kevin gilmore

I would leave it on a voltage gain of ten and not worry about it. Or if you insist on much less gain, you need to add a resistor to ground at the output of the attenuator for each channel.

Can you use a mosfet as a WCF. The answer is clearly yes. But why would you want to? The output impedance of a tube is very high, and WCF is a trick to lower the output impedance. The output impedance of a mosfet is very low, and no tricks are necessary. Now if you want to know what the closest thing is to a WCF as solid state, the answer to that is simple. Nelson Pass. Whose power amp designs really can be considered an upside down WCF. Both are single ended designs with an active current source. A standard WCF has no voltage gain, an inverted WCF has significant voltage gain.

google is your friend however http://www.cavalliaudio.com/cj/docs/WCFOptimization.pdf Tube CAD Journal: Tube regulators part 2, July 1999 and page 3 right after it. IMPORTANT read page 3 lots more about wcf at the tubecad site. And should another manufacturer make such a headphone amplifier, then you absolutely should listen to it. Why no one does may have to do with some of the conclusions of john broksie at the tubecad site. The capacitors thing is stupid to the extreme. If you were driving argon gas lasers which is what those juice cans are really designed for, then great. But for a headphone amplifier whose output power is 1 watt or less, those things are TEN THOUSAND times overkill. Capable of 25 amperes peak each. You show me a headphone that can take 25 amperes. As far as speaker amps, this circuit just does not apply. Now as to preamps, i do recall that someone did a preamp with a WCF as the output stage. I'll answer the other questions in the other thread in an hour or 2.

or variant thereof then certainly covers it, as it is still the white cathode follower design. On that unit, better to not open it up and see how the pass transistor was done, parts may fall out.

And now back to our regularly scheduled program. If you want the ultimate in coupling caps there are the audionote copper foil, silver foil, and even gold foil caps. Stupidass pricing. Not big enough for output caps.

From this quote and another after it, you have a mpx3, ppx3, or variant thereof. I thought you had an extreme. Anyway you have the only production headphone amplifier i know of that uses a white cathode follower. And therefore it has a sound signature all its own. You really need to open the thing up and take a look at the regulator section to see if it is burning its way thru the board. Because if it is, you need to get that fixed quick if you want the thing to last a while. The wheatfield is a class A cathode follower. Same as about 10 other amps including the extreme and menace. Has a very different sound signature. This is the signature i personally like. Although i certainly like my solid state pieces better. Here is an example of done right http://gilmore.chem.northwestern.edu/millet.bmp None of mikhail's stuff rises to this level of quality. None of it. Not even the stuff in the $18k range.

I use the yiddish definition of a shill. Slightly different. Mike and I agree on the last 5 things. The world is comming to an end i tell you... Earl is a rampant singlepower fanboy extreme. Maybe he got a few free tube adapters, but that is about it. Fred was (or still is) a rampant ray samuels audio fanboy extreme. (yet the only thing he may still own is a sr-71 )

Maybe some day you will hear the bamaslama which is the same as an extreme with dc output coupling. And maybe you will hear (or have heard?) the menace which is also the same thing.

mike has it almost exactly correct. Yes it was in fact the RS fanboys with what appeared to be very one sided and heavy handed moderation and censorship. Not the least of which was caused by tuberoller. Its not another agenda, although my love for ray is clearly well known. Being a shill usually requires some back channel money or favors going on, so earl is not a shill, and therefore we need a new word for this. Hirsch and earl are therefore fanboys in the extreme. Liking a piece of audio gear is great, loving the person that build it, treating them like a god to the exclusion of all else borders on insanity. 99% of mikhail's trouble is his own fault. Fact is that both ray and mikhail are charismatic's and people want to believe the bullshit that flows so easily from their mouths. There is really so much other great equipment out there from many different manufacturers that never sees the light of day due to the extreme noise to signal ratio.

I know of a total of 9 units. 5 of which are having trouble. Of those, 2 are in serious trouble. And 3 ES2 units. One of which is having trouble. Just goes to show how much of a liar mikhail has become. Stax just barely makes 300 pairs of O2's a year and i doubt every one is going to be hooked up to an ES1.

I think you are missing my point entirely. Its the rampant fanboyism over there that caused a lot of this. Mainly ray finding people to post about his shit over and over and over, burn in threads, isn't it purdy threads, and stuffing some of the moderators with free or reduced price shit so that they could continue the gravy train. So mikhail had to find a way to do the same thing. mikhail's version was a new amplifier every week. First the extreme. Then the platinum extreme. Then the extreme platinum. Then the external power supply. Then the bigger transformer. Then the tube external power supply. Then the gold plating. Then the pair of boxes so large. etc. Lets not forget the infinite amount of expensive capacitors. The whole mess turned into a my penis is bigger than your penis. The massive amount of stock required as none of that stuff is JIT. Problem is that there is absolutely no way to run a business this way. Not mikhail, not ANYBODY. The fantom shipping numbers, shipping one person's stuff repaired to another person (different serial number) is just plain fraud. Mikhail's works is anything but quality. After seeing pictures of the ASL stuff i put both of them in the same boat. Not a chance would i buy any of that junk.

