The Headcase Stax thread

[spritzer]

It's the "always on" bias supply and shouldn't be like that. Send Justin a PM and he'll sort it out for you or tell you how to do it your self.

[justin]

It looks like that amp was modified. I don't use those gray resistors. The capacitor lead should be plugged into ground on the terminal block, it reduces noise

[GPH]

It looks like that amp was modified. I don't use those gray resistors. The capacitor lead should be plugged into ground on the terminal block, it reduces noise

Thanks, I just did that and there's no noise now.

[spritzer]

It looks like that amp was modified. I don't use those gray resistors. The capacitor lead should be plugged into ground on the terminal block, it reduces noise

Who uses Caddock's in a bias supply? I was also trying to figure out why they were there as the amp already has a HE90 output.

[justin]

no idea, i use 3kV rated metal films there

[GPH]

Who uses Caddock's in a bias supply? I was also trying to figure out why they were there as the amp already has a HE90 output.

I don't understand what that means.

[spritzer]

I don't understand what that means.

Adding resistors after the bias supply only makes sense if you want to go up to 10Mohm to better suit the HE90 or install a dividing network to drop the voltage. The latter makes no sense with the pot already there...

[GPH]

Adding resistors after the bias supply only makes sense if you want to go up to 10Mohm to better suit the HE90 or install a dividing network to drop the voltage. The latter makes no sense with the pot already there...

Sorry if I appear like a complete noob, but I really appreciate your input about this.

What you're saying is that I should scrap these resistors and solder the wires directly?

[spritzer]

Sorry if I appear like a complete noob, but I really appreciate your input about this.

What you're saying is that I should scrap these resistors and solder the wires directly?

Without knowing why they were added I'd leave them in place for know. What output sockets are connected to that bias supply and is the one in the PSU populated?

[luvdunhill]

maybe that cap was being used as an RF antenna? KGSS with a built in FM tuner, sweet idea!

[spritzer]

maybe that cap was being used as an RF antenna? KGSS with a built in FM tuner, sweet idea!

That's not a bad idea. When can I order my MarcE special edition?

[justin]

Without knowing why they were added I'd leave them in place for know. What output sockets are connected to that bias supply and is the one in the PSU populated?

the bias board was only designed for 1 jack, so there is a 4.7M resistor soldered onto the board. Additional resistors can be added for each jack. I guess the previous owner decided to replace them with Caddocks

[luvdunhill]

That's not a bad idea. When can I order my MarcE special edition?

I'm waiting for Ray's amp to ship first... I want to make sure I can support a good lock onto his specific oscillation frequency. It will be the first electrostatic-to-electrostatic communications network... mil-spec of course... in fact, this message is classified and will self-destruct.

[spritzer]

the bias board was only designed for 1 jack, so there is a 4.7M resistor soldered onto the board. Additional resistors can be added for each jack. I guess the previous owner decided to replace them with Caddocks

Kind of reminds me of this picture:

V-Caps in the bias supply? Not that the other caps pass signal either...

I'm waiting for Ray's amp to ship first... I want to make sure I can support a good lock onto his specific oscillation frequency. It will be the first electrostatic-to-electrostatic communications network... mil-spec of course... in fact, this message is classified and will self-destruct.

Sounds interesting. Will this be RSA and MarcE only system or will it expand later on?

[catscratch]

Right, don't take these impressions for granted, since I'm pretty drunk. But, I do have the O2 Mk1 and the O2 Mk2 side-by-side.

What I notice immediately is that the Mk1 is much more linear in the bass. There is none of the Mk2's annoying midbass hump, and the bass is deeper. This works in two ways: in tracks that are deficient in bass to begin with, the Mk1 feels very bass-light. The Mk2's midbass boost actually helps it in dealing with thin recordings. But, in tracks that are full in bass, the Mk1 comes alive, whereas the Mk2 just sounds thick and boomy. So, the Mk1 is more accurate in the bass, better in good recordings - but worse on bad ones.

Also, I immediately notice that the Mk1's midrange tone is very different. It's much more neutral. It's not warm, mind you! I actually would prefer a warmer midrange tone. Rather, this is pretty much spot-on accurate. Think HD600 rather than HD650, and you'll get the picture. The Mk2 is distinctly boosted in the upper mids, which makes the midrange colder and somewhat harsher - but also more vibrant on some recordings.

Speaking of mids, the Mk2 is more forward in the mids. The Mk1 isn't recessed in the mids; it's actually just about ruler-flat, but the Mk2 has more boosted mids as a whole. That makes it more forward sounding than the Mk1. Also, curiously enough, the Mk1 sounds brighter on some tracks. When its midrange isn't quite as forward and its bass is more reflective of the insufficient bass on the recording, it can come off as pretty bright. Once again, this is more accurate since it's showing more of what's on the recording.

