[spritzer]

Have you tried anything besides the WEE?  It's very easy to like something when you haven't tried anything better.  Main reason why people buy the products you listed.  The GES is excellent and doesn't deserve to be there and it's even better now that we've made it fully balanced.  Even lower noise, more bandwidth and better circuit balance.  I doubt Woo will make it that way though as they seem to think one needs to double up the input stage... 
 
Any electronic equipment which has electrolytic caps needs to be serviced after 10-15 years, even if it has never been powered up.  The caps dry out just sitting there and have to be replaced.  Other parts can fail but these are the only ones with such a finite lifespan. 
 
No Stax amp need to matched to any one headphone.  Where on earth did you get that from? 

 

[grokit]

I have read quite a few inquiries/impressions/responses about how certain Stax amps seem to better suited for certain Stax headphones than others, so it seems like I would need to educate myself on the various match ups to make a good vintage amp selection for a given vintage Stax headphone. And as you have mentioned there are no guarantees on how long it will last without needing service unless it's already been totally gone through, and even then. I'm not saying it's not worth it but like any vintage gear it does seem to demand additional commitment.
 
Interesting that you like the GES, as I have read some of your criticisms regarding the WES. When you say fully balanced are you referring to a customized version? Because when I look at the back of it I just see RCAs no XLRs which makes me think it's single-ended. Perhaps you mean something else by balanced?

 

[Magick Man]

The GES doesn't quite have enough weight behind its presentation, so for me it comes off a little lean. The WES, w/ appropriate tubes, has a near-monolithic presence. It's really something else and pairs well with 009s and 4070s.

(I know spritzer doesn't like the WES, but I don't care. )

 

[obobskivich]

Looking at the average price of a used SRD-7 Pro, I'll definitely be keeping a look out for one.

One thing that's odd about my headphones is that the serial number on the amp is only in the 10,000's despite the fact that it looks pretty new and was supposedly bought from Koss only a few months ago.

Seems to work fine enough (sometimes doesn't turn on correctly, but that's rare).

That's odd on the S/N - mine is in the 90,000 range, and was bought in 2011. Never had issues on power-up - always goes "red light, green light" (without the BOOM!, like in the movies) and is ready to rock.

 

[spritzer]

Quote:

I have read quite a few inquiries/impressions/responses about how certain Stax amps seem to better suited for certain Stax headphones than others, so it seems like I would need to educate myself on the various match ups to make a good vintage amp selection for a given vintage Stax headphone. And as you have mentioned there are no guarantees on how long it will last without needing service unless it's already been totally gone through, and even then. I'm not saying it's not worth it but like any vintage gear it does seem to demand additional commitment.
 
Interesting that you like the GES, as I have read some of your criticisms regarding the WES. When you say fully balanced are you referring to a customized version? Because when I look at the back of it I just see RCAs no XLRs which makes me think it's single-ended. Perhaps you mean something else by balanced?

 
The Omega's need more power than most of the Stax amps are designed to provide so some amps work better than others.  Doesn't mean the other amps won't work, just a bit out of control at the extremes. 
 
It's just as likely that a new amp dies an early death as the old ones give up the ghost.  Infant mortality rate is common in all electronics and that's why we run things after the build is finished and do power cycles to make sure nothing happens.  Bottom line is, vintage gear can break down but if it is maintained then it should last for a long, long time.  New and new-ish gear can also break down just as easily. 
 
The GES is a nice design and the WES is basically just a butchered GES but done without a clue in the world.  It's not more powerful in any meaningful way and is just an attempt to use larger tubes and to make it fully balanced.  I would argue that the WES isn't fully balanced as it's essentially quad mono so the channels can drift and with no way to adjust for that. 
 
My GES was built by me earlier this year as a proof of concept and I had an extra chassis/transformer.  It's fully balanced so XLR inputs or just ground the - leg for RCA.  It's so small though that I had to use mini XLR's which are a bit of a pain.  I also a built a fixed version of the WES to show owners how they could rewire their amps for far better performance. 

