kevin gilmore

Andy built one, and so did I. Maybe a few others that i don't know about.

There is a better way to make output transformers. Just like Mcintosh did on their 150 and 300 watt tube amps way back when. A total of 4 output windings, bifilar wound with the primary. In this case, lets say each winding was designed for 120 ohms. All 4 windings in parallel, and you have 30 ohms. 2 windings in series in parallel with the other 2 windings and you have 120 ohms. All 4 in series and you have 480 ohms. Perfect for all the popular headphones out there, no resistor loading needed.

The new dynahi is balanced only. Its the only way to do supersymmetry. You can actually use one side to ground, but that is not the point.

opa445 can handle up to +/- 45 volts for the 7815 you jumper pins 1 and 3 for the 7915 you jumper pins 2 and 3

Thats a lil-knight thing. I do like the bipolar thatcorp 340 as the input device instead of the jfets so maybe i'll do a version of the board for that. Its definitely sweet on the multiamp. Until linear systems pulls their fucking heads out of their fucking asses.

Last group buy board. Labeled as dynahi version 1.0 copyright 2004,2011

You have to jumper across the regulators

You are really going to like the new supersymmetry balanced dynahi, and the multiamp (multiple feedback option balanced dynalo) Both stuffable with currently available parts.

Correct. I have tested the plastic on the 4686a (collector to sheet of metal underneith it, bolted tight) to about 2kv before breakdown. You can put the aluminum oxide insulator in, but it adds unnecessary thermal resistance and you don't need the voltage protection.

And you still need some thermal grease, or the silicon impregnated washers on the 4686a. Same thing on the ixys part, thermal grease is better for that and it goes on both sides of the ceramic. Just a little is all you need. Any more than that makes a mess. And nothing electrically conductive either, like arctic silver crap. If its not white, you don't want to use it.

The 4686a parts are already isolated, so they don't Need the ceramic insulators

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.