Stax SR-009 Channel Imbalance Trouble / Driver Problem?

[spritzer]

Any changes in heat where the headphones are stored? 

 

[chinsettawong]

The SRM252 isn't a bad amp at all. 

 

[shipsupt]

I'm pleased to confirm your guess was right! The problem is the energiser, no issue with the 252! Which actually doesn't sound all that bad if I'm honest. The 009 are more than enjoyable even driven by this little cheap thing

 
Well, not "happy" that you've got an issue with your amp, but happy your 009's are fine.  Hopefully just at tube or something simple.  Good luck, an enjoy that little guy in the mean time.

 

[complin]

Yes the 252 and its predecessors are somewhat of a bargain amp wise for the easier to drive Stax's. Sound pretty damn good to in relation to its price and much underrated by some who think you have to pay mega bucks for something respectable.
If i remember correctly Spritzer modded one of the earlier version to accept mini xlr balanced inputs 

 
Quote:

I'm pleased to confirm your guess was right! The problem is the energiser, no issue with the 252! Which actually doesn't sound all that bad if I'm honest. The 009 are more than enjoyable even driven by this little cheap thing

 

[spritzer]

The one I modified has a redesigned power supply, TKD volume pot, higher rail voltages amd RCA or XLR selection on the back.  It was a great little amp and fun to compare it against Kevin's T2DIY... 

 

[carbonfet]

Well, I've found out my 009s have an imbalance. The left channel is about 2dB quieter than the right. Thankfully I've been able to adjust for this on my DAC but I wouldn't call that a permanent solution. The serial number is 2275.
 
Anything I should try first to see if the imbalance goes away before shipping them back to PJ?

 

[spritzer]

This is a charge issue so it could just go away on its own but there is no way to know when.  Most likely the conditions the phones will see when being shipped back to Japan will clear up the issue and Stax will find nothing wrong with the set.  This has happened to an almost dozen sets now. 
 
This will be a problem with 009's and there is nothing Stax can do to prevent it.  Just the nature of the beast. 

 

[shipsupt]

Have you been able to confirm that it's the headphone by trying other headphones with your amp, or another amp with these headphones?
 
Unplug the headphones and short the plug with your fingers to discharge them. Check and see if they are still unbalanced.
 
If you haven't already let them play for a very long time (like over a week) without interruption at decent volume levels.  
 
That's the easy stuff you can try.  
 
Many pairs have been sent to STAX and returned with no "repair" made, but the imbalance gone... seems a plane flight is also a good fix, but not very practical!

 

[realmassy]

Not cheap either, if you have to fly to Japan

 

[jgazal]

Does 2 db difference mean imbalance?

 

[carbonfet]

A bit of an update: I've remeasured each driver using a different method and the imbalance seems to have gone. Either these or my earlier measurements were incorrect (certainly possible) or the imbalance had cured itself since.
 
Maybe I'm going slightly mad.

 

[realmassy]

It's good to know that everything is OK! Especially given the PITA to ship them back in Japan

 

[Clsmooth391]

I purchased the 009s a good few months back but have only managed to set them up now (long story). They are better than any others I have tried and that includes the SR-007 mk1, HD800, LCD 2&3. 
 
I am getting intermittent imbalance issues when I first use them where the right side is louder. Most of the time this seems to go away by letting the headphones play for a few minutes at moderate volume. Definitely a little worried. Has anyone else had this issue or can explain why it sometimes starts off like this and then seems perfectly balanced?

 

[Nitori]

lol in my case (where i had to send it back for repairs) it was the other way around
 
the imbalance got worse the longer it played
 
what amp are you using?

 

[Clsmooth391]

  lol in my case (where i had to send it back for repairs) it was the other way around
 
the imbalance got worse the longer it played
 
what amp are you using?

 
The SRM-717. The way it happened with you seems like the pattern with others. I know they charge so much to fix outside of warranty and I still have over 6 months left. Don't want to take any chances but if I do send it back and due to the intermittent nature of the problem they make not test extensively and send them back. It's only been a couple of days so will keep a very close eye.
 
I called the reseller (Elusive Disc) and informed them of the problem but said I will monitor for a little while. Regardless, they are contacting the Stax rep to inform him and get the process started.