[bobkatz]

Interesting do you notice much improvement pro bias (580 volt) vs boosted 1100v? Just curious

Not sure I understand your equating bias and drive voltage. I'm always using pro bias, that's a given at this point in the Stax world. The ability to drive 1000V+ RMS before clipping is very helpful in my opinion. I have a pair of Pro drivers in an SR5 case that someone put together for me years ago. They are MUCH more efficient than the 007, about 6 to 10 dB hotter for the same drive voltage. So at some point Stax made far more efficient pro drivers. Higher drive voltage is very useful these days. Weak drive capability is the weakness of all the Stax tube and solid state units, the impetus for the KGSS I reckon.

 

[gammi]

those 10khz square waves still look pretty decent.

a purpose built transformer with bifilar primary and secondary would result in a much better transformer.
too bad diy parts are not available.

I unfortunately just had to DIY the non-DIY transformer in my old Sansui AU-X11 amp when it blew a thermal fuse. Not fun
Miraculously somehow closed back up cleanly.

 

[aokman]

"bifilar primary and secondary" - LUNDAHL makes those on special order, also sectioned to provide high isolation voltage, from what I know...

It is funny that Lundahl directly link to the project of using 1630s for electostats but haven’t tried to make something bespoke and designed for the application…

 

[gammi]

It is funny that Lundahl directly link to the project of using 1630s for electostats but haven’t tried to make something bespoke and designed for the application…

I wonder why STAX ever stopped making transformer boxes. Seems to be a bad business decision to block out the entire market of people who don't want to buy a new amp just to use only with their headphones. (Which is most people)

 

[timb5881]

I wonder why STAX ever stopped making transformer boxes. Seems to be a bad business decision to block out the entire market of people who don't want to buy a new amp just to use only with their headphones. (Which is most people)

My guess was lack of sales drove their SRD series out of production

 

[Lindholdt]

I'm considering listening to some Stax headphones to hear what they have to offer. I have the option to try a set of SR-007mk2.
Are these somewhat representative of what Stax headphones can do, or are they pretty much outdated at this point?
Is there a better option I should try at this price range? I might be able to listen to a set of SR-L700MKII, would that be better? They are more expensive, though.

 

[padam]

The SR-007 Mk2 is an outlier (or rather was, since it has just been discontinued...), not having the thinner, brighter, clarity-focused nature of modern Stax.
So yes, very much outdated in that regard. Still not as much as an Mk1, which is the youngest Stax I use regularly, is still up to 25 years old at this point.
The SR-X Mk3 is nearly half a century old at this point - still very much relevant, impressing me every time I take it out.
Main point is: 'outdated' just doesn't quite exist the same way as with other brands.

Sarcasm aside, each has a completely different representation of sound that you might prefer, you may need to do some more research in these massive threads rather than taking blind advice by just relying on a few replies.
(There are also caveats regarding amplification, or some simple mods to plug in the port on the SR-007 Mk2 or seal the earpads on the L700 Mk2, etc.)

 

[aokman]

I wonder why STAX ever stopped making transformer boxes. Seems to be a bad business decision to block out the entire market of people who don't want to buy a new amp just to use only with their headphones. (Which is most people)

From my experiences of trying to sell my SRM-1 without headphones and people saying im selling it incomplete…. 99% of people have NFI what STAX is let alone a transformer box…

 

[icnaiwhimor1975]

99% of people have NFI what STAX

so much the better for those who have them

 

[bobkatz]

I'm considering listening to some Stax headphones to hear what they have to offer. I have the option to try a set of SR-007mk2.
Are these somewhat representative of what Stax headphones can do, or are they pretty much outdated at this point?
Is there a better option I should try at this price range? I might be able to listen to a set of SR-L700MKII, would that be better? They are more expensive, though.