The Mk2 is distinctly more airy sounding. The headstage is bigger, and there seems to be more air and space between instruments. The Mk1 is more focused, and the headstage is smaller, though it portrays dimensional cues just as well, if not better than the Mk2. On the whole, I actually like the way the Mk2 does soundstage more.

But, in most respects, the Mk1 wins. It seems to me that the Mk1 is the ultimately neutral, ultimately accurate design. With the Mk2, the net effect is to take the Mk1 sound and make it more SR-404-ish. It's livelier, more forward, more vibrant, but the frequency response is messed up. It uses colorations to achieve this effect rather than being naturally more forward, more lively, and more vibrant. On some recordings, especially with rock, the Mk2's particular presentation makes for a more engaging listen. But on the whole, the Mk1 presents exactly what's on the recording, and does it in a very neutral, but still very lush and "wet" sort of way. It's more laid-back, a bit less thumpy in the bass, but also more transparent, and tends to disappear much more.

Now, my rig isn't good enough for either headphone to disappear completely, but while I'm aware of the Mk2's colorations, for good and ill, at all times, the Mk1 tends to let go a lot more and let the music come through.

So, to summarize:

Mk2:

- more forward in the midrange

- colder in the midrange with elevated upper mids

- airier sound with bigger headstage

- boosted midbass

- lacking deep bass

- lively and vivid but more colored

Mk1:

- ruler flat FR

- accurate, rather than warm tone in the mids

- linear bass, with no noticeable bass boost anywhere

- more relaxed and laid-back

- tighter, more focused soundstage with no artificial airyness

When all is said and done, I prefer the Mk1. I'll listen a bit more tomorrow when I'm sober, since believe me, I'm in no fit state to make comparisons, though the above does stink of truth (and booze).

But, before this, I was ready to dismiss the Mk2 as a failed design, a misstep in Stax's lineup, if you will. Right now, I think that it's not as good as the Mk1 but it's still one of the best headphones I've ever heard. It has a different sound and a different personality, and it's definitely more colored, but it's by no means anything other than a really good headphone. Just not the best one out there, unfortunately. Which the Mk1 very well may be.

Oh yeah, I actually find the Mk1 to be more comfortable, but that's because my particular pair has a headband that's more worn-in, and less tight. The Mk2's headband tends to pull the headphones out of position for me, but I'm sure with more wear, it will feel more natural.

[dvse]

Pretty much spot on how I heard the difference between SR-007 and SR-007A but a lot more eloquently expressed, although I actually preferred the more precise soundstage of the earlier model.

So I guess the evidence is mounting, unless we are all victims of groupthink

[spritzer]

Very good comparison you've got there. I'm with dvse on preferring the smaller, more precise headstage of the Mk1 but I also like the more rounded soundstage of the SR-Omega. The Mk2/A with the latest round of mods does sound pretty similar to the Mk1 though more forward. I quite like them though and now the hard part is to modify the Mk2 pads...

As for the comfort then the elastic band on the Mk2/A is much stronger so I'm not sure it will loosen up over time. I do how ever prefer the material on the bottom of the headpad on the Mk2.

[Dusty Chalk]

Catscratch -- you pretty much nailed it on the head with the bass, that was the first thing I noticed. I mostly agree with what you said about recordings, though, being a basshead, I'd go one step further -- when I want that midbass hump, I'd reach for the Mk 2's, and when I don't, I'd reach for the Mk 1's. "Rocking out" comes to mind as to when I'd want it.

Kind of makes me wonder how they'd respond to EQ...

[catscratch]

RE soundstage: I'm basically a sucker for HE90-like colorations, and keep in mind that ambient and downtempo electronica is a lot of my listening material. There, these kinds of colorations work very well. So, I don't know if the Mk1 is The Headphone for me, but it's certainly the best in my collection so far, and easily the most accurate headphone I've ever heard.

RE bass: The issue with the Mk2's bass isn't that it's boosted. The problem is that it's uneven. The midbass is overblown and the deep bass is lacking, and even on rock, if you listen closely to the bassline, you'll hear the bass getting fuzzier and quieter as the notes go lower and lower. With the Mk1 that doesn't happen; the bass is very even. I am also a bit of a closet basshead, and I wouldn't mind a general bass boost, but the Mk2 only boosts a specific part of the bass, and therein lies the problem.

RE groupthink: Nah, I think we're just experienced people that know our stuff and have the balls to come out and say what we think. Every time someone gets a shiny new toy and it doesn't perform to par there is a strong desire to make excuses and justify it. I've done that to some extent early on in my audio career, and I'm sick of it. I want my gear to get it right, especially when I'm paying top dollar for it.

