary bass mode, being the floor to ceiling frequency.  The natural trend of a floor to ceiling driver array is to damp this mode, which is the worst mode because it's usually the shortest (highest in frequency) and largest two parallel boundaries in the entire room (which also explains why you heard such good sound in most rooms with hugely vaulted ceiling).   

In effect, a floor to ceiling bass driver array is a mini-distributed array, centered around only one mode, the floor-ceiling bounce.  A true distributed bass array like our $3k DEBRA Distributed Bass Reflex Array damps all the modes within the room.   

[esprits4s]

Very nice!  Good job! 

How many ribbons?  I can't read the spec sheet, even maximum size and brightness?  Looks like six in the image.  Six x .35 Ohm each is still only 2.1 Ohm in the mid range, a brutal load for most amps.  As per industry norm, the "3.0 Ohm Minimum" is a little, shall we say, optimistic.  Explains Brian's affection for the Eagle 7A and latter the Plinius SA250 mkIV (about 150 lbs, 250Wpc Class A).     

When I'm wrong, I go all out!  JVC super tweeter, dual 8s not 6.5s, and dual 12s in the tower.  Each baffle section holding the 8s and 12s is offset IFO the main baffle holding the JVC super tweeter and the ribbons.  The baffle looked busy.   

I have one of these brochures and could scan it if there is interest. 

The specs read:
Midrange/Treble:  5/16" x 130" ribbon element, side-by-side traces, radiation height 69"
Supertreble:  3/16" x 2 1/4" ribbon

-Gary

[James Romeyn]

I have one of these brochures and could scan it if there is interest. 

The specs read:
Midrange/Treble:  5/16" x 130" ribbon element, side-by-side traces, radiation height 69"
Supertreble:  3/16" x 2 1/4" ribbon

-Gary

Very interesting! 

Extrapolating the math, looking at Brian's well done sketch and HP's design, each Strathearn ribbon is an estimated 12" tall.  69" alleged total ribbon radiating height/12" = 5.75, and it looks like six panels in Brian's diagram.

I read elsewhere the Strathearn presents a load impedance of .35 Ohm, which x6 in series = 2.1, 30% lower than Brian's "3 Ohm" spec.  My Hypex nCore Stereo NC400 could easily drive that load, but no other amp I ever heard of that weighs 8 lbs, cost <$1500 USD, and idles @ 4W.

I respectfully request a reprieve for mistaking Brian dual mid bass 8s for 6.5s.  Surrounded by Brian's 12s and 15s, 8s are easily mistaken for a smaller driver. 

As for forgetting the dual 12s near the floor: hey, I'm tall, and miss a lot of stuff near the floor!

I will never forgive myself for not bringing home from the Plant at least two of Brian's stand mount monitors which SOTA TT principal David Fletcher contracted with Brian to design.  Allen Perkins ex-SOTA plant manager and now principal at Immedia TT, designed the stunning cabinets.  Allen is a master craftsman and great jazz drummer. 

These were to be SOTA's answer to Dave Wilson's ground breaking and insanely expensive (for that time) WATT.  I can't believe I forgot the model name now.  If you see Perkins ask him if he remembers.

Brian specified his own poly 8", 8PR slot loaded/down firing, and Focal's T120F fiberglass inverted dome, which is so far superior to Wilson's preferred T120 Kevlar that I have no idea why Dave bothered with the Kevlar (FG rolls off smooth though admittedly sooner, Kevlar has large and audible resonance on top...now you know what you did no like about the early WATT, that and the thin bass/high cutoff requiring the subs, which later were mandatory). 

Gorgeous hard wood laminate, super thick panels, weighed over 30 lbs even though moderately sized, huge radius on every corner except the bass, satin finish, superb artisan cabinets.  Sloping front baffle.  IIRC the two side panel also sloped, narrower on top/wider near the base, but not positive about that, possibly parallel.  The back panel was vertical, almost positive.   

SOTA also designed custom enclosures for optional subs, similar enclosure design as the monitor, similar size and drivers as Brian's smaller subs.     

John Casler can volunteer if he saw these cabinets when he helped Shirley after Brian's passing. 

[BobRex]

It was the SOTA Panorama.  I sold these for a while and contemplated using them as my personal speakers.  But I could never get the tweeter to gel properly, it always stood out from the mids and screwed up violins, as well as pushed cymbals forward.  I ultimately brought a pair of Acoustic Energy AE1s (2nd gen, with biwire capability, at that point imported by Mel Shilling, if memory serves) because they integrated better.  I still use them in the garage.

[Stimpy]

Extrapolating the math, looking at Brian's well done sketch and HP's design, each Strathearn ribbon is an estimated 12" tall.  69" alleged total ribbon radiating height/12" = 5.75, and it looks like six panels in Brian's diagram.

I read elsewhere the Strathearn presents a load impedance of .35 Ohm, which x6 in series = 2.1, 30% lower than Brian's "3 Ohm" spec.  My Hypex nCore Stereo NC400 could easily drive that load, but no other amp I ever heard of that weighs 8 lbs, cost <$1500 USD, and idles @ 4W.

I found this on another Forum.  From Big B himself.

"...the Widerange Ribbons. Their minimum impedance was 3.5 Ohms, not a bad load. We did not employ the Strathearn transformers, but used ballast resistors instead to bring up the impedance."

[James Romeyn]

I found this on another Forum.  From Big B himself.

"...the Widerange Ribbons. Their minimum impedance was 3.5 Ohms, not a bad load. We did not employ the Strathearn transformers, but used ballast resistors instead to bring up the impedance."

As my deceased Aunt Celia would say, "...and there we are...," or, "...and there you have it...."  Mystery solved.  Of course, the series "ballast resistor" (approximately 1.4 Ohm) reduces output.

What was the sensitivity of the Strathhearn ribbon?