Used headphones
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 and refurbished 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.
The legendary Stax SR-Omega in excellent condition. What can be said about these, they are among the best headphones ever made and a far better than the stuff Stax make now. They claim the X9000 is inspired by the SR-Omega but the sound clearly isn’t. They are as neutral as they come with a huge sound stage. This set is almost fully original, earpads are clearly stock and look like new, they have the original dark brown cable (not the light brown replacement cable) but the arc has been replacement at some point. That means the serial number is long gone as it hasn’t been moved over the new arc. Sadly there was no box with this set but I have a spare SR-009 box which will be included with them. It is the same material as the original boxes plus the foam isn’t falling apart which is always a bonus.
Price: 9995$ plus shipping
Here is a Stax SR-007Mk1 from my favorite range, the early 71xxx. At this point (ca. 2001) it was a mature design and the teething issues of the earlier sets had been fixed. Driver housing had been changed, better materials over all and the improved case too.
This set comes with the original box, original flight case and manual. It’s in lovely condition, sounds great and the earpads and headpad have been swapped out for the new production black parts Stax have now.
Price: 2750$ plus shipping
Sennheiser HE60 aka “Baby Orpheus” from my collection. I’ve fitted a Stax plug to them (with the required 5Mohm ballast resistor) and I just fitted new earpads and headpad so they are as close to new as a 30 year old set can be. Lovely sound and I for one prefer the HE60 to the HE90 as they are far more neutral. One of the nicest sets to have on the head too as they are so light weight. No original box for them as most have fallen apart by now.
Price: 2450$ plus shipping
Here is something rare, a fully working Stax SR-1. It is one of the latter versions of the SR-1 so fully compatible with the Stax normal bias standard. I’d place them from 1964 or so and they are still 100% original. The drivers had wax seals at that time and they are all still there. They charge up instantly and are perfectly balanced This is the first ever Stax set and quite rare at this point.
Price: 2000$ plus shipping
Here is something unusual, an Airbow SR-SC1 aka. the cryo treated Stax SR-404. Now I don’t put any stock into the cryo treatment claims as I believe these were custom made for Airbow by Stax. The amplifiers certainly point to that as there they use the same chassis. Anyway, these are excellent headphones and very rare indeed. A more relaxed and mellow sounding than the usual 404’s, more similar to the 404LE which leads me to think these were custom made for Airbow.
The set looks to have the original earpads and headpad which are both in excellent condition. All of these date to when the SR-404’s had foam covering the drivers so that has all fallen away. The foam on the back of the drivers is in good condition though. It comes with the original box too though it lacks any Airbow markings. It might just have fallen off in the last 20+ years though.
Price: 950$ plus shipping
Now its time for something exceedingly rare, Fontek Research A-4 and C4 energizer. Fontek was run by an ex-Stax employee into the early 2000’s (AFAIK) when he passed away. The company folded then but these are rather unique as they use two electret drivers per channel, stacked inside the earcups. The energizer is so big as it contains 4 transformers. Utterly bonkers design but so very, very rare. I’ve been following the market in Japan for two decades now and only a handful of these units have come up for sale in that time.
When I got this set, the energizer was missing the unique speaker connector these use and just had loose wires running from the back of it. I removed that and fitted some regular speaker binding posts as the stock plugs are impossible to find at this point. The earphones had the stock earpads still on them but they had completely broken down. I removed them and fitted my regular SR-X leather earpads.
Price: 795$ plus shipping
Here is the holy grail of the Lambdas, a set of the original SR-Lambda normal bias and an early one at that. These are getting thin on the ground and the prices match that demand as it is one of the best sounding Stax sets ever made. Very balanced sound signature which does nothing wrong really. Also very comfortable for long listening sessions. The left channel takes about a minute to charge up compared to the right hand side but the difference when it is happening is quite mild. After that they are fully balanced and sound lovely.
This set arrived in quite good condition and looks fully original. The earpads have seen better days but I treated them and put in the close inserts as the foam is long gone. I made some small repairs to the headband so now they function as they should. Overall a nice set of these very rare sets. They come with the Styrofoam box but not the outer paper sleeve.
Price: 695$ plus shipping
Here is a lovely set of the legendary normal bias Stax SR-Lambda. The original Lambda and an attempt to take the SR-Sigma and make something sensible out of it. It really is in a class of its own in terms of sound, very balanced with great presence while trading a bit of extension at the extremes.