Thanks to aaron for sticking his neck out on this. I'm sure his email and PM are very full at the moment. Maybe if a much tighter lid is placed on each and every fanboy, things can get back to higher quality product with a reasonable design cycle. All the manufacturers have been clobbered hard by the must have something new every 3 months thing. It would be nice if there was actually someone out there that could do complete custom work at reasonable timeframes and reasonable prices. This does not exist in the rest of the audio world, so there may actually be no way to accomplish this.

and this Moderator inquiry -$$$ Singlepower-Who here has money or amps being held by Mikhail? - Head-Fi: Covering Headphones, Earphones and Portable Audio ouch...

Ding Ding Ding... Correct answer. Massive negative impact on the community. For years now. If mikhails stuff was built like the woo audio stuff, no one would be having any trouble, or care what it costs. The whole bunch of proprietary technology is such a load of crap. Starting with regulated supplies that blow up and burn up then moving to unregulated supplies (that higher voltage thing) and now finally regulated tube supplies that cost more than the amplifier...Good stuff. But if hirsch wants to bring it on, then let it be so. I'm a big boy, i can take it. No one needs to defend me. I can't think of anyone left alive that could actually embarass or threaten me. Someone will move it to a seperate thread when necessary. Gotta go, busy day today.

If you don't know what you are doing, then the only way to actually LEARN, is to try. It's not rocket science. I know a complete newbie that built a BH. And got it to work. A lot harder than fixing a simple broken resistor... Did anyone see germania's construction of a millet starving student over there

Same kind of stuff hirsch did over there where he told the guy who was fixing his es-1 not to mess with it and send it in for warranty repair. And we all know how long singlepower warranty repair takes. A number of people are going to be repairing their own units instead of sending them in. I see this as a win win situation.

NO. amplifer ground! Earth ground ties to the chassis to prevent the chassis from becoming electrically hot due to some massive component failure (like a shorted power transformer)

I claim MASSIVE bullshit. Most tube amplifier manufacturers have bleeder resistors across the power supply capacitors. And a resistor to ground after the output capacitor does exactly the same thing. Singlepower amplifiers certainly have these safety resistors. One of the very few things mikhail gets right. If the thing has been off for more than 30 minutes and is unplugged, it is safe to work on. Its all about expectations. When you are spending $2k or more (way more) for a product you expect it to be built like other products in the same price range. You don't get that with singlepower. You get a hack job.

yep, pretty low resolution. If you need a place to put the pictures email them to me. Look at the resistor labeled mexico in the first picture on the right side next to the one capacitor. Does seem like some definite burning below that resistor. Or the camera may be playing tricks. Looks to be the original version of the extreme made from a ppx3 circuit board. I'm pretty sure that some of the extremes did have a regulated power supply... Gotta find that picture.

Since its past the edit window, i see where the last statement might be taken wrong. It should have read If i was going to build and SELL es-1's it would be with a fully regulated power supply... I'm kind of busy lately and not paying complete attention... This was yesterdays thing, and boy am i sore... http://gilmore.chem.northwestern.edu/bruker600.jpg this is today's thing http://gilmore.chem.northwestern.edu/newmaldi.jpg tomorrow i'm gonna rest

I built the amplifier and used a BH power supply since the voltages are identical. I added a bench supply for C-. It was a prototype for bench use only. BH supplies are very convenient to have spares of laying around. They will run just about everytning. Of course there is something new and much more trendy.

Good idea. I have a better one. Jude needs to call mikhail and straighten this out. It would not be the first time. If jude does not hear what he wants to hear, then jude can take the appropriate action. I don't think that other people should be repairing mikhail's mistakes. But it may get to that point.

I know what an es-1 sounds like because i have built the identical circuit with the same output tubes as the BH. It can be made to sound very good, but has a different presentation than the BHSE. If i was going to build an es-1 it would have fully regulated high voltage supplies and a servo for the output tubes to keep the bias stable without having to measure and mess with it. It would not be infinitely adjustable for every single kind of input tube or output tube as this is 99% the cause of all the trouble. aaron is not having a lot of luck getting people to publicly say over there what they have paid and what they are owed, so unless a lot of people come forward, this will just sink back under the noise level till things get really nasty.

You are kidding right??? The older stuff is much worse. MUCH WORSE... lots of air mounting of parts. Maybe in few weeks i'll post some of the really horror stuff. Its pretty much a reverse price thing. The more expensive it is, the bigger a piece of shit it is. Just remember it's art, not science.

I had not posted pictures of the es1 before. I will now. http://gilmore.chem.northwestern.edu/es1inside1.jpg http://gilmore.chem.northwestern.edu/es1inside2.jpg People: please stop calling me at 2am. REALLY. I need my beauty sleep. This is not my fault. This is not my problem. Believe me, over the last 3 years i tried to get mikhail to listen to reason...The more i talked to him the more he went over the deep end. Making lots of new stupid shit may be a fun thing, but it is no way to make money. So that we are all clear on this, none of the pictures i have posted are mine. They are from other people who have sent them to me or posted them. I have plenty of pictures of my own, but posting them would show temporary possesion of various items, and since each one is different it may point back to the person who owns/owned them.