I am absolutely not a fan of the Lambda-style Stax headphones, I was always uncomfortable with the imaging and even the tonal response. The circumaural style Stax is the only way to go in my opinion. The 007 Mk2 in my opinion sounds much more accurate than the 009, The 009 is way too bright. Even then, the 007 is bright and a bit thin in the bottom, but far more neutral than any previous circumaural model Stax. After I got my Audeze CRBN headphones I put my 007 Stax in its case and it sat there for about 2 years. It was already at least 10 years old. But I recently pulled out the 007 to revisit the phone and I find pleasantly that it seems to have aged very nicely just sitting in the box! Yeah, it could be my imagination, but I think that the diaphragm tension may have loosened a bit and so the bass response is much more extended than I remember it and the high end has softened in a nice way. It also has the Spritzer port seal mod. I'm very impressed now, the "aged" 007 sounds really nice!

I have EQs that I have implemented for each phone that I have to subjectively match my calibrated mastering loudspeakers. I now use an RME ADI-2 FS DAC for EQ and headphone drive. The line output feeds my custom transformer-based Stat amp and the headphone outputs feed the dynamic phones. The RME is so smart that when you plug in the dynamic phone it automatically switches to the eq and balance settings for that phone, and when you unplug the dynamic phone it switches to the last EQ setting that I used for the Stats. So comparing the Stat to the dynamic is painless.

The EQ I have used for the 007 has a bass boost (among other bands) and the 007 takes that boost very comfortably without any overload, as long as you are using a high headroom amplifier like my KGSS Carbon or my new transformer-based Stat amp that I built. If I give the equalized Audeze CRBN a 10 grade, I can now happily give the equalized Stax 007 Mk2 a 9.5! At that point it only lacks a bit in soundstage width and height compared to the CRBN, but tonally after EQ the two are almost on a par. On the same grading scale, my equalized Audeze LCD-5 gets a 9, so things are very nice at casa Katz. I have two CRBNs, one 007 Stax and one LCD-5 and with EQ I consider all 4 phones to be reference-quality!

 

[bobkatz]

I am absolutely not a fan of the Lambda-style Stax headphones, I was always uncomfortable with the imaging and even the tonal response. The circumaural style Stax is the only way to go in my opinion. The 007 Mk2 in my opinion sounds much more accurate than the 009, The 009 is way too bright. Even then, the 007 is bright and a bit thin in the bottom, but far more neutral than any previous circumaural model Stax. After I got my Audeze CRBN headphones I put my 007 Stax in its case and it sat there for about 2 years. It was already at least 10 years old. But I recently pulled out the 007 to revisit the phone and I find pleasantly that it seems to have aged very nicely just sitting in the box! Yeah, it could be my imagination, but I think that the diaphragm tension may have loosened a bit and so the bass response is much more extended than I remember it and the high end has softened in a nice way. It also has the Spritzer port seal mod. I'm very impressed now, the "aged" 007 sounds really nice!

I have EQs that I have implemented for each phone that I have to subjectively match my calibrated mastering loudspeakers. I now use an RME ADI-2 FS DAC for EQ and headphone drive. The line output feeds my custom transformer-based Stat amp and the headphone outputs feed the dynamic phones. The RME is so smart that when you plug in the dynamic phone it automatically switches to the eq and balance settings for that phone, and when you unplug the dynamic phone it switches to the last EQ setting that I used for the Stats. So comparing the Stat to the dynamic is painless.

The EQ I have used for the 007 has a bass boost (among other bands) and the 007 takes that boost very comfortably without any overload, as long as you are using a high headroom amplifier like my KGSS Carbon or my new transformer-based Stat amp that I built. If I give the equalized Audeze CRBN a 10 grade, I can now happily give the equalized Stax 007 Mk2 a 9.5! At that point it only lacks a bit in soundstage width and height compared to the CRBN, but tonally after EQ the two are almost on a par. On the same grading scale, my equalized Audeze LCD-5 gets a 9, so things are very nice at casa Katz. I have two CRBNs, one 007 Stax and one LCD-5 and with EQ I consider all 4 phones to be reference-quality!

