Used headphones – Mjölnir-Audio

Time to split up the special’s page into two so one for headphones and another one for electronics. Here I’ll list my used electrostatic headphones, either they were a part of my personal collection or were a part of some lot I bought so I refurbished them before listing. Feel free to contact me at spritzer@mjolnir-audio.com if you are interested in any item here. I will reply to every mail so if you haven’t received a reply within 24 hours then feel free to send me another email. Email gets lost all the time or is flagged as spam. All prices in US dollars (USD).

Just a quick note about the used headphones. With all electrostatic phones it is possible that they have developed squealing as debris enters the drivers with age. This is something I actively look for and will put in the description (which most sellers would never do) but I might miss some as it can be so subtle. Most of the time this is a minor issue and only comes into play when nothing is playing or on very quiet passages but it’s something I mention if I come across is. Most of the Stax drivers are glued shut so they can’t be cleaned once this has come up. Also the headphone stands the phones sit on are not included.

Here are, what is in my opinion, the best headphones ever made, the Stax SR-007Mk1. This is a late version which were a bit hit or miss but this is one of the good ones. It is in close to perfect condition, headpad nice and tight and the earpads are a bit soft but still perfectly serviceable. There are no more brown parts available so I prefer to only replace parts on these when absolutely necessary. It comes with the original flight case and the outer box, everything in excellent condition

Price: 2650$ plus shipping

Here is a very late production set of SR-009’s in very good condition. I’ve never been a fan of the 009’s but I usually have a couple of them in my collection to try new amp designs and now I simply have too many.

Price: 2500$ plus shipping

Here is a Stax SR-Sigma 404 I just built using a very late production SR-404 as a donor for the drivers and cable. When this set of SR-Sigma’s arrived here it was a mess so they were completely disassembled, they were cleaned (including the damping wool) and then a nice set of 404’s was sacrificed to build them up again. I then topped it all off with a new SR-700Mk2 headpad and thick sheepskin leather earpads as there are no more Sigma units available anywhere. These were designed for the L700Mk2 and they work perfectly here.

In terms of sound this is the ultimate Sigma, large, bold sound with the extension into the bass and treble they always needed. There is no original box for these but they are all falling apart at this point anyway. 🙂

Price: 1790$ plus shipping

Here is a SR-X MK3 which I’ve converted to Pro bias using new old stock drivers and a PC-OCC cable. The SR-X Mk3 Pro are the rarest of all Stax models, rarer than even the 4070 or SR-Omega. In terms of sound, they are what any Grado would hope to be, very neutral yet extended sound with far more bass and control than the normal bias units. Truly one of the best headphones ever made and these sound better than the stock Stax units due to the better cable. They are also fitted with thicker leather earpads to enhance the comfort since the SR-X Mk3’s sure to clamp a bit.

Price: 1450$ plus shipping

Here is a second set of Stax SR-Sigma 404’s. Again a late production SR-404 was used as a donor for the drivers and cable. The Sigma was very nice when it arrived so all taken apart, cleaned and then fitted with the new drivers and cable. Stock headpad and earpads as they were in nice condition. In terms of sound this is the ultimate Sigma, large, bold sound with the extension into the bass and treble they always needed.

Price: 1690$ plus shipping

Here is a mint set of SR-L300’s for sale. I got these by mistake really as I wanted to add the L300 to my collection and accidentally bought two of them. 🙂 These come with the original box and they look good as new.

Price: 375$ plus shipping

Here is a nice Stax Lambda Nova Signature for sale. One of the best headphones Stax ever made and getting rarer and rarer as some of the materials used in these don’t age well. Warm but extended sound, similar in many ways to the SR-Omega as it hails from the same generation. I completely stripped them apart, re-glued the drivers to the baffle, fitted some used but good SR-407 earpads (as there are no more brown pads to be had from Stax) and cleaned up the rest of the set. The headpad has some cracks on the brown surface but again, no more spare parts to be had for these, but it is perfectly serviceable. Sound is perfectly balanced and they come up instantly when plugged in so they will likely last for decades to come.

