spritzer

If anybody wants to continue the earpad debate then there is no problem for me to cut open the SR-404 earpads I just ripped off a set and open up the SR-007A/Mk2 pads I just got. Any takers...? Anyways, since I had this SR-404 open I thought it was time to find out why the hell this headphones sounds like crap. The drivers are excellent in the SR-Sigma 404 and the 4070 is no slouch either. I put on my detective cap and I think I might have located the issue though it will take some days to prove it. \ It appears that in an effort to save money (or just to annoy me), Stax have stopped gluing the metal protection grill to the drivers with urethane (or what ever it is they use) and just use double sided tape instead. The metal grill isn't really part of the driver but added on afterwards (with the other dust cover on the flip side). It has always been glued with liquid glue, even on the Sigmas. What Stax have done now is simplified the driver design so they are identical on each side then just use some adhesive and mount the grill on that. The adhesive is pure crap as the earpads mounted with it will drift in place over the years and the drivers on this set aren't straight as they should be. This makes perfect sense as the Sigma drivers are mounted backwards so the metal grill is just for decoration and not used to mount the drivers. Therefore the crappy adhesive has no bearing on the SQ and the Sigma 404's shine. I will try to confirm this theory by gluing the drivers and see if they turn out to be something better then they are now. One caveat though. This set is very old so things might have changed. If the experiment works then I'll buy a new set to verify. Ahhhh!!!! But my plan is to annoy Michael as much as I can. You are on the safe to mess up list so all is good. I do remember we were waiting for something but I can't remember what that was...

Me fully content with my rig?? I don't think that will ever happen... The BH I'm building could edge out the BHSE (at least on paper with S22 for the +/-15v, upgraded PSU with massive Plitrons, all silver wiring etc.) but only prolonged head-to-head testing will determine that. I would hang in there and just sell off some of those inferior dynamic headphones instead. If you end up preferring the ES-1 then the BHSE should sell in less then a day and you loose next to nothing. The rub is though if the ES-1 doesn't come out on top then you have something that's worth next to nothing on the used market... \

Happy birthday!!!

Point taken. One thing that might be of interest though, Doug took a picture of the insides of SR-007BL pads for me and they look identical to the normal brown versions.

Perhaps we should stop now Micheal. People really aren't getting the joke...

Just got a Gilmore Lite with the dedicated PSU. Now I'm ready for that local HD800 release party in a months time.

Hmmm so I guess it is elephant bashing time??!!?? There are some SR-007A earpads sitting in customs now and I can show you just how much pleather those Mk1 pads really are...

I've been doing some digging and the new Limited SR-404 uses sheep leather earpads (only where they come in contact with the head like the SR-007A/Mk2) and the cable is 6N silver plated, soft annealed copper with thick silver plating. Needless to say I'm buying one...

It's much worse then crack... I can't resist a good deal or something I know people are looking for i.e. broken SR-202's for 60$ and SRD-7 Mk2's. Well that and spare parts, I needed some some SR-Omega arc assemblies to go with my NOS brown headbands.

Happy b-day!!

Craig runs KuboTen i.e. my dealer...

Awww crap, I didn't need this one with the ISK in the crapper yet again. Still I'll be sure to take one for the team and give it a short, yet brutal review. Craig!!!!!

There are two grades of mylar, C and some other I can never remember. The C here stands for capacitor and is made under stricter QC then the other grade i.e. if it says 1.5um then it is 1.5um within some small range of error.

Heresy!!!! How could for instance Lamm's 100k$ amp be so awesome with mere 1N4007's?

Yup.

I don't regret buying any one of those phones and I've made a lot of people very happy (and addicted) by selling them off. An all DHT electrostatic amp with EML tubes = DR. Wood.

I've been cooking up plans to make a HE90 like headphone (with the real earpads and a similar headband) with ESP950 drivers. They are works of art and Koss didn't fall into the trap, thinner membrane=moar better. The chassis would be beach ply but instead of gluing the drivers to the baffle which is then screwed into the housing, I would clamp the drivers in place. Still it looks like I just won a SR-202 for 3900Yen (pretty beat up though) so there I have some extra drivers.

That was less then half my collection at the time and you should have seen the stack of T1's and other amps. Now it's all gone.

Sure does...

The issue of the amp being sensitive to the impedance of the transducers is a huge one IMO. HFN reviewed the ML Spire in the April 2009 issue and they found the speaker to reach 0.4ohm impedance at 20kHz and it would go even lower into ultrasonic frequencies. This is of course a byproduct of the transformers used in the speakers but shows just how much the impedance changes with frequency. The Quad ESL reached down to 1ohm and up to 30ohm so if we give them a modest 1:150-1:200 turns ratio it is a frightening impedances range (multiply the square of the ratio*the impedance to find the speaker impedance). While ESP's have smaller drivers they are by no means a much easier load. The heavily airdamped stators of the SR-007 and SR-001/003 make things even worse by trapping air next to the diaphragm and thus increasing the impedance of the air. I view the role of high-end to be a straight wire with gain and taking the amp (or any other component) as much out of the equation as is possible. Making sure that the amp can deliver it's full output voltage into any impedance load is a fundamental necessity for electrostatics or the amp will be a limiting factor and alter the sound output. Just listen to a SR-007 or SR-Sigma driven by anything but a Blue Hawaii and you hear how much of a difference maintaining a stable output voltage really makes. All this power isn't cheap so it's no wonder that Stax (with the exception of the T2), Koss or Sennheiser have never come up with an amp that isn't a compromise. Those that are involved in manufacturing know just how cheap those Stax amps are to make given the retail price. Now with something like the BHSE and A-10 there is no retail network to a take a large slice of the price but also no economy of scale. It is far cheaper to make 2000 amps then 20. The A-10 is a very expensive amp though so we should at least expect performance to far out pace something like the 6S4A based Woo GES let alone the PoorMan which will be less then 500$ built and in what looks like two versions (hybrid and SS). Given the data at hand that is far from certain. I've thought about that as well but you would need multiple taps on the secondary to cope with all the different headphone impedances. I sent Justin some of my spare transformers to test the amps with but I don't know if he had any success with that approach.

There is very little Stax related that we don't know of... I do wonder though that the extra angle isn't doing more harm then good and the true magic if due to the very stiff chassis.

Couldn't have said it better myself.

This is what happens when you try to apply logic to the RSA crap. Here we were thinking that Ray might have just a hint of sense and used the high voltage version of the 6SN7 but he used a 300v max tube instead. We bitch about the 6CG7/6FQ7's in the Stax amps but at least they can handle 330v.

That new C-J budget preamp has gotten nothing but glowing reviews, even from HFN which are notoriously picky. I've heard the Pass X2.5 and it was excellent the same as the old Krell units. I even put in a bid this week on an old Stax preamp but thankfully lost. Still I have to buy a SRA-14S one of these days...

More power basically, both voltage and current. It's far from a perfect amp but very hard to beat at that price point.