kevin gilmore

I did a lifetime buy for me, and they already shipped. Stock up now, or be sorry.

self bias was always a sleezy (and by that i mean cheap) way to avoid the extra power supply, decrease the gain of the output stage, and increase distortion...

Should be enough offset range to handle this

Probably makes no difference, but should be 15v

I don't think i was capable of doing work that nice with a hand drill even 35 years ago, i always found a way to get to a mill, but without a nc readout, it would still have been a pain. It needs a wood knob! Making an ebony knob that big without cracking could be quite a challenge.

It will still have output tubes.

And i have at least 2 more projects planned for this year Pretty insane.

No other circlotron I know of has input or output transformers. Pretty sure that is verboten If you read broksie's write up on circlotrons, it's just another version of push pull With the center of the load as ground.

for those that want to scratch heads further... http://gilmore.chem.northwestern.edu/m60-power-117.gif http://gilmore.chem.northwestern.edu/m60-signal.gif

us patent number 4229706 if you read the schiit material carefully you may notice that it says dc coupled input, and dc coupled output. Which means that like the atmasphere, there are capacitors between the voltage gain stage, and the output stage, which can be really good caps because they work at low voltages, and into high impedances. Here is the original sumo9 schematic for you to scratch your heads at. http://gilmore.chem....n.edu/sumo9.pdf pretty sure the approval signature is JS.

I'm aware of the new schiit amp, and I think it's a great idea and a great price. No one has done a circlotron amp for headphones before. Jason was an engineer at sumo when bongiorno did the patent on the solid state Circlotron. (sumo 9) so you can safely assume that this amp is going to be similar I'll add the patent number later

Well I always use an analog preamp to do the volume. And I don't think there is too much gain. The schist amp has the same amount of gain Never liked digitally done volume

Birgir is going to make prototype boards soon

The LF is a rip on a early 1980's design with the jfets replaced by tubes, and vertical mosfet outputs replaced with standard international rectifier parts (now vishay). Not bad, not great either. Power supply limits current delivery especially on inefficent headphones like he6's. A single gain stage, no feedback design like some of the pass labs amps, or the circlotron it ain't. A S-30 blows the crap out of a LF for about the same money, or less used (if you can find one) and drives he6's or LCDX with true authority. And rise and fall times more than 50 times faster than the LF.

At least for lcd2's i have not found a tube amp that makes them sound right. Neither OTL or transformer amps sound right. Well except for an atmasphere.

Thanks for trying. Was worth a shot. When is a standard not a standard?? Pars you are up... But really, shouldn't the board house do the panelizing for you??? (without charging you a setup fee?)

all the files are there and seem to work, the extra file can be ignored because the tool sizes are in the echelon files ??

try this, but the sizes are in the one extra file http://gilmore.chem.northwestern.edu/doug.zip

Newest version of the blackhole amp is 3.45 x 3.67 inches http://gilmore.chem....u/blackhole.zip not done in eagle however.

Very Nice

Fully loaded, on the 20v lines about 500ma On the 15v lines about 250 ma 12v line peaks of 30 ma 5v line I gotta look up

Have not even thought about the power supply yet. In the simplest version the smallest power one tripple works great. If you go with the outboard amplifier modules then you need something that does +/-20, then you can regulate that down to +/-15 with simple 3 terminal regulators, and +12 to drive the relays.

I modified the kgsshv power supply and batepower boards for the next board run. Bias is now a 3 pin connector, TST which is the 580v direct, 580V which is after the 5M resistor and the ADJ which is the center of a resistor divider for any other voltage. If you have a 10 meg input resistance dvm, then the correct voltage measured after the 5M resistor would be 386V.

Each balanced board should pull 600ma on each of the power supply lines.

courtesy the stax mafia http://gilmore.chem....sr1_sm_sony.pdf