The Stax Thread III
May 30, 2020 at 6:18 PM Post #18,648 of 25,261
The T1 series and some SRM-006t & SRM-007t's had normal bias available. You can also find normal bias on some very good third-party amps. Or possibly have someone modify an amp to provide normal bias, not a difficult mod for someone who knows what they are doing.
 
May 31, 2020 at 3:28 AM Post #18,649 of 25,261
May 31, 2020 at 8:02 AM Post #18,651 of 25,261
Mjölnir Audio in Iceland has several models with regular bias, expensive gear though.

A more economical option would be having an electronics tech modify a Stax amp to provide normal bias. This is just changing several resistor values so the costs should not be outrageous. If you have any interest in building your own there is an active DIY forum over at Head-Case. They have half a dozen or more amp builds with printed circuit layouts available some of which are truly TOTL designs. Sometimes you can also find a regular there willing to build an amp to order.
 
May 31, 2020 at 8:17 PM Post #18,653 of 25,261
Mjölnir makes high quality gear, this is their KGSSHV amp with normal bias from their website. There is at least one other company whose name escapes me at the moment (try Google). A good start would be contacting Mjölnir (@spritzer here), he might be able to provide normal bias for their other models as well. Ask him if that customization is available.


KGSSHV.jpg
 
Jun 1, 2020 at 5:44 AM Post #18,654 of 25,261
Resolved the issues I posted earlier. Safety resistor and CSS mods to my 006T + capacitor replacements finished and now I’m toying with the further mod involving 6S4A‘s. The lingering thought I have is what is/are the benefit/s to be derived from this and its extent. Any thoughts/advice would be very much appreciated. My knowledge of electronics is rudimentary at best, so just in case I go down this path, if there is anyone out there able to provide advice, or even better, a drawing or photo of the board mods for these it would also be greatly appreciated.
 
Jun 1, 2020 at 9:06 AM Post #18,655 of 25,261
@astrostar59 Thank you. I am not sure why your post did not show until later.

@ired I think those are all pro bias. It is possible that he would modify one to normal bias if requested, but I do not see why someone would want an amplifier with only a normal bias socket.

In any case, I am not trying to buy an amplifier now. I was merely wondering what commercial products there have been.
 
Jun 1, 2020 at 7:06 PM Post #18,657 of 25,261
Just to temporarily resurrect the previous flame war on amps...

I did eventually buy the 353X and not one of the more powerful amps. The main reason for this was just space on the side table in my living room where I wanted to put it - and I want to preserve my hearing by not turning it up too loud. I'd still consider buying something more powerful in the future - maybe when the next Stax flagship comes out.

Simple question... I expect even the advocates of more powerful amps would agree that if you listen at very low volumes there wouldn't be an audible difference (?) I don't put my 353X any higher than 6 (out of 10) volume and 5 on louder tracks. My wife, who's done less listening than I have, will listen on a 4 (I wish I'd pushed my hearing less...) Question is - can you say how hard you would need to push a 353X before it would be outperformed by an amp with more 'juice'? Would this point be reached at volume 6/10?
 
Jun 1, 2020 at 8:38 PM Post #18,658 of 25,261
Glad to hear that you fixed your 006T. Could you please tell us what the problem was, how you found and fixed it, and what the proper specs for R48 are?
Thanks for having a look. The problem was me; used incorrect range on M.M. Should always start at maximum and work back. I didn't worry about recording R48 value after I measured it, but from memory it was 5mohm.
 
Jun 2, 2020 at 1:10 PM Post #18,659 of 25,261
Just to temporarily resurrect the previous flame war on amps...

I did eventually buy the 353X and not one of the more powerful amps. The main reason for this was just space on the side table in my living room where I wanted to put it - and I want to preserve my hearing by not turning it up too loud. I'd still consider buying something more powerful in the future - maybe when the next Stax flagship comes out.

Simple question... I expect even the advocates of more powerful amps would agree that if you listen at very low volumes there wouldn't be an audible difference (?) I don't put my 353X any higher than 6 (out of 10) volume and 5 on louder tracks. My wife, who's done less listening than I have, will listen on a 4 (I wish I'd pushed my hearing less...) Question is - can you say how hard you would need to push a 353X before it would be outperformed by an amp with more 'juice'? Would this point be reached at volume 6/10?

I had an SRM-323S (353X without the balanced connectors) and never went beyond 3, mainly around 2.5. This is with SR-L300. Going from the SRM-323S to a NAD C275BEE stereo amp with Mjolnir Audio SRD-7 transformer was a noticeable difference, mainly in the low end presence and an overall fuller, punchier sound. Immediately put SRM-323S up for sale after the comparison...
 
Last edited:
Jun 2, 2020 at 4:21 PM Post #18,660 of 25,261
I got a good price on a used SRM 006t & SR-404. If anyone is interested in comparisons to other Stax headphones like the new lambdas or 007, I'll be happy to provide my subjective opinions.
 

Users who are viewing this thread

Back
Top