spritzer

I think most high end Stax owners have 009's, doesn't mean they use them though...

There are no products I'd recommend over all. Most good vinyl re conditioners will work just fine. I've thought about making aftermarket earpads so something for the todo list I suppose. Wouldn't be cheap but the Omega's are worth it.

That wouldn't be a problem.

I wouldn't use leather cream on the earpads as well...they aren't leather. They are vinyl so they need some plastic treatment instead.

I always liked the 202 but it's been way too long since I had one for any meaningful comparison. Going by the basic difference between the x0x and x07 series the 207 would be a bit brighter with a more open top and tighter bass.

Also...electrostatics.

Ahh yes the voicing thing, does anybody actually believe that shit? I mean it takes a complete lack of understanding on how things are designed and how amps work to pull that off. It is quite clear that all of our amps are basically wires with gain where the only real limitation is down to the topology and the parts used. That was the initial plan with "special 009 amp", find a circuit and components which would deal with with the sub-par bass and treble/upper midrange performance in the same way the HEV90 dumbs down the HE90. Something like the Blue Hawaii would have been a natural starting point as it starts rolling off in the audible treble region (which is why it sounds a bit dark and boomy at times) and to roll on from there. Given that Stax are trying to fix the 009 it was a bad idea to try and design for a moving target. Still this wouldn't be voicing, more finding compatible transducer and amplifier pairing which has been a cornerstone of audio through the ages. The bottom line though is that you can't voice amps if you want ultimate transparency. You can throw feedback at, change the topology, run devices at the wrong operating point etc. it to alter the sound quality and the performance of the circuit but I don't think anybody would believe that is done with the aim of making an "honest" amplifier. All of this also stinks of the same BS as the whole burn-in mess. There people assume a certain gold standard, that they hear like an AP measuring station so it has to be the component that is changing. I mean it couldn't possibly take a while for our very flawed hearing to get to know a component and break down our own mental blocks? Nope, has to be the thing we can't prove or measure in any way, which is the but of all jokes when you talk to engineers. Yup... makes sense... Same thing here, why is the amp blamed as bright when all it is doing is amplifying what it is fed and driving the phones to its best ability? It isn't possible that the source is bright (which many, many are now) or there is something wrong with the transducers when they are actually fed properly? None of this makes any sense to me....

I like it. The 009 does belong there and there are other crazy expensive sets which also can't quite live up to the hype. The Orpheus was so far from being neutral that it wasn't even funny, large parts of the bass spectrum simply missing and the top end only sounds ok if you feed it through a broken amplifier with enough polyester caps in the signal path. Let's not get started on that soundstage or what ever it was supposed to be... Sony R-10. Nothing wrong with them except they have a very unique sound but my gripe is people paying way too much money for something nobody can service and where the crucial foam parts are degrading so they will never sound right.

Having built hundreds of these PSU's over the last 10 years I know they will only act like that when there is a short on the board. Now what's causing the short can be a number of factors, sloppy soldering, flux or just a sub-par PCB. It is so often over looked that PCB's aren't the same and some are just crap. Are the pass transistors sourced from Mouser? There are some fakes out there which could be a factor...

One more data point on the 207, to date three of my KGSSHV mini's have been bought by recording studios as the final mix monitors. I'm not allowed to name the studios but they are...well known... let's just say that. Anyway all of them use the 207 for this even though price really wasn't an issue. Granted they need to take into account just how much abuse they must suffer but primarily it was the sound. I must say that the measurements Tyll did helped a lot as honestly, how many chains will give you these THD numbers? This is at the same time that there is some consensus on HF that the KGSS is super bright and the KGSSHV even more so. Everybody knows that the KGSS is slightly on the warmer side (due to the third stage lack of CCS which I countered in Tyll's amp) and the KGSSHV is pretty much dead neutral. If it is bright well then how about looking at the phones or the source? These amps are wires with gain (and a lot of it at that) so they must naturally be the culprit. Yeah that makes sense...

Some vinyl cleaners work wonders but it's a trial and error stuff. Take care of those earpads as there are no replacements. *Raises hand*

That is indeed the issue. The core sizes for the R's are fixed but the Chinese manufacturers don't care too much about that. As for posting pics, that won't work as out of a batch of two, one transformer might be fine while the other one is garbage. Some have been truly terrible with dangerous lead wires and truly terrifying build quality. The bottom line is that I'm staying with toroids for now.

It should be enough but I never measured the current draw of the SRA-10S.

It's from China and some are ok, others cause a lot of issues.

Nope, my own version of the BH circuit.

I have a PS-800 as well and I've never had a tip become loose. It is the PS-800e (or something like that) so they could have updated the pen for that model.

OKI/Metcal PS-900. I use two of them and wouldn't touch anything else.

The plates are gold anodized...

Well with Toroidy one never knows but I'm running at 160mA on my way over spec transformers with no issues.

The EHT has been refurbished plus some other fixes here and there but I know that 48 year old panels aren't working correctly. A refurbed unit will not sound the same as it will be working correctly.

I would move the transformer further away from the volume control as it is so prone to pickup noise there. Ohh and you need at least 12mm stand offs if you want to mount the boards directly to the sinks. My latest ones have all the holes removed to make mounting this way easier.

Gotta do some dynamic amps as well. Show people how they should be done as there is an awful amount of crap out there. Late last year. There was a local set for sale that I tried to avoid but I finally broke down when the owner called me out of the blue. Apparently it is known here now that I like electrostatics... They are just sitting unused for now but I'll probably ship them out to be completely refurbed.

The Susy needs max 10K so I had to use some of my TKD's.

As I've been promising to do for months I'm finally working on some dynamic amps. Here is something new, a Susy Dynalo with switchers... Running at +/-18V there.

They might just do that sitting there. I do wonder if these utilize the particles found in the Jade. Basically the diaphragm was covered in some gunk on purpose which made them far from silent when sitting idle. Such epic stupidity is quite hard to fathom...