Blatty when guitar vol rolled down?

[soma_hero]

Finished up an 18W Trex and on the Trex channel the amp gets blatty and gated when you start to roll the volume on the guitar back. Full up it sounds fine but when you roll down it starts to cut out/mush up.

18W channel is fine, so it must be something specific to the Trex side. Any usual suspects when this sort of thing happens?

[Stanz]

Intermittent, loose connection? Is the channel selection done with a switch? Signal is weak to begin with at full volume, then when you roll the guitar volume down, it becomes more evident.

My first response was guitar volume pot issue, but if it plays clean on another channel, most likely not. Although, might be a good idea to check the guitar volume pot, give a cleaning, simply to eliminate that as an issue, and gets you some preventative maintenance in on your guitar.

[soma_hero]

The channel switching uses solid state mosfet relays. I think it must be a loose connection somewhere. At full volume the signal isn't weak, it's perfect. Loud and aggressive. When the vol gets rolled back though then it does become evident something is wrong. I'll try and trace it down this weekend.

[John_P_WI]

Usually blatty or sticky sounds happen when a grid leak is not in place. Make sure your channel switching scheme allows a path to ground at the next stage as well as all of the grids have a path to ground whether a grid leak r or vol control etc.

John

[soma_hero]

John, good call. I did install VVR and have coupling caps with grid leaks on the volume controls and input. Maybe i miswired a grid leak before the coupling cap going to the grid. Did that on my Liverpool too. thanks for the tip