Since I just got these, might be time to talk about possibly the rarest stuff Stax ever made.    Let me introduce the SRM-Monitor Mk2 and the SR-Lambda Pro New:

I've only seen a couple of these for sale over the years so very rare indeed.  The headphones are basically the modern version of the Lambda Pro's but not the Spirit/Pro Classic, made later than that.  

The SRM-Monitor has been called the Mk2 but the changes are mostly to the chassis.  Inside there is still a SRM-1 Mk2 and the ED-1 but with different parts.  They are all Pro bias only and notice the extra output on the back.  The volume knob is also similar to the SRM-T1S/W knob and not the SRM-1 Mk2 unit found of the original Monitors.  

I have no idea when these were made but I've heard late 90's and for special customers which wanted to replace their older Lambda Pro sets and SRM-Monitors.  With these here the Lambda collection is almost complete...  

Quote

With these here the Lambda collection is almost complete...  

So what is still missing?

I'd rather not say but I'm missing 3-4 units at this point unless something super, super rare pops up.  

Does anyone have any ideas what kind of damping Stax used in the Sigma?
It looks like some kind of material like cotton wool
but I'm not sure..

I'm thinking of replacing it, but what... it seems like it's not that simple... it looks like mineral wool... and it looks like they manually adjusted the frequency response of each Sigma using this wool... and i can't just take it out and put something else in...

In other news from China, here we have the fake SR-X1:

I've known about these for a while and I finally bought a set as they are so cheap... and very, very rough.  They didn't arrive with any earpads but the knockoff leather X1 pads you can find in Asia do work nicely.  They are clearly not a 1:1 clone and that headband is something really special in terms of being pure and utter garboleum but it was stupid cheap to add it to them.  

Housing is 3D printed and quite badly done but look at that cable... to make the 3D print soft and pliable it looks like an absolute mess.  

Same on this end but the actual plug is nice quality.   Nothing wrong with those pins and the spacing seems just fine.  

Better look at the actual cable used, it is pretty stiff and unwieldy but at least it is 6 parallel cores so the capacitance shouldn't be too bad.  It's too short though at 1.5M or so and who knows what the voltage rating is on that thing.  I did order a couple of extra ones (and some extra housings too) so I'll zap it with some high voltage and see how it holds up.  Anything that can't withstand 1kV AC over an extended time isn't really suitable for this role.  

Better shot if the actual plug, nothing wrong with those pins and it even has the cutout relief for the bias pin which I always skip on my own plugs.  

The driver face and the electrodes are etched aluminum or stainless steel.  Not sure which as I haven't taken them apart yet.  

This headband was clearly an afterthought and that metal bends if you look at the wrong way but it does function... kinda.  

Here we can see the assembly "quality"... or very much lack there of.  The housing does not fit correctly together and you might ask... why was this printed in white and the painted?  Well I paid extra for the paint... but whey when there are excellent black filaments.  Dunno and why not resin print this?  Done right and that is superior to injection molding.  

More of this ace paintjob and the headphones falling apart but nice gold pins there as well.  

As for how they sound... well sound is produced but something is very wrong inside those drivers.  They are far more inefficient than a stock unit and there is audible distortion... quite a bit of it actually.  It gets worse and worse as you push the volume to normal levels for me so I'll have to take them apart and see if the drivers are misaligned.  They are balanced between the channels though and at low level listening... these are not the worst ever.   

Now all of this is pretty terrible but clearly a work in progress and not done by some estat fanatics as one would suspect.  The drivers don't really work (well they do produce some sound) and the quality is downright atrocious but funny enough, that crap cable does have strain reliefs on both ends which the aftermarket Stax cables do not have.  Needless to say, best to stay away from crap too...  

 

 

Dear god, that headband is something else.  It actually looks like someone raided a dumpster for scrap metal and screwed it together to make a headband.  This has got to be a new standard of Chinesium for me.

