Tachikoma

I've heard of the knob coming off too easily in these amps, but never a case where the "inner knob" won't come out. It sounds like it was dropped and that somehow bent the potentiometer.

Some people have advocated using legging socks to replace the grill material.

That's neat, have you tried just replacing the foam in your old earpads? I think taking the springs out of the old earpads improves both the HF and LF response (possibly by improving the seal), and I see that you aren't using them with your new earpads. Is there any change in the soundstaging with the new earpads?

Happy birthday Wachara!

Heh, if you look on Taobao now, there's an ad for the Megatron as well.

Just wondering, what is the bias circuit used in the SRM-252S? It would be a lot safer to work with 12VDC than mains AC.

Does anyone have an opinion on the sorbothane damped Staxen?

Nah, they just call it new toy syndrome instead.

The M22 is a class A amp and heats up a fair bit as it warms up, so if it has nothing to do with the caps, then its most likely a resistor somewhere that's drifting I suppose. Just about everything else (transistors too) was replaced. Too bad no one has the leisure to organise a DBT for burn-in.

There is something called "new toy syndrome", but do capacitors not take a while to settle? About a month ago, my Pioneer M22 with newly fitted electrolytics took an hour to warm up before the channel imbalance would go away, now that warm up time has all but disappeared.

I'll take a set.... which will maaaaybe someday get populated, lol.

I didn't think they were THAT bad when I had them, although I didn't think they were anything special either.

http://en.wikipedia.org/wiki/Amorphous_metal_transformer

Err... that's the dust cover (and the "back diaphragm" is also a dust cover). There's only one diaphragm, and its in the middle of the driver, which you will not be able to touch with post it while its playing music lol. If you did find a small hole in the rear dust cover, try to patch it up with a very small piece of tape. For reference, the diaphragm looks like this: http://tcengineering.files.wordpress.com/2014/01/img_2641.jpg The stators are the metal plates that sandwich the diaphragm. These are the only parts I would touch with post it. (http://tcengineering.wordpress.com/archive-of-projects/electrostatic-headphones/) It really sounds like you haven't actually disassembled the driver, so why in the world are you having imbalance issues...

The dust covers should have no effect on the channel balance. There is the possibility that you didn't reassemble the drivers perfectly (say, something was at a slight angle), which will cause an imbalance, so just pull the weaker channel apart and put it back together again. If that doesn't work... maybe flip the diaphragm around, it _might_ make a difference if its only coated on one side.

It was an utterly fubar set of drivers, so I had no qualms doing that - it did solve the problem though. My thinking was that fingers leave no residue (other than a little oil), aren't overly abrasive and are sensitive to boot. There was a surprising amount of dust stuck on the membrane, which I could feel with my finger, that simply would not come off any other way, besides sticking it under running water. Yeah, tapes that leave as little residue as possible would be good.

I'm not sure why the tape being too sticky would be a big problem, you're applying it on metal stators, not plastic. I felt that the most difficult thing about cleaning out the stators was to not overstress the bias connector that connects the two sides of the drivers.

Yeah, if you're clumsy the way I am, small strips of tape are the way to go... wouldn't want to accidentally get tape on the membranes/dust cover. Chances are the dust cover has a hole somewhere too, so try to patch that if you can.

Very. My loudly squealing drivers were dead silent after I went through them with some sticky tape. I washed my membranes in water and recoated them before, though. Disclaimer: I wouldn't recommend washing and recoating the 009 membranes. it took me a great number of tries before I could get them balanced, and now the drivers are normal bias only. Re:cleaning the diaphragm. I did have good results from lightly wiping the membranes with my finger, but again, probably not a good idea with a 009

What n3rdling said, and use sticky tape to get dust off the stators as well. Just do it yourself imo, if only to save time.

The left and right outputs are high-pass outputs? I get this feeling that simply combining the amplifier outputs won't work...

I've just started listening to my Pioneer M-22 + ECA-80 combo, and my first impression are: Wow. I wonder how long this feeling of wow-ness will last, everything just seems so much .. real-er and more tangible through this setup than my SRM-T1.

To be fair, so does FrankCooter's amp... granted the EL34 isn't an 845. At least this one has a chance of being decent since they can wind their own transformers.

Yeah, they have, but with a complete dearth of information (in English) about these amps, it would be nice if someone knowledgable would take a closer look at them. I'd try my luck with one of those 45 headphone amps if I had a dynamic setup, 100% positive feedback on YJ should mean something. It seems that this is the "Hatt audio lab" YJ account, and the company also makes and sells output transformers, which may account for the low prices. Also I think the tubes aren't included in some of the amps.

http://page10.auctions.yahoo.co.jp/jp/auction/m95216502 Birgir, would you mind getting one of these and let us know whether its any good? It could be a Woo WES at half the price (at worst), but I do wonder how good this guy's amps are as he's selling some really interesting DHT amplifiers as well (845, 45 etc).