The Headcase Stax thread

[Voltron]

Sounds almost perfect.

[catscratch]

Has someone measured the O2 Mk2 against the O2 Mk1? I would wager that there will be some interesting things there.

[deepak]

I'd also like to know how old (or new) the pads were on those measurements. I swapped out my SR-007 MK1 pads out in November and the difference was startling. The measurements on the SR-Omega look freakin' good.

[spritzer]

The condition of the pads is a huge part of the sound and also the angle of the drivers compared to the mic. The SR-Omega is much easier to measure as the drivers swivel and the pads hold their shape, even after 15 years.

[Asr]

From Justin's 12/2 update on his Web site:

A new version of the Blue Hawaii electrostatic amp will be shipping soon to those who have made a reservation for one of the 20 units to be built. All have been reserved and because of the demand, another run of the Blue Hawaii SE will be built to ship in Spring 2009. We will begin taking reservations for the 2nd run after the first 20 units begin shipping later this month.

The Blue Hawaii SE features a separate power supply of a new design, many improvements to the amplifier circuitry, higher quality components, and build quality on a new level for electrostatic headphone amps. Inputs are 2 RCA and 1 XLR, and a set of XLR and RCA tape outputs. There are 2 headphone outputs, which can be for Stax or Sennheiser Orpheus, or one of each. The volume control is a DACT CT2 stepped attenuator or an optional Alps RK50 potentiometer.

wahoo!

The Order page also lists the 2nd run at $4995...

(and incidentally, it looks like he also has AE-2 and Gilmore Lite amps in stock atm)

[indikator]

....

The main problem is the PCBs. To order them I need files. Kevin said that he can't provide them because of the agreement with Justin, who designed them, but Justin willing to sell the boards. Which is very good, because it will be cheaper and easier just to buy them from him? I ask (emailed) Justin, asking if he have them, and looks like my message was lost in tons of other emails, from angry headfirst who were waiting imptient for thier builds, KGBH SE included .

On the other hand I heard that in the near future will be new redesigned two boards PSU (one per channel, not two on the same board), which be able to provide 500v. Plus the original designed schematic has been tweaked, and is now KGBH SE.

So I decided to wait and hope that all of that will be available in the near future to regular DIYer.

.....

same story here tehehe;D

just wanna know, if the new design is going to be opened?

if it is, are there some rare transistor that we should hunt early before it completely disappeared?

[spritzer]

same story here tehehe;D

just wanna know, if the new design is going to be opened?

if it is, are there some rare transistor that we should hunt early before it completely disappeared?

While it certainly isn't a secret what transistors Justin is using now I'm not really sure why he would release the schematics.

[indikator]

no idea here...I'm not too deep into electronics,

and for the reason, off course it is "the spirit of DIY":dan:

or maybe to allow a poor student like me to get one:palm:

[faust3d]

Ok, I was just trying to get a reference in my mind. It does look inline with the SR-Omega graph which Stax posted back in the day and pretty close to to the ideal.

This FR graph makes me drool. I also love the LNS graph.

[Asr]

Stax SR-X MK3 and SR-007 MKI - impressions

The SR-X is definitely my favorite of the Stax headphones that I own, which includes the SR-007 MKI and MKII and SR-Lambda. I wouldn't say it's perfect for all of my sonic preferences though, as the bass doesn't have the snap or agility that the Audio-Technica AD2000 does, but it's still very decent quantity. Its treble is good, it's fast, and it's clear-sounding, which is pretty much what I look for from headphones (minus the bass part).

I jumped on the SR-X MK3 after I heard the SR-5NB at the NorCal 6/28/08 meet, since I liked the SR-5NB a lot and I read that the two headphones have the same drivers, and it sounds really good on my setup, amped by the SRM-T1 right now (Sherwood has my SRM-1 MKII). The SR-X sounds so good that it's completely changed the game for me actually - I was thinking about not keeping an elecrostatic system long-term but will have to reconsider now.

As for the OII MKI, it sounds really good too, off the SRM-T1. I like it more than the MKII, there's less of that annoying mid-bass bump and the treble is clearer too. There's nothing about its sound that's an instant "wow" factor, which is why I originally wrote it off after a 5-10 minute audition at the NorCal 8/25/07 meet (it was amped by the KGSS DX at that meet), but after some extended listening, I can tell there's definitely a lot of subtlety packed into it that only further listening will reveal.

I'm really looking forward to hearing all four of my Stax headphones on my imminent BHSE now, especially the Normal-bias ones.

[HeadphoneAddict]

Stax SR-X MK3 and SR-007 MKI - impressions

The SR-X is definitely my favorite of the Stax headphones that I own, which includes the SR-007 MKI and MKII and SR-Lambda. I wouldn't say it's perfect for all of my sonic preferences though, as the bass doesn't have the snap or agility that the Audio-Technica AD2000 does, but it's still very decent quantity. Its treble is good, it's fast, and it's clear-sounding, which is pretty much what I look for from headphones (minus the bass part).