Price: 700$ plus shipping

Here is a set of SR-404’s I assembled from parts I had in stock. They are stock 404’s except the cable is from the Lambda Signature. Otherwise they sound just like the 404’s and quite lovely at that.

Price: 425$ plus shipping

A Stax SR-L700 Mk1 with upgraded Mk2 forks in very good condition. The Mk2 forks are a welcome update for these and many prefer the Mk1 to the newer Mk2. No original box with this one but they will be very well packaged.

Price: 1050$ plus shipping

Here is a close to new set of SR-407’s in excellent condition. Comes with the original box and sounds excellent. This is really the last gasp for the Lambda series before it all went a bit off a cliff with the new L series.

Price: 700$ plus shipping

Ahh the oddball Lambda, the SR-507. When Stax decided to take the SR-009 headband and cable plus the 404LTD leather earpads, and cram it all on a Lambda shell. They sound pretty different from the 407’s, brighter so a bit more like the old Lambda Signature in some ways. Still an improvement over the modern L700’s. These are pretty sought after now and increasing in price as not many were sold back in the day.

Overall condition is good and they have the same issue as all of these have, the base of the earpads is a bit smaller than it should be so some of the adhesive holding them can be seen. This has no effect on the performance though and they sound just fine.

Price: 800$ plus shipping

This is a Stax SR-X Mk2 fitted with nice leather earpads. The Mk2 was a short lived version of the SR-X before the Mk3 took over and has a nicer, warmer sound to them. This set takes a couple of minutes to charge up before they are fully balanced and they are balanced from then out. It’s not uncommon for older Stax to behave like this.

Price: 160$ plus shipping

Here is something I bought recently but was not quite as it seems. It is marked a PMB500 Electrostatic but as the cable would point to, they are in fact dynamics. These are so rare that I just had to take that chance and pounce on them so with them not being electrostatic, I just want to move them on. For those who don’t know, these were made by PMB and are really the evolution of the Jecklin Float design. Now with full earpads and proper fit these are quite lovely.

I have no idea why these are marked like this with a dynamic driver but it is what it is. I just want to get what I paid for them.

Price: 450$ plus shipping

This is a nice set of late production SR-303’s. The earpads are in good condition but the over the drivers is long gone. The headpad is also functional but has some wear to it. Since there are no more 303/307 units out there I can’t swap it out but it still works just fine. In terms of sound the 303/404 is a high point for the Lambda series, balanced and full sounding with excellent extension.

Price: 350$ plus shipping

Here is a Lambda Nova Classic, one of the best Lambda sets ever. Nice, warm inviting sound which suits nicely with what Stax was doing at the time, namely the SR-Omega.

The earpads and headpad have some age to them but are perfectly functional. Since there are no more replacements I can’t swap them out for anything but black 207 units so I left them in place.

Price: 450$ plus shipping

Here is a second set of SR-507’s, as I called them: “When Stax decided to take the SR-009 headband and cable plus the 404LTD leather earpads, and cram it all on a Lambda shell. ” They sound pretty different from the 407’s, brighter so a bit more like the old Lambda Signature in some ways. Still an improvement over the modern L700’s. These are pretty sought after now and increasing in price as not many were sold back in the day.

This set is in nice condition but suffering from the same issue as all of these, the base of the leather earpads is a bit too small so some of the adhesive holding the earpads can be seen. This has no effect on the sound quality.

Price: 800$ plus shipping

Here is a Stax L-500Mk1 in very nice condition. No orignal box with these but they sound nice and look like new. Only thing non-stock about these are the earpads. I’m not sure where these come from but they might be Vesper units, just not sure. As for the sound, this is one of the better new models Stax sell, a bit on the bright side but far from the 009/X9000 levels.

Price: 525$ plus shipping

This is a late production SR-404, all original with the box as well. The foam inside the earpads has deteriorated so I just cleaned it all out as it does nothing anyway. Not sure what else can be said about the 404’s, they were very misunderstood back in the day but have gained a solid classic status at this point. A good set with a powerful amp can show what the Lambda was capable off well into the 2000’s.