This set is in lovely condition given its age and looks to be fully original. I did open up the earcups to check out the drivers, clean out the crumbling foam and remove the protection silistors as they don’t age well. The mineral wool covering the back of the drivers isn’t perfect but it does its job. This one comes with the original styrofoam part of the box but not the outer cardboard part.
Price: 650$ plus shipping
This is a late production SR-404 which are as good as new. I can’t see any marks on them and they come with the inner box and a manual. The SR-404’s are one of the best Lambdas ever made, very balanced sounding with great extension.
Price: 650$ plus shipping
Here is a Stax SR-007Mk2, Mk2.9 version. These are in perfect condition and I also performed the port mod so they sound like they should. The Mk2’s and A models are identical, it was just the color difference that set them apart until Stax made a limited run of black 007A models. In terms of sound, with the port mod, these sound very similar to a late production Mk1 unit. It comes with both the flight case and the outer box.
Price: 2100$ plus shipping
Yet another SR-007A of the Mk2.9 version. These were the second to last 007’s Stax ever made and the version I prefer over all. Like all my other sets, these have had the port mod performed and they come with the flight case and manual, but no outer box. They look and feel like new and sound excellent.
Price: 1900$ plus shipping
Here is a Stax SR-Sigma Pro in rather nice condition and all original. With the release of the Lambda Signature in 1987 the Sigma’s were finally updated to Pro bias so these have the PC-OCC cable, 1um drivers and brown headpad of the Lambda Signature plus the main housing shares the same dark brown color of the Signature. In terms of sound the Sigma’s have always been unique but the normal bias units lacked power, which the Sigma Pro’s delivered. A true speaker-like sound signature and while being rather big, light and comfortable on the head.
These sound just perfect off a powerful amplifier and only small cosmetic issues with them. The foam inside the earpads is long gone as with all of the Sigma’s and the cable has two splits (where the two channels are separating from each other) but the splits don’t seem to be increasing in size.
Price: 1500$ 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: 1600$ plus shipping
After more than two decades of collecting Stax items… not much surprises me anymore but these certainly did. This is a Lambda Signature and have been fitted with black replacement earpads. The weird part is the cable… it’s only roughly 1M in length. Normal Stax cables are 2.5M but this is not some hackjob… this is a stock cable from Stax so clearly a custom order. The regular moldings are on both ends and the only difference to the regular cable are silver pins, not gold ones as they should be on a PC-OCC cable. This set is in good condition, I removed the crumbling foam from inside the earcups and the foam is also gone from the drivers but overall they are great.
Price: 550$ 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: 1500$ plus shipping
This is a Stax SR-XMk3 that I’ve completely rebuilt with new old stock SR-XMk3 Pro bias driver and a new PC-OCC cable. This turns them into the much vaunted SR-X Mk3 Pro’s, the rarest of all Stax models. World class monitoring headphones which are as transparent as they come without the overly forward nature of something like the current SR-X9000. The cable entry on this set was trashed when I got it so I upgraded to nice Teflon strain reliefs that will last longer and protect the cable better. It’s not as blue in real life, the flash on the camera just makes it appear so. Other than that they are in very good condition and fitted with my own leather earpads to increase the comfort.
Price: 1300$ 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: 350$ plus shipping
This is a set of SR-Lambda Pro’s which arrived in a rather sorry state. The sound was excellent though, balanced and extended so they had to be saved. Earpads and the entire arc were trash so the whole thing was cleaned on the outside (it’s not a good idea to disturb the earcups on these as it changes how they should sound), the cable cleaned and treated, new earpads fitted and a used arc from a SR-202 fitted. Very nice sounding set of headphones which can now go on to play for another 40 years or so.
Price: 350$ 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: 375$ plus shipping
This is a lovely Stax SR-Lambda Pro which is in close to mint condition. Aside from the foam inside the earpads being long gone, they look really nice and sound perfect. The Lambda Pro was the first set featuring Pro bias back in 1982. It has a lot in common with the normal bias SR-Lambda but the sound is a bit different. No original box with these.
Price: 600$ plus shipping
Here is a stock Stax SR-L300 in mint condition. These have now been superseded by the SR-X1 but L300’s are a much more comfortable set of headphones and have a much larger soundstage. They come with the box as pictured.
Price: 380$ 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: 750$ plus shipping
Here is a near mint Stax SR-207 with the original box. These are still to me the best entry level set Stax have ever made, easily surpassing the modern SR-X1 in every way. I still use my first 207’s nearly every day to test every amp I build/modify as they are so brutally honest and never let me down.