I jumped on the SR-X MK3 after I heard the SR-5NB at the NorCal 6/28/08 meet, since I liked the SR-5NB a lot and I read that the two headphones have the same drivers, and it sounds really good on my setup, amped by the SRM-T1 right now (Sherwood has my SRM-1 MKII). The SR-X sounds so good that it's completely changed the game for me actually - I was thinking about not keeping an elecrostatic system long-term but will have to reconsider now.

As for the OII MKI, it sounds really good too, off the SRM-T1. I like it more than the MKII, there's less of that annoying mid-bass bump and the treble is clearer too. There's nothing about its sound that's an instant "wow" factor, which is why I originally wrote it off after a 5-10 minute audition at the NorCal 8/25/07 meet (it was amped by the KGSS DX at that meet), but after some extended listening, I can tell there's definitely a lot of subtlety packed into it that only further listening will reveal.

I'm really looking forward to hearing all four of my Stax headphones on my imminent BHSE now, especially the Normal-bias ones.

I would love to meet up sometime and compare O2 Mk1 vs my O2 Mk2, and maybe SR-X vs my SR-5NB - I'm just afraid to hear how much better the KGBHSE will sound above my Woo GES maxed.

Sherwood's SRM-T1 that you are using was really nice when he brought it over a couple of months ago, and sounded almost identical to the GES prototype but it bested the GES in the bass with at least 2 db more low bass. Later I could hear the improved bass and transparency in my maxed GES vs the prototype, but the total power is still about the same. So, I'm sure it wont come close to the Blue Hawaii for the O2. Plaidplatypus liked the maxed GES with the SR-Lambda more than any other stat amp he's had, including his old KGSS, but didn't like the O2Mk2/GES as much as his old KGSS and O2 Mk1. So, I'm trying to decide between a O2 Mk1 or HE Audio Jade now.

[Sherwood]

I'd wager that the Jade would be a far more radical departure from the o2 Mk. 2 than the Mk. 1 would be.

Hopefully we can get something set up with Naaman to hear his 1.2 when he gets it back. That should give a pretty good approximation of the Jade.

[Elephas]

More O2Mk1 vs. O2Mk2? Isn't everyone tired of this by now?

Well, I'm not.

Does the Mk2 have an annoying mid-bass bump, or does the Mk1 have an annoying lack of mid-bass impact? I think it depends on the listener, of course, and also on associated gear.

With the Aristaeus, the Mk2 sounds more energetic than the Mk1, but with the more dynamic ES-1, the Mk2's mid-bass can seem a bit too emphasized, and its midrange a bit too forward. But without having the Mk1 available to compare, these Mk2 "flaws" would not be so apparent versus other headphones, which are more different.

I would suspect that the Mk2 does reasonably well with the 007 and 727 Stax amps. I've only heard the 007tII a couple of times with a Mk1.

[spritzer]

If you like the normal bias then you have to try a SR-X Pro. I've always found the normal bias Mk3 to be a bit blah so while it does some things well the SR-Lambda is a far better headphone all round. The Pro changed all of this as they do everything better and even have a respectable amount of bass.

On another Jade related matter, it appears that the diaphragm coating has nothing to do with the static problems people are having. After a few PM's and a detailed study of Jade pictures it appears that Mr. He fucked up yet again and it's just plain old dust stuck inside the drivers. Now we all know that dust and ESP's don't mix so there has to be something to stop the dust entering the drivers.

There are only two choices here, solid PVC or Mylar sheets lining the drivers or very fine woven nylon (different types available though). I've seen some other materials over the years but they've also been used for damping at the same time and not only as dust covers (the sheet at the back of the ESP/950 for instance). Stax has used and still uses both methods, usually a PVC film on the + side of the drivers and then several layers of nylon on the back. There were often glass wool damping layers on the back as well so nothing could get past it even on my nearly 50 year old SR-1. When the drivers are operating in open air (like the Omegas and SR-001/3) Stax puts solid PVC sheets on both sides of the drivers to make sure dust will never enter them.

It appears though that the Jade is using a very coarse nylon mesh on the drivers which is far from sufficient to protect the drivers for their entire lifetime. Some may be lucky and never have any issues but others won't be so fortunate. I'll know more once I get a set here but this doesn't look good for a lifetime of service and it is so easy to change with minimal effect on the sound.

[Elephas]

After the long "beta" development period, this problem with the Jade is discouraging.

I was supposed to receive one of the first batch some time ago, but I haven't received anything yet.

[spritzer]

It's grave news indeed and now people are dragging humidity into this which certainly isn't the problem. The bias voltage is far too low for that ever to be a problem.

