spritzer

The bias supply is also the incorrect polarity and I for one would completely redo it. It has enough headroom to regulate it or do a better voltage divider and a dedicated ballast resistor on it. The output devices are also mehhh at best. Output capacitance is 106pf which means the output of the amp is higher than the headphones. The Cob should be as low as possible so this is a problem and will severely color the sound. Think Cavalli Liquid Lightning

It wouldn't surprise me that this comes from JR Audio. Same crappy wiring as they use and other silly build ideas. They have also been cloning my amps in the past.

This one came to an end this week as I finally got round to turning the amp on and testing it. Busy summer and all that but here is what this should have been in the first place: Old school KGSSHV build only using the input sockets on the back, that swanky gold IEC and the volume control. The rest was all garbage...

The ESP6,7 and 9 were all single ended so the amp won't like that at all if you've somehow connected the back stators together. You can isolate them though as I did back in the day on my esp6's.

I wasn't sure about posting this but it kinda had to be done. Pic is from HF and the usual nonsense in the peanut gallery there: So this is the Sirrah V3 from high-amp.de...aka yet another slight twist on the Stax SRM-1 Mk2 or derivatives. For me it is just the build here and well... the total shitbox we have here. First off, what's up with all the hotglue? As somebody who has built hundreds of amps at this point... I don't even own a hotglue gun nor would I ever think of using this crap. Some other goodies, top of the transformer sanded for it to fit in the chassis, no insulation on the mains plug which means this would fail even the basic CE tests, nice bit of cloth underneath the pot there to presumably stop it from shorting something on the board and I just love all the transformer leads, not twisted in any way, coming really close to the input wiring. The hand cut heatpads on the output transistors are also nice and I very much doubt that tiny ballast resistor for the bias supply is rated to 600V.... On top of that, look up the design of this thing. Basically a SRM-212 with a full size power supply and some things changed. +/-200V rails, no CCS for the VAS stage and very little power.

Seconded

Yup, that is the same as on mine. I'm just going to order a custom made transformer which will also allow me to have some fun with the amp over all.

It's worse on the 006tS I just got, there is only a 100V winding and nothing else. The cut wires can usually be restored with some precision surgery but with just one winding, nothing can be done except a new custom made transformer.

Post some pictures of the inside towards the back of amp as there is no single way to convert them.

There is nothing wrong with DIY and we try to make the PCB's as simple as they can be but it is a whole other matter to sell that DIY design after butchering the basics...

Ahh my ebay feed is such a rich source of crap. Now this: https://www.ebay.com/itm/184390225946?_trksid=p11021.c100851.m5053&_trkparms=aid%3D1110006%26algo%3DHOMESPLICE.SIM%26ao%3D1%26asc%3D20170803121420%26meid%3D7c8a959dd9b44639b572f30ba9d29c74%26pid%3D100851%26rk%3D4%26rkt%3D4%26mehot%3Dnone%26b%3D1%26sd%3D143674134487%26itm%3D184390225946%26pmt%3D0%26noa%3D1%26pg%3D11021%26algv%3DDefaultOrganic&ul_noapp=true Pics here for when the listing goes down. Standard KGSSHV but with a few twists: Notice that their are no terminal blocks which is bad but one bonus, this amp will kill your headphones. Can anybody spot it? It's not the twisted output leads which are a terrible idea... The bias is tied to the "bias tp" which is just for measuring the bias... before the ballast resistor!! So yeah, no ballast so say goodby to your diaphragms.

Stax SRM-1 Mk2 and upwards.

I'm not sure where I wrote down the pinout for the Monoprice headphones so I'll have to dig through my archives to see if I can find it. If I find it then I can make adapters as soon as the local store opens up after the long holiday here. As for getting the most out of these, an amp upgrade would be the first port of call.

All Stax are balanced and even if an amp has two outputs... they are wired in parallel with both channels at both sockets. What benefit could be had from this is very dubious.

I agree, those are very nice indeed. Could be old stock but I doubt it. Most likely Stax just enjoy messing with us...

Is it a Mk2 or an A unit? Also, this week in stupid: https://www.ebay.de/itm/124250502104?ul_noapp=true Here are the pics in case the listing is taken down: So somebody chopped off the Stax plug on a Mk1 and fitted two for dual mono... why I don't get but then stupid is hard to understand.

Good point so the empty warranty card points to a Japanese unit and the sellers who export never fill out the warranty cards.

Stax serial numbers are in constant flux so no idea really. SZ2 and SZ3's were being sold right back in 2008 so could very well be. The dealer is supposed to fill out the warranty card but some don't do it.

Thanks for that and I had a lovely day. The weather was just about as nice as it gets in Iceland with great people and even better food.

No, none of the amps are left here but it is a very noisy thing. Plenty of high frequency noise in that thing.

Yes.

The bias in the E90 is run off the HV+ line so 600V. That is fine for Stax but the issue is that the ballast resistor is not the right value and there is a cap after it. Now you could just place a 4M7 resistor on the adapter but I prefer to go into the amp and modify it with a voltage divider and moving the cap. The issue there is opening up the damn thing...

Speed holes...

Those parts from Nikko were probably here as I returned them a decade ago as fakes. They did find real ones to replace them back then but yeah... took back the fake ones and are probably selling those.

Also cheaper not to buy the fuse insert. Clearly saving the big bucks here...