losing volume, help!

[sruby6]

I have had this happen to me twice now; I lose volume for awhile then it comes back. Both times have been with different cab set ups and different cables. Also, I have a practice amp at home that it does not happen on so I am thinking it is not the bass. When I lose volume I am still getting a signal through my head. If anybody has any suggestions it will be much appreciated! Thanks in advance.
Sean

[craig.p]

Admittedly a total swag here, but I'd suspect your amp's speaker jack. I say this only because I have an MB200 with one of those combination Speakon+phone jacks, and the phone jack portion of it does just what your amp's doing. Not saying this IS the cause in your case, just something to check. You may (and I know I incur Paul's ire by even suggesting this) want to open the amp up and have a look at the connection between the amp's power output stage and the speaker jack. Could be a bum solder connection, or a cheap-ass phone jack, or who knows what else.

Anyway... that's where I'd start.

[Art Araya]

i've had problems like this before with different causes. check your entire signal chain... is your bass an active bass? check the battery.
check the cables
check the head
check the cab
check the cable from the head to the cab
are you using effects pedals? check their batteries and cables...

[BrianVengeance]

If you have a tube head, it may be time to replace the tubes.

[sruby6]

First time I was using 1/4" cables and the second time I was using a speakon. I just replaced the tube in the head. As for the effects I used my full board the first time and second time I only used the compressor and tuner. I unplugged and went directly into the head and still had volume issue. The head is a SWR750.

[BassmanPaul]

If the brute has an effects loop try jumpering the send and return with a signal cable and see if that helps.