The older you go in the Circumaural Stax, the brighter they were. Stax have always preferred "thin and bright" tonality, which is not at all accurate, but certainly attractive if you like that kind of sound. I lived with a pair of SR-3 that I used on location for mixing for many years so you can certainly get used to or adjust to that sound, but if possible, in my not so humble opinion, you should Equalize every headphone you encounter to help linearize it.

I much prefer "natural" sound to over bright so if (as someone just said in this thread) the 007 Mk2 is an "outlier" I would say, bravo, because it's warmer and more accurate than a lot of the other Stax. I don't know what Stax were thinking making the more expensive 009 so much brighter than the more accurate 007.

I have a pair of pro diaphragms that were originally in a Lambda, now they are inside of an SR-5 case that I had. Someone (I forget who, sorry) put the pro diaphragms in my SR-5 case for me. Like so many of the older Stax phones, those sound very bright and thin. They are also about 6-10 dB hotter (more sensitive) than any current circumaural stax. But surprisingly, after EQ, that old pro model that's in an SR-5 case sounds very respectable! It can take a bass boost without overload --- and I'm quite pleased with what these old phones can do. So, the ingredients you need are: A high headroom Stat amplifier, and a great DAC with EQ (like the RME I mentioned). Feel free to write me for my EQ settings, it will get you in the ball park and you can tweak to your taste from there.

 

[gammi]

Just got some in ear microphones and did an on head sweep with my X9000. Nice results, very flat, very smooth. Just the usual few dB hump around 1k. Posted them over in the X9000 thread and thought I should link over here too.

https://www.head-fi.org/threads/stax-sr-x9000.959852/page-204#post-18131516

Edit: added a Susvara comparison too.
Edit 2: The Susvara vs X9000 comparison would up turning into a whole shootout between nine different high end headphones, so I made a new thread for it.

https://www.head-fi.org/threads/gammis-mega-headphone-shootout.972886/

Regarding STAX specific tests I did, X9000 looks the best imo. But Nova Signature looks really nice too, like a better SR-007 with more bass and more treble. Likely want to tame that spike at 1.7k though. SR-007 doesn't look good objectively. Big dips in sub bass and at 1.2k and 3k. But subjectively, a lot of people love it. Sounds warm because of the treble roll off and a little bit of a mid-bass hump.

Nova Signature actually looks a lot like X9000 just with less 700-1k and more 1k-2k. For those of you here who like LNS but not X9000, this area is worth messing around with to see if it improves things for you.

 

[aokman]

I am absolutely not a fan of the Lambda-style Stax headphones, I was always uncomfortable with the imaging and even the tonal response. The circumaural style Stax is the only way to go in my opinion. The 007 Mk2 in my opinion sounds much more accurate than the 009, The 009 is way too bright. Even then, the 007 is bright and a bit thin in the bottom, but far more neutral than any previous circumaural model Stax. After I got my Audeze CRBN headphones I put my 007 Stax in its case and it sat there for about 2 years. It was already at least 10 years old. But I recently pulled out the 007 to revisit the phone and I find pleasantly that it seems to have aged very nicely just sitting in the box! Yeah, it could be my imagination, but I think that the diaphragm tension may have loosened a bit and so the bass response is much more extended than I remember it and the high end has softened in a nice way. It also has the Spritzer port seal mod. I'm very impressed now, the "aged" 007 sounds really nice!

I have EQs that I have implemented for each phone that I have to subjectively match my calibrated mastering loudspeakers. I now use an RME ADI-2 FS DAC for EQ and headphone drive. The line output feeds my custom transformer-based Stat amp and the headphone outputs feed the dynamic phones. The RME is so smart that when you plug in the dynamic phone it automatically switches to the eq and balance settings for that phone, and when you unplug the dynamic phone it switches to the last EQ setting that I used for the Stats. So comparing the Stat to the dynamic is painless.

The EQ I have used for the 007 has a bass boost (among other bands) and the 007 takes that boost very comfortably without any overload, as long as you are using a high headroom amplifier like my KGSS Carbon or my new transformer-based Stat amp that I built. If I give the equalized Audeze CRBN a 10 grade, I can now happily give the equalized Stax 007 Mk2 a 9.5! At that point it only lacks a bit in soundstage width and height compared to the CRBN, but tonally after EQ the two are almost on a par. On the same grading scale, my equalized Audeze LCD-5 gets a 9, so things are very nice at casa Katz. I have two CRBNs, one 007 Stax and one LCD-5 and with EQ I consider all 4 phones to be reference-quality!

