spritzer

I vote for throwing a gallon of petrol over the lot and lite it on fire. Slee makes RSA seem well designed by comparison...

The UK service guys have been pretty responsive and helpful in the past so it is well worth it to contact them. I would stay away from pretty much all of the cable guys since they have zero soldering skill. Soldering these cables is no joke as you are soldering directly to a high precision driver and excessive heat, flux castoff etc. will destroy the drivers. There is a reason why I use a soldering station with very high temperature stability...

It's right next to the (ineffective)strain relief on the cups.

Stax have been laying down the law as of late so sourcing parts is getting more and more difficult. If you can get a replacement cable then the swap is easy enough but the common rules about working up close and personal with electrostatic drivers have to followed to the letter.

50Hz sounds plausible to me but I have no equipment to measure this stuff and Stax would never release any info on this. As for the voltages, are you referring to just normal levels (70db is what most people seem to be running at) or something much higher like 100db?

I'll do that later on but these should be all but identical to the 404's. The cable is a much better fit to the gray housing though so I think they look a bit nicer. I'm a bit OCD so these are just a little bit special... There are no nasty double sided adhesives used to attache the drivers to the housing, it is all done with polyurethane. I even used it when I attached the metal grill to the other side of the driver (when moving Lambda drivers over to a Sigma chassis they have to be taken apart and the metal grill moved to the other side). Same deal on the SR-Lambda I made from the leftovers....

The older Stax Lambdas also have woven dust shields on the back (which is what Sennheiser copied) but these were only effective back when there was a damping layer to seal out the dust. The Lambda Sigs were badly affected by this. The LNS (and all later models) feature PVC sheets on both sides of the drivers.

I highly recommend you add plastic sheets on either side of the HE60 drivers to keep the dust out. While no 'stat driver likes dust the HE60 can go a bit nuts...

Screw the playback equipment, how about using an amp that is even somewhat neutral? The Sigmas can sound truly odd at times but that midrange is to die for. Reading something on HF? You must be mad... While the data we have are just small pieces of a much larger picture we can extrapolate from it and get somewhat plausible results. There is also a way to calculate the force but my brain is just too fried to even contemplate thinking about it...

It's been an interesting last couple of hours comparing the SR-009 to the SR-Sigma/303 I finished today. The Sigmas may be highly colored but they still manage to sound better then most headphones ever made. If there were any large scale excursions then the distortion would be much higher. To me the 4070 is a bit of a compromise and certainly hasn't got any extra detail over a good Lambda and far less than any of the Omegas. The working parts are stock SR-404 but with the 4070 Stax did the same trick as with the SR-X Mk3, cancel out part of the bass by bleeding it away which opens up the upper frequencies. They certainly are a monitor headphones in every sense of the word but still suffer from the same issues as all Lambdas by having the driver just hanging off a piece of aluminum by some not so great double sided adhesive...

If the diaphragm was loose-ish then I could see this to be true but once we factor in just how tightly stretched the Omega diaphragms are and the relatively weak force at hand here then any large scale excursion becomes improbable IMHO. Best way to determine this would be via distortion analysis because once you get any large scale excursion in a push-pull driver then the distortion rises quickly.

Happy Birthday Gents!!!!

This one has about 10 years on me so yeah, it is rather old. New soldering station landed today so I'm back in business and as it turns out, the pre and phone stages are nothing like the schematic and service manual. This is truly a very early unit...

Given that the diaphragm doesn't move at all (it just vibrates) then I doubt any run it will add to the impact.

Nice!!!

I unfortunately shipped out the last one a while ago.

It is indeed a huge factor and often overlooked. Even with superbly recorded stuff (SACD rip of Aja) they get quite a bit edgy once the volume is pushed much past 70dB.

A small comparison here... SR-X Mk1 and Mk3 PRO hidden in the back and SR-Sigma 303 sidelined while I repaint part of the chassis... I'm sure my set isn't a lemon since the brightness is tied to volume level same as with the SR-Omega. Many other owners have also reported the same. As for being a power hog, I've only done limited test but yeah, they do like plenty of power. I prefer to use the KGSS over the BHSE for some reason though...

OKI (Metcal) PS-900 soldering station plus spare parts for my broken PS-800.

Happy Birthday Amos!!

Nice work Tyll. I do think that some of the reservations about the 007 could be fixed by adjusting the fit since those arc's are just set to "some" setting. You have a ...ehhh... larger head like me so making the arc's wider would be a good move. It's not a make or break type of deal but it does improve the sound quite a bit. Same deal on earpad placement and indeed their condition. The Mk1 earpads are only good for a few years before foam inside becomes too soft to seal properly. We never said this was an easy headphone to measure... I have my own shootout going on but first impressions show that this one is going to be tricky. The SR-Omega/009 are so different in presentation to the 007's that this will have to be a long comparison. Quick changes will always be in favor of the more open sound similar to why the HE90 is so well liked in short burst. Hell, first time I plugged the 007 Mk1 in I thought it was broken and wondered why it sounded strange. Then I remembered what source I was using... It was interesting to plug in the SR-007A and listen to the utterly out of control bass. This is a stock unit save for fit adjustment and the port nonsense is showing it's ugly head. One thing I'm going to give the SR-009 and that it is the most comfortable headphone I've ever used. 6 hours straight aren't an issue and I hardly feel them sitting there.

The amp was utterly fubar when I got it so no measurements possible but the math places it around 13mA. This goes in hand with the schematic I found online. No metal around it except the metal steel brackets used to secure the HV boards in place. Here is a picture of the inside which shows how bloody small this thing is about 30cm long by 17cm wide... Now my bloody soldering station just died...

Now that's what I'd call mafia approved pics!! I've been holding off the comparisons while I finish my backlog of headphones I need to refurbish but it should be soon. Now if some idiot hadn't damaged the paint on this Sigma then I'd have a Sigma/303 to compare against...

AFAIK the SRA-10S is identical to the SRA-12S. The service manual shows no differences aside from what one sees over a long production cycle. This unit is relatively old which is why I'm going totally overboard in rebuilding it. The design is that far off from the old Stax tube amps, in this instance we have just a low voltage SS stages feeding the outputstage which runs off a 640V B+. Simple resistor loading of the output stage so not much anybody can do there and the PSU is a bit too small for my liking. Since I will be ordering a custom transformer for this one I'm contemplating PSU changes. Now the space available is pretty much zero but a simple regulation like the old KGSS PSU should work here and the voltage can be managed simply by regulating each of the two stacked supplies independently. In stock form it is just a 260-0-260VAC transformer feeding a bridge and two stacked 47uf/350V caps. I can easily fit much larger caps so that will be the first step but it is always better to add regulation... As for the SRA-3S, the basic building blocks of the amp maybe similar to the T1 but the circuit is quite different. The T1 is fully DC coupled but the SRA-3S has both input and output capacitors . Now on the amp I have here now I changed all of these (plus all other caps just to be safe) and it sounds just lovely driving this SR-Lambda I just made from Sigma parts.

Happy Birthday Jim!!!