AK teamwork = a crazy pair of Fulton Modular J's with RtR ES tweeters

Susurus has been on the lookout for these RtR electrostat tweeter modules, and last weekend he spotted a listing on Seattle CL for a pair included as part of the Fulton Modular J system speakers. I was not familiar with these speakers but I had seen and heard these types of RtR estat panels on a pair of Infinity 2000a's last year, and Susurus brought some to the AK get together last spring.

The Estat panels are exactly the same as referred in this post (with attachment) last year by Tom Brennan: http://www.audiokarma.org/forums/showpost.php?p=994401&postcount=3

Susurus emailed me, and we discussed on the phone how to arrange a grab for him, tips and tricks for visual inspection of the Estats. The seller claimed he had not used the Estats.

I sent an email to the seller, didn't hear anything for a day, then on Monday morning the seller gets back to me - he was working all weekend and was just starting to go down the list of replies, starting with mine. I called him back right away, and setup a meeting later in the day.

I visually examined the panels against S's guidelines and they all checked out. No signs of tampering, screws all match and look like they’ve never been touched. True enough the inline resistors / “clear” sleeves were dirty/rusty looking but nothing cracked or obviously broken / burnt. Fuses were intact. The plugs are old brown lamp cord style – they look original and do not look polarized to me.

My eyes didn’t detect any issues with the estat panels. See the pictures. The speakers (model 80 and model 120 bass cabinet) were hooked up to the seller's Denon BPC receiver with a Yammie TT for source. I verified output from all the drivers. The Denon was so weak (or maybe it was a low output phono cartridge) I really couldn’t tell how good the speakers sound – couldn’t distinguish much low or high frequency from his source. The Cabinets have light scratches on all nearly surfaces of the veneer but look like these go away with tung oil and light sanding / steel wool. There are a couple of dented corners on the big bass cabinets.

He got these from an audiophile brother in law years ago. He and the wife (both in their late 60’s probably) have moved with it several times, and he’s tired of moving big speakers (the bass cabs are probably 75 lbs). He has had Mc gear in the past – not an audiophile and he said several times that he just doesn’t care about perfect sound, good enough sound is ok with him. …but he’s benefitted from friends and family who are audiophiles with their hand-downs. He had the sense to be afraid of the Estats, and has left them alone. I got good vibes from this guy – he appeared to be very fastidious with how he had the gear setup and how he handled it too. He appeared to be happy to see it going to someone interested in it. He thought it was cool that he could pass along the original spec sheet from Bob Fulton - a 1 page two-side mimeographed page.

So, these are Susurus' speakers and Steve has a ton of research and links on these things. We are going slowly with the Estats, want to make sure they are properly charged, played carefully, etc. - I haven't had time to look at them so far this week, and the first question I've hit is where the EFF are the speaker wire terminals on them?

I'm really looking forward to working with Steve on these, putting them through their paces. I don't have room for another pair of speakers, but I was happy to make room and I'm happy to store them here until Steve can pick them up. :thmbsp:

I have a handful of pictures - I'll link a few here and more in a follow up post if there's any interst:

I had looked at those several times as well, they were posted on another site. Interesting setup.

Good work Dick,
Once again helping a brother out,They look bitchin!

Sluggo said:

Good work Dick,
Once again helping a brother out,They look bitchin!

Click to expand...

Yep they are wild, aren't they? apparently Bob Fulton went through ALOT of variations and modifications on these. Stereophile magazine reviewed them extensively, this configuration apparently retailed in the neighborhood of $3k.

SpeakerLabFan said:

We are going slowly with the Estats, want to make sure they are properly charged, played carefully, etc. - I haven't had time to look at them so far this week, and the first question I've hit is where the EFF are the speaker wire terminals on them?

Click to expand...

Never mind, I just noticed the RtR modules have the speaker wire "hard wired" - it was wrapped up with the power cord so I didn’t notice earlier. Doh!

Three banana split sundae salute to SpeakerLabfan for making this happen!

This is a rather rare set--would like to hear if AK'ers have heard them.

Briefly, first J. Gordon Holt of Stereophile magazine raved up, down, and sideways about these--to the point of keeping them as his 'reference' with which he compared all others.

Sort of what do you get if you wanted to preserve the sweet tonal quality sound of a Dynaco25 but seamlessly add true full range?

Sounds simple in principle, but the 'seamless' part...it's a killer from maniller.

Bob Fulton, to make a stab at this goal, integrated the E-stat array and a >6 ft^3 subwoofer (down to the low pipe organ bass notes--subs were called 'infrabass' at the time). One website talked about FMI woofers having multiple drivers or downward firing, but I've not yet found a pic).

