spritzer

I would always recommend swapping out the card slots on these as they all fall apart. Also, watch out for the transformers leaking... I found that out the hard way as they aren't grounded. Wasn't there just one pot per channel on these? Should be the balance so go to each tube anode and adjust for 0VDC.

I would just leave them in if they work fine

Yeah and it is 2SA... that is always a PNP.

It's an NPN so no... not a replacement. There are no PNP parts that are past 600V these days.

The voltage limitation of the tubes is an issue but the CCS does wonders to the amp.

That's pretty much how the Stax tube amps sound in stock form... not a whole lot of dynamics on tap there with those tubes and resistors as a plate load

I'm not sure if they have been posted out in the public yet but should be soon.

There is the EX-1a too: https://www.eslabhk.com/ex1a The prices are also very fair and I will be buying both.

I can't wait to try them.

Plus it has Apex chips in general so it is awful.

Gotta love Edifer making worse parts at three times what they used to cost. Still that price in Italy is just a ripoff, the arc from Stax directly in Japan is 6600Yen which is about 50$.

Yup, transformer in each cut and weight is close to 1kg. I rebuilt one 15 years ago and recently got the urge to mass with one again. 700V bias (well cut off so probably lower in practice) and I'm going to put new earpads and a headband on them.

That's what I was thinking, the margins must be insane on these as its a store not really known for any good deals. Now I'm thinking if I did a deep dive on this earlier in the year when I got a set dirt cheap... or I just sent all of that to Kevin? Well first off input, bunch of parts here USB xmos, A/D etc: All of this leads to a pair of ESS 9028 dacs: Not the best picture but that looks a lot like filtering to try and make up for the utterly retarded driver design: Finally output stage... yeah this is pretty dire. Remember this thing is 4k$... Now how does this thing actually work? The clue is those two gray caps and the wires going to the headphone plug. 450V B+ on a single rail so shall we say a maximum voltage swing of ~840Vppss and the bias is clearly 2000V. The bias is superimposed on the audio signal after the output caps and then we have the grounded shield, that's it. These are even simpler than what Koss were doing in the 60's where the back stator on the ESP6 (and 7, 8 and 9) are grounded but otherwise normal electrostatics.

I don't think Warwick are doing so hot these days... I snapped this in Selfridges on Oxfordstreet yesterday and I might have been tempted as an insane collector if I didn't already own one of those piece of shit amps. Well that and it sounds like shit... there is that issue too.

Unless it is a set with the handmade markings and the slightly smaller housing, they are all 200V bias so any normal bias would work just fine. I'd remove the cap after the ballast resistor just to be sure but that's about it.