STAX Discussion for STAX and Other Electrostatics

Mostly STAX and related equipment, but any other Electrostatic phones and discussion welcome. By related equipment, amps and energizers to run the power-hungry beasts.


I just got outbid on eBay on a pair of lightly-used Stax SR-L700s. The bidding was languishing in the mid $600 range, then 20 minutes to go went to $730. With 8 minutes to go it was at $740 and sat there. Not a particularly good sign. I clicked in at $776 in the last 5 seconds, but my bid never made it in the final flurry.

Someone got a great deal for $830. Most very slightly used Stax SR-L700 phones go for about $1100. New $1400. For me, If I’m getting much over $800, I might as well get them new.

All it takes is two bidders. Don’t know where it would have ended.


Thanks @penntac for this new topic. I have always wanted to check out the World of Stax

I am anxious to hear pros and cons.


Well I think we have a few Stax partisans here. @EdAInWestOC seems to know and like Stax well enough, and @spritzer lurks here sometimes and may possibly drawn out. He has Mjölnir Audio and makes and mods some nice electrostatic headphone amps.

I recently bought an older STAX SRM-T1S tube amp that he modified and recapped, and I’m very much enjoying it. This is one of the earlier of the main line of Stax tube headphone amps, and features both standard and Pro bias. My headphones are older and have standard bias, so I need that. Since about the 90’s it’s all Pro bias. (higher, 580 volt bias voltage).

I understand that almost all of the tube amps since that time are quite similar, with dual FETs in the first stage and 6FQ7 triode tubes in the second stage. The very top end newest models are different. @spritzer says that the design is limited (flawed) by some honking big resistors that soak up power from the tubes, and he put in a re-designed setup similar to his Mjölnir amps. I failed to copy down the actual discussion that was on his website describing the mod, and he took that down when I bought the amp.

I think I need some help from the STAX Mafia here, @spritzer.
Oh wait, there is no Mafia.

All I really know is it makes my old SR5N phones sound better than they ever have.


Grrr. I thought I’d try and get clever with the Wayback Machine, but the page I want wasn’t archived.

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I really should just pull the trigger on adding an electrostatic option to my primary rig. I keep putting it off as the setup I would nominally go for just takes up more space than I currently have to dedicate to a single headphone. And the more compact options just haven’t proven to be sufficiently compelling to bother with.

I was kind of hoping that the iFi Pro iESL would change that … but it was quite underwhelming and just another incidence of an energizer (rather than an actual amplifier) completely failing to do the cans justice.

Have you thought about Mjölnir’s Octave 3 amp? Looks like it might work for you. From their website:

Here is one in the same vein as the SRD-7 below though not a transformer but rather an electrostatic power amp. So many of us have excellent amps which could act as preamps so something like this has been requested frequently over the years. It can be used with most headphone amplifiers, preamps or even passive preamps. It is an Octave V2 but with no volume control and only the XLR input sockets on the back. It can also be used single ended with either XLR to RCA adapters or a special cable.

This is a nice and simple way for anybody with a good stereo or dynamic headphone system who wants to try electrostatics.



I can see the appeal of it, and it’d fulfill the “compact” criteria, but absent the ability to audition it - it isn’t really an option. Especially as a) I cannot find a single review of it, nor the amp it is based on and b) it would be tied to a multi-thousand dollar headphone purchase.

I appreciate the suggestion, though.


I just can’t get past the aesthetics of Stax… I liked the look of the Koss model on Massdrop, but the problems @Torq brings up, plus like @pwjazz stated, those particular ones can be found cheaper online. Maybe one day…

Well, I have the old SR-5N, they’re round. And the flagship ones are round. And there are a number of other round ones you can get. I’m not looking for fashion a la Beats. I’d rather have the flagship, but the same or very close tech goes into the traditional Lambda shape SR-L700s.

The real aesthetic is in the listening.

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the SR-009 is pretty but quite expensive

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I don’t think my wife would appreciate me coming home with those lol

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I got my first amazing headphones (HD800) from a guy who is been in this hobby for 30 years or more. In those years he had and tried every existing audiophile headphones and was downsizing his collection of headphones, amps and dacs to buy what he called “the best headphones” he ever try, the Abyss 1226 Phi. and also because most of the equipment was never used or not used enough.
My point is( after a long introduction) he was keeping the best and just the best he had and a STAX was among them!! I think I see in my future a space and a saving for a Stax headphones and amp ,at least to give them a chance since I’m more curious about them every time. He was keeping the Utopias , the Abyss and the Stax I300/323 amp.


Congratulations the HD800 is a great set of cans.

Thanks , they are!!!

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