TAC has a pic with a different bass cab and the very large grill hood. Either the stacked jumble look or imposing monolith look--no WAF awards coming.

Crossed the E-stats at 7500 Hz, ambitiously lower than the 12000 cutoff supertweeters that Dahlquist (piezos) and later HPM-100s (polymer) were.

All Fulton J sets would need recaps by now--plus there were frequent QC issues to begin with.

Bob Fulton was on a mission (cf Blues Brothers!) and tweaked these to death, and the early ones with the AlNiCo drivers are reportedly the best.

More later.

Careful with vintage E-Static panels--if it appears they've never been tampered with, maybe it's best to use a variac for first start-up. If there's missing or unmatched screws holding them in the frames, hmmmm. Could be a red flag. (Infinity used roundhead aluminum screws there).

But my main danger list goes like this:

(1) Dust on the e-stat panels.

I just blow with my mouth. High-pressure air from a compressor could rupture the membrane! Never ever used canned air--the additives will ruin the membrane and there's no way to fix it. (All canned air has additives--don't believe what the label says!) Plus the freezing on expansion kills the panels too.

There's a very small gap between the stators and the membrane. And both sides can have dust shorting out (one reason these are so good is they are push-pull, so there are wires on both sides). But if there's still visible debris I use a soft, natural long-haired artist's brush, and the lightest feather touch imaginable.

Membrane is only .001 thick or something and not as strong as modern Kaptan and has a lower glass transition point (maybe only 400 degrees).

(2) Loose nut connectors to the E-stat panels --they are always loose. But over-tightening breaks them for good. Ack.

(3) The high voltage wires may be magnesium(?), I would not replace them without very careful investigation. Unobtanium?

(4) The in-line resistors may look funky inside those clear sleeves which are a rust trap.

(5) high voltage circuit--can have transformer hum and still work (two of my e-stat hybrids here do). Tightening down the transformers may help some. Bigger problem if there's a 'snap' or 'crackle' sound, which means a real shorting.

(6) fuses - may be visible from the open back of the module.

(7) That circuit should have used a polarized plug. It works better one of the ways so you test both. Plus you don't want reverse phase cancellation! The AA battery phase test is useless here...

(8) Don't connect speaker wires with the amp turned on.

If you've got more tips, I'd like to hear them.

There wasn't exact science on the naming of this constantly changing effort. FultonJ, J-modular, E-modular?

Crossovers nodes at 83, ?, ?, 7500 Hz.

Modules for this one:

bass: FMI-120 E-woofer.

12" pleated Hooray! in a 18" square 34" tall sealed cab.

mids: FMI-80 (also sold standalone)

8" woofer, RtR or CTS. The later 6" Peerless is not supposed to be quite as good. FMI-60 was the later standalone.

HF : FMI-6 E-stat array (partial barrel or circumaxial) in a open-back channel (looks like the RtR ESR-6 but could have different components).

Yes, it does look a lot like an RtR ESR-6. Only difference I noted right off is that the grills seem to be held on with velcro on the FMI-6 while my ESR-6 used long narrow staples.

If it were up to me, I'd try to cross those electrostats down lower than 7.5kHz. My ESR-6 tweeters came with 1.2kHz crossovers built in, but I normally crossed them over at about 2.5k or 3k.

As far as I know, there are three protective devices on these tweeters. First, a 1/8A fuse in line with the primary of the power transformer. Next is a circuit breaker in line with the primary of the audio transformer (of unknown rating). Finally, there is a spark gap on the secondary of the audio transformer. In my experience, the circuit breaker is prone to fail with time. One of mine got quite touchy and would need to be jiggled quite often - without being overdriven. Replacing it helped.

The RtR electrostats have found their way into a couple higher-end speakers. The first generations of Wilson's WAMM used the ESR-15 essentially unaltered. I used mine for many years and was completely happy (other than some arcing on a couple panels after they received the output from the business end of a shotgun from my ex-wife's boyfriend, these things are pretty indestructible).

Thanks House de Kris. I'll take your advice. Same spark-gap on my (4-panel) Infinity 2000A's.

Those are crossed at 1800 from ~3.5" Philips whizzer-cone mids. I was gonna kick it up a bit higher and put in ScanSpeak Revelator 4.5" mids.

I'll try to look up what my RtR E400 uses but they are the larger 8x8 section panels. The overall radiant PI/2 area may be the limiting factor for the lowest viable cross node.

What matched up best with your RtRs panels?

