Real TrainWreck mojo!

[Chuck H]

I want to discuss something that feels like it may be both above and simultaneously below my pay grade as a forum poster here... The TrainWreck amps and their secret tonal mojo.

I know that many posters here are ready to poo poo the idea that any such mojo exists. I disagree. Some chalk it up to a happy accident. I disagree with that too. Please let me explain...

Real Ken Fischer made Express and Liverpool amps seem to possess two qualities that are notably lacking in any clone attempts. One is that they consistently have a defining "chip" on the attack of even the lowest notes which is great for fast lead picking. Yet they aren't overly stringent on the attack of higher register notes. The other is that they all swirl so beautifully. The bloom and swell of the notes, again both lower and upper register, has no ugly fizz or buzz. It's more like a touch wha that's far better than any pedal. All of the KF built amps do these things and few of the clones do. And none of the clones that do can do it as well as the recorded examples of KF built amps. So...

Say what you will about Ken and his occasionally questionable statements, quotes or misquotes. The guy was on to something. Whether he didn't reveal or explain it or whether he couldn't is irrelevant at this point for obvious reasons. The guy consistently built amps that out performed the copies and clones to this day in these two elusive tonal properties. So he was obviously privy to something that is repeatable, but no one since his demise has been able to repeat. And I, for one, would love to get to the bottom of it.

There has been some speculation on some of it. Steve Conner suggested that it probably has to do with his some time quoted design ideal of finding the edge of stability. That doesn't get us very far without some experiments and bench test results. I personally have never built a TW clone so I can't offer any reports on personal experience. I'm hoping someone can or that the sheer level of experience and knowledge on this forum can shed some light on what to examine at all.

I want to say now that if you're inclined to post for not much better reason that to say it's all BS, please don't bother. I know there are plenty of folks that feel that way. I don't care if you do too. It's not personal though. I still like all you guys and I'm usually happy for a diverse perspective. I just don't want this to instantly become a discussion I didn't intend (though I know it will eventually )

The guys at Amp Garage will be eternally grateful if we can make headway on this. Not that it matters much, but we DO have seniority

[g1]

The one idea I've seen speculated is pretty tough to refute (or prove I guess), that is using lead dress as "invisible" capacitors.

[daz]

So Chuck, If i read you correctly it seems what you said is that you can build and exact clone, but component tolerances they will always like any amp clone or even 2 stock identical say marshalls will be slightly different. And that Ken knew that there was some important area in the amp that must be fine tuned to perfection by using components that are always an exact value. Is that what you mean? What about transformers? Is it possible to get the exact ones he used? Because if he had them wound to his spec maybe thats why the clones cannot recreate it ?

I think that whatever it is it just might have to do with the gain structure at each stage to get the perfect balance so each stage overloads to some exact amount he come to understand would get what he was after. because isn't the magic with those amps all about the non MV cranked sound? Getting just the right amount of drive from each stage that gets the magic maybe. Because unless i'm mistaken, the guys that clone them seem to suggest that with a MV or just using them clean doesn't give the magic. It's only when cranked.

[loudthud]

I had a Traynor YBA-1 with a Triad 6.6K output transformer that I converted to the Express circuit. It took a lot of futzing around to get it to stop oscillating. Most of that was due to the non ideal layout. I ended up building three shields. The clipping at the input is something around 100 microvolts. None of the guitars I have will allow the volume to be turned up past 12:00.

Reading on the Amp Garage forum I was intrigued with the power scaling since the B+ was on the high side with the stock Traynor power transformer. Just to make things easy I just patched in a 6.3V filament transformer and used a variac to change B+. It actually does a reasonable job down to half line voltage, about one quarter power.

The screen supply sags alot. You really do need that 25W 1K resistor. Despite this, the gain doesn't compress any more than a 5E3, about 3dB IIRC. I would like to come up with a different way to look at the attack profile and compression of an amp.

[Chuck H]

Most of the KF amps are reported to be a little finicky in some ways. The sweet spot for the controls seems to be 5, +/- 1. Most are said to oscillate when pushed too far on the volume and/or treble. I don't know that they left the bench like this but I've read this is reported by many TW owners.

I don't think it's the transformer per se, though the relatively high primary impedance probably has something to do with it. Glen Kuykendall has a Pacific OT wreck. Because of his unique status as the patron saint of recorded TW samples he's been able to audition many other TW amps. Some with the Stancor OT. apparently they all do the right things. The Pacific loaded amps are more "aggressive".?.

