Why aren't many solid-state based electrostatic amplifiers, specially for headphones?

[solderdude]

https://clarityfidelity.blogspot.com/2016/05/audeze-lcd-2-fazor-over-ear-headphones.html?m=1
lcd2f

This is not a stat but planar magnetic. To me it doesn't have the typical properties of a real stat either.

 

[KeithPhantom]

This is not a stat but planar magnetic. To me it doesn't have the typical properties of a real stat either.

We know the LCD-2 isn't a stat, but it's distortion is really low for a mechanical device.

 

[preload]

I had the SR-009 for a few years. They definitely sounded better on a Woo WES tube amp compared to the SS Stax 727. It could have just been that the SS implementation on the Stax was poor. But strangely, I preferred the 727 when driving the SR-007mk1. There are a few sr-009 amp shootout reviews on the web if you trust that kind of stuff. As someone mentioned, the Kevin Gilmore stuff was supposedly pretty good. I never had a chance to try it out though.

 

[waltzingbear]

try looking at https://mjolnir-audio.com/products/. His work has seemed to be of good quality. No personal experience.

But, yea, its a very small niche market of a small niche market.

I've incorporated some of Kevin's ideas into my SRM1 MK2 and they have improved the performance.
Using Stax earspeakers since 1973

 

[T3RIAD]

I had the SR-009 for a few years. They definitely sounded better on a Woo WES tube amp compared to the SS Stax 727. It could have just been that the SS implementation on the Stax was poor. But strangely, I preferred the 727 when driving the SR-007mk1. There are a few sr-009 amp shootout reviews on the web if you trust that kind of stuff. As someone mentioned, the Kevin Gilmore stuff was supposedly pretty good. I never had a chance to try it out though.

The 727 is generally regarded as Stax's worst SS amp. The 353x is supposed to be better, or you can do a global feedback mod to the 727 that supposedly fixes it.

I too wish there were more measurements of e-stat amps. I think Amir said he might do them someday

 

[phoenixdogfan]

It's a small niche market so there's very little demand for someone to hook up one of their expensive audio analyzers to one.

AFIK, the only good alternatives to Stax's own amps are the Kevin Gilmore designs. IIRC there are several new solid state designs he's done in recent years.

Personally though, with the lack of credible data, I'd just get a SRM-353X.

IFI also makes something. Zeos uses it. Myself, I dunno, seems to me electrostatics are not worth the additional tariff, and the ridiculous cost of headphone energizer/amps.

 

[maverickronin]

Myself, I dunno, seems to me electrostatics are not worth the additional tariff, and the ridiculous cost of headphone energizer/amps.

There's just nothing else is as clean and clear though.

For amps, the SRM-252S is also a good option if you don't need to listen crazy loud. If you wait around for good deals on ebay you can get a good pair of Lambdas and an amp for less than a lot of flagship dynamics or planars.

The real downside is that they're fragile. The transducers themselves are susceptible to damage if used in a high humidity environment and good luck trying to to find off the shelf wire to replace the cable with when the awful Stax ribbon cable inevitably gets damaged of wears out.

After 50 or so years Stax finally just started selling models with replaceable cables.

The Koss 950s are prone to incessant squealing, presumably caused by ingress of dust. Koss will replace them for free as often as you need, but who knows how much longer they'll be around.

I also have a probably 25+ year old SRM-T1S with with more than 100V of offset which I really need to get around to fixing too.

 

[bigjacko]

I have Koss x massdrop ESP/95X, the frist two got squeal problem, the third one still has a bit sometimes but I found not touching the driver solves the squeal problem. What I found was if I don't touch the foam protecting the driver with my ear, there is no squeal.

 

[srsxmi]

I have seen that koss ESP9/X energizer claim to has thd+n 0.001%, stax only have 0.01%. But most people still say stax energizer sound better which I don't understand why, anyone knows why?

I do agree with the subjective impression - the ESP9/X does sound much better with an SRM-353x than its own energizer. That convinced me to buy a Stax SR-007 mk2 and SRM-700T.

I wish we had measurements on the electrostats like we do w/my topping d/a90, etc..... TBD.

 

[levimax]

Are electrostatic headphones safe? Seems like very high voltage to be so close to your head / brain.

 

[srsxmi]

Are electrostatic headphones safe? Seems like very high voltage to be so close to your head / brain.

Yes, Stax says just don't listen too them with wet/damp hair and don't use them in high humidity environments.

 

[maverickronin]

Yes, Stax says just don't listen too them with wet/damp hair and don't use them in high humidity environments.

And even that is only really only a danger to the headphones. Unless you're trying to actively trying to electrocute yourself, you won't.

If you are, well even a 9 volt battery can do you in.

 

[srsxmi]

And even that is only really only a danger to the headphones. Unless you're trying to actively trying to electrocute yourself, you won't.

Right, that's the message - its warning about the equipment. One should not use them outside in northern CA right now either - I expect the caustic ash in the air might cause problems.

 

[xykreinov]

I have seen that koss ESP9/X energizer claim to has thd+n 0.001%, stax only have 0.01%. But most people still say stax energizer sound better which I don't understand why, anyone knows why?

Misleading numbers from Koss. An old Stax energizer was just measured to have less distortion: https://www.audiosciencereview.com/...-headphone-amplifier-review-comparison.17161/
However, not by much. Koss' energizer still does a decent job. It's totally respectable, given how much cheaper it is. The main thing your missing with the ESP9/X energizer, compared to a Stax energizer, is power.