Stax SRM-X Pro & BPS-600 (Very rare)

[Kacper Uminski]

Hello!

Some years ago, I managed to acquire a Stax SRM-X amplifier. This prompted me to start looking for the very rare BPS-600 battery pack for it. Just recently, I managed to find one for sale in NOS condition, and purchased it promptly.

When it arrived its cells were not working, so I went to a local electronics repairman. He managed to get it working by passing a higher than normal voltage to the cells. I am a total amateur when it comes to electronics so I have no Idea whether this was a good idea or not, but it at least seems to have worked. The unit now both charges by and outputs the proper voltage.

And thus I thought I should post some pictures of both devices here as there is very little on the internet. I am also willing to answer any questions you may have regarding the units.

Stax SRM-X:

BPS-600:

RCA->TRS 3.5mm:

Connected:

Screwed together with rear thumb screws:

Running on battery. (See green LED.)

Manual:

Now I just need to find the special Stax-branded bag, or commission the local tailor to make one. Then I can go on walks in some Lambdas, Sigmas, or 4070's should I locate some.

I hope this post can be of use to someone. Cheers!

 

[staticV3]

Sweet piece of kit!

Just one question: how do you access the RCA ports with the battery pack screwed into the Energizer?

Or is that just for transportation?

Edit:
Ahh I see, that's what the adapter plug is for.
With the battery back connected, both inputs and outputs are on the front panel.

 

[Kacper Uminski]

The battery blocks the rear RCA ports completely. If you want RCA in, you use the included RCA to TRS 3.5mm adapter (See the picture above). The battery was made with portability in mind, not desktop use, so it's not a major issue. The main use case was to carry the package with you in a special bag Stax sold. Probably the most 80's piece of kit that I have ever seen.

I'll happily buy one off you, should you ever find one.