The Headcase Stax thread

[dvse]

I don't really believe that any synergistic amp will make the Mk2/A sound better (or rather as it should) but I have been thinking about the problem and I have a theory. The only two things that really are different with the Mk2/A is the port and the distance from the drivers to the ear. While the pads are different in shape then the sound should be more similar to the SR-Omega/007 hybrid which isn't the case due to the similar pad design. That only leaves those two factors and with the port plugged it's probably the distance between ear and driver that is causing some unwanted reflections in the larger pads.

I've tried the SR-007A with old pads and it really didn't make much difference. The shoutiness was still there in full swing. Maybe there is something wrong with this set? I would not at all be surprised if there is less consistency in assembly than before (assuming that the problem would affect both drivers to the same extent).

I suppose you could try moving drivers from the SR-Omega enclosure to that of SR-007A, but soldering the tiny leads looks like a big pain.

[milkpowder]

Fucking fuck. Ok, thanks guys. Dan, I have a slight suspicion that you are right on the tubes. Since I'll have the 007t opened up, what tubes should I throw in there? And what are my options?

Tachikoma, I also think you're right. Maybe some of the old foam got in there? How do I reseal?

Hmm... Is it possible to take apart a lambda driver? The plates look like they were glued together. I guess as long as you manage to glue them back together...

Tube-wise, the 007t runs on four 6CG7s. The RCA cleartop variant is quite popular. Raytheon and Sylvania are two others...

Mmmm, its unlikely that its the tubes, I've heard the same symptoms on most of my vintage staxen (non-lambda, though).

Reseal was a poor choice of words, reassemble more like =P I use a vacuum cleaner (very, very carefully and with the membrane taken out.) to get the dust out of mine... but a weak USB vacuum should do the trick. You can also gently rub the membrane with some PVC wrap, just in case the dust is stuck onto the membrane.

Sounds like a bit of dust to me too, but I would be extremely careful sucking dust out with a vacuum cleaner. One slip and you'll need replacement stators:o

[Tachikoma]

Hmm... Is it possible to take apart a lambda driver? The plates look like they were glued together. I guess as long as you manage to glue them back together...

I've never done it before But since Spritzer has... I'll assume that it is possible.

[spritzer]

Ugh. The right channel on my Sigs is misbehaving. Intermittent static coming through. Right now, if I had to guess, it sounds like there is some issue with the cable at the earcup because the static problem is occasionally reproducible when I move the that section of the cable. However, the problem occurs on its own also. When I say "static," it sounds like the right channel is making, uh, smooching noises. Sorry, that's the only way to describe it.

Diagnosis (of the phones)?

This could be due to dust but the cable would be my first guess. The drivers are a pain to work on so open up the phones and swap the cable around to the other side and see if you can reproduce it. The wiring for Stax cables is always the same so out of the 3 wires to each side, the one with the printed line is +, the one in the middle is the bias and the last one is -.

I've tried the SR-007A with old pads and it really didn't make much difference. The shoutiness was still there in full swing. Maybe there is something wrong with this set? I would not at all be surprised if there is less consistency in assembly than before (assuming that the problem would affect both drivers to the same extent).

I suppose you could try moving drivers from the SR-Omega enclosure to that of SR-007A, but soldering the tiny leads looks like a big pain.

But did you also move the spring from the Mk1 over to the A? Looking at the phones side by side then the spring is very close to base plate on the Mk1 but it sits nearly 10mm away on the A. The pads clearly stand out a lot more on the A/mk2, much more then either the SR-Omega or the SR-007. Increased driver/ear distance is never a good idea with planar phones.

I got "our" set () back last night and pushing them towards the head seems to calm the midrange but the port mods makes it hard to easy A-B comparisons and I don't have much time to focus on this.

I've never done it before But since Spritzer has... I'll assume that it is possible.

It is possible but takes an extremely steady hand and sharp razorblades. Use a large blade to separate the stators from the bias charge ring (brass ring). Do not try to separate the two brass pieces as that's where the film is glued. When the diaphragm and stators are apart you need to clean off all glue residue with a razor blade, 2mm from the diaphragm. Needless to say, one slip and it's all over. Do that and the drivers can be glued together again but the right glue is crucial, so no super glue or epoxy crap. A special rig is also needed to glue the drivers in and lest them sit for 12-24 hours until the glue has settled.

[deepak]

Does the SR-007A/MKII have that glorious metal bar that goes across the driver like the SR-007 MK1?