I love my L700s to be honest, if I want darker and punchy headphones, I go back to my Klipsch HP3s and party mode. That said the X9000s are on my radar now as I climb the ladder (If i stop spending money on transformers and amps). That said Corina has my interest also but cannot own them all…

 

[padam]

The older you go in the Circumaural Stax, the brighter they were. Stax have always preferred "thin and bright" tonality, which is not at all accurate, but certainly attractive if you like that kind of sound. I lived with a pair of SR-3 that I used on location for mixing for many years so you can certainly get used to or adjust to that sound, but if possible, in my not so humble opinion, you should Equalize every headphone you encounter to help linearize it.

I much prefer "natural" sound to over bright so if (as someone just said in this thread) the 007 Mk2 is an "outlier" I would say, bravo, because it's warmer and more accurate than a lot of the other Stax. I don't know what Stax were thinking making the more expensive 009 so much brighter than the more accurate 007.

I have a pair of pro diaphragms that were originally in a Lambda, now they are inside of an SR-5 case that I had. Someone (I forget who, sorry) put the pro diaphragms in my SR-5 case for me. Like so many of the older Stax phones, those sound very bright and thin. They are also about 6-10 dB hotter (more sensitive) than any current circumaural stax. But surprisingly, after EQ, that old pro model that's in an SR-5 case sounds very respectable! It can take a bass boost without overload --- and I'm quite pleased with what these old phones can do. So, the ingredients you need are: A high headroom Stat amplifier, and a great DAC with EQ (like the RME I mentioned). Feel free to write me for my EQ settings, it will get you in the ball park and you can tweak to your taste from there.

Cheers Bob, I don't forget, since I don't have that many friends
Those were mine originally, and those drivers were transplanted from am SR-Gamma Pro, since as you said Lambdas are a different shape.
Kind of funny that it's just been brought up: https://www.head-fi.org/threads/stax-sr-x1-new-entry-model.971680/post-18072756
As I've just tested a new prototype of an SR-5 Pro conversion done by another person in a new way.

Does remind me of that pair I sold to you - but I don't evaluate it the same way.

On the Carbon amplifier, I find it to be surprisingly dark, darker than an SR-007 Mk1, because of the limitations regarding the smaller, much more damped housing means the treble response isn't as capable.
And if I were to apply any EQ to it, I would aim do the exact opposite, e.g. brighten it up to restore clarity.
https://www.dropbox.com/s/vzfx5kw28r64gac/Stax SR-5 Gold.pdf?e=1&dl=0
This is the SR-5NB used with a Stax amplifier which is of course not identical to using a Pro version on a Carbon, both of which change the sound notably.
The SR-5 Pro a headphone where I'm not inclined to push the volume too high on the Carbon - bass actually gets overpowering, which is rare to see on any Stax.
I found it to be quite an addictive for classic rock, where an SR-007 might be "too refined, overly smooth".

For me, there is also a very clear distinction between an even/smooth response and balanced tonality (e.g. not bright or dark etc. but this is actually quite hard to judge depending on which colorations weigh in more on that, so quite a personal judgement)
And while I may not achieve the same balance as with a speaker, I might not actually aim for that.
As high-end headphones do have other attributes against speakers, that may actually worth putting more emphasis on.

