• The move to the new server is done. There are some software and database maintenance updates in process. This has us passing the hat around to help out. We appreciate any donations. Seriously, even a dollar helps. The payment page may be found here - https://www.audiokarma.org/support.html

Stax SRD-5 ballast resistor value?

L

li303ve

Member
I’m currently in the process of going through a Stax SRD-5 energizer, which came with a pair of SR-3 New headphones I have. I’ve already replaced the old electrolytic caps, and the whole system seems to be working.

The schematic I found (attached below) shows a 27 meg resistor between the bias supply and the headphones. In my unit, this resistor is a 4.7 meg carbon comp resistor, which has drifted in value to 7 meg.

I’d like to replace the resistor since it’s out of spec, but I’m wondering if I should stick with 4.7 meg or if I should use a 27 meg resistor as in the schematic. Any advice would be appreciated.
 

Attachments

  • srd5-001.jpg
    srd5-001.jpg
    34.9 KB · Views: 20
Register to hide this ad
Since this thread didn’t get any replies, here’s an update for anyone with the same issue who might see this post in the future:

I ended up sticking with 4.7M since that’s what was in my unit originally, and it also appears to be the value Stax continued to use in subsequent normal bias energizers like SRD-7.

I’ve been using SRD-5/SR-3 combo for the last week or so and have not had any issues so far.
 
li303ve said:
Since this thread didn’t get any replies, here’s an update for anyone with the same issue who might see this post in the future:

I ended up sticking with 4.7M since that’s what was in my unit originally, and it also appears to be the value Stax continued to use in subsequent normal bias energizers like SRD-7.

I’ve been using SRD-5/SR-3 combo for the last week or so and have not had any issues so far.
Click to expand...
Thanks for this. I was having trouble making out the value of that resistor on my SRD-5, or finding any schematic. My 4.7 meg had also drifted up to 5.4 Meg, so I'll be replacing that along with the 2, 1mF caps. I am think of using CDK 105TTA160M caps there. Those are 160V direct replacement. Did you go up in voltage at all? Also curious if you replaced your diodes, or left them original. I have extra 1n4007's on hand, which are overkill here, but I think they'd be fine.

I have slight attenuation in one channel that I am trying to balance out. The other resistors look to be in spec and closely matched.

Anyway, you never know when a previously ignored thread will be useful to someone. So thank you again!
 
You must log in or register to reply here.
Back
Top Bottom