 

[Taowolf51]

Quote:

That's odd on the S/N - mine is in the 90,000 range, and was bought in 2011. Never had issues on power-up - always goes "red light, green light" (without the BOOM!, like in the movies) and is ready to rock.

 
It's very odd, especially considering the fact that it looks pretty damn new (I even opened it up, looked new inside as well).
 
It's not a huge deal, it sometimes goes flick on > red light > no light. Then after I switch it off and on again, it works great. It's happened maybe twice so far; may get Koss to take a look at it after I get my D7000's back.

 

[milosz]

I use my ESP-950's on a Stax SRM-T1, sounds good to me.
 
I used to have an SRM-1/Mk2  which was also very nice. Sound was quite similar to the SRM-T1  but I thought the SRM0T1  was just a little more refined, so I sold the SRM-1/Mk2.
 
I am not sure if the sound of the SRM-T1 ACTUALLY was more refined or I just THOUGHT it was. Hard to do a real A/B between the two.
 
Anyway, I have only the SRM-T1 now, and I like it. I'm sure some of the newer top-of-the-line Stax amps are better, but the SRM-T1  is pretty darn good.  

 

[disastermouse]

This thread was started on my birthday in 2011.  I take this as a sign that I should buy these!

 

[singh]

Quote:

This thread was started on my birthday in 2011.  I take this as a sign that I should buy these!

very good
 
just so you know, there are only 365 ( / 366) days in an year.
 
waiting for your impressions.

 

[bobusn]

Hi folks!
 
Note these are up at gdgt. Owners, have fun with, "I have it!"
 
http://gdgt.com/koss/esp950/

 

[ho1ysword]

Milosz, I want to thank you for the detailed impressions and information you provided in this thread. You helped me decide to take a risk and purchase an ESP950 system without hearing it first, and I'm very glad that I did.

All frequencies are produced very well -- mids and highs especially are effortless and transparent. The only system I've heard like that was based on a SR009, so I suppose that the "electrostatic clarity" is similarly present in these headphones, at 1/10th the cost. How the hell Beyerdynamic can convince people to buy their Tesla line with a set like these on the market I'll never understand.

Again, thank you for your contributions to this community!

 

[RedBull]

T1 convince people to buy with their bass and soundstage depth.
I am not convinced tho

 

[vaed]

These cans have definitely piqued my interest, and I've been eyeing amazon for a while for a price drop. Is there anywhere else I should be looking if I wanted this renowned $650 price tag?
 
Also, this'll seem a bit random, but I'm looking into this can and the HE-4 for my next purchase, as they've both been reccomended to me as superb metal (music) headphones. I don't suppose anyone can compare them? 
 
milosz' past comments have been very helpful, however, so thank you!

 

[jazzerdave]

Quote:

These cans have definitely piqued my interest, and I've been eyeing amazon for a while for a price drop. Is there anywhere else I should be looking if I wanted this renowned $650 price tag?
 
Also, this'll seem a bit random, but I'm looking into this can and the HE-4 for my next purchase, as they've both been reccomended to me as superb metal (music) headphones. I don't suppose anyone can compare them? 
 
milosz' past comments have been very helpful, however, so thank you!

 
If you can wait, they will drop.  I'd say it's a pretty strong bet that they'll drop to ~ $600 or so when Black Friday comes around again this year.

 

[milosz]

Quote:

 
If you can wait, they will drop.  I'd say it's a pretty strong bet that they'll drop to ~ $600 or so when Black Friday comes around again this year.

 
 
ESP-950's go up and down in price. Not sure why. I know Koss had some financial problems after one of their executives embezzled $34 million ( see http://www.nbcnews.com/id/40245372/ns/us_news-crime_and_courts/t/ex-koss-exec-gets-years-million-embezzlement/#.UWuxfLWPPyk )  and so maybe production of ESP-950's was slowed or stopped for a while, and you know, with the whole production / distribution pipeline thing maybe the ESP-950's were somewhat in short supply for a while.  I know Koss cut back hours for some employees for a while until they recovered from the loss.
 
Also, sales of high-quality headphones have been increasing steadily over the past 5 years, and so maybe we've got a pure supply-and-demand thing here.