So yes, I'd say that while this may be an oversimplification, but an SR-Omega and SR-007 Mk1 are in general brighter than an SR-007 Mk2.
But I would rather have that than an SR-007 Mk2, which might be more balanced on a brightness/darkness scale.
But - and there is a big but - it is also filled with even more dips and bumps in the frequency response that bother me more, and no EQ is going to bring that up to the same level of transparency. I tried suited EQ curves for both Mk1 and Mk2 versions so in essence they are corrected to the same target (provided that these curved matches the actual samples I testead) and yet: the Mk1 still sounded better to my ears for the most part. (considerably smoother, more open soundfield, while Mk2 has slightly better bass impact)

I also extensively tested the RME DAC as well as a Prism Lyra 2, the latter particularly stood out like an exceptional D/A converter on its own, technically speaking.
But - and a big but again - I also found neither to be very well suited to Stax headphones in general: sound became brighter, "more digital", unpleasant to my ears, while the Lavry DA11 does take a bit of a hit with regards to clarity, but it also seems to sound more natural, less bothersome, without injecting a heavy signature of its own.

So one day maybe, I'd like something similar to that. Technically more capable, but without injecting changes on what I've already set up (if I could achieve even more fullness without changing any other attributes, I would certainly take that as I could lower my listening level)
Maybe a Bricasti M1 Series II or something could be worthwhile for an otherwise fairly sophisticated setup to make it "more complete" - unfortunately very expensive...

 

[bobkatz]

Cheers Bob, I don't forget, since I don't have that many friends

No way, you remembered me! Sorry I forgot it was you.

Those were mine originally, and those drivers were transplanted from am SR-Gamma Pro, since as you said Lambdas are a different shape.
Kind of funny that it's just been brought up: https://www.head-fi.org/threads/stax-sr-x1-new-entry-model.971680/post-18072756
As I've just tested a new prototype of an SR-5 Pro conversion done by another person in a new way.

Does remind me of that pair I sold to you - but I don't evaluate it the same way.

On the Carbon amplifier, I find it to be surprisingly dark, darker than an SR-007 Mk1, because of the limitations regarding the smaller, much more damped housing means the treble response isn't as capable.

The Mjolnir Carbon amp is definitely shall we say "warm" but i think in a nice way. With the 007 M 2 I also do a little brightening at the top. At least with my aged 007's. My 007's predate the Carbon amp and either they've warmed over time or my memory is faulty, or what I recall was with the older KGSS that I had (which was a bit bright I thought). The older KGSS is an older generation and I think it was a good attempt, but the Mjolnir Carbon is such an improvement on it.

I need to get some new pads for my old "pro-ized" SR-5. Would SRX earpads work?

My custom transformer based Stat amp is sweet, warm and punchy, a hair light in the bass below 100 Hz. It's an excellent competitior to the Mjolnir Carbon and surprisingly, I have no preference, I like both amps as long as I can equalize the phones for the phones and the amp.

Attached are my headphone EQs and you can see that I also need to do a little HF rise for my 007s. All of my EQs have been empirically created by matching them up as close as possible with my calibrated loudspeakers in my mastering room which have a slight bass rise below 125, then are flat up to 1 kHz, then HF rolled off to something close to the B&K curve.

I like the RME DAC, its line output sounds quite neutral to me. I have not shot it out directly against my Prism Lyra, but I feel that both DACs are in the same league sonically. Except the Prism does not have built in EQ like the RME. My tests for DACs have been to put them into a pitch and catch situation (out DAC ----> in ADC) and capture the return into my DAW to compare with the source. In no case, including the Prism, the Cranesong Hedd Quantum and now the Grimm UC-1, does the return come close to the original. There is always some loss of depth and spatiality. Right now the Grimm is the winner, by a nose. But to my ears in the pitch and catch, the losses I hear are in depth and space and clarity. But I have not perceived any harshness or brightness with any of the premium DACs I mentioned, just different degrees of loss of space or clarity. So we have to agree to disagree. I have never auditioned a Lavry, however.

Here's where we disagree: With EQ, into either my Mjolnir Carbon or my new custom transformer-based stat amp --- I find the RME DAC to be very nice, clean and accurate. Neither dry nor pure, just simply neutral.

Attached are some screenshots of 4 EQs. If you compare EQ #1 versus #2, it shows the subtle differences between the two Stat amps, using the Audeze CRBN as a constant headphone. The BK Stat amp needs a bit more HF rolloff and/or bass boost. But in the end both amps sound marvelous with the BK transformer amp sounding a bit "fatter" but not in any objectionable way.