All shotguns must be checked at the door, please. istols: Yikes~!

House de Kris said:

The RtR electrostats have found their way into a couple higher-end speakers. The first generations of Wilson's WAMM used the ESR-15 essentially unaltered.

Click to expand...

Like my ESS Superquads...

yep the Fultons may be rare to find in working shape, but your ESS are almost mythical. I forgot how many panels on the back?

The alternating portrait-landscape arrangement is interesting too. If the stators on the horizontal is intended to be right side up, my RtR E400's are sideways.

Susurus said:

What matched up best with your RtRs panels?

Click to expand...

You mean as far as amplifiers? In all the iterations of the system these were in, it was always a multi-amp affair, either bi-, tri-, or tetra-amped. At the time, I was into the tube amp sound. I didn't have many tube amps to try, but I did prefer my Dynaco ST-70 to any solid state amp I had for them. I borrowed an ARC 60WPC amp (don't recall the model), which I really liked, but couldn't afford at the time.

Sorry, guess this wasn't much help.

These Fultons are quite possibly my cup of tea in a major way! Fulton seems to have refused to compromise midrange tone for higher and lower FR extension. These may encompass a greater volume of the solution space I seek.

Background: I'm a natural-tone midrange freak. Dahlquist, Bozak, it has to make cellos and vocals breathe in living color.

I want the transient response of planars for Brazillian and Ethiopian percussion, the coherence of KEFs' coax. (Haven't heard Tannoys yet... but that could quickly invoke comparisons with the old adage "a boat is a hole in the water into which you pour money". You pilots know a similiar one... :yes: :smilemad:

I want epic bass (Yes or ELP synth) on occasion (Speakerlab7's strong suit).

And my two E-stat hybrid pairs have the most satisfying, transparent HF in this house so these 6-panel modules are a known sure winner.

Airy, etherial. Okay downright ephemeral. Shimmering. (Not satisfied with this perversly profuse plethera, this adjectival torrent? Click here. It doesn't actually go anywhere, I just wanted to see you click here. awprint:

So of course I listen to different genres on different systems. No single one is every chocolate flavor in the box.

(Gump pic goes here)

Some more digging on these:

1977-1980, which coincides nicely with my favorite era for much of my gear...

The best ever Fulton (Premier? or a different J), could have used the same mid and upper modules as this 'E' setup. I've reached another pinnacle piece. That would make four for me?

The largest FMI woofer cab claimed down to 14 Hz. (-?dB). It had 3 woofers in each cab.

The tweeter panels themselves are actually pretty resilient, but the electronics backing them up racked up poor MTBRs. Infinity abandoned them but couldn't get over the sound; invented the famous EMITs in their place.

Fulton was a musician first. The piano strings had to sound like music. AR and Vandersteen have had fooled ya demonstrations with the live players halting in mid-stanza, and the speakers take over. The audience goes oooh, ahhh.

-------
After SLFan has had time to show these through its paces, anybody in his area coming down Portland way consider a passenger--Pony Express?
----------


I have not yet gotten horns to do the right thing. My Altec 511B's and Klipsch rule on Dynamics, but maybe I'll turn some Edgars someday that don't ring or choke up... the search continues.

:thmbsp:

House de Kris said:

You mean as far as amplifiers? [...]

Sorry, guess this wasn't much help.

Click to expand...

It is to me. Thanks!

Susurus said:

These Fultons are quite possibly my cup of tea in a major way! Fulton seems to have refused to compromise midrange tone for higher and lower FR extension. These may encompass a greater volume of the solution space I seek.

Background: I'm a natural-tone midrange freak. Dahlquist, Bozak, it has to make cellos and vocals breathe in living color.

I want the transient response of planars for Brazillian and Ethiopian percussion, the coherence of KEFs' coax. (Haven't heard Tannoys yet... but that could quickly invoke comparisons with the old adage "a boat is a hole in the water into which you pour money". You pilots know a similiar one... :yes: :smilemad:

I want epic bass (Yes or ELP synth) on occasion (Speakerlab7's strong suit).

And my two E-stat hybrid pairs have the most satisfying, transparent HF in this house so these 6-panel modules are a known sure winner.

Airy, etherial. Okay downright ephemeral. Shimmering. (Not satisfied with this perversly profuse plethera, this adjectival torrent? Click here. It doesn't actually go anywhere, I just wanted to see you click here. awprint:

So of course I listen to different genres on different systems. No single one is every chocolate flavor in the box.

(Gump pic goes here)

Some more digging on these:

1977-1980, which coincides nicely with my favorite era for much of my gear...

