kevin gilmore

RE: pics Unless there was a significant amount of drugs involved (like gallons of booze) there is no way in hell the same person built both parts of the amplifier. That or mikhail has multiple personalities.

current best guess updated after becoming one with the pictures Scared to hell i am... unplug umbilical to amp, leave gas tubes out of the socket, and accidentally turn it on. More than 1kv with enough energy to throw you across the room sitting on those gas tube sockets... I still think that is a 6m... not an 8m... Doesn't matter.

current best guess http://gilmore.chem.northwestern.edu/sdsgasps.jpg getting pretty close... there have to be a few hidden diodes... for the ignition circuit to work.

the diode bridge sure looks like gbu6m (fairchild) and is rated for 1000 volts... Trouble is it is running at 1100 volts...

Lets start with the pass fet. It is under rated for at least 50 volts. Likely it and the diode feeding it are toast. There is only one fet right?? here is a much better part that i have not been able to kill yet with extreme abuse. http://ixdev.ixys.com/DataSheet/DS99843B(IXFH-T20N100P).pdf Direct replacement. I'm worried about the diode bridge attached to the center of the chassis also not being rated for voltage. Hard to figure out the part number with the chassis nut in the middle, but will try and find it. Back shot of the circuit board would be VERY HELPFUL. Was that fet even bolted to the chassis, and was there any thermal grease?? Because at the power that was running at... If you have trouble uploading the pictures email them to me and i will put them where everyone can see them.

Just think how much the insurance companies that were insuring that 3 year tour will be shelling out on this. And the millions of pounds of ticket sales in the UK... He really was extremely talented. Too bad the head was so fucked up.

I want really good pictures of the insides of the amp. Reason is i want to see how the high voltage is wired. Need to know how it is split. Absolutely there is A FET on the back of the large PCB. You are going to need to flip out that side of the chassis. And take some straight on pictures of that board, and underneith it. Please get a better camera Like a Nikon D3X... Better yet, the new mamiya with the 32mp back...

That is a different kind of thing as the board in the cd player is dc coupled. But i'm now thinking that a quick (quick??) replacement of the FET and the diode that feeds it might get you running again pretty quick, and once you take it apart enough to figure out what the part number of the fet is, someone local could probably fix it pretty fast.

Just saw pictures of neil's amp. Pretty pissed at the moment. Which leads to the following politically incorrect comment... (with a russian accent) "IT MUST BE BUILT LIKE SHIT TO SOUND GOOD" The amount of total clusterfuck here is awsome.

I like the display!! got all the parts from marc. Now i got no time... As i'm doing lots of Singlepower Midwest support

And now we know why the filament transformer looks a bit crispy. Some of those tube combo's especially 6bl7's as the output tubes gets the filament current in the 6.6 to 7.5 ampere range.

Yep the 2 x 5u4's are in parallel and the second transformer does nothing except make 1100 volts likely used as the gas tube starting voltage. and there really is only one fet... so the left channel, right channel seperated power supplies is pure gold plated texas cow dung.

Well the power supply is 2 x 5u4 and 6 x gas tubes plus 3 transformers and a pile of extra shit. The amp is balanced and is therefore 6 tubes, the usual mikhail plug in anything you want with adapters, but standard is 6 x 6sn7. 1 dual triode gain tube per channel, 2 dual triode output tubes per channel in WCF. So in picture dscn2645 is the semiconductor mounted to the chassis 4 wires or 3 wires... Sure looks like 4 wires, and therefore a diode bridge, tied to the second transformer, which makes it interesting because it sure looks like the 2 x 5u4's are actually in parallel which also makes absolutely no sense...

Build one! Schematics available.

Shame on you nate... Go and look at the schematic i posted on this. The filament windings on the 5u4's are firstly 5 volts, and second, they are lifted up by about 500 volts. Those filament windings are part of the 278x transformers. One transformer per 5u4. OK, so voltron, you got the thing apart, lets go a little further, take the screws that hold the posts on, and tilt out the main circuit board, leaving it attached to the aluminum and take straight on pictures, and pictures under the board... What i'm now thinking is that mikhail lied about how the thing works... (no never would he do such a thing.) There may in fact be only one fet. So one of the gas tube strings is used as is without a buffer and just runs the 2 input tubes. and the other gas tube string is used with the fet buffer and runs the 4 x WCF tubes... So the 2 x neutrik power connectors are according to the pdf used to seperate things for maximum stereo imaging ?? Yeah that's it...

The hammond 266n12 is turning into a crispy critter too, just like the one in the extreme... And there is another filament supply on the main board, reason unknown.. Wonder where or if there is a second fet. sort of looks like the 2 tube rectifiers are wired together, and they shouldn't be.

wow, that is something alright... I do notice the 2 solid state diode bridges connected to the heater supply. 4 pins each, mounted to the chassis. This has to be solid state. The 2 x (2 caps in series with resistors) are obviously the main filter caps. Very hard to see, but i think i see at least one fet on the big board to the right next to the orange drop caps. the 3 pins, and it is probably soldered to the backside of the board. Actually labeled on the board as S D G (source drain gate) 2 diodes and 2 resistors in series hooked up to the thing... just stunning work... better pictures of that area of the board would help. edit: where did that second picture come from. Need better photos... DEFINITELY pass FETS... will update schematic in a bit...

