Voicing a trainwreck

[M Fowler]

No I am never going to knock HAD either. He did things his way and took no crap from anyone, not to mention the great amps, cabinet designs/ other things he built.

[CaseyJones]

I think the biggest thing that separated Ken from HAD was Ken didn't charge $200/ hr for a phone call........

Bet you'd give $200 and your left nut for a chance to talk to Alex.

[selloutrr]

Not old lefty!

[Cliff Schecht]

This thread went downhill quickly .

[muchxs]

This thread went downhill quickly .

That's Navy electronics training. "Dive, dive!!"

[selloutrr]

it's cool at least it went some where lol

[KeithStevens]

I was never lucky enough to meet or talk to the man...but from what I've read, I think he voiced his amps by doing the one thing that most humans just don't seem to have any ability or interest in...he LISTENED...

I was at his house on a couple of occasions. He blew my mind. Really. And you're right, he had the ability to really listen. He listened when you talked to him and he listened critically when you played his amps. He played some LP tracks on a stereo tube amp he worked on for us to listen to. The man was just devoted to sound. So sad he's gone.

[Structo]

I think the biggest thing that separated Ken from HAD was Ken didn't charge $200/ hr for a phone call........

Bet you'd give $200 and your left nut for a chance to talk to Alex.

No my wife would never forgive me. (about the left nut that is)

It would be interesting though to be a fly on the wall.

[redshark]

I brought this thread back because we were discussing how to bias the express amp but that is a part of the bigger picture which is voicing the amp. Something that nowadays is I believe the missing link between a clone and a real trainwreck amp.
For some people this is an urban legend but if we go back to 2005-2006 when the Francesca pics came out there you can go to threads and read the whole drama between the guys that were Ken's friends that were pretty upset about posting those pics. Instantly people started adjusting the lead dress to the pics and most of the people reported tone improvement about moving wires. I tried that myself and in 4 months I noticed tone diferences by moving the wires. It got warmer, brighter, gainier, sometimes microphonics became more aparent and then moved some wires and certain rattles went away.
Recently with the TW reissues something was written about some misterious 5 laws and I think that the emissions generated by wire positioning (lead dress) alter the tone and response. If this little changes could be proved and controlled using a scientific approach then it could be stablished as a law.
Is sad that Ken had to protect all this knowledge for people trying to profit from his work.
So lead dress under control, bias using ears, selection of preamp tubes, maybe a couple values tweaked is all parts of the big recipe....
The people that were upset about the pics they said by giving that away you were giving also the work of "countless hours" that Ken spent moving wires....Does that tell you something????

[M Fowler]

I think several things happened to your amp in 4 months time, number one the amp settled in (the components such as caps) and the fact that you addressed the lead dress issues.

Both are critical for a great sounding amp no matter which type of amp.

[paulster]

The Express circuit is very prone to parasitic oscillations given the gain levels, the lack of inter-stage attenuation, the lack of shielded cable and the lack of grid stoppers.

I had a weird one the other week affecting both an Express and Liverpool that turned out to be a 588kHz parasitic that wasn't making it as far as the power tubes so didn't exhibit any problems unless you had the treble control on full with the volume at about 1 o'clock (highest impedance source) at which point it caused power supply modulation.

That turned out to be the damping I'd put on the chassis lifting the 2nd stage grid wire off the chassis just that couple of millimetres too much to get a good shielding effect.

So the skill with these things isn't really voicing them by moving wires, it's more about getting them to the point where they're properly stable, but also properly stable without having phase shifted wires close enough that you end up introducing unwanted local negative feedback and killing the bloom factor. IMO of course!

[redshark]

Paulster by properly stable you mean that the amp sounds great at normal playing settings with a guitar plugged in?
As I mentioned before in my amp once the cable is unplugged and the treble and presence maxed if I turn the volume up exactly around 1-2pm the amp squeals then passing that just the hiss and noise gets bigger.
I moved wires and I was thinking to get rid of the problem but then I though...the amp was meant to be played and at the settings that are the most common for the amp to provide the best range which is volume at 1pm and all other knobs flat (12noon) the amp sounds amazing....so why bother? at those settings my hiss is low so that doesn't even bother me and the hum (P-90 pickup) is not very aparent. Somebody mentioned that the oscillation with cable unplugged at those settings could be a microphonic and noisy V1 or V2 tubes and I have to admit that the ecc83 old mullards that I have in there were not tested for noise or microphonics so I guess that to get pre-screened tubes for V1 and V2 is a first step.