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

[SpeakerLabFan]

:thmbsp: ...for the AK I-5 Pony Express. Yep, at the appointed time, we met up at milepost 179 off I-5 and carefully moved them (along with a Luxman R-1040 in need of re-lamping and a pair of E-V Interface speakers) from my truck and into the southboud trailer.

Looking forward to your further research and observations on this unique speaker system.

 

[kfa888]

Just dropped them off an hour a go. :thmbsp: That was a LONG day.

 

[SpeakerLabFan]

Excellent! :tresbon:

 

[Susurus]

Until I get the other E-stat panel to work my observations are impaired.

However...initial impressions while they are fresh (subject to changes when I multi-amp).
The bass cab is way top-heavy. Could be the 3 boards in there, or the woofer mag is 40 pounds. The E-stat modules can be used on my Bozaks too.

And Stereophile says to use a tube amp. I don't have one, don't want one.

Part 1, mostly about the bass.

(1) It is unlike any I have ever heard.

Why? Well-matched elements work together better than my 2 other E-stat hybrids. That's like a grand slam.

Other systems I've heard either had one massive Velodyne powered sub that smeared the stereo image or created earthquakes but didn't distinguish between a string bass and electric. Or a pair of powered subs that created an artificial or difficult match to the unpowered side of the equation. I am not a bass expert but I am picky as heck.

Fulton's two large bass modules preserve the full range with low (to extremely low) compromise for low-midrange tonal quality. Like my Dahlquists, but with better dynamics and 'beyonder' full range.

Perhaps because the bass module is actually an acoustic suspension, >6 ft^3 cab, infrasonic (32-83 Hz, +-2dB). The next year's model made it down below 20. Was it more boomy? Don't know. Most every other system I have crosses the low node at 350-400. (DQs, Bozaks) or 700 (Speakerlab horn hybrids) or 1000 (Heresies). What do you cross the DQ bass module at?

Amazings were crossed at 100-120, but I never got the ribbons to hear them.

 

[Susurus]

Great gobbling gooneybirds Batman! These are intense! I may need to totally rethink and realign priorities...

Or if you prefer less hyperbole, just call it Part 2, initial impressions/ramblings

This is tweaker paradise. The xovers allow bypassing, detaching, triamping, all manner of tinkertoying. Since only my ears are the test equipment I can say less than I will later say.
:nono:

Til I can fix one of the tweeter modules I placed one of the Infinity 2000A's on top and cut its woofer out. Not perfect, since the number of panels is unbalanced and dispersion is twisted-- but there's timbre-matching and both have front and back open cutouts.

So... to add to the natural sounding low bass module's 'top dog' we have here the >7500 Hz 'top dog' too. They deliver what the 2000A promises to deliver.

Midrange has a pleasing tone. Not pinpoint, not high detail like KEF uniQ or as airy and disappear like the DQ-20's. But they have tone down true. For strings and vocal Jazz.

This is not easy.

And they form a good team with the other modules as a system. So bebop. So they probably are rolled off exactly where they should and at the right slope, so again, improving on Robert Fulton's obsession may just mean...new caps...to restore them to how they sounded in the 70s?


The mid drivers are well balanced in the setup. I do think if I pulled the 4 peerless tweets out of the loop and set more Estat panels and crossed lower, it could be better. Or not.


Or if I placed the Bozak B-301F's in as the middle module, it would be better. Or not.


I just allowed a little more power... and they just get better with higher wattage... better let off the gas a bit til a thorough total refurb, these are not Altecs okay?:nono::nono:

 

[SpeakerLabFan]

Til I can fix one of the tweeter modules

I placed one of the Infinity 2000A's on top and cut its woofer out. Not perfect, since the number of panels is unbalanced and dispersion is twisted-- but there's timbre-matching and both have front and back open cutouts.

I just allowed a little more power... and they just get better with higher wattage...

better let off the gas a bit til a thorough total refurb, these are not Altecs okay?:nono::nono:

Thanks for the reports and good luck with the fixing /tweaking! What do you think is involved in fixing up the tweeter module? ...do you know if the issue is with the crossover electronics or with the estat panels?

