Wet dry wet question

[rokker]

I finally got the wet dry wet setup wired up.
Have a cameron atomica and fender drri hooked up to a rjm rack gizmo and mixer.
From there have a GM2/matrix1000/2 mesa cabs

When i turnup the wet channels i get a feedback loop. Do not think it is a ground loop but it just roars particlarly when i use the modulation fx on the gm2.
Any ideas what is causing it and what i need to do differently?

 

[Anonymous]

I finally got the wet dry wet setup wired up.
Have a cameron atomica and fender drri hooked up to a rjm rack gizmo and mixer.
From there have a GM2/matrix1000/2 mesa cabs

When i turnup the wet channels i get a feedback loop. Do not think it is a ground loop but it just roars particlarly when i use the modulation fx on the gm2.
Any ideas what is causing it and what i need to do differently?

For W/D/W, you have to have three cabs, one of which would be completely dry directly from the amp. Since you only have 2 cabs, is one of the cabs stereo? If not, I don't see how you are doing W/D/W.

I get the problem you describe sometimes in my 3 4x12 W/D/W setup if the wet is too high in a small room (only with modulation effects do I get this). Turning down the wet signal fixes it. Also, mixing in some dry signal in the wet cabs eliminates the problem for good at any volume of those cabs. While this is really W-D/D/W-D, that is how most of the pros do it anyway. How big is the room you're playing in and how loud are you playing?

It would also be helpful to know the exact signal path. Your description is a bit vague. Lot of equipment in that setup to troubleshoot without a patch to patch description...

Steve

 

[eljodon]

A better description of your gear would be helpful.I use a Attenuator that has a line out and I use a DI box that has a ground lift and phase switch and I plug into my mixing board using the XLR(phantom power) and it get's rid of the feedback. I also try to lower the output coming out of Attenuator(in your case the amp out) and make up the gain by increasing the pad on your mixer.I use a Radial DI box which to my ears is quite transparent, but any DI will do as long as it has a ground lift and phase switch. But knowing your set up would really help. Hope this helps!

 

[rokker]

Sorry guys for the vagueness
Heres a complete rundown
Cameron into a marshall 4x12 itha line out box feeding the rjm mini mixer
Frnder drri combo with line out also feeding the mixer
Output from the mixer going into the gm2 and then through the matrix into to wet cabs (mesa 1x12's)
Also have a rjm rack gizmo for swithcing and a voodoo gcp to run it

The room is small...15x20 and i am not playing much above90-95 db

I lowered the gm2 to pro level and that seemed to help but it seems to be very sensitive to the modulation.

 

[petejt]

For W/D/W, you have to have three cabs, one of which would be completely dry directly from the amp.

You don't need three speaker cabinets for wet/dry/wet.

You just need three separate speaker signals- one of them DRY (unprocessed, coming straight from the amp), and the other two WET (ie Processed with effects).

The dry signal generally goes between the wet signals, to preserve the core tone, otherwise the processed 'wet' sound can get a bit washy and weak no matter how loud it is amplified. That is the nature of heavily effected signals.

You can use two stereo cabs, which in effect provide you with FOUR separate speaker signal paths. That way if you want, you can have wet/dry/wet/dry, dry/wet/dry/wet, dry/wet/wet/dry, wet/dry/dry/wet, dry/wet/wet/dry, dry/dry/wet/wet, wet/wet/dry/dry, whatever combo you want.

Also, mixing in some dry signal in the wet cabs eliminates the problem for good at any volume of those cabs.

If you electrically "mix" the signals, then you no longer have a dry signal! A dry+wet signal = wet signal!
It just dilutes the amount of effected signal in the mix.

 

[Anonymous]

For W/D/W, you have to have three cabs, one of which would be completely dry directly from the amp.

You don't need three speaker cabinets for wet/dry/wet.

You just need three separate speaker signals- one of them DRY (unprocessed, coming straight from the amp), and the other two WET (ie Processed with effects).

The dry signal generally goes between the wet signals, to preserve the core tone, otherwise the processed 'wet' sound can get a bit washy and weak no matter how loud it is amplified. That is the nature of heavily effected signals.

You can use two stereo cabs, which in effect provide you with FOUR separate speaker signal paths. That way if you want, you can have wet/dry/wet/dry, dry/wet/dry/wet, dry/wet/wet/dry, wet/dry/dry/wet, dry/wet/wet/dry, dry/dry/wet/wet, wet/wet/dry/dry, whatever combo you want.

Also, mixing in some dry signal in the wet cabs eliminates the problem for good at any volume of those cabs.

If you electrically "mix" the signals, then you no longer have a dry signal! A dry+wet signal = wet signal!
It just dilutes the amount of effected signal in the mix.

On the three cab thing, I immediately said he could have one cab be stereo and approximate W/D/W in a 2 cab setup, so no need to correct me, I already corrected myself. Obviously, I know that you need three separate speaker signals, but once again, thank you for the explanation.

As far as my suggestion to mix some dry in with the wet left and right signals, my rig, and many pro rigs sound great that way. You can, of course, choose to setup your rig any way you'd like.

Steve

 

[petejt]

On the three cab thing, I immediately said he could have one cab be stereo and approximate W/D/W in a 2 cab setup, so no need to correct me, I already corrected myself. Obviously, I know that you need three separate speaker signals, but once again, thank you for the explanation.

No worries. Sorry for me doubling up there.

As far as my suggestion to mix some dry in with the wet left and right signals, my rig, and many pro rigs sound great that way. You can, of course, choose to setup your rig any way you'd like.

I have heard of other folks doing that- but yeah to me it just defeats the purpose of having separate wet & dry signals in the first place?


When you "mix some dry in with the wet left and right signals"- are you saying that you run the wet signals and the dry signal into an electronic Mixer (such as a Rane splitter/mixer), and combine particular ratios of each signal together (say 10% dry + 90% wet) for the FINAL left and right "wet" output signals? And then run the fully dry DRY signal in the speaker/cab that is between the left and right 'wet' speakers?