[spritzer]

Does the SR-007A/MKII have that glorious metal bar that goes across the driver like the SR-007 MK1?

Yup, that's the spring. It's nearly flat on the Mk1 but not so on the new model.

[Dusty Chalk]

...smooching noises...

Isn't that a classic case of the electrostatic "fart"? I thought this was the result of having too good a seal?

[spritzer]

Isn't that a classic case of the electrostatic "fart"? I thought this was the result of having too good a seal?

That would only be the case for the SR-003 or the SR-007 mk1 where such a seal is needed. If a Lambda does something like this it is bad news indeed.

[The Monkey]

This could be due to dust but the cable would be my first guess. The drivers are a pain to work on so open up the phones and swap the cable around to the other side and see if you can reproduce it. The wiring for Stax cables is always the same so out of the 3 wires to each side, the one with the printed line is +, the one in the middle is the bias and the last one is -.

spritzer, these are not plugs, correct? In other words I would need to resolder the cables?

[faust3d]

That would only be the case for the SR-003 or the SR-007 mk1 where such a seal is needed. If a Lambda does something like this it is bad news indeed.

Hmm, when I press my Lambdas, all of them, to my head I have this fart sound happening, same as on S-001. So I guess it is possible to have this with Lambdas. This happens when I sweat a bit and the pads are sticking to my head.

[spritzer]

spritzer, these are not plugs, correct? In other words I would need to resolder the cables?

Correct. It's easy to do but always cover the drivers with a piece of cardboard or something when soldering as a stray drop of flux can damage/destroy them.

[Dusty Chalk]

That would only be the case for the SR-003 or the SR-007 mk1 where such a seal is needed. If a Lambda does something like this it is bad news indeed.

The Lambda's are the boxes that angle the speakers towards the ears more like speakers, right? Yeah, you're right, that shouldn't instigate the "Stax squeak", there's no way there's that good a seal there, right? So what causes the Stax squeak again? I realize it's the seal, but what is the seal doing, because it sounds amplified...perhaps there's a different cause, but the same result that is happening?

[spritzer]

The Lambda's are the boxes that angle the speakers towards the ears more like speakers, right? Yeah, you're right, that shouldn't instigate the "Stax squeak", there's no way there's that good a seal there, right? So what causes the Stax squeak again? I realize it's the seal, but what is the seal doing, because it sounds amplified...perhaps there's a different cause, but the same result that is happening?

The Lambda frame is the same one in use on the SR-x0x line and is the basis of the 4070. It's the Sigma which has the drivers perpendicular to the head. I posted a picture of one a few pages back.

The squeal is caused by air trying to escape from the airtight (ish..) space next to the ear due to changes in pressure. It will also present as a suction noise when they are trying to draw air into the space. It's the diaphragms (all 3, 2 dustcovers and the mylar unit which produces sound) which get pushed around to try and let air in and let it escape. None of the older phones had this problem as they all leaked some air, under the earpads, around the drivers etc. so Stax installed a port on the new SR-007 Mk2/A to went the space and eliminate the noise. It also produced mad midbass which they thought was an improvement but IMO is was a very, very bad move.

[deepak]

My experience is the SR-007 MK1 farts and the Lambdas squeak (moving plastic parts)

Fortunately the Omegas only fart when I deliberately break the seal by taking them off, and not when I'm moving around.

The Koss do neither.

[hirsch]

My experience is the SR-007 MK1 farts and the Lambdas squeak (moving plastic parts)

Exactly so. The Stax "squeak" on the Lambda series can be eliminated by putting a little bit of silicone grease (use 100% silicone grease to avoid possible damage to plastics) at the hinges between the headband and the earcups.

[spritzer]

Exactly so. The Stax "squeak" on the Lambda series can be eliminated by putting a little bit of silicone grease (use 100% silicone grease to avoid possible damage to plastics) at the hinges between the headband and the earcups.

Talcum powder (or something like that) is what Stax uses and it's great, especially for the fork mount.

[Tachikoma]

That would only be the case for the SR-003 or the SR-007 mk1 where such a seal is needed. If a Lambda does something like this it is bad news indeed.

The SR-Xmk3 farts a fair bit =P

[catscratch]

The squeal is caused by air trying to escape from the airtight (ish..) space next to the ear due to changes in pressure. It will also present as a suction noise when they are trying to draw air into the space. It's the diaphragms (all 3, 2 dustcovers and the mylar unit which produces sound) which get pushed around to try and let air in and let it escape. None of the older phones had this problem as they all leaked some air, under the earpads, around the drivers etc. so Stax installed a port on the new SR-007 Mk2/A to went the space and eliminate the noise. It also produced mad midbass which they thought was an improvement but IMO is was a very, very bad move.

