kevin gilmore

yep, wave a piece of paper over it, the thermals change and the offset drifts. for 18v rails, that is a good current.

someone please check these http://gilmore.chem.northwestern.edu/kgsshvcarbonv2.pdf http://gilmore.chem.northwestern.edu/kgsshvcarbon.jpg

this one, the servo is integral and required. Same as the T2

I like it.

I think if I design it carefully enough you can put 2 boards together, one is double layer, the other a single layer.

just tried it, very little actual ground plane due to all the wires. eventually when we go to all surface mount everything, the board will be at least 3 layers.

I was thinking those other resistors might be the plate resistors, but then what are the ones in between the caps. Anyway with the resistors not lifted off the board, the same thing will happen that has happened to the kingsound amps.

certainly can replace the reference with a to92, current datasheet does not list the pinouts. I did trim the emitter resistors to 25 ohms, so there is still about 9v on the servo. But will change values to the final parts when we all decide what those are. also added a pot in series with the 20k resistor to adjust the dc to exactly zero. the 25 ohms decreases the thd a significant amount at 20khz because of the added gain. let me know which parts and values to change.

no, just 2 transistors for the servo output drive. identical to Kerry's schematic. the final output is the Motorola part because its about 350mw and if you turn the current up, its more like .5 watt

latest version with correct resistor values for Kerry's servo http://gilmore.chem.northwestern.edu/kgsshvcarbon.jpg parts set for 16ma at 450v

i will start. very simple power supply, roughly same as original BH supply at lower power, zener based. definitely drifts with temperature. resistor based output tube. See JimL posts on current sources. And the resistors look like 100K which is extremely inadequate, but match the power level of the tube.

no difference between the 2sc parts and the pzta or mpsw or mpsa parts 1486 does not need heatsinking. About 188mw

50 years is the golden anniversary 55 years is ?? in 5 more years, 60 years is?? and this is what happens when you edit an edit of an edit of an edit...

its getting pretty tight... http://gilmore.chem.northwestern.edu/kgsshvcarbon.jpg laying the rest of them horizontal is going to be a bit of trouble.

but but Mikhail said that a 6sn7 and a we421 were identical. and 6j6a and 5844... And he consistently shoved all of them into the same socket to prove it. (with adapters) and god only knows how many other tubes. and 3d21 In place of 6ca7...

the version of the carbon board i am working on has pzta42,pzta06,pzta56 and at the moment mpsa06 and mpsa56 all of these parts are current fairchild production i have been told that all these parts have at least 5 years more life left. i have also been offered this really nice bridge in SF recently painted... the stn9360 lay down because they need to dissipate a bit more heat the pzta parts stick up vertically, and are therefore real easy to solder in. i have also added the cascode to the carbon. should be 100% mouser parts except for the lsk170/lsk389 which are easily available. with 20ma per leg, should make the current crazies happy. and 32 watts of heat per channel getting kerry's servo in there is going to be fun

the new verskon uses the bc parts

yep grounded gate.

you want a transformer that has 360vac windings you change the 440k resistors to 390k

that schematic is close enough i'm redoing the kgsshv-carbon board for current parts, i added the cascade current source, is there anything else people might want?

coconut audio (patrick82) did stuff like this... be careful, its a slippery slope

when i do them, its a 3 step process per hole. which is why it comes out so nice. even though i'm using full up commercial NC mills, if i just drilled the holes single step, it would not be perfect. first you use a centering drill then you use a small drill bit then i machine each hole round with the mill bit now it really does not have to be this perfect, but its only a few minutes extra per bracket

what I do is float everything in the chassis. The chassis is connected to earth ground. everything else floats and the audio ground does not touch the chassis ground. this is easy with xlr connectors as the inputs only, and then rca to xlr adapters for single ended.

that is the company I buy from, but I go for the Teflon. its more expensive, but I have the right stripper and always liked Teflon.

raise the value of R1, say 1k will give you 3db more