For some reason the loop just isn’t giving me any delay in it (I only use it for delay - a Strymon Timeline). The loop used to work fine but I haven’t used the PS100 in over a year. Is it possible the contacts are oxidized or something??? It passes signal, but just no effects can be heard.
CONTEXT: I’m using a brand new Suhr SL15 head (new 15w Plexi). My pedalboard works fine into my Friedman SB50, JCM800, and Suhr PT100. The delay in those loops works normally. I troubleshot this by plugging the guitar straight into the Suhr amp and ran a Boss DD5 delay pedal (battery powered) in the PS100 loop. NO DELAYS. However, with that pedal - if I turn the Boss DD5 “Level” all the way up - I can hear the delays very, very faintly. Obviously I tried the push/push button on the PS100. NO DELAYS. I also plugged the PS100 Send & Return into each other and it passes signal fine. Also, I stressed all the cables to see if that was an issue.
All the cables are good. (I’m very experienced, own Bradshaw rigs, played on major tours, wire up my own stuff, etc.) I sprayed some contact cleaner into both the Send and Return jacks but still NO DELAYS.
I’ve barely used it in the few years since I bought it new. It’s also never been outta the house.
WEIRD ISSUE: When I pull the Return cable HALFWAY OUT of the PS100 “Return” jack I get this weird delay regeneration feedback starting to happen. I can stop this if I push the cable all the way back into the Return jack. So, I know it’s getting some signal of some sort. I’ve never had this issue before.
Thanks for the detailed rundown. First thing we need to establish is whether or not a ground loop is the issue.
Your having experience with complex rigs is a plus, but this is probably going to be a different kind of ground loop exercise than you may have encountered in the past.
Start by checking out the video linked below and follow the recommended steps to eliminate the problems that are probably at the root of your issue.
We’ll be here if you have any follow up questions.
Thanks for this. I watched the video and tried a few things subsequently. I don’t believe this is a ground loop issue. I’ve tried it with multiple heads, Amps, and with a Boss DD5 running on battery in the loop. I’ve isolated variables, changed outlets, flipped ground switches/lifts, etc. I’ve tried it in different rooms in my house, double and triple checking cables, etc.
Also, there’s really not an inordinate amount of hum, just FYI.
It’s probably an issue with the send or return jacks.
When you plug anything into the loop jacks it automatically engages, causing the signal leaving the send jack to return to the power amp via the loop return jack.
When nothing is connected to the loop it automatically bypasses internally.
That means that the loop is working and the loop bypass relay is also working.
By the way, the loop send and return circuitry is passive. It does not require power, has no buffer and does not depend on a power supply to operate. It’s an inherently low impedance design. The only thing that is active is the internal amplifier input stage which is always operational.
The conclusion is that something external is causing this problem.
Have you tried plugging your guitar directly into the return jack?
OK, so upon further review I saw in the manual that the loop is switchable on/off. I didn’t remember that, and I figured when unswitched, the normal state of the loop would be “ON.” It isn’t. It’s “OFF.” So, that was the issue. Most of my other amps the loop is not switchable, and, if it is, there’s a button on the amp to do so. I can turn it on and keep it on with a control function from my board.