What amp are you using to drive them?

 

[Susurus]

For sure it's the electronics. That's a very good thing!

Seem to have narrowed it down some, great to have the working one as a template to crawl around there with the ol' Fluke DMM.

Could just be the circuit breaker or the big spark gap. The pots do need a date with Caig's. .. :yes: Already found one resistor that had detached a lead. :thmbsp:

Soldering shows signs of a quick and dirty redo. Or two. So that's another idea.

At the moment, SX-1250 on FM. They will get fed others soon; certainly the C-4's multi pre-outs for 'cheater's' bi-amping.

And vinyl will get a turn (pun intended). Take a Pebble, from your gift ELP (You rock, seriously--it's not opinion--it's a fact), when I'm sure the cart is aligned right.

 

[Susurus]

I will post pics of inside the bass cabinet, where the 3 boards are located.

These officially hold the record for Worst WAF Factor ever, not looks but the overhang of the top module is a hazard. They are supposed to go into a dedicated audio room, inner sanctum, cave, to be an alter for the lesser luminaries to stand Easter Island-like in frozen awe. Or was that me?

 

[SpeakerLabFan]

They are supposed to go into a dedicated audio room, inner sanctum, cave, to be an alter for the lesser luminaries to stand Easter Island-like in frozen awe. Or was that me?

:yes::lmao:

 

[dokblues]

Very very cool I remember reading an article way back in the 70`s about them but I have never heard them, that would obvoiusly be a real treat! Kudos SpeakerLabFan and kfa888 for all the Karma in this deal!! All I can say is WOW!! :thmbsp:

 

[Susurus]

That SP article is on-line here.

Well it's official. I like these better than any other here in the Land of Misfit Speakers.

First fool's bi-amp was all toroid (Second will be all-E-transformers; M-4 with the Concept, then maybe a Tri-amp with a Luxman stack).

Did have to track down the source of polarity problems:

1) worn-off label on my DMM probes.

2) Fulton's mislabeling the terminals in the midrange box. Maybe got caught up in the craze for switching mids polarity for showroom 'sizzle'.

3) One channel on my SAE amp has terminals reversed inside! :screwy::thumbsdn:

4) Pioneer reversed ALL speaker terminals on my 1250. Red is negative. Good grief. Guess they didn't imagine 30 years later I was going to biamp with it, and needed a little consistency.

5) Mislabled speaker wires. Oops.

That's a high enough rate of screwyness that I'm gonna check my other gear. Suggest it isn't limited to my SAE, Fultons, old HPM-100's and Pioneer receiver. Who else has found stock wrong polarities?

===

The good thing is, even with so many twists that the outcome polarity was more or less random, the AA battery trick and DMM on the terminals cleared it all up.

Another try: DMM on the speaker terminals, gently push the woofer cone--if it reads a Negative swing, it's wired correctly.

Result of all this was: Fool's biamping originally made it sound deranged.

But now it's a different sound. Clearer, better low bass (SAE has a high DF (500?) compared with the 1250 (30)). More ability to handle multiple complex fast percussion. Yes it's crossed over low at 83Hz but it's a gradual 6dB slope; lots of overtones come from it.

Problem is that crappy sources are more in your face. Great sources, like the live classical FM broadcast (on a low-signal-processing station), go from great to "I've fallen into my Listening Recliner, and I Can't Drag Myself Away".

So far I still haven't given it a dose of vinyl yet. (An AK'er with a hefty Karma surplus already has offered to help me fix the transport belt on the PL-10 linear TT. :thmbsp

 

[Susurus]

Respite from the cold, snow, and ice...update on the FultonJ project.

So far the best midrange setup comes from using the C-4/Hafler. :yes:

The Fulton-80 mid module is wired with the twin square Peerless tweeters in phase with the other modules, but the midbass 6" polarity reversed. (Both sides are like this so it seems intentional). This is an acoustic suspension cab, small volume like an AR-4ax but I can only theorize from reading that its tone sounds closer to an Allison or Cizek.

