spritzer

As most of you know, the new Stax Lambdas suck compared to the older models. This "fact" has puzzled me for quite a while since the same drivers mounted in either the SR-Sigma or the 4070 housings just sing. In the case of the Sigmas, the Sigma 404 out paces the other two Sigma models in every area I can think of by a large margin. To make a long story short, I picked up an old, beaten up SR-404 in Japan to test out some theories. I could have bought a new one but half the fun is to take some old, neglected banger and make them shine again. The first thing I noticed about this set was that the drivers didn't align like they should. They were only a couple of millimeters off but still, they shouldn't be like that. Here are the drivers, mounted to the aluminum baffles, and as can be seen they are a bit crooked. Click the pictures to view larger ones: Next I tried to pull on the driver and see if it would budge. This is the result with only moderate force: The drivers shouldn't move a millimeter in any direction so this wasn't good news. It is clear that Stax have broken off from the old formula (more on that later) so earlier today I ripped the drivers apart and was greeted with this: What you can see here are the remnants of the double sided adhesive that Stax used to use to mount the earpads and the drivers to the baffle. They have now switched to a clear substance but it is even worse as anybody that has had the earpads on a new Lambda come loose can attest to. If the new sets made today are also like this one then these are grave news indeed. Now there is some back story here. The older Stax Lambda/Sigma drivers were fully glued together (as in back stator, the brass rings which hold the diaphragm, the front stator and the metal grill) by a glue similar to polyurethane which is very strong but takes some hours to set. Now Stax have gone through a few variations of these drivers over the last 32 years (SR-Sigma was released in 1977) but at some point they stopped fixing the metal protection grill to the drivers with the slow setting glue and used double sided adhesive pads instead. This is a big deal since this glue is much, much weaker and the driver hangs on the metal grill which is in turn mounted to the baffle. That means any changes to the bond between the metal grill and the driver will change how the drivers dissipate unwanted energy and thus alter the sound quite a bit. The possible solution to all of this is to glue the drivers to the metal grill with some polyurethane and see if it makes any difference. That's exactly what I'm doing now but the process will take at least 24 hours so stay tuned. To finish off for now, here are all the parts cleaned and ready to be glued again:

I'd still buy it. I even have the amp to drive them now after I got my Gilmore Lite with the dedicated PSU. All the Stax phones have the drivers mounted with double sided tape. I'm going to try and find some time today to open up the drivers and start the glue process (takes 24 hours). To reassemble you can use the old adhesive but I would use some new one. The old one should be easy enough to scrape off with your fingers. You really should open up the ES-1 and take some pics so that we can verify what could be a potential issue and how it should be fixed. It would be a shame to see the amp chew up and spit out all those nice output tubes I've sent you. \

Yup, was there ever any doubt that I could pass on a new Stax headphone?

Google is your friend here are there are a lot of LED calculators out there. Just be sure to feed them the correct values and you'll be fine.

Brilliant headphone but I'd rather have the ESP950. \ They might have done it to get a certain sound but it could also just be a way to make the drivers cheaper to make. I'm leaning more towards the latter... As for the resale value, the older units each have a sound of their own so if the SR-303/404 could be made better they would just be another version of that sound. This mod will also not be easy to pull off and certainly not for the faint of heart. I'm sure that they have changed the adhesive (the old one is black and the new one is translucent) but the new one isn't much better as it creates the same type of sticky mess as the old. I much prefer adhesives that make a solid bond with no mess. I've had a couple of new SR-404's here in the last year or so and I heard the dreaded etch but I didn't exam the drivers closely. I only picked up on this as the drivers in this old set aren't perfectly aligned (the adhesive "creeps" with age so the parts move about) and I try to see if it was intentional or not. I'm working crazy hours this weekend but I'll try to take a few pics and glue the drivers.

You need the resistor or the led's go poof.

I would even start drinking again for something like that. The pads are pretty beat up but I can send them out to you if you want them.

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.