I recently bought a Series II bass that came with a rack mount DS-5. The packing job could have been better, and the Stereo/Mono switch broke in transit.

Plugged in, the only signal that's coming out is the bridge pickup (I'd have expected the neck, since I was running from Bass/Mono to my amp.

I'm hoping that I just need to replace the switch — does anyone have a little wisdom to share?

Thanks.

We might need a picture or two.  Are you talking about a standard DS-5 (small blue box) which has been modified to be rack mounted?  Or is your unit a DS-5R?

Are you saying only the bridge pickup signal is appearing at each output?  Any sound from the neck pickup anywhere?

Could you test the 1/4" jack on the instrument to be sure both channels are functioning?

Just some ideas.  Tell us more and we'll give you more ideas.

Jimmy J

It's a DS-5R.

All instruments work fine through a stereo to mono cord. Using the DS-5R set to mono, all I get is the bridge pickup, regardless of whether I'm using the front or rear jack.

Thanks!

So, the switch blade broke off in transit. And it's either stuck in the stereo position or switching the nub of it to mono position has no effect?

Either way, you're only getting one pickup, and its the bridge pickup. Agree, to the extent that it'd be the neck pickup if only mono signal were passing. But I think if it's only getting the bridge signal through... doesn't that indicate...

What's that switch actually do, Jimmy J? 

Have you tested with a different five-pin cable?  Might be that the cable is the issue. 

Replacing the broken switch may shed some light on the issue. 

I hadn't thought of the cable — I'll try another one later today.

It won't solve the issue with the broken switch but if the switch broke in mono setting and you are getting the bridge pickup only it wouldn't hurt to check to make sure the leads to the pickups weren't swapped at the card.

Hopefully swapping cables works until the switch is replaced.

I tried it with different basses, and all of them are bridge only through it. I really hope it's the cable, otherwise there's something really weird going on.

Yes, worth trying another 5-pin cable. Let us know if that changes things.

Greg, that switch just brings the two channels together through summing resistors, just like more recent mono 1/4" onboard jacks. Then it's supposed to send that "sum" to the outputs.

Regardless of the position of the switch, if no bass channel appears at any output it feels like something else is going on. Unlike the stereo onboard 1/4" jack, a DS-5R should not default to either the bass or treble channel. 

Nova, keep experimenting and we'll find an answer soon.

Jimmy J

Tried another 5 pin cable, and I'm still only getting the bridge pickup.

Maybe I should change "misery" to "mystery" in the title here.

The good news is that I'm 40 minutes from the mothership, and have plans to be there in the next month or so.

For a temporary solution, you could remove the switch. Easiest would be if you use it in the Stereo setting, for Mono setting you must use the resistors to mix the signals together.

Quote from: FC Bass on May 31, 2026, 02:19:48 PMFor a temporary solution, you could remove the switch. Easiest would be if you use it in the Stereo setting, for Mono setting you must use the resistors to mix the signals together.

For now, I'm using a Boogieman box that I was hoping I wouldn't need. I've got my fingers crossed that the DS-5R will be easy to fix.

Your DS-5R should be easy to fix as it's not a complicated circuit. If you feel like jumping in you could open it up and post a pic or two. 

Jimmy J

Déjà vu?

https://club.alembicguitars.com/troubleshooting/new-bass-day!!-but-all-is-not-well-with-my-new-series-2/

Quote from: Nova Constellatio on June 03, 2026, 08:09:11 AMDéjà vu?

https://club.alembicguitars.com/troubleshooting/new-bass-day!!-but-all-is-not-well-with-my-new-series-2/

Sure sounds like a similar situation. That little toggle switch is kinda' hangin' out there alone and vulnerable. When I shipped a DS-5R unit to another Club Member a little while back it bothered me enough that I put a block of high-impact foam around it.