Can't see why Stereophile Mag compared it with the Dynaco 25 since that one is ported. Well maybe because early versions of it used a Peerless midbass like the 25s (mine seems to be a later CTS, reportedly goes lower. Peerless has been following me around a lot lately; ESS-9, DQ sub--don't have that yet just reading about it).

Bass cab was designed from the ground up for bass <83 Hz. I have nothing to compare it against presently. My exposure to enclosed cab powered subs is limited to Klipsch HT towers I no longer have. Its 10" driver tended toward the 1-note but had slam for LFE.

Slam is not the point of the Fulton FMI-E LF module. It is more of a balanced compromise that's musical in the first degree, and it's low enough, dynamic enough, and produces SPL enough to show where most full-range E-stats trip. It's not as placement sensitive as ported single subs or OB/Limited B. Would like to measure it to see how close it comes to orig specs but I don't have a mike.

The woofer driver is mounted very high up close to the mids. Hope R.Fulton took into account the spacing from the drivers there. Only thing I have with high mounted woofers this close to the mids is my DQ-20i. Lots of people like that one... Seems more modern designers are more concerned about the cost and worry of a heavy enough cab having a topheavy position...it would cost more and would worry about toppling over.

Well the Fultons' detached modules are just so impractical anyway outside a dedicated, no-kids-no-animals-no-busybodies listening room that it just don't matter. :nutz: It's supposed to be all about the music... when did they lose sight of that?

I've had time to delve into a newer version of the Infinity 2000A with replaced, remade or redesigned guts. Word is these broke down a lot when new so I'm not surprised at the differences: instead of the spark gap there's a whole lot more caps in there and a different trans. It never hums, hooray!

So I've got something for each side that'll drive the E-stats. Likely with a detachable separate setup. Soon I'll get to hear something closer to what these were supposed to sound like.

With the 4-panel 2000A's placed on top, I think for the first time I can tell differences between my 4 cheap CDPs.

Still have to deal with the different crossover nodes between the FMI-6 and the 2000A. 5K and 7K but don't quote me.

 

[Susurus]

Each of the 3 modules are good enough to stand on their own.

Reminds me of certain groups; The Police, ELP, Rush. Can be harder to integrate solo-level artists into a cohesive package--inherently unstable but worth the effort when it truly clicks.

:guitar::sing:

So many systems seem more like The Monkeys. They were a parody, or a completely artificial TV construct. 2 credible musicians, an actor, and an actor who could sing (or vice versa?).

:scratch2:

 

[Brian Beck]

Model type clarification

Just to clarify - because there seems to be recurring confusion about the model number here. The speakers shown at the top of this thread are not the J-Modulars, but the E-Modulars. The difference was only in the bass cabinet, the E-Modular being the smaller and less costly variant. But the upper two boxes on each side, the FMI-80 and the FMI-6 (really just tweaked RTR ESR-6 speakers as some surmised) are the same in the J-Modular and E-Modular. In many variants, the FMI-80s ran without a crossover roll-off (low-pass) on the highs. The ESR-6 output was added to the gently rolling-off responses of those two Peerless Alnico paper cones (marvelous drivers, much better than you'd think). The bigger J-Modular used two bass drivers per side, a 10-inch forward firing woofer and a 12-inch slot loaded driver facing the floor, sharing the same internal air volume. The crossover was prodigious, and made use of several starter solenoid coils from autos as inductors. The bass cabinet was about 2' on a side and dwarfed the boxes on top. A fabric shroud of the same dimensions was placed over the upper two boxes which made the J-Modular look far more finished, if you like big black refrigerator-sized boxes in your living room. I heard the J-Modular extensively during its heyday driven by vintage Audio Research tube gear. It thundered and roared but with great delicacy and detail. The midrange was uncolored and the highs were airy and sweet. Paper drivers with Alnico magnets plus those ESLs made for a great sound. Human voices sounded especially natural through them. I owned yet another variation: the FMI-100s plus those same FMI-6 electrostats. The FMI-100s used four of the Peerless cone tweeters and a larger 10" woofer, so they could go deeper than the FMI-80. No subwoofer was used. Wish I hadn't sold them years ago. Currently I have a pair of mint FMI-80s for my office system. Lovely, articulate little speakers. Thanks for the trip down Memory Lane.