Price: 400$ plus shipping
Ahh the great Stax SR-Lambda Nova Signature. Excellent warm sound with plenty of body, similar in many ways to its contemporary the SR-Omega. Being 30 years old at this point though, they are not holding up all that well so I’ve been buying up those that I can save and fully refurbishing them. That includes stripping them down, even removing the driver from the protection grille, cleaning off all the glue and then rebuilding them back up again.
This set has been fitted with new, black earpads (as that’s the only thing Stax will sell us) but the headpad was 100% functional so I left it in place. The top has the fake leather flaking off but the underside is nice so it still works just fine.
Price: 650$ plus shipping
Here is something rare, a Stax SR-Lambda Pro Classic. They were the European version of the Japanese only Stax Spirit headphones but slightly different sounding. These have had the headpad changed out at some point so the branding went along with it (it was printed on top of the headpad) . I cleaned out the foam inside the earcups when I got them and the foam inside the earcups is gone as well. I find these to be smoother than the stock Lambda Pro and more open sounding but still have slight edge to them. Very enjoyable headphones for a wide variety of music styles.
Price: 410$ plus shipping
Here is a Lambda Nova Basic which arrived in a sorry state. The arc was in pieces and somebody had reattached the drivers to the baffles but done it badly. The drivers sounded just fine though so I fixed it and cleaned up the set in general. They were then fitted with a new SR-L300 arc so they look and feel close to new. As for the sound, these are very much of the Lambda Nova generation so warmer than other Lambdas but not overly so. They just sound lovely and are forgiving, especially in the top end.
Price: 320$ plus shipping
A set of SR-303’s in nice condition and all original. This is the later production version with silver protection screens for the drivers. Stock earpads and headpad in place though the foam inside the earpads has disintegrated as they all do at this point. Very nice set of headphones that would have been a shame to break up to upgrade some Sigma’s.
Price: 375$ plus shipping
Here is a rather nice set of Stax SR-Lambda Professional’s, all original and even the foam inside the earcups is mostly intact. These are warmer sounding than the normal Stax Lambda units and pair really well with the SRM-1 Mk2 amps.
Price: 500$ 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
This is a nice set of Stax SR-X Mk3’s that are perfectly balanced sounding and come up to sound quickly. They have been fitted with new leather earpads.
Price: 230$ plus shipping
This is a mint set of SR-L300’s but I’ve been modifying these to try and clean up the sound a bit. Small mods but yeah, these are an improvement over the stock units and something I’m going to look into further. They come with the original box.
Price: 325$ plus shipping
This is a very nice set of Stax L500 Mk1’s that come with the original box and instructions manual. The earpads on these don’t last all that long so I swapped them out for aftermarket leather units.
Price: 550$ 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
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: 650$ plus shipping
Here is a Stax SR-L500 Mk1 in very nice condition and looks like new. Earpads have been replaced with the non-oem leather L700 earpads. As for the sound, this is one of the better models Stax sell, a bit on the bright side but far from the 009/X9000 levels. I prefer the L500 units to the L700’s as they trade some top end for a fuller sound. No original box with these.
Price: 520$ plus shipping
Here is a Stax SR-X Mk3 normal bias unit in rather nice condition. These are some of the nicest I’ve seen in years and even have the stock earpads on them. They have started to flake but they are so easy to replace later on that I just left them on. One of the best headphones Stax ever made, very honest sounding as they were designed for monitor use. This set has balanced drivers which come up to song quickly.
Price: 240$ 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: 550$ plus shipping
Here is a set of Koss ESP/95X (aka the ESP/950) that I’ve modified to enhance their performance and make them easier to live with. First off, the cable has been replaced with a King Sound unit as these work well with the stock opening and are fully Stax compatible. Second I’ve removed most of the stock damping to clean up the sound and finally some nice leather earpads are fitted. In stock form the ESP/95X is very much mehhhh and a lot of that is down to the amp, the earpads and the damping. Now none of that is an issue and these really shine now. Very much comparable to the best of the Stax Lambdas or L series and give a warm, full sound with plenty of extension.
Price: 575$ 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: 600$ 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: 350$ 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: 260$ plus shipping
Here is a mint Stax SRS-002 system, with the box. These are excellent little portable units and I’d take them over the Shure KSE systems any day. Far more neutral and powerful.