Well, now I have two tasks: 1) to modify a 240V SRM-717 to 117V, and 2) to find a synergistic source for my whole rig, depending of course on how the Mk1/717 combo will sound. The above comparison was on the SRD-7 Pro/Dared VP-20 setup, and it's actually pretty damn good overall. But, there's room for improvement.

[Dusty Chalk]

...the deep bass is lacking, and even on rock, if you listen closely to the bassline, you'll hear the bass getting fuzzier and quieter as the notes go lower and lower.

This didn't happen on neither the ES-1 nor the BHSE. So it might be the amp. Or it might've been that I wasn't listening to "testing" enough music, which, I have to admit, could well have been the case.

[spritzer]

RE soundstage: I'm basically a sucker for HE90-like colorations, and keep in mind that ambient and downtempo electronica is a lot of my listening material. There, these kinds of colorations work very well. So, I don't know if the Mk1 is The Headphone for me, but it's certainly the best in my collection so far, and easily the most accurate headphone I've ever heard.

SR-Omega it is then but be prepared to pay dearly for one if you should find it. Going rate in Japan is close to 400kYen and even more here in the west. Think of it as a rounder and slightly woollier version of the SR-007 with a larger soundstage.

RE bass: The issue with the Mk2's bass isn't that it's boosted. The problem is that it's uneven. The midbass is overblown and the deep bass is lacking, and even on rock, if you listen closely to the bassline, you'll hear the bass getting fuzzier and quieter as the notes go lower and lower. With the Mk1 that doesn't happen; the bass is very even. I am also a bit of a closet basshead, and I wouldn't mind a general bass boost, but the Mk2 only boosts a specific part of the bass, and therein lies the problem.

Like I say later on this is due to the amplification. What I've been banging on for 5 years now is that the SR-007 needs a shit load of power to wake up the bass but all that power will not act as a bass boost. What will increase the bass is playing around with the arc's by making the phones slightly looser on the head. The angle is also important but it matters less then the pressure.

RE groupthink: Nah, I think we're just experienced people that know our stuff and have the balls to come out and say what we think. Every time someone gets a shiny new toy and it doesn't perform to par there is a strong desire to make excuses and justify it. I've done that to some extent early on in my audio career, and I'm sick of it. I want my gear to get it right, especially when I'm paying top dollar for it.

Ditto. The HF way is to blame everything on burn-in but some gear just doesn't work as it should and we are simply not kidding our selfs. I know what I like and how a SR-007 should sound and the Mk2 just isn't that. The modded unit is better but still not there.

Well, now I have two tasks: 1) to modify a 240V SRM-717 to 117V, and 2) to find a synergistic source for my whole rig, depending of course on how the Mk1/717 combo will sound. The above comparison was on the SRD-7 Pro/Dared VP-20 setup, and it's actually pretty damn good overall. But, there's room for improvement.

Very easy to do most of the time. Remove the 4 screws which hold the top cover, remove the screws which secure the back panel and tilt it so you have better access to the jumpers. For 240v they should be jumpers at 2 and 5 but for 120v you need to have jumpers at 2,4 and 6. If you are missing one jumper then a fuse should work if it has a large enough rating.

This didn't happen on neither the ES-1 nor the BHSE. So it might be the amp. Or it might've been that I wasn't listening to "testing" enough music, which, I have to admit, could well have been the case.

It's most definitely the amplification. You have to remember how electrostatics work (lower impedance into bass and treble) and the SR-007 is a current hog into the lower frequencies. I guess the built in damping was the only way for them to overcome the upper midrange colorations found both in the He90 and SR-Omega but it creates a very tough load on the amps.

[catscratch]

SR-Omega it is then but be prepared to pay dearly for one if you should find it. Going rate in Japan is close to 400kYen and even more here in the west. Think of it as a rounder and slightly woollier version of the SR-007 with a larger soundstage.

I'll also check out the EH1.2b, if it ever appears to have become a viable commercial product and not just a prototyle. I'm still following the 1.2b drama closely, and I hope something good will come of it, if only to motivate Stax to get their act together.

The expense of the SR-Omega, together with its rarity and its propensity for driver failure, makes me think twice about trying to find one. If it's not a stretch financially then I'll go for it, but ATM it's a risky investment.

Will keep you posted on how the 717 works out. Is it possible to substitute jumpers from other sources if I'm missing one? And where would I go by getting my hands on them?

[GPH]

I've had the KGSS for a couple of days now and I think it's time for a short report.

First thing I noticed when I listened to the OII plugged in the KGSS is the big difference in bass presentation compared to the SRM-T1S. With the Stax amp, the bass is there, but it sounds cloudy and unfocused. With the KGSS, the OII bass suddently becomes punchy and has a lot more body. It's much closer to what I expect to hear from an electric bass or a double bass in a live setting.