Price: 650$ plus shipping

Here is something very, very rare. In my 20 years of collecting Stax, I’ve only ever seen five of these come up for sale and I’ve bought 4 of them. What we have here is a Stax SR-Lambda Pro with no Stax badges at all, marked Head-Acoustics instead. In fact the only Stax logo at all was on the box as these shipped in a standard Stax Lambda box, completely unmarked except for the unique “HA” serial number. Just the Stax embossed into the Styrofoam. I have no idea how many of these were made, this is the highest serial number of my collection, HA 543 so at least that many.

As can be seen, these don’t have a regular Stax plug but a 5 pin Lemo unit instead. They will come with a custom adapter though so you can use them on any standard Stax amps. In terms of sound, this is a standard Lambda Pro, but it just looks so weird without the Stax markings. No box with these.

Price: 750$ plus shipping

This is a clean and tidy set of SR-303’s. The foam inside the earcups and covering the drivers had degraded so I cleaned it out but otherwise they look great and sound even better. Comes with the original box as well

Price: 550$ plus shipping

Here is a rather nice SR-307 which comes with the original box. I replaced the earpads with new unit so it really is as good as new. Truly one of the last great Stax units with a very nice and balanced sound.

Price: 550$ plus shipping

This is a SR-X Mk3’s in pretty good condition. The drivers are perfectly balanced and charge quickly and I’ve fitted them with some deep real leather earpads to make them more comfortable. One of the best normal bias Stax units ever made.

Price: 280$ plus shipping

Second set of SR-404’s for sale. Very nice condition and with the latest earpads. Truly one of the best electrostatics out there at a sane price.

Price: 450$ plus shipping

Here is a close to mint set of SR-307’s, not really a mark on them. Look and feel as close to new as one can find plus they sound excellent. The last of the great Lambdas before Stax lost their way a bit with the L series. These sound identical to the SR-407’s. Very balanced sound with plenty of extension as well. Comes with the original box as well.

Price: 600$ plus shipping

Here is a Stax SR-207 for sale. Looks to be completely original with minimal wear on them. I use the 207’s as test headphones but I just have too many around that are surplus to requirements. The reason I use these compared to the L300’s for instance, they are far more honest headphones with better frequency response and a more even tone. It’s easy to spot any issues with these and I know of some people who use them for mastering professionally.

Price: 400$ plus shipping

Stax SR-50 electret unit which is pretty rare and only one of two closed electrostatics that actually work ok. This set sounds great and look good for something made in the late 70’s.

Price: 260$ plus shipping

Stax SR-80 Pro electrets. These were called the mini Lambdas back in the day and do sound really nice. This set is in pretty good condition and they make for great test sets since you don’t need a bias supply for them.

Price: 210$ plus shipping

Here is a super rare one, the Stax SR-X mk1 aka. the first Stax to ever have a mesh driver. This one was only out for a couple of years 1970-1972 when it was replaced with the Mk2. That was also short lived as the Mk3 took over in 1975. This one is up there with the SR-1 in terms of rarity but I’m trying to cut down my collection so it must go. Comes with new SR-X earpads and is in very good condition for a set that’s this old.

Price: 350$ plus shipping

SR-3 in perfect condition. This was the first of the “common” Stax headphones so these are relatively easy to find though not in this condition. Great sounding headphones with excellent midrange but the top and bottom end extension is pretty limited compared to more modern units. Still must have been quite special back in 1968

Price: 450$ plus shipping

SR-3New (aka the SR-4) in excellent condition. They look like new and just look at that cable… they never look like that these days.

Price: 400$ plus shipping

I was recently making a SR-Sigma 303 and well… I used the leftover to make these, SR-Sigma drivers and cable in a SR-303 housing. They even have NOS damping behind the drivers so they sound just like a SR-Lambda should, just with a nicer housing. 🙂

Price: 350$ plus shipping

Updated 22.03.2023