[Torpedo]

I'd like to see some well measured frequency response graphs, using a competent amp, comparing the O2 mkI to the mkII. Therefore we'd know which of them is more accurate and how our brains "understand" that.

[catscratch]

There's nothing about its sound that's an instant "wow" factor, which is why I originally wrote it off after a 5-10 minute audition at the NorCal 8/25/07 meet (it was amped by the KGSS DX at that meet), but after some extended listening, I can tell there's definitely a lot of subtlety packed into it that only further listening will reveal.

You definitely hit the nail on the head there. The O2 is a very subtle headphone and it never beats you over the head with its technical excellence. This is what makes it so stellar for long-term listening. It's not fatiguing in any way, and it focuses on the whole of the presentation while at the same time giving you the ability to zoom in on any individual aspect of the presentation, while a lot of other headphones will emphasize one thing or another and not really give you a choice in the matter.

[spritzer]

I'd like to see some well measured frequency response graphs, using a competent amp, comparing the O2 mkI to the mkII. Therefore we'd know which of them is more accurate and how our brains "understand" that.

That's easier said then done due to way the Sr-007 frame is designed. Getting the correct fit is a necessity so while that is easy enough to do by ear it's hard to do on a dummy head.

We can leave the subjective part of listening and concentrate on the fundamental rules that govern how the drivers will behave. We can start off with port loading and why it isn't a good idea. Planars are tricky beast and one of the most common problems is the backwave canceling out the bass. With speakers this is usually "fixed" by placing the speakers far from the back wall and by placing something that will diffuse the backwave to the rear of the speakers (look up the Sound Lab "Sallie"). Another way is to increase the size of the baffle as that will allow the speaker to produce deeper bass. The same applies to headphones and why you only see solid earpads on planars as the designers are trying to keep the backwave out and to extend the baffle. The SR-007 is close to airtight (the lovely squeal lets you know about that regularly) so Stax tried very hard to design them like that but then adding a port will let some of the backwave in again and make the baffle "appear" to be smaller. This is clearly audible and will show up on a well setup test.

The other big part is the acoustic loading on the drivers or rather what the driver "sees". This is normally altered by damping but the distance from ear to the driver is just as important. This is why the Sigma phones are so much harder to drive then the Lambda equivalent which use the same drivers and why the height of the A/Mk2 drivers affects the sound so much (also why the Mk1 pads should be replaced regularly). The drivers need to be placed as close to ear as possible or damped heavily. The SR-Omega suffered for the distance with a mild upper midrange coloration but with the SR-007 Stax decided to go into hyper mode and damp the diaphragm more then they had ever done on a full size driver. With the A/Mk2 they should have increased the damping a bit more to make up for the distance but that clearly wasn't the case and is why I question the wisdom of this whole thing. The SR-001/3 is another example of a heavily damped driver. The drivers are the size of the housing but only open on less the a quarter of the whole surface area.

I'd also like to see a detailed comparison of all the Omegas (including the Omega/007 hybrid) but we need more then an FR graph. What won't show up an a simple FR graph is how the chassis handles high volume so a waterfall is also needed. An impedance vs. FQ would also be nice.

[Torpedo]

I agree, however, measurements even very elemental ones but using proper microphone and a decent dummy ear, if made under the very same conditions, would give a hint about the differences among mk1 and mk2 in the midbass and other areas. It's not that much knowing the exact response on each phone, as knowing where the differences take place and their relative importance to the rest of the frequency spectrum response.

[spritzer]

Indeed, knowing the basic measurements should confirm what we are hearing but even getting those basic measurements would involve a lot of trial and error. A small change in the pads is all it takes to break the seal.

[Dusty Chalk]

Does the Mk2 have an annoying mid-bass bump, or does the Mk1 have an annoying lack of mid-bass impact? I think it depends on the listener, of course, and also on associated gear.

Exactly. And on the music.

[Torpedo]

Indeed, knowing the basic measurements should confirm what we are hearing but even getting those basic measurements would involve a lot of trial and error. A small change in the pads is all it takes to break the seal.

Sure. I'm glad I've got a couple of friends with the gear and know how. From time to time I "cheat" them to measure some phones. I've been trying to get the one having the better system to measure the PS-1, R10, L3000, MD5000 and CD3000, but he's very busy so we can't find the right moment. However none of them has critical sealing demands, so they're not as difficult to measure as the O2 would be. Anyway, I own none of both, so no worries

[Asr]

SR-X MKIII impressions update

A crushing disappointment from the SR-X after some extended listening - it's really uncomfortable. The supra-aural design just kills my ears, I can't wear them longer than an hour before having to take them off. Oh well, it's a good thing I always have a backup plan. They do sound really nice though despite the discomfort, if only they were circumaural...

[Fungi]

I heard HC has some skilled nutjobs that can do all kinds of crazy things with headphones and wood.