Yeah, this is shockingly bad.  Why they didn't just adapt the many headbands on the market in China is beyond me.  The CD3000/R10 units are very well made from the right supplier.  

On 3/18/2026 at 6:14 PM, spritzer said:

In other news from China, here we have the fake SR-X1:

I've known about these for a while and I finally bought a set as they are so cheap... and very, very rough.  They didn't arrive with any earpads but the knockoff leather X1 pads you can find in Asia do work nicely.  They are clearly not a 1:1 clone and that headband is something really special in terms of being pure and utter garboleum but it was stupid cheap to add it to them.  

Housing is 3D printed and quite badly done but look at that cable... to make the 3D print soft and pliable it looks like an absolute mess.  

Same on this end but the actual plug is nice quality.   Nothing wrong with those pins and the spacing seems just fine.  

Better look at the actual cable used, it is pretty stiff and unwieldy but at least it is 6 parallel cores so the capacitance shouldn't be too bad.  It's too short though at 1.5M or so and who knows what the voltage rating is on that thing.  I did order a couple of extra ones (and some extra housings too) so I'll zap it with some high voltage and see how it holds up.  Anything that can't withstand 1kV AC over an extended time isn't really suitable for this role.  

Better shot if the actual plug, nothing wrong with those pins and it even has the cutout relief for the bias pin which I always skip on my own plugs.  

The driver face and the electrodes are etched aluminum or stainless steel.  Not sure which as I haven't taken them apart yet.  

This headband was clearly an afterthought and that metal bends if you look at the wrong way but it does function... kinda.  

Here we can see the assembly "quality"... or very much lack there of.  The housing does not fit correctly together and you might ask... why was this printed in white and the painted?  Well I paid extra for the paint... but whey when there are excellent black filaments.  Dunno and why not resin print this?  Done right and that is superior to injection molding.  

More of this ace paintjob and the headphones falling apart but nice gold pins there as well.  

As for how they sound... well sound is produced but something is very wrong inside those drivers.  They are far more inefficient than a stock unit and there is audible distortion... quite a bit of it actually.  It gets worse and worse as you push the volume to normal levels for me so I'll have to take them apart and see if the drivers are misaligned.  They are balanced between the channels though and at low level listening... these are not the worst ever.   

Now all of this is pretty terrible but clearly a work in progress and not done by some estat fanatics as one would suspect.  The drivers don't really work (well they do produce some sound) and the quality is downright atrocious but funny enough, that crap cable does have strain reliefs on both ends which the aftermarket Stax cables do not have.  Needless to say, best to stay away from crap too...  

 

 

Cable looks awfully similar to Cicoil high voltage ribbon cable. 
If they used that (Or much more likely something that is a clone of that) that would actually be highly commendable. That stuff is fantastic for high voltage.

It could be the 20AWG wire but going by the price... I doubt it.  Maybe some Chinese clone 

On 3/19/2026 at 2:14 AM, spritzer said:

In other news from China, here we have the fake SR-X1:

I've known about these for a while and I finally bought a set as they are so cheap... and very, very rough.  They didn't arrive with any earpads but the knockoff leather X1 pads you can find in Asia do work nicely.  They are clearly not a 1:1 clone and that headband is something really special in terms of being pure and utter garboleum but it was stupid cheap to add it to them.  

Housing is 3D printed and quite badly done but look at that cable... to make the 3D print soft and pliable it looks like an absolute mess.  

Same on this end but the actual plug is nice quality.   Nothing wrong with those pins and the spacing seems just fine.  

Better look at the actual cable used, it is pretty stiff and unwieldy but at least it is 6 parallel cores so the capacitance shouldn't be too bad.  It's too short though at 1.5M or so and who knows what the voltage rating is on that thing.  I did order a couple of extra ones (and some extra housings too) so I'll zap it with some high voltage and see how it holds up.  Anything that can't withstand 1kV AC over an extended time isn't really suitable for this role.  

