The Stax thread (New)

[behwatch]

 
Finally bought my setup after testing many headphones. This is the best I have heard after comparing with HD800, LCD2 rev2, AKG K1000.
 
HD800 is too bright even compared to K702 and CD900st. It is not comfortable to me as the ear foam is too rough against my skin. The imaging is too far that I can't hear the clinking sound of wine glasses striking in "Party Queen - Ayumi Hamasaki".
LCD2 has a too heavy bass that mask out the mids and highs making it difficult for me to hear ppl singing. The bass is also not clean and clear. The imaging is too narrow too.
AKG K1000 sounds plain to me with too light bass.
 
As for the amp, I took 727II instead of 007II as the 007II sounds veiled to me and the bass has no impact. I hear more details through the solidstate amp.
 
The setup is very fast and clean as it lets me hear each piano keys strike independently and not all together in a fast-paced piece like "Trois mouvements de Petrouchka - I. Danse russe". Even the JH13 is not as fast. The vocal is like the singer is beside you singing into your ears. I even found out some songs that the singer has sung out of beat.
 
However the weight of the SR009 is quite heavy and you will need a strong neck to be able to listen to it for a long time unless you keep your head and body upright straight or maybe do some neck training LOL. Another flaw is that the cable is heavy and hard to handle as I need to keep sliding it back up the table when it slids down to touch the floor again.

 

[Anaxilus]

For the sake of curiosity, what amp(s) did you use w/ the dynamic cans?

 

[HeadphoneAddict]

Quote:

 
The SRM-323 is hamstrung by how much it costs to make and it's price bracket so only small heatsinks for the output devices and thus limited current.  It is a remarkable amp for the low price of 800$ and I can't think of any fully balanced amps for dynamics which come close to it in quality.  It's not perfect but still the best Stax amp one can buy for anywhere close to 1k$ new. 
 
The Baldur, Aristaeus, HEV90 and GES all share a very similar circuit layout.  They are different but in broad strokes they are all very similar.  Any reason a GES would sound drastically different from an Aristaeus is that something was wrong with the GES.  It's also not the best idea in the world to use 12BZ7's in this circuit as they are similar but not the same.  I liked both of the GES amps I've heard but Woo have a tendency to mess up any circuit they touch with "improvements".  The 6S4A used in the GES is certainly the best output tube of the lot so the amp should be very good. 

 
I definitely agree that the 12BZ7 Jack sent me didn't sound good with 007 in the GES, while a quad of Telefunken Smooth Plate 12AX7 sounded outstanding.  The 12BZ7 were a bit darker and more closed in sounding.  What bugged me was that my maxed GES didn't sound much better than a basic GES, and I'd wasted about $1000 on the upgrades when tubes made a much bigger difference.

 

[behwatch]

Quote:

For the sake of curiosity, what amp(s) did you use w/ the dynamic cans?

 
Using the pico amp. I know that the amp is not the best to test with. But I heard the hd800s with lehmann audio amp resulting with the same review.

 

[spritzer]

Quote:

Thanks Spritzer. It doesn't sound very good! Why on earth one would like to use that? 

 
People use tube amps here which were considered inferior designs in the 50's so this certainly isn't as bad as that.  When you are messing with EQ there will always be some loss unless you do it all digitally in software.  Not really an option for Stax in the mid 80's and today there isn't enough interest for us to even contemplate a DIY version. 
 
Quote:

What are the specific differences between the circuits of the KGGS and current Stax amps?  A lot of people are shooting from the hip, but I would be very interested in the substantive differences between the various designs. 

 
Biggest issue with any of the Stax amps are the non regulated power supplies.  Only one Stax amp ever had a fully regulated PSU and it's an oddball in more ways than one.  Another factor which they have to deal with is weight and transformer size and heatsinks being the largest contributors to weight.  Cut the standing power of the output stage and you save on both heatsinks and transformer size.  Win, win in that regard but not something we have to think about with DIY or small scale production.  I have a fully populated KGSS circuit board sitting on my desk and it weighs close to 700gr.  This is the lightest part of the amp so add the PSU and a transformer plus the box. 
 
Now a 717 is pretty much just a KGSS but Stax did do some changes to the circuit which makes it less linear than the stock design.  They clearly didn't want the "wire with gain" sound but the end result is just a bit more rounded, not unpleasant at all.  The 727 is a different design, more inline with the SRM-1 Mk2 legacy but with that stupid idea of cutting the feedback line short.  There are plenty of anti NFB people around (99.999% of whom have no idea what they are talking about though) but with a gain of 500 you need NFB.  Not too much but just enough to stabilize the circuit. 
 