Some amps used a shield to the second gain stage. Some amps had a 1.5k resistor on the grid of the second stage. Some of the Liverpool amps used a different load resistor between stage two and three. These are variables that may be found on any KF TW Liverpool or Express. Some other differences have been reported but not documented and I've never seen evidence to support them.

I'm inclined to agree that lead dress had to be the secret "voicing" since all the amps use the same parts. I also think that the particulars of the power supply, especially the use of a 1k resistor instead of a choke, is part of the overall formula. But exact clones have been made from reverse engineered examples with only limited success!?! Reports of amps serviced by Ken are that they were returned to all their former glory. While I've heard KF amps that were serviced elsewhere after long periods of MIA that never again sounded any better than the many clones. So what the hell was Ken doing to these amps that made the pick attack go crunch and the sustain go bwaaah. Rather than a spikey thwack and fwizzz like the copies. Glen Kuykendall built himself a couple of clones with every part NOS and TW OEM except the Mallory filter caps. And his findings were that the filter caps made a huge difference in getting closer to the sound of his original. This also corresponds with the idea that unwired circuits are partly responsible because the filters he ended up with were some boutique product that was supposed to be like the older caps!?! I might interpret that as higher impedance (or ESR, if that's actually different). So now we have unseen circuits hiding in the lead dress AND NFB and possibly PFB loops hiding on the power rail. But I've never seen a TW that left his care with anything but the original filters inside. So that only leaves lead dress.

I just can't help but think that if we could know WHAT he was doing to voice these amps and how they were affected, which probably had to do with lead dress as speculated, then the most stable lead dress could be used and the affect could be implemented with actual components instead. Thereby making it possible and repeatable for cloners and copiers to get that "right" tone. I don't want to get called out for using the term "golden ears" but why hasn't some fairly intuitive builder moved their Express clones leads around until the magic came out? I honestly thought that was eminent by now. But it hasn't happened so I started this thread.

[daz]

Well, what WERE the trannys he used? Has anyone built a clone using the same ones he did or is that impossible because they don't make them anymore or they were custom wound or whatever? I find the lead dress thing kinda unlikely just because with 8 trillion clones out there i would thing just random chance would have a fair portion of them coming out "right", especially if gut shots are available to those making the clones. On the other hand, something like a component brand thats no longer available seems more likely. Lastly, how many clones really try and be exact? I aks because i have a TW PDF that someone made showing about 10 variants, so it makes me wonder if most people change them to some degree to try and improve them since they don't seem to bve able to just fire them up and get satisfaction. So it may be most build slight variants.

Most of the KF amps are reported to be a little finicky in some ways. The sweet spot for the controls seems to be 5, +/- 1. Most are said to oscillate when pushed too far on the volume and/or treble. I don't know that they left the bench like this but I've read this is reported by many TW owners.

I don't think it's the transformer per se, though the relatively high primary impedance probably has something to do with it. Glen Kuykendall has a Pacific OT wreck. Because of his unique status as the patron saint of recorded TW samples he's been able to audition many other TW amps. Some with the Stancor OT. apparently they all do the right things. The Pacific loaded amps are more "aggressive".?.

Some amps used a shield to the second gain stage. Some amps had a 1.5k resistor on the grid of the second stage. Some of the Liverpool amps used a different load resistor between stage two and three. These are variables that may be found on any KF TW Liverpool or Express. Some other differences have been reported but not documented and I've never seen evidence to support them.

I'm inclined to agree that lead dress had to be the secret "voicing" since all the amps use the same parts. I also think that the particulars of the power supply, especially the use of a 1k resistor instead of a choke, is part of the overall formula. But exact clones have been made from reverse engineered examples with only limited success!?! Reports of amps serviced by Ken are that they were returned to all their former glory. While I've heard KF amps that were serviced elsewhere after long periods of MIA that never again sounded any better than the many clones. So what the hell was Ken doing to these amps that made the pick attack go crunch and the sustain go bwaaah. Rather than a spikey thwack and fwizzz like the copies. Glen Kuykendall built himself a couple of clones with every part NOS and TW OEM except the Mallory filter caps. And his findings were that the filter caps made a huge difference in getting closer to the sound of his original. This also corresponds with the idea that unwired circuits are partly responsible because the filters he ended up with were some boutique product that was supposed to be like the older caps!?! I might interpret that as higher impedance (or ESR, if that's actually different). So now we have unseen circuits hiding in the lead dress AND NFB and possibly PFB loops hiding on the power rail. But I've never seen a TW that left his care with anything but the original filters inside. So that only leaves lead dress.