The best ever Fulton (Premier? or a different J), could have used the same mid and upper modules as this 'E' setup. I've reached another pinnacle piece. That would make four for me?

The largest FMI woofer cab claimed down to 14 Hz. (-?dB). It had 3 woofers in each cab.

The tweeter panels themselves are actually pretty resilient, but the electronics backing them up racked up poor MTBRs. Infinity abandoned them but couldn't get over the sound; invented the famous EMITs in their place.

Fulton was a musician first. The piano strings had to sound like music. AR and Vandersteen have had fooled ya demonstrations with the live players halting in mid-stanza, and the speakers take over. The audience goes oooh, ahhh.

-------
After SLFan has had time to show these through its paces, anybody in his area coming down Portland way consider a passenger--Pony Express?
----------


I have not yet gotten horns to do the right thing. My Altec 511B's and Klipsch rule on Dynamics, but maybe I'll turn some Edgars someday that don't ring or choke up... the search continues.

:thmbsp:

Click to expand...

Yep, it would be great if there's an AK'r who is covering the trek between Seattle and Portland, willing to transport these for ya.

this is an interesting read. I hope to have some time this week to check these out more.

I first heard the Fulton J back in the early 70's I beleive in a Bay Area dealer.....I was never the same. It would be interesting to read the spec sheet instructions. I have often thought maybe some day I would come across a pair....just to have. Is there a website that has info on the Fulton's??? Anyway...I am envious...you have a piece of audio history there...and look foward to your progress and experience with the J's.

Very few sites with info on these, after the original B.A.S. & Stereophile magazine stirrings praising it, I haven't found a lot.

Van Alstine's obit says:

Bob Fulton was best know among audiophiles
for his stupendous Fulton J Modular loudspeaker
systems and his FMI 80 mini-speakers,
both which set new standards of musical
performance in the 1970s when the trend was
going the other way – from the good early
designs of Bozak, AR, Klipsh, KLH, etc. to the
whole mess of department store oriental "stereos"
that clutter up closets and attics everywhere
today.
Bob's efforts then were a key in revitalizing the
entire high end audio industry and were a
bright light showing that the music is the object
at a time when many were forgetting that.
But more important than Robert Fulton's products
was his lasting contributions as a teacher.
More than anyone else, he knew how to listen
– how to hear and understand what was musically
right and wrong with audio playback
components, and more than anyone else, he
taught others how to listen. Those of us that
were personally exposed to Bob's knowledge
and teaching over the years are much richer for
the experience.
There will never be another Robert Fulton, but
his contributions will never be forgotten.

Click to expand...

Susurus said:

Very few sites with info on these, after the original B.A.S. & Stereophile magazine stirrings praising it, I haven't found a lot.

Click to expand...

Susurus,
I listened to several pairs of them back in the day, including a pair that were cloned. The clone was as good as the real J's IIRC. One of the guys that was in on it is still involved in audio, so I'll contact him and see if any information can be gleaned. It's been nearly thirty years, but he's pretty bright (OK, he's really bright!) and could probably suggest something or other that may help.

BTW: How many here have actually seen, or inspected, a Fulton J Modular speaker?
I seem to remember that the crossover populated 2 or 3 large stacked PCB's and was scary in it's complexity. For all that, they sounded to my (then) young ears well nice indeed. I'd love to hear a pair again and see if my lingering memories are accurate

Best Regards,
TerryO

Fast996 said:

I first heard the Fulton J back in the early 70's I beleive in a Bay Area dealer.....I was never the same.

It would be interesting to read the spec sheet instructions.

Click to expand...

I have often thought maybe some day I would come across a pair....just to have. Is there a website that has info on the Fulton's??? Anyway...I am envious...you have a piece of audio history there...and look foward to your progress and experience with the J's.

Click to expand...

I did a scan of the Fulton J instructions spec sheet with x'd out and handwritten updates (probably from Fulton himself?). If any AK'rs are interested, send a PM with your email, and I'll send it along. :thmbsp:

TerryO said:

Susurus,
I listened to several pairs of them back in the day, including a pair that were cloned. [...]

BTW: How many here have actually seen, or inspected, a Fulton J Modular speaker?

Click to expand...

That number is about to increment by 1.
An AK'er from this thread magnaminously offered pony-express passage for these rare (but rather bulky) pieces of audio history...

Many thanks!!

[...] I'd love to hear a pair again and see if my lingering memories are accurate

Click to expand...

I hope to have them in demo-ready condition if there's another quasi-local get-together...