 

[kfa888]

Great info thanks.

two Peerless Alnico paper cones (marvelous drivers, much better than you'd think)

I know I am hording small piles of them.

 

[Susurus]

Weird crossover. Auto parts inside!

And the RCA jacks are not the same as the screw terminals. The terminal wiring is sort of hidden inside some hard plaster; that's not clay.

Without the info sheet SpeakerLabFan kindly included, I'd have assumed--wrongly--while putting on 5way post terminals. The bi-amp setup means using the upper RCA as Mid/Tweet inputs and the screws as outputs.

 

[Susurus]

Big honking 3" VC alnicos.

Housing for motor is 4" x 6", spider is 6" wide for long throw. Surround seems treated pleated.

What I'd expect for an Acoustic Suspension dedicted LF cab that's crossed over at 83Hz.

I can't find any writing on it. Who made these? Tried to get some of the fiberglass dust off too. Maybe it's car parts too like the Xover inductors.

 

[Susurus]

Just to clarify - because there seems to be recurring confusion about the model number here. The speakers shown at the top of this thread are not the J-Modulars, but the E-Modulars. The difference was only in the bass cabinet, the E-Modular being the smaller and less costly variant.

Guess I'll need to construct something J-clone-like then, to correct my error. Or just because.

But the upper two boxes on each side, the FMI-80 and the FMI-6 (really just tweaked RTR ESR-6 speakers as some surmised) are the same in the J-Modular and E-Modular. In many variants, the FMI-80s ran without a crossover roll-off (low-pass) on the highs.

I've tried it both ways now and figure (my fakey) bi-amping shows more of a difference than crossover vs. 'air' roll-off. Still gotta try active though.

The ESR-6 output was added to the gently rolling-off responses of those two Peerless Alnico paper cones (marvelous drivers, much better than you'd think).

Well I now have them in ESS-9's and my one orphan (singleton looking for its Valentine) Sonab CA-14 R. The Fultons' have some kind of fuzzy coating or debris on them.

The bigger J-Modular used two bass drivers per side, a 10-inch forward firing woofer and a 12-inch slot loaded driver facing the floor, sharing the same internal air volume. The crossover was prodigious, and made use of several starter solenoid coils from autos as inductors.

This here is so weird I found it necessary to show the pic. My 'E' shows 4 of these in series. And silver caps... maybe automotive too?

[...] I heard the J-Modular extensively during its heyday driven by vintage Audio Research tube gear. It thundered and roared but with great delicacy and detail. The midrange was uncolored and the highs were airy and sweet. Paper drivers with Alnico magnets plus those ESLs made for a great sound. Human voices sounded especially natural through them.

That characteristic alone, yeah. Natural. Realistic. No wait...

Currently I have a pair of mint FMI-80s for my office system. Lovely, articulate little speakers. Thanks for the trip down Memory Lane.

Seems in mine the mids were wired out of phase with the woofs and tweets. That may have been intentional or not, but BobF seems to've been fastidious, to the point of specifying differences in the precise offset distance for stacking the 2 mid module choices. If I experiment with larger DIY cabs with my set of Speakerlab 3 drivers, I'll have to try both ways.

 

[Susurus]

'nother pic.

The Mid module 6" seems to have a permiable dust cover. hmmm! I'd thought it was Acoustic Suspension! What do I call this cab? I thought my DQ-20's were odd, with the bass-reflex midrange.

The tweets there have some kind of fuzzy coating or debris on them. I'm sure if it was intentionaly applied, BobF would have taken the mass change into account.

 

[SpeakerLabFan]

Enjoying the pictures, and discussion. Hey if you ever need a solenoid coil for temporary service in the car, you know where to borrow one. :tresbon: