SwampDonkey":1b9ch53v said:
So today I got my Herbert that I traded for my ENGL SE. I plug in the cabs, and my Les Paul and straight away I have issues.
The channel volumes on channels 2 and 3 are not doing what they are supposed to. When I have the channel volume midway (12:00) the sound is thin, when I turn it to the left it gets thicker and louder and when I turn it to the right (from 12:00) it gets louder but more trebly. Also while playing I get volume swells and drops and strange sounds.
Any ideas?
First off, I would never buy a used amp without checking the bias and having a look at the tubes. Then I would probably change them out fairly quickly, just for shits and giggles - unless it came from someone I knew who took care of it and these things.
The first part of your question is just getting familiar with the amp and what it will do. If you give a hint of what you like to play, some of us may be able to give you some settings across the channels. I don't use channel 1, so no help there. But, two and three I can.
Use the mid-cut as to me, this makes the Herbie what it is (personal opinion before anyone jumps on me). Without it, I wouldn't have any need for the amp. It is always on.
Using V2 will also give you some more EQ control at the power amp stage, which is huge, especially when you get some respectable volumes going.
When you adjust the channel volumes, the tone will vary, depending on where you are on your master. To start you off, kick the gains up to 1:00 and the volumes up around the same on each channel. Use the master at a lower level to help saturate the power end.
I usually run my channel mids all the way off and the treble up fairly high. I am scooped.....
For your volume swell problem, that certainly isn't right. You could spend some time on each channel to see if the swell is there across all channels and narrow it down to a particular pre-amp tube or two. Or, it could be the phase inverter tube (the last pre amp tube). Or, just bight the bullet and replace them all. In a pinch, most any 12AX7 will do. When you are ready to experiment with tone, there are lots of different choices. If the problem was across all channels, then V1 preamp tube may be the culprit. With 6 power tubes, I doubt one bad one would affect the amp in volume or tone unless you were really used to the amp. Although, you may get some other unpleasant noise along with it. But, you should pull the grill off with the amp on and make sure all the power tubes are glowing as they should, and none with any really red glow on the glass or any that look weak. You can replace Herbies tubes in matched sets. Maybe you should grab a matched set of 34's just to replace and experiment with before laying out a few bills on a sextet of 88's.
99% of the problems can be corrected here with the tubes. Not to say that it couldn't be something else. But, I doubt it.
The Herbert is a very easy amp to dial in and sound good once you know your way around it a bit. You can find lots of help and opinions here. Any problems, just ask!
Steve