Better shot if the actual plug, nothing wrong with those pins and it even has the cutout relief for the bias pin which I always skip on my own plugs.  

The driver face and the electrodes are etched aluminum or stainless steel.  Not sure which as I haven't taken them apart yet.  

This headband was clearly an afterthought and that metal bends if you look at the wrong way but it does function... kinda.  

Here we can see the assembly "quality"... or very much lack there of.  The housing does not fit correctly together and you might ask... why was this printed in white and the painted?  Well I paid extra for the paint... but whey when there are excellent black filaments.  Dunno and why not resin print this?  Done right and that is superior to injection molding.  

More of this ace paintjob and the headphones falling apart but nice gold pins there as well.  

As for how they sound... well sound is produced but something is very wrong inside those drivers.  They are far more inefficient than a stock unit and there is audible distortion... quite a bit of it actually.  It gets worse and worse as you push the volume to normal levels for me so I'll have to take them apart and see if the drivers are misaligned.  They are balanced between the channels though and at low level listening... these are not the worst ever.   

Now all of this is pretty terrible but clearly a work in progress and not done by some estat fanatics as one would suspect.  The drivers don't really work (well they do produce some sound) and the quality is downright atrocious but funny enough, that crap cable does have strain reliefs on both ends which the aftermarket Stax cables do not have.  Needless to say, best to stay away from crap too...  

 

 

maybe you have Halo Acoustics EH-1 ?

or maybe this one

 

Multiple on both accounts...  

I might have a bit of a hoarding issue... 

Edited March 21Mar 21 by spritzer

On 3/19/2026 at 1:14 AM, spritzer said:

In other news from China, here we have the fake SR-X1:

Can you share any links? Where did you get them?

Sorry, the links I used to buy them are dead but they are floating around on goofish

On 3/22/2026 at 12:39 AM, spritzer said:

Multiple on both accounts...  

I might have a bit of a hoarding issue... 

Do you have a photo of the inside of the black ones?
Are there King Sound drivers inside?

 

i also saw this one

They are a notorious chinese workshop specializing in the production and sale of counterfeit headphones. There are now many workshops in China specialize in producing counterfeit headphones, with zmf, abyss, beyer, and sennheiser being the most affected.

On 3/22/2026 at 4:44 AM, Omega_ELS said:

maybe you have Halo Acoustics EH-1 ?

I know the designers at Halo Acoustics, they are currently expanding into overseas markets and will soon be selling in Europe this year.

On 3/23/2026 at 8:18 PM, Pirx said:

Can you share any links? Where did you get them?

It was sold on goofish, goofish is the largest secondhand trading platform in China.

1 hour ago, Kung said:

I know the designers at Halo Acoustics, they are currently expanding into overseas markets and will soon be selling in Europe this year.

That's excellent news as I liked the latest version I heard, V3.0 I believe.  

The amps are pretty poor though but better than the first version

My friend's L300 pads are melting. Will there be any negative consequences on the sound if he switches to L500 or L700 pads?

 

Also holy crap the build on that X1 clone looks worse than some $20 headphone from the 1990s

The L500 pads are virtually the same, a bit thicker but it won't change much.  Same for the L700 pads but they will both also melt away.  I always use the all leather pads from China now, cheaper and much better quality but you need to get them onto the plastic mounting plate from the original pads... which is a bit of a pain

I'm also interested in Halo Acoustics though I can't find their headphones in stock at Taobao.

I also heard they're making a headphone in the 10,000 RMB range.

If they can fix the QC issues everybody is talking about, then I'm hyped.  I never had issues with my sets but then again... I don't use them all that much.  

Did anybody try these at the NYC meet?  

https://apos.audio/products/sjy-electrostatic-headphones

 

Is this Soltanus drive unit any good? 

https://www.soltanusacoustics.com/electrostatic-headphone-driver-unit-mk-2/