All in all I do think the Stax amps are great and they make commercial dynamic amps feel very cheap by comparison.  Most being some opamp based circuit with perhaps a crude buffer or a tube amp a tech from the 50's would know well.  Even the Stax tube amps are good but they are limited by what tubes are out there.  Once they move to the ECC99 exclusively then they will be much better since it can handle the extra voltage. 
 
Quote:

 
I definitely agree that the 12BZ7 Jack sent me didn't sound good with 007 in the GES, while a quad of Telefunken Smooth Plate 12AX7 sounded outstanding.  The 12BZ7 were a bit darker and more closed in sounding.  What bugged me was that my maxed GES didn't sound much better than a basic GES, and I'd wasted about $1000 on the upgrades when tubes made a much bigger difference.

 
Stock polyprop caps are much better than people give them credit for.  Most "capacitor comparisons" you see will be in some sub-par circuit which favors a certain property of the capacitor so those caps will win out. 

 

[ri_toast]

"Only one Stax amp ever had a fully regulated PSU"
STAX SRA-12S? assuming this because you called it an oddball. I don't know, being curious. Plus I'd like the cookie for being correct, an ice cube would also be an adequate acceptable prize.

 

[kevin gilmore]

SRM300/SRM310 is the only stax amp with a regulated power supply.
 
The srmXh,srm212, sr001 are all switchers and could be closed loop
regulated, but are not actually wired for feedback.

 

[schorsch]

Quote:

 
Ah, you were the guy - 5 minutes ahead of me...

 

Dear pachku,
 
I bought mine from a local dealer here in Germany. How much did the Unit on ebay sell for?
 
Regards Georg

 

[schorsch]

Quote:

 
 
Please open it up and take some pics.  I does look a lot like a reverse engineered ED-1 which used a few opamp based EQ networks adjusted for a given target. 

Dear spritzer
 
I'll take some photos on Monday on put them here on head-fi. There are two articles on the HP-1 on the pawel homepage. There is also a picture of inside in one of them.
 
Regards Georg

 

[spritzer]

I've seen that picture but I just want to be sure what we are dealing with. 
 
Quote:

"Only one Stax amp ever had a fully regulated PSU"
STAX SRA-12S? assuming this because you called it an oddball. I don't know, being curious. Plus I'd like the cookie for being correct, an ice cube would also be an adequate acceptable prize.

 
The SRA-12S has a regulated low voltage supply but the HV is just made up of twp 320V filter capacitors stacked.  The SRM-300 is just the SRM-001 amp on steroids so quite the oddball. 

 

[gilency]

How much do they sell for and how does the sr007 sounds with it?

 

[musicman59]

Quote:

 
Finally bought my setup after testing many headphones. This is the best I have heard after comparing with HD800, LCD2 rev2, AKG K1000.
 
HD800 is too bright even compared to K702 and CD900st. It is not comfortable to me as the ear foam is too rough against my skin. The imaging is too far that I can't hear the clinking sound of wine glasses striking in "Party Queen - Ayumi Hamasaki".
LCD2 has a too heavy bass that mask out the mids and highs making it difficult for me to hear ppl singing. The bass is also not clean and clear. The imaging is too narrow too.
AKG K1000 sounds plain to me with too light bass.
 
As for the amp, I took 727II instead of 007II as the 007II sounds veiled to me and the bass has no impact. I hear more details through the solidstate amp.
 
The setup is very fast and clean as it lets me hear each piano keys strike independently and not all together in a fast-paced piece like "Trois mouvements de Petrouchka - I. Danse russe". Even the JH13 is not as fast. The vocal is like the singer is beside you singing into your ears. I even found out some songs that the singer has sung out of beat.
 
However the weight of the SR009 is quite heavy and you will need a strong neck to be able to listen to it for a long time unless you keep your head and body upright straight or maybe do some neck training LOL. Another flaw is that the cable is heavy and hard to handle as I need to keep sliding it back up the table when it slids down to touch the floor again.

 
SR-009 heavy???? Compare to what? Ok, if you compare them to the HD800 I would say yes they are heavier but compared to the LCD-2, LCD-3 or HE-6 they feel like a feather 

 

[behwatch]

Quote:

 
SR-009 heavy???? Compare to what? Ok, if you compare them to the HD800 I would say yes they are heavier but compared to the LCD-2, LCD-3 or HE-6 they feel like a feather 

 
I mean heavy when wearing on head. I have tried lcd2, hd800 and w3000x but not the he-6 and lcd3. it may be the mechanism.

 

[Magick Man]

Compared to the 009s, the big orthos are like balancing a decent sized cat on your head.

 

[jaycalgary]

009's are about the same weight as 007's? If they are that is reasonable. I went to a meet and heard LSD2 and HE500 and they feel at least twice the weight. To me that is a deal breaker.