As for the midrange, I really liked the T1S presentation and I really can't say if the KGSS is better or worse. It does things differently and presents perhaps a dryer midrange, but slightly more accurate and tight. The midrange on the T1S is a lot more lush and seducing, but sacrifices some micro-details that I hear on the KGSS. With that said, the KGSS really destroys bad recordings as it's incredibly revealing.

For the treble, I'd say the KGSS has slightly more extension than the T1S, but like for the midrange, it's dryer and has no mercy for harsh and sibilant recordings. It's very precise and all the details are there. I've done some comparisons with my Etys which are still my reference for extracting the last small details in a recording and I have to say the Stax did pretty well. It still misses some very small details, but the experience is way more satisfying than the Etymotics as a whole.

One thing that surprised on the KGSS is the soundstage. It sounds more compact than on the Stax amp, but I'd say the instrument placement is slightly more accurate. I was expecting a wider soundstage though from some reviews that I read, but it's not what I experience. In the end, soundstage on headphones is all artificial so it doesn't really matter, but I have to say I was a little bit diappointed at the beginning. Soundstaging on the Lambda series is still the best I've heard on headphones.

One final observation. It's been too years since I've started my headphone journey and I pretty much invested the maximum budget that I can afford in my actual setup. There are still many upgrades possible, but I doubt it gets *a lot* better than what I have now (correct me if I'm wrong). While it sounds great and it's a really satisfying experience, there are some days where I feel I should downgrade to something more minimalist (say ESP-950 or HD580 setup) and start a small bookshelves rig on the side. Headphones are great, but there are some qualities I'm looking for that they just can't provide (lifelike bass thump and soundstage). Anyway, I plan to enjoy this setup for a little while, but I'm not sure what avenue to take next.

[catscratch]

HOLY FUCKING EARGASMS BATMAN!!!

I just got the sense, coming off a nice listening session, that the world sounds dull and lifeless compared to my rig. You know you have something special on your hands when you're getting that feeling. It's not something I've felt for a few years now, excluding my brief and partially successful stint with running the HD650 in push-pull mode off my speaker amp. That rig was magic, and this rig sounds surprisingly similar, but with a much more neutral tonality and more speed/detail all-around.

Still countless room for improvement in the signal path, of course, but the magic is back. Seriously, listening to Shpongle just now was like losing your body and letting your mind float through an infinite ocean of brilliant light.

There is also a very definite K340 vibe going, at least in terms of how my K340 sounded. In fact, it's eerie how similar the two headphones are. The O2 doesn't have the K340's colorations, either the warmth in the midrange or the annoying echoey reverb, and on a purely technical plane it's on another level. But, the magic that the K340 had is present here as well.

GPH: Thanks for the impressions, the KGSS is an amp I definitely have on the menu as a potential main course. Regarding your impressions of its drier tonality next to the T1 - is it simply a drier tonality than the T1, or a dry tonality in the absolute sense? I love the liquid, "wet" sound that I'm getting out of the O2 in my rig, and I would hate to lose that. I haven't hooked up the 717 yet but I am afraid I may lose out on that liquid aspect even with the supposedly warmer-sounding 717. Right now, the rig is magically fluid and organic, but the transformer box doesn't have the power to make the bass as tight as it should be.

[dvse]

As for the midrange, I really liked the T1S presentation and I really can't say if the KGSS is better or worse. It does things differently and presents perhaps a dryer midrange, but slightly more accurate and tight. The midrange on the T1S is a lot more lush and seducing, but sacrifices some micro-details that I hear on the KGSS. With that said, the KGSS really destroys bad recordings as it's incredibly revealing.

<...>

One thing that surprised on the KGSS is the soundstage. It sounds more compact than on the Stax amp, but I'd say the instrument placement is slightly more accurate. I was expecting a wider soundstage though from some reviews that I read, but it's not what I experience. In the end, soundstage on headphones is all artificial so it doesn't really matter, but I have to say I was a little bit diappointed at the beginning. Soundstaging on the Lambda series is still the best I've heard on headphones.

I have pretty much the same setup, and it never really sounds offensive even on poorer recordings. You can hear the problems easily but they do not detract from the musical content too much. There is a good chance that the problem is with your source - a lot of cheaper (and more expensive) digital have certain treble harshness that more resolving downstream equipment helps to reveal. Try any analogue setup or, if possible, high end digital to see the difference.

Regarding the soundstage, KGSS is more focused and accurate than the Stax offerings I've heard - it may take a while to get used to, but ultimately more 'real' and enjoyable... Similar to Lambda vs. SR-007 really, although less dramatic. So give it some more time and it might grow on you.