spritzer

I'm sure there are some black SZ2's though I've never owned one. I prefer the silver and black which can be seen on all of my amps...

As I've been discussing this with Antonio, I've recently received a SZ2 Mk2 that is utterly mint. I assume they were just removed from the box in 2007 for a quick listen and then placed back as there wasn't a spec of dust on them. Stock they have that SZ2 sound and pretty terrible fit on the head. The earpads are way out there and the port wide open so everything is diffused with mad bass. Modified with Mk1 springs and a plugged port they sound awesome though. They have that ethereal feel of the Mk1 with bass that would make the LCD-2 jealous and the best soundstage there is. Me like... Yes and no... The SZ2 version was pretty much open at all times so they just breathed easily when lightly pressed towards the head. Force them and they will fart but the port is mostly open. The SZ3 OTOH is better executed so the port is mostly closed when they are placed on the head. They won't fart as much when placing them or removing them from the head but once settled they will far. Doesn't stop them from sounding horrid though... The mylar will last for a long, long time if properly cared for. It is isn't exposed to direct sunlight or driven hard enough for arc's to take place then it should be fine for the next 50 years on those SR-1's. What can perish is the resistive coating on the diaphragm as the old ones were carbon based so they can absorb moisture. Smoking near the sets will also kill them far quicker as any deposits on the diaphragm are not good. While something like the Quad speakers will require pretty frequent servicing that isn't true for Stax headphones for a number of reasons. First of all sunlight as that is the great killer for any ESL, second is the far higher voltage and lastly, pretty crap engineering on how the transducers are made on most sets. Take the Quad ESL57 for instance, drilled plates in a wooden frame with awful tolerances while the even the first Stax made just 4 years later looked like this: Stamped brass stators in a molded plastic shell. These have issues as does everything but the core design is still found in the SR-009...

Everything degrades with age but I have some Stax SR-1's here that work just fine and are ca. 50 years old. Not many dynamics last that long... Press the cups towards your head while wearing them.

I use red spirit (burning alcohol) with good results and the plastic is unharmed.

I would let the amp warm up to it's full running temp before adjusting but yeah, that's the procedure. Same as on the new KGSSHVk boards. There is also a jumper connection for the servo so you can simply engage it that way when you want.

Razor blade also works well

Goes to show just how fucking complex this PCB is. Also servo was added without enlarging the board... No space for connectors if the transformer was mounted to the back panel...

Zero chance Stax would ever do something like this. First off they would fuck with the circuit to make it "warmer" and then try some further tuning to make up for issues in the transducers. EI or R-core transformers would work just fine but both are difficult to get as one off units at a sane price. Your chassis must be far bigger as no way a 300VA unit would even fit in these one. The transformer in there is a 100VA unit. The F5 also needs a far larger chassis to have any hope of staying cool. Something like this then: This one could perhaps work on a scaled down F5 as the sinks are huge. A word of warning though to anybody who might buy one of these, the anodizing on the sinks washed off with the cutting oil after I tapped the holes. Clearly a quality finish...

Tempted to buy one for shits and giggles. A bit funny to think this came from some Sunday afternoon boredom on our part...

Is there anybody on that site that isn't retarded? They are very much in favor of "new and shiny" over anything that makes sense. Looked at some internal pics of this BMC, holy fuck this is bad. The agenda was clearly to use the cheapest crap known to man everywhere...

Some comparison shots, remember that the 727 is the exact same size as the 007tA... Suck it Stax!!!

You know Ari that those are just minor issues that get in the way of the glorious tube sound...

FR4 and 4oz like the original test boards. Only two layers on all of our amps... That's the general idea, fix those small issues such as a proper way to do the test pads, redo the input a bit to suit my particular needs (hello loopouts) and the like.

I solder everything where I can. Can't stand the pluggable stuff. Edit: Ohh and this amp sound fucking fantastic!!!

I will be ordering amp boards soon but I'll need to make a new version first. It needs some changes...

...an hour or so later spent wrangling wires it was alive. I went for orange as the power indicator to try something different... No hum noticeable with the headphones but I'll measure it when I get a chance. Running at 9mA and the sinks get warm but not hot. Next one will be run harder but the really neat part is that aside from the 2SA1968's everything is in current production.

Ehhh... not sure there is anything I have left. I need to fix up my SRA-14S and sell it (need a new transformer like they all will) but nothing else I'd want. If I find a broken T2 I might buy it just for fun.

Said fuck it to other things requiring my attention... It lives but I haven't done any testing except for balance/offset etc. Now for some not so fun wiring...

If I can find the time then I'll start testing it today. That plus another small HV...

The output tubes sit at +600V so it's easy to generate Pro bias. Not that it isn't always easy to generate it...

I'll wash the front panel clean and then have the new graphics laser etched which will not wash off... ever!! I'd just have thrown that SRA-3S in a bucket of water. Been there though as one of my SRA-12S amps was filthy to say the least.

Happy Birthday Doug!!!!

Happy Birthday Douglas!!!

I mean the Stax ones aren't that great but I've never seen a brand new one split into pieces like that.

It really depends on the contacts and their quality. I suspect they are the same as the teflon units so you should be fine. That's assuming you are referring to something like this: http://www.ebay.com/itm/1pc-9pin-Ceramic-Tube-Socket-Machine-Made-Gold-Pin-for-12AX7-EL84-6922-New-/130674502828?pt=Vintage_Electronics_R2&hash=item1e6cceacac