I have a set of Stax SRA-10S headphones coming into my shop for repair next week.

Does anyone have a schematic or service info ?

Thanks,

Charlie Brewer

Tech Services

Nashville, TN

The SRA-10S and SRA-12S are identical so this applies:

If it indeed a SRA-10S then it is 100V only (that is the reason for the model distinction) so don't run it off 117V like that. 

 

Thanks, this will help a lot !

The SRA-10S and SRA-12S are identical so this applies:

If it indeed a SRA-10S then it is 100V only (that is the reason for the model distinction) so don't run it off 117V like that. 

 

I'll have to wait until the unit arrives next week, but if it is a 100vac unit made for Japan only, there may be a power transformer issue.

So 10S indicates 100vac primary and 12S is for 120vac ?

Any chance of a transformer replacement to make this unit USA 120 vac compatible ?

This is Stax so one never knows but I've never seen a SRA-10S unit that wasn't 100V only.  You would have to have a custom transformer made. 

That schematic is actually not the correct one for the SRA-10S, it is actually a modified schematic for the 10S output board (10S never used 2SC1101 output transistors, it and its big brother the 12S always used Toshiba 2SC1167). 

Spritzer is right, the 12S and 10S share the same identical schematic minus a few quirks here and there with part values.

The actual Stax schematic is in the link I posted. 

Indeed.