The Headcase Stax thread

[spritzer]

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. 

Edited November 29, 2024 by spritzer

[mikeymad]

65% off?! - they must have low overhead.... 

[spritzer]

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. 

[Craig Sawyers]

I had a pair of ESP6's in the mid 70's. Those were the self energized ones with a transformer in each earcup? I remember that they were not light. Sounded good as I recall, but listening time was limited by the head crushing weight and the sweaty fluid filled earcups.

[spritzer]

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. 

[lupoal]

Hi everybody,

I have a 300 Limited and, unfortunately, I stumbled upon the problem of the very poor quality arch... despite the fact that I used it gently at one point, already on the head, the arch broke in two (I put a photo here)

I made a repair with harmonic steel lamina and two-component structural adhesive and it seemed to be fine...but it snapped again right next to the lamina edge... the plastic that Satx uses for this detail really sucks

now I inquired for a replacement part, Stax no longer sells only the arch but now obliges to buy the whole assembly... the problem is that the original one mounted on the 300 Limited has proven (you can find several examples on the net and confirmations on Facebook among Stax owners) to be very bad, to improve quality at "normal" level it would then be necessary to switch to the Arch Ass'y MK2 which however costs, here in Italy, 380.00 euro! (these Stax people must be completely crazy to ask for such a price)

now, I would like if possible to avoid being sodomized by Stax forcing the purchase of a replacement at great expense to fix a serious quality problem of which they cannot be unaware...

does anyone have any suggestions? some say one could cannibalize arch and pavilion attachments from another headphone (of another brand) that has mechanical compatibility (with slight DIY adaptation)...does anyone have experience with this? Any idea? Every idea is welcome... I do hate the possibility to pay more then 300 euros for that

thanks in advance for the help

[Timb5881]

Same place mine broke.  I also tried to repair them with h a plastic welder, but alas to no avail.  So I ordered a new L700 mk2 arc and it arrived the other day.  Much better fit and is a more robust design.

[Timb5881]

PS try eBay and see what prices you can on that.

[lupoal]

12 hours ago, Timb5881 said:

PS try eBay and see what prices you can on that.

thks

yes, I've already searched in ebay... almost all potential supplier are form Japan and is roughly  190 - 200 euros + shipment + VAT + custom fee... the final cost is not far from 300 euros that is damn crazy expensive for a piece of hardware like that

[spritzer]

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$.  

Edited December 27, 2024 by spritzer
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