Relay Issue?

[Charlie Wilson]

Hello all, as anybody knows that has read my posts about my Low Plate Classic I have been struggling a bit with the amp sounding inconsistent and this has been going on for awhile. I tracked some of it down to some vintage pots that I used that were not in the best shape but still sometimes the amp sound great with nice bass and treble and sometimes it sounds dull. Other times it will sound shrill and has no low end at all. I just resolved myself that it was the bad AC were I lived. Tonight I was playing the amp and it sounded OK and then all of a sudden it sounded full and great. I turned the amp off and back on again and it didn't sound as good. I then started eyeballing my OD relay. I ran a jumper from the .02 clean coupler to the master volume and it sounded great again. Has anyone ever had a bad relay corrupt their tone this way? I made me start to think about the fact that an HF taper kills my clean sound when it should be isolated from the clean. Maybe the two are related.
CW

[tubedogsmith]

Not had a bad relay per say but have had a poor connection with the relay board. I don't know how yours is connected but if using eyelets or turrets flow some solder under them maybe.

[Charlie Wilson]

Thanks Tubedogsmith, yeah I touched up the solder joints and I thought that solved it but the smeary rolled off sound started happening again after a little while and if I attach the jumper it clears up. I have noticed in the past that when I first turn on the amp it is nice and gainy in OD mode and then it starts to lose it. The fact that the jumper makes the sound strong again seems to rule out any other issues and points to the relay, I think.
CW

[norburybrook]

Charlie, as I've found out recently intermittent problems are the worst.

Are your relays, soldered to a board or pressed in to those IC type sockets?


I've soldiered mine direct but I can see why using sockets would be a good idea at a time like this.


In fact I have some kicking around and might just unsolder mine as it's out of it's case at the moment and socket them.



Marcus

[Charlie Wilson]

Hello Marcus, I socketed the relays which will make it easier to switch them out. I guess the downside could be stressing the solder joints on the socket taking relays in and out. I still can't visualize what is going on inside the relay to cause the problem I have. I did however pull the relay out, jumper the clean side, and put a straight cap no resistor were I usually have the HF taper and it did not roll any high end off of the clean like it was doing before. There must be some kind of cross talk going on inside the relay. Maybe leave your relays soldered unless you suspect a problem with them. I don't think failing relays is a common problem.
CW

[Charlie Wilson]

Well I took a trip to my local electronics store and got some new relays. It solved the problem and the amp sounds great! I also found a bonus hanging on the resistor rack. Not an amp usable value but still cool.
CW

[norburybrook]

good news another thing to look for then with intermittent problems !


I suppose the relay wasn't making a proper connection then when switched, just like a faulty switch, but hidden.

Marcus