What also drives me up the wall is that the very few professional reviews on these headphones out there haven't mentioned anything about it. Stax need feedback that they screwed up the design and that there are people out there that think this version sounds worse, because given track history, we may not see another revision of the O2 for a very long time.

Or maybe the added midbass is precisely what a lot of customers want? I can't really see this being the case since it's not like the O2 was ever deficient in the bass to begin with (I think?).

And, it's not as if this current iteration of Stax can't design a proper headphone, since they've given us the original O2 and the 4070.

P.S. It's not exactly that I'm yelling that the sky is falling here as the Mk2 is still one of the best heapdhones I've ever heard. I just don't understand the need to step back and sonically compromise, since I never heard the fart to be a major problem for anyone.

[The Monkey]

I can't stand the thought of opening up the Sigs. Maybe if I ignore it, it will go away. Y'know, the adult way of problem-solving.

[spritzer]

The SR-Xmk3 farts a fair bit =P

Every electrostatic makes some noise when forced but very few make that squealing sound due to their design. The He90 is probably the worst with the "peeling " sound though...

What also drives me up the wall is that the very few professional reviews on these headphones out there haven't mentioned anything about it. Stax need feedback that they screwed up the design and that there are people out there that think this version sounds worse, because given track history, we may not see another revision of the O2 for a very long time.

Or maybe the added midbass is precisely what a lot of customers want? I can't really see this being the case since it's not like the O2 was ever deficient in the bass to begin with (I think?).

And, it's not as if this current iteration of Stax can't design a proper headphone, since they've given us the original O2 and the 4070.

P.S. It's not exactly that I'm yelling that the sky is falling here as the Mk2 is still one of the best heapdhones I've ever heard. I just don't understand the need to step back and sonically compromise, since I never heard the fart to be a major problem for anyone.

It is a very good headphone indeed but it's simply not good enough in my book compared to the original. I do believe that Stax made a blunder here and the faster they realize it the better but all professional reviews will just tell us what we know i.e. that this is the best production headphone with no comparison to the older model or a SR-Omega.

Since you brought up the 4070 then it isn't a well known fact but there are two versions out there, the ones produced in 2001-2002 and those made after 2002. The original design didn't allow for the earcups to fully swivel and that made the phones unsuitable for a large number of users. Stax shaved a bit off the housing and the problem was solved.

If you read the pamphlet for the Mk2 then the extra bass response is noted but said to be due to the earpads (more solid material so certainly possible) so it could be that Stax wasn't aware of any problems and the distributors think that it is all down to nonsense like burn in. I simply can't believe that this mess of a midrange was done on purpose as it is not linked to the port issue. I really need a second SR-007 Mk1 to use a basis for the mods to see if this can't be reversed. Anybody have a Mk1 BL they want to get rid off...?

I can't stand the thought of opening up the Sigs. Maybe if I ignore it, it will go away. Y'know, the adult way of problem-solving.

Ignoring something is always my first choice but if you can make the problem appear and disappear by wiggling the cable then it is time to buy a new SR-303 cable.

[Dusty Chalk]

I just don't understand the need to step back and sonically compromise, since I never heard the fart to be a major problem for anyone.

First of all, I hate the squeal. I find the headphones unlistenable for lengths of time for this reason alone.

Secondly, I think Spritzer was implying that they did it to add midbass, not to fix the fart.

[spritzer]

First of all, I hate the squeal. I find the headphones unlistenable for lengths of time for this reason alone.

Secondly, I think Spritzer was implying that they did it to add midbass, not to fix the fart.

They added the port to remove the fart problem and brought along with it no deep bass and a large midbass hump. I'm sure that some compromise could be found through damping where the ear chamber can breath but it doesn't kill the bass.

[thrice]

I'm not associated with the seller:

AudiogoN ForSale: Stax Electrostatic Sigma Professional

Sigma Pros for sale on A'gon

[Voltron]

I've never heard Sigmas. What do people think about $800 obo as a price point?

[Dusty Chalk]

They added the port to remove the fart problem and brought along with it no deep bass and a large midbass hump. I'm sure that some compromise could be found through damping where the ear chamber can breath but it doesn't kill the bass.

Okay, I stand corrected.