::Issue Resolved:: Thanks boogie customer service. Mark V Ch

Adamsh187 · Nov 13, 2015

Hey Boogie Board,

I have an issue with a brand new Mark V head that I recently bought. There is a bad hum present on Channel 1, but only when the reverb is engaged. Anyone else had this issue before?

Also I noticed when I lift my amp and place it down there is jangling sound like something is loose in there. Is this normal? Is that just the springs from the reverb or could it be something else like a broken tube or something? Could this have something to do with the hum when the reverb is on?

Otherwise the amp is awesome. I'm still within the 30 return period of this amp and I want to make sure I didn't get a dud.

Thanks!

-Adam

Monstercastle · Nov 13, 2015

Is the reverb related hum only on channel 1, but not on other channels? It could be a tube issue and perhaps a pre-amp tube that is specific to channel 1 gain modes might be noisy, and the reverb effect is making that stand out more. If reverb is noisy on the other channels as well, you could look at V4 & V5 which are the two tubes in reverb send/return.

Adamsh187 · Nov 13, 2015

The hum is only on Channel 1 when the reverb is engaged. Everything else seems to be fine. Do you think maybe a preamp tube broke in the shipping process?

Monstercastle · Nov 13, 2015

Try replacing V3 with a different 12ax7 and see if the problem changes. V1 is the only other tube that's involved with Channel 1, but a problem there would most likely show up with noise on the other channels too, since V1 is a gain stage in all channels. If you don't have a spare preamp tube, try swapping V3 with say V6, and see if the noise quiets down. If it does you know you need to replace V3 with a new tube.

Tube functions are spelled out in the user manual towards the back.

Adamsh187 · Nov 13, 2015

I'll give that a try and report back. Thanks for the help and for pointing me in the right direction. Any insight into the rattling sound I'm getting when the amp is moved?

Monstercastle · Nov 15, 2015

The rattling could just be the reverb tank. If simply tilting the head causes the rattle, it's possible one of the springs came off in the tank. Spring tanks can rattle a bit when the head takes a slight impact.

Monstercastle · Nov 20, 2015

@Adamsh187 - Any luck?

Adamsh187 · Jan 15, 2016

I actually did have luck. I called the guys at boogie and they informed that a mild amount of hum was supposed to be present on the first channel with the reverb on because its so close to the transformer. I've come to realize I over reacted and was just nervous. The boogie sounds amazing and I'm happy to report things couldn't be better. Thanks of the help.