I just can't help but think that if we could know WHAT he was doing to voice these amps and how they were affected, which probably had to do with lead dress as speculated, then the most stable lead dress could be used and the affect could be implemented with actual components instead. Thereby making it possible and repeatable for cloners and copiers to get that "right" tone. I don't want to get called out for using the term "golden ears" but why hasn't some fairly intuitive builder moved their Express clones leads around until the magic came out? I honestly thought that was eminent by now. But it hasn't happened so I started this thread.

[Chuck H]

The transformers are well known. Many clones have been built with them. And I agree with you about the 8 trillion clones. Put an infinite number of monkeys with guitars in a room and one of them will play Proud Mary! Right? No offence with the monkey analogy guys Yet the fact remains that any TW leaving Kens bench sounded right and as far as I've been able to tell none of the clones and copies ever reach that level. Some sound harsh and even bad. Some just fine, but somewhat more average. What accounts for that last ten percent of relative goodness.

The lead dress issue has to be where it is. All things aren't created equal. Individual component and tube variance change the inductive relationship WRT the invisible couplings. So a wire run in the exact same place in two amps isn't doing the exact same thing. It's possible that there are, say, three leads accidentally or strategically located in the Express layout that, when manipulated, can change it's character from bland to harsh to magic with only minor changes in routing or length. The goal of this thread would be to determine if this or some other element may be responsible for the secret "voicing" technique used by Ken. A technique he is said to have attempted to teach to others unsuccessfully though no one has ever come forward with any information about it. Probably because it seemed ridiculous to most sane amp techs and it would be embarrassing to admit that you couldn't do it once shown.

Ken was also said to swap certain components out within their value tolerance. Let's assume a 10% tolerance.?. So a 100k resistor in one of his amps could be 90k or 110k, but most likely somewhere in between. It's also said that he would take more time swapping components and "voicing" the amps than the time it took to build them. Apparently Glen Kuykendall's amp never sounded quite right and Ken gave up on it. Somehow it ended up in a guitar shop where Glen found it and bought it. That's how it got the name Orphan Annie. This tale lends some weak credence to the notion that there was some measure of effort put into the final voicing of the amps. And since they all have, on the macro view, the same component values and layout, what was being done to voice and adjust them?

I've clearly put too much in thinking about it. It intrigues me because it's weird and fly's in the face of standard practices.

[daz]

Thats what i was suggesting in a post above, RE: component tolerances. Seems like maybe the only other notable variable along with lead dress.

On a side note, TW amps don't hold any real interest to me personally because even when i gigged regularly e were never able to turn loud enough for an amp like that. Maybe at a opriginal style gig, but cover gigs were too low volume to make use of a amp who's magic could only be had cranking it. That was my whole reason for building what i did....to make a marshall that had the qualities i like at a lower volume. Guess i coulda used an attenuator, but i just never thought the one i used sounded very good and that made me a bit gun shy of them.

The transformers are well known. Many clones have been built with them. And I agree with you about the 8 trillion clones. Put an infinite number of monkeys with guitars in a room and one of them will play Proud Mary! Right? No offence with the monkey analogy guys Yet the fact remains that any TW leaving Kens bench sounded right and as far as I've been able to tell none of the clones and copies ever reach that level. Some sound harsh and even bad. Some just fine, but somewhat more average. What accounts for that last ten percent of relative goodness.

The lead dress issue has to be where it is. All things aren't created equal. Individual component and tube variance change the inductive relationship WRT the invisible couplings. So a wire run in the exact same place in two amps isn't doing the exact same thing. It's possible that there are, say, three leads accidentally or strategically located in the Express layout that, when manipulated, can change it's character from bland to harsh to magic with only minor changes in routing or length. The goal of this thread would be to determine if this or some other element may be responsible for the secret "voicing" technique used by Ken. A technique he is said to have attempted to teach to others unsuccessfully though no one has ever come forward with any information about it. Probably because it seemed ridiculous to most sane amp techs and it would be embarrassing to admit that you couldn't do it once shown.

Ken was also said to swap certain components out within their value tolerance. Let's assume a 10% tolerance.?. So a 100k resistor in one of his amps could be 90k or 110k, but most likely somewhere in between. It's also said that he would take more time swapping components and "voicing" the amps than the time it took to build them. Apparently Glen Kuykendall's amp never sounded quite right and Ken gave up on it. Somehow it ended up in a guitar shop where Glen found it and bought it. That's how it got the name Orphan Annie. This tale lends some weak credence to the notion that there was some measure of effort put into the final voicing of the amps. And since they all have, on the macro view, the same component values and layout, what was being done to voice and adjust them?

