What DIY Amps are available for Stax?

The only two that I am aware of are the KGSSHV, and the Blue Hawaii. Unfortunately, it appears that Kevin Gilmore's website was taken down when he retired from Northwestern, and that had the BOMs and schematics for both of those amps. I'm also unsure if it's even possible to get boards for these amps anymore.


Are any fellow Stax enthusiasts able to shed some light on this?
 
... a couple of sites I had seen in the past:

"Auridux" --> AURIDUX, a directly coupled Stax Electrostatic Headphone Tube Amplifier

"Stax SRX" schematic --> Electrostatic Headphones Amps

I had built this SRX and "it made some fine music";
not very difficult to build, if you've done some diy with vacuum tubes
(but after all I dismantled it, because the oscilloscope traces showed a large unbalance between the two signals from the phase splitter (I think this setup is called "Van Scoyoc" - it could be that I was just not measuring correctly, since I found out much later that the probe may influence the signal and you need to compensate for this...)


_
 
not a rocket science, one needs up to 500-1000x gain. (phono-pre terrritory, therefore quality parts matter )
total required gain- more or less depending on your sounds sources.
using a 2vrms max dac, 500-600x is enough volume wise
http://peteslab.blogspot.com/2015/11/stax-2a3-se-amplifier.html

stax hp are very true to sound, expect no boomy bass like beyers... you may end turning up your bass eq.
hovewer, found a way how to make them bassboom. (redneck garage mod done between earpad & driver case)
 
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I don't own a Stax but if I did, it would be the 009s with a Stax DIY SRM-T2. :)

The ultimate DIY? A Stax SRM-T2! - Do It Yourself - www.Head-Case.org

Is there a schematic? That thread on head case links to many files that are no longer available. I googled and saw some pictures of stuffed circuit boards, and it appears to be an otl push-pull design, with op amps, guessing to be constant current source feeding the tubes. Bi-polar regulated power supply, it seems.

I am not brave enough to buy a 009 without extensive Stax experience. But I think I can start with a L300 or L500.
 
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it was inspiration for me, but really its just 2 basic stages. it cant go simpler than that.

however over time i did some improvements..see my blog.
so easy, with gains close to phono pre.

I read your update. I guess for new builds, you have changed your suggestion to using LL1677 (for JJ 2A3-40) instead of LL1660? I may just do that as I have a quad of JJ 300B sitting idle, and those JJ 2A3-40s basically are just JJ 300B tubes with 2.5V filaments.
 
i still use the ll1660/18ma :)
i do not have 1677, probably never will since i switch sovteks and jj. at moment. been also thinking about eml 2a3 meshes....one day...

as i can tell, one of biggest improvements were the gyrators for drivers. latest update really pops the microdetails. (jfet+ledpv bias fet)
ecc83+ra was too much muffled. it seems the 2a3 capacitance was interfering too much.

i found out that stax you can add some bass. i wrote a more at headfi.
good or bad seal makes bass weak, but if you find the spot in between.....microfoam selfadhesive roll for sealing windows :checked:
 
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I just bought some older Stax Lambda headphones with the SRD-6 energizer. What are the limitations of the energizer? Will it work with the common class D bridged amps and unloaded tube amps without any risks of damaging the amps? It works really well with my Marantz integrated amplifier, but I need something smaller - best if also equipped with a headphone out.

Would a high voltage swing preamp work as well? As far as I understand, only voltage with very low current is needed. I want to keep the energizer for the Stax and also have an output for dynamic headphones in one common amp/preamp. Any thoughts?