Marshall Valvestate 8240 with Helix fx loop issues

[NecrosisFactorG]

Hi everyone, i hope your'e doing well and stayin' safe.

 

I've got a Marshall Valvestate 8240 (2 speakers with 40w on each, i assume this is an stereo combo amp)  in pretty good conditions, replaced the preamp tube with an EHX 12ax7 valve and it sounds nice, with it's own EQ limitations. But i want to use the fx loop for my Helix LT amp sims. So i went to the official Line 6 youtube video about the cable setup, triying with the FX return in mono from the 1/4" output in Helix at instrument level (tried both instrument and line) but  it sounds like there is  phase cancellation and every amp sim within the Helix sound the SAME. Muffled, dull, no tube amp dynamics. The preset  didn't have any send/return/fx loop blocks, just as the youtube video showed. 

 

Then i investigated and discovered that all valvestates have parallel fx loops (i alwys have the dry/wet knob at 100%)  and it's highly possible that some preamp signal from the valvestate is bleeding to the master power amp. So i tried the 4 cable method, placing a send and return blocks in my chain with an full amp block (i've read that those amps have a nice clean master power amp so i use full amp models in Helix) and it sounded more real, but i still hear the phase cancellation.

 

The Helix amp reacts much better with this setup but i also read that if i'm using the fx mono return i'm only getting one power amp side since it's an stereo combo and this maybe is the cause of the phase issues. I'm getting frustated with this fx loop thing, i'm sure i can unload my rig's full potential, but i would love to hear if someone uses his beloved Helix with an stereo combo SS amp with parallel fx loop and how. I'm about to sell my Valvestate, but i please tell me if it's worth to keep. Thanks for your help

[rd2rk]

I'm guessing here, that the effects knob should be full clockwise, but try it both ways if using 4cm.

Otherwise, just take the Helix L/MONO Out into the Valvestate LEFT RETURN.

 

See below, from the Valvestate manual:

 

MASTER SECTION (8240)
The 8240 has identical features up to item 17, then
as follows.
17. Effects Returns
Jacks for connection from the left and right outputs
of an external stereo effects processor (left return
also acts as the return for a mono effects processor
if used).
18. Effects Mix
For mixing the effects to dry signal. Note - if no
effects processor in line, Effects Mix fully
clockwise will result in no signal.

 

 

[rd2rk]

Sorry, left something out. If you take the LEFT and RIGHT 1/4" outs to the LEFT and RIGHT RETURNS, you should get stereo.

In Helix, you can't have a MONO Block after the final STEREO Block or it will collapse to MONO.

[NecrosisFactorG]

1 hour ago, rd2rk said:

Sorry, left something out. If you take the LEFT and RIGHT 1/4" outs to the LEFT and RIGHT RETURNS, you should get stereo.

In Helix, you can't have a MONO Block after the final STEREO Block or it will collapse to MONO.

(

Thanks for your answers! Yep, i read the Valvestate manual. I'm not really using any stereo effects in the helix, just amps. But my guess is that the valvestate, in the way i plugged everything is not using both power amp sections so i hear the Helix models dull. I'll try to use both returns with every sim in mono (5 cable method??). Althought i read that a splitter cable from the helix return into both returns would be the right way, i don't know..

[rd2rk]

According to the manual, using the Left Return is MONO, and you'll be using BOTH amps. No need for extra cables. If wiring from Helix L/Mono to Valvestate Left Return doesn't work, there's something else going on.

[NecrosisFactorG]

1 hour ago, rd2rk said:

According to the manual, using the Left Return is MONO, and you'll be using BOTH amps. No need for extra cables. If wiring from Helix L/Mono to Valvestate Left Return doesn't work, there's something else going on.

Maybe i have to make a specific setup to  the send/return blocks so there's no valvestate preamp dry singal going to the power amp? with the 4CM

[rd2rk]

4cm:

 

Guitar>Helix Input>Helix effect>Helix FX Loop Block>Helix Send>Amp Input> Amp FX Send>Helix Return>Helix effect>Helix L/MONO Out>Amp LEFT FX Return.

Amp FX Mix full Clockwise. That should send the full preamp signal through the Loop. You should NOT have to use both Returns UNLESS you're using stereo effects in Helix.