EQ #3 by comparison is the 007 Mk 2 with the BK stat amp. Absolutely it needs a bit of an HF rise, so here you and I agree considerably. Again, I do not remember that need so either my memory is faulty, or the headphone has aged, or my memory of the 007 goes back to my old KGSS amp which I sold which I felt sounded bright. I really like the Mjolnir Carbon, however, it has the warmth that I seek. I am quite impressed by the 007 Mk2 with proper EQ compensation. it does not have the imaging/soundstage of the Audeze CRBN, but it's right up there in tonality and punch now. I give the equalized CRBN a 10 grade and the equalized 007 Mk2 a 9.5. They are both excellent headphones.

EQ #4 by comparison is the old, pro-ized by you SR-5. It's a bright and thin phone with out EQ and it does not throw a big soundstage like the two giant circumaural successors but I not would throw this equalized phone out of bed! Not at all...after this EQ it's very respectable. With this EQ I feel the old SR-5 is now a a "reference grade" phone. And amazingly, all three of these Stats can take a bottom end boost to compensate for their relative weaknesses, without overload.

In all respects, the three equalized stat phones beat all of my planar dynamics. The equalized Audeze LCD-5, however, comes the closest with EQ and I give it a surprising 9 grade. Audeze worked real hard to make the LCD-5 have the best pinnae-compensation curve out of the box.

I had the Bricasti DAC on trial and did not like it, it sounded bright to me. I know there have been a lot of firmware upgrades for this DAC so it's a chameleon at this point and who knows what version anyone is evaluating.

And if I were to apply any EQ to it, I would aim do the exact opposite, e.g. brighten it up to restore clarity.
https://www.dropbox.com/s/vzfx5kw28r64gac/Stax SR-5 Gold.pdf?e=1&dl=0
This is the SR-5NB used with a Stax amplifier which is of course not identical to using a Pro version on a Carbon, both of which change the sound notably.
The SR-5 Pro a headphone where I'm not inclined to push the volume too high on the Carbon - bass actually gets overpowering, which is rare to see on any Stax.
I found it to be quite an addictive for classic rock, where an SR-007 might be "too refined, overly smooth".

For me, there is also a very clear distinction between an even/smooth response and balanced tonality (e.g. not bright or dark etc. but this is actually quite hard to judge depending on which colorations weigh in more on that, so quite a personal judgement)
And while I may not achieve the same balance as with a speaker, I might not actually aim for that.
As high-end headphones do have other attributes against speakers, that may actually worth putting more emphasis on.

So yes, I'd say that while this may be an oversimplification, but an SR-Omega and SR-007 Mk1 are in general brighter than an SR-007 Mk2.
But I would rather have that than an SR-007 Mk2, which might be more balanced on a brightness/darkness scale.
But - and there is a big but - it is also filled with even more dips and bumps in the frequency response that bother me more, and no EQ is going to bring that up to the same level of transparency. I tried suited EQ curves for both Mk1 and Mk2 versions so in essence they are corrected to the same target (provided that these curved matches the actual samples I testead) and yet: the Mk1 still sounded better to my ears for the most part. (considerably smoother, more open soundfield, while Mk2 has slightly better bass impact)

I also extensively tested the RME DAC as well as a Prism Lyra 2, the latter particularly stood out like an exceptional D/A converter on its own, technically speaking.
But - and a big but again - I also found neither to be very well suited to Stax headphones in general: sound became brighter, "more digital", unpleasant to my ears, while the Lavry DA11 does take a bit of a hit with regards to clarity, but it also seems to sound more natural, less bothersome, without injecting a heavy signature of its own.

So one day maybe, I'd like something similar to that. Technically more capable, but without injecting changes on what I've already set up (if I could achieve even more fullness without changing any other attributes, I would certainly take that as I could lower my listening level)
Maybe a Bricasti M1 Series II or something could be worthwhile for an otherwise fairly sophisticated setup to make it "more complete" - unfortunately very expensive...