Price: 375$ plus shipping
A Stax SR-207 with its original box. These are to this day my go to test headphones, every amp I build or refurbish is first tested on a set of 207’s as they tell me instantly if something is wrong. Neutral and honest headphones across the spectrum and they scale very well with better amps. They have also seen extensive use in studios. This set is in good condition over all except the headpad has been cleaned rather aggressively at some point so it is a bit floppy. It works perfectly though.
Price: 360$ 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: 220$ 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: 175$ 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: 350$ 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: 300$ plus shipping
SR-303’s with the original box and in 100% original condition. The foam covering the drivers inside the earpads has perished as they all do, the earpads have cracks forming all over but they are still perfectly serviceable and the headpad is also perished a little bit but they are all perfectly serviceable. Same sound as the SR-404 for less money so great headphones for a first system.
Price: 350$ plus shipping
Here we have a Stax SR-3New that is fully original except the cable has been replaced with the far superior ribbon cable. The set works perfectly and comes up on song in second or less.
Price: 225$ plus shipping
A completely stock SR-L300 in very nice condition. I’ve always been meaning to do some projects with these so I keep buying them but alas, nothing has come of it yet. This set is close to new in condition and comes with the original box as well.
Price: 295$ plus shipping
Here is a late production SR-404’s which were destined to be harvested for parts but given there is nothing that needs these drivers now, they get a stay of execution. Perfectly balanced drivers with excellent extension so they truly sound the best of the Lambdas. No box with these.
Price: 425$ plus shipping
This is a Stax SR-3 New in great condition with the original box and a few interesting documents in the box, such as the original sales receipt. Like so many of these older normal bias sets, it takes about two minutes for it to charge up after plugging in but it is fully balanced while doing so and stays like that. This is a great way to try the vintage Stax sound and a lovely set at that. Even the original earpads are nice and supple.
Price: 215$ plus shipping
This is a rather early set of SR-404’s in original condition. The foam inside the earcups was all perished and the same for the foam inside the earcups, I removed all of it and cleaned them up. They have the original earpads and headpad though which are perishing a bit but they are still functional. There are no more brown spare parts for these so I only replace now when I absolutely have to. No box with these either.
Price: 300$ plus shipping
This is a set of Stax SR-Lambda Signature which is fully original except the headband arrived broken so I’ve swapped it with the modern Stax 404/407 Signature replacement. The rest is fully stock and they sound great, that super thing 1um diaphragm being very fast sounding but with decent extension. These will really open up on good amplifiers and sound great for something close to 40 years old. No original box with these I’m afraid.
Price: 550$ plus shipping
This is a very early Stax SR-202 in nice condition. Being the entry level Stax, they don’t always lead an easy life but this one is just lovely and looks like new. These come from the age where a layer of foam covered the drivers and that has naturally broken down but the earpads are in lovely shape though. Very good sound from these, maybe not as refined as the 303/404’s very close in sound.
Price: 285$ plus shipping
The Stax SR-207 in nice condition, fitted with a new SR-L300 arc. Still the best entry level set Stax have ever made, very balanced sound and very revealing.
Price: 320$ plus shipping
Here is a set of SR-303’s that I got for cheap and cleaned up. Same drivers as the SR-404 but with the thinner PC-OCC cable but they do sound great. The earpads on these were just beyond saving so I fitted a new black set from Stax (as that’s the only color we can get) but the headpad was worn but functional.
Price: 245$ plus shipping
Lambda Nova Basic, the successor of the Lambda Spirit as the entry level Stax set of the day. They carried over a similar driver structure but fitted with the then new headband design. Similar to the other Nova series the sound is warmer and more forgiving than the older Lambdas. This set is in lovely condition, the foam over the driver face is long gone but otherwise they look great.
Price: 330$ plus shipping
This is an all original set of Stax SR-5 in nice condition. The SR-5 was the last of the early Stax sets and in production for well over 15 years and really the pinnacle of that driver design. The same driver was used in the SR-X Mk3, SR-Gamma and SR-Alpha. The pro bias variant was then used in the SR-X Mk3 Pro. Very balanced and nice sounding set of headphones and they scale really well with better amps feeding them. They also charge up instantly so no channel imbalance when first plugging them in.
Price: 260$ plus shipping
Here we have a very good condition Stax New SR-3 aka the SR-3N. This was the last of last of the Stax models which were completely based on the older SR-1 design, same headband and everything. Excellent midrange and they sound really good for something released in the early 70’s.
The earpads on these are a bit flat but still perfectly serviceable. When first plugged in there is a bit of a channel imbalance but they are back to normal in less than 60 seconds or so.
Price: 230$ plus shipping
Updated 20.1.2025