Lets try that again just to make sure. There are up to 3 tubes per channel. So if they are 0a3 they are 75 volts each. (red) If they are 0b3 they are 90 volts each. (orange) If they are 0c3 they are 105 volts each. (redish blue) if they are 0d3 they are 150 volts each. (purple) So 2 x 0a3 would be 150 volts... 2 x 0b3 would be 180 volts...

So a number of things are bothering me. Lets look at the main power transformers hammond 278x. Spec is 800 VCT @ 200 ma In a rectifier tube situation, that is 400*1.4 == 560 volts into the main capacitor less the drop of the 5u4, say 20 volts == 540 volts. also according to the 5u4 datasheet the maximum capacitance should be NO MORE than 40uf. Well i see a lot of caps 10 times that big. If you put 2 in series (where are the balancing resistors) that is still 5 times too big. Likely that is what the 4 caps bundled together on the top panel are. 540 volts for an amplifier that should never ever be run at more than 350 tops and a lot of extra power is going somewhere. Furthermore if the gas tubes really are the only regulators, then if you put more than .1uf on the gas tubes they turn into oscillators... Man this has fail all over it. How many people think i'm stupid enough to want to own the repairs to this thing for the rest of my life... Each 5u4 tube should have a minimum of 4 wires going to it, 8 wires right there between chassis and the top. The gas tubes are 4 wires, plus 6 wires to short out the tubes to the switch. Maybe if you remove the switch from the front panel first, there is enough length to pivot the top of the chassis out and over one of the sides. Otherwise how the hell did he put that piece of shit together. Spritzer has kane's es1 now, i'll let him show you the pictures he showed me... More fail... and more lies too, lots of expensive missing parts... What a train wreck. Trying to think of a way to get voltron out of this mess now... Hey voltron, what is your favorite B+ voltage?? 2 gas tubes == 150 volts?? This will influence what i do. On the other hand, i could just send him a pair of bench supplies, one for the high voltage, and another for the filaments... 0 to 300 at 200ma (one of those old heathkit supplies are perfect for this) and 6.3 VDC (one of those ultra cheap chinese things 0-20 @ 6amp) My guess for the umbilicals would be these wires arranged however GND, probably 2 wires, one per amp channel, and possibly one extra for filament ground B+ got to be 2 wires since there are seperated power supplies F+ the other filament wire. If its the ray samuels method, that would be 4 wires, but it sounds like you have 5...

No way i want to work on that thing. If i would work on it, i would own it for the rest of all time. The fact that you can't even open it up shows how fucked up the thing really is. Its a wonder how he even got the thing together, unless the top unsolders with only a couple of wires. Are you sure that only tube sockets and no components are on the top panel? Better pictures any way possible would help me come up with some way to proceed. How many neutrik connectors are there on the back panel? At least with the ES1 units, i know what to do and how to proceed. Got to think about this mess a while. No idea yet what the 4 large caps bolted to the top do...

Completely different kind of thing. If the amp was drawing too much current then the gas tubes would never have enough voltage to light up ever.

here is something that shoud autostart the gas tubes http://gilmore.chem.northwestern.edu/sdsgaspsautostart.jpg

This is mikhail, and anything is possible. But note the big power diodes on the side board. Wonder what they are for since the diode bridge is already mounted to the ES1heater board. I still think that 40ma to run 2 x WCF is pretty minimal, and in any case with the 0d3's is already over spec. Also the fact that the one channel is consistently popping tubes as soon as you put them in, points to much more current than normal. What i was thinking of for the auto-ignite is my stacked high voltage multiplier used to make the bias voltage for electrostatics. The doubled voltage would end up about 800 volts, and is perfect for starting 3 tubes in series. You add a large value resistor in series with a .1uf cap and a diode and it will definitely popstart the gas tubes.

schematic updated

Item 1 is the filament transformer for the amplifier, used with item 3. Which is a diode bridge, 2 large capacitors and a resistor. Exactly the same as shown in the ES1 schematics i published. Runs the 6 tubes at about 2.5 amps total. The amp has a warmup/run switch which is why this extra transformer is necessary??? Otherwise the other filament windings in items 2 would suffice. Items 2 are the power transformers as shown in my schematic above. One for each channel. 800 volts center taped plus a 5 volt winding for the 5u4. Plus an extra 6.3 volt winding that is likely unused. Item 4 is where all the action is going to be. Too many parts on there and some are probably hidden (the fets). Another poorly made, impossible to repair mikhail hunk of crap. Its no wonder he never published pictures of any of his power supplies. It would be easy to just have the power supply fixed without having the amp chassis. The gas tubes have a starting current of 75ma, but a max of 30ma run current, no way that can drive a pair of WCF's. So unless mikhail is driving the crap out of the tubes (certainly possible) there has to be some kind of pass element. I did come up with a circuit to guarantee that the tubes light, but adding it to that fucking mess could be quite a bit of trouble.