I've clearly put too much in thinking about it. It intrigues me because it's weird and fly's in the face of standard practices.

[big_teee]

I've looked at a lot of the schematics.
Steve A has a lot of them on his blue guitar site.
What I noticed, is best I remember he never used any Chokes.
Always kept the B+ voltage low, which usually gives the preamp more grit and bite.
And He didn't usually use a CF in his amps.
Maybe you have to tune the B+ rails for that optimum Wreck Sound.
T

[jazbo8]

It could just be that KF has better ears and more experience with amp tuning, I doubt there is a definitive technical reason to be found, otherwise, some smart cloners would have figure it out... I bet someone has already tried to duplicate the 3D wiring in the Wrecks down to the millimeter, yet still no cigar. If we are talking about wire routing (or even the sleeve color and composition of the wires), then it is down to parasitic capacitance effect, even if that's the case, is that a reliable way to design or work on amps?!

[daz]

I've looked at a lot of the schematics.
Steve A has a lot of them on his blue guitar site.
What I noticed, is best I remember he never used any Chokes.
Always kept the B+ voltage low, which usually gives the preamp more grit and bite.
And He didn't usually use a CF in his amps.
Maybe you have to tune the B+ rails for that optimum Wreck Sound.
T

Those are a big part of the sound as all the other circuit details no doubt, but Chuck's point is that things like that can and are easily recreated by hoards of cloners without getting the magic result. He's looking for the inconspicuous thing that seperates the real thing from a clone.

Chuck, can i assume people have scoped the real thing out to try and replicated the same results in a clone?

[big_teee]

Those are a big part of the sound as all the other circuit details no doubt, but Chuck's point is that things like that can and are easily recreated by hoards of cloners without getting the magic result. He's looking for the inconspicuous thing that seperates the real thing from a clone.

Chuck, can i assume people have scoped the real thing out to try and replicated the same results in a clone?

Trainwrecks are like PAFs, a lot of us have only seen and heard them on recordings and the Internet!
This Sounds similar to chasing the elusive Slash Magical Marshall of old.
GL,
T

[Chuck H]

Chuck, can i assume people have scoped the real thing out to try and replicated the same results in a clone?

I wish! The unfortunate reality is along the lines of what BT said. There were an estimated 100 amps made by Ken. This is all inclusive between the Express, Rocket, Liverpool and a few oddities that were one offs. With the clout they carry most are either sitting idle with non tech collectors or well healed players or waiting to be sold by to such by one of the big vintage specialty shops. Once in a while you'll hear about a famous player acquiring one. I know that a couple reside in famous recording studios. The bottom line is that anyone with the money and desire to own one of these amps would not be interested in, nor benefitted by a bunch of bench test results.

They sure make a big noise for such a small showing!!! Brad Paisley owns one now. You can tell when he's using it because it sounds like crap! Definitely not an amp that had seen Ken's touch in a long while. And Brad, of course, has an amp tech. Who probably got it up and running in top form... Minus the special sauce!?!

[Chuck H]

This Sounds similar to chasing the elusive Slash Magical Marshall of old.

Except that in the case of the TW amps there was a guy who could make more "magical" amps. Proving that the magic was repeatable! Not just one special individual accident.

[Chuck H]

It could just be that KF has better ears and more experience with amp tuning, I doubt there is a definitive technical reason to be found, otherwise, some smart cloners would have figure it out... I bet someone has already tried to duplicate the 3D wiring in the Wrecks down to the millimeter, yet still no cigar. If we are talking about wire routing (or even the sleeve color and composition of the wires), then it is down to parasitic capacitance effect, even if that's the case, is that a reliable way to design or work on amps?!

Well, now, that's what daz and I have been kicking back and forth. All the blue printed examples have the same components (within tolerance) and only minor differences in lead dress. And even though manipulation via finite component value and minor lead dress changes may not seem like a reliable way to build or work on amps it's possible that there was at least one guy that could do it. I'm not inclined to poo poo what's on the table if I don't have a more plausible alternative to offer. I just want to know what he might have been doing. And hopefully find out what the net effect was. It would be nice to have a target and parameters to aim for when trying to get such properties in other amps too! Some rare old Marshalls have been known to have these properties. It's assumed that since it's rare it's an accidental result of extreme mass production. Ken was distinctly NOT mass production and made MOST of his amps do it! I want to know how.