Unwanted phase sound on effects loop: Roadster Ch. 4 Modern

[Fulltone74]

Hi all:

Wondering if any of you have seen this issue:

When I run the effects loop on Ch. 4 Modern mode on my Roadster, I get an unwanted "phase" or "flange" type of sound.
This does not happen in the other two gain modes of Ch. 4, nor in any other channel in any gain mode.
Changing the send level does not help the issue.

Is this something normal on this amp? This is my first Mesa amp, so I'm not sure if this is normal or not.
Actually, i would prefer if this wasn't happening, as this issue makes this channel and mode otherwise unusable for me because of this problem.

I was thinking maybe a bad effects loop tube, but all the other channels and modes work correctly... ???

 

[bendo]

No, that is not normal. I would start with replacing the tubes for the FX loop and Ch3/4 with KNOWN good tubes.

V5 -FX
V2-3 Ch4.

If that does not resolve the issue, take it to a tech, could be a bad capacitor or resistor somewhere. Is it still under warranty? If so, contact Mesa.

Is there anything plugged into the loop?

 

[Fulltone74]

Hello Bendo:

Thanks. I will try replacing the tubes.
One thing I did notice is that if I have the main master and/or solo knobs turned up a little bit from bare minimum bedroom volume levels, that phase sound largely goes away. Almost like there is just a little bit of constant fixed low-level bleed of the dry signal somewhere to the main master that becomes apparent at very low volumes. I still only notice that effect on channel 4 Modern.

So leads me to believe whatever is going on won't be noticeable at band practice or gigs. At least hopefully not.

 

[domct203]

What you are hearing is the cross-bleed between the triodes of your FX Driver tube. This is something you can hear at very low volumes, especially in Modern mode of the red channel. It should go completely away at the volumes the amp was designed to be run at (stage volumes).

The reason it is so apparent in Modern mode is due to the power amp's increased input sensitivity in that mode.

Get that puppy up to volume and the phase sound you hear should go completely away.

Dom

 

[joe web]

What you are hearing is the cross-bleed between the triodes of your FX Driver tube. This is something you can hear at very low volumes, especially in Modern mode of the red channel. It should go completely away at the volumes the amp was designed to be run at (stage volumes).

The reason it is so apparent in Modern mode is due to the power amp's increased input sensitivity in that mode.

Get that puppy up to volume and the phase sound you hear should go completely away.

Dom

that´s it! like dom said.

i´ve read so often questions like yours in the first posting and every time the problem is, these amps are played at low-level....you get that phase-shift even with a marshall amp played at bedroom level....and with many other amps as well.

take this beast and bring it to your rehearsal room to rock the sh!t out of it, because this amps were not designed to be played at bedrooms!
the roadster is by far one of the best amps out there on the market. i´m using mine since 7 years now, tried a lot of different amps during this time, but no other amps delivered me THAT sound and flexibility like the roadster. always have an eye on a VH4 but only as an addition, will not sell the roadster for any other amp.