HX Stomp + Grandmeister Deluxe 40 FX Loop = Problem!

[muppeman]

I have come across an annoying problem here. Whenever I use the HX Stomp in the FX Loop of the H&K Grandmeister Deluxe 40, the amp becomes noisier and more prone to feedback on the high gain channels even with conservative gain settings and no boost. This constantly happens, no matter if I I do the 4CM or use the HX Stomp In/Out only in the GM40 FX Loop.

 

I started checking the amp FX Loop with a straight patch cable, different pedals etc. and only when the Stomp is involved, the noise issue arises. So it´s not the amps loop that´s failing

 

I´ve tried switching between Instr/Line levels, different impedances on the HX Stomp input, increasing/decreasing level gain on the In/Out of the Stomp but so far to no avail.

 

Help anyone? Has someone maybe encountered the same problem with other amps?

[rd2rk]

In the FX Loop of my Egnater, it's totally silent.

Of course, I use it 4cm, as it was designed to be used.

What FX are you using? If you put amps and gainy FX - ODs, Distortions, fuzz - in an FX loop it will cause this problem.

Try only using mods/delays/reverbs in the loop. If you want to use gainy fx, use 4cm and put them BEFORE the GM.

 

EDIT - If you ARE using 4cm, you're doing something wrong. See above.

[muppeman]

When I did this testing, no blocks in the Stomp were active at all! It still makes the amp slightly noisier and more prone to feedback even at unity volume on the Stomp (no volume drop when switching the GM40 FX Loop on/off). No matter if I used 4CM or not. Maybe a impedance issue that a buffer can rectify? I´ve tried changing the impedance of the input of the Stomp, didn´t do anything about the problem!