jhczar
10-24-2006, 07:30 AM
I've never done any tweaking of amps, so this is a bit new to me.
To manage my volume, I ran out & bought a 12AT7 to put in one of the preamp slots in my HRD. I tried it in slot 1, and was able to run with the volume all the way with a really nice growl. It was surprisingly quiet, almost not loud enough for a large room. I'm not using the drive channel here, just clean turned up with a lower gain preamp tube.
In the 3rd slot, it made a significant difference, louder and fuller growl, but has really nasty breakup on the high end. I only hear the nastiness when I'm hitting the strings hard. Same thing here, no OD channel, just clean turned all the way up. Interestingly, if I turn on the OD channel with this setting, the nastiness goes away, but so does some of my low end.
When I bought the tube I was in a hurry, and GC only had a Mesa tube, rather than any of the other brands I've heard of. Did I just buy a crappy tube, or is the nasty breakup due to something else like slot location?
A few other questions...
1. I'm considering replacing the speaker in this amp too. It's a 40 watt amp. I'm considering a Hellatone 60. Is this appropriately sized?
2. To drain the filter caps using a resistor across the leads, what size resister would I need? I've spent a long time looking at Justin Holton's page and just don't see a rating for the resistor he recommends in his draining method.
Any help would be appreciated.
To manage my volume, I ran out & bought a 12AT7 to put in one of the preamp slots in my HRD. I tried it in slot 1, and was able to run with the volume all the way with a really nice growl. It was surprisingly quiet, almost not loud enough for a large room. I'm not using the drive channel here, just clean turned up with a lower gain preamp tube.
In the 3rd slot, it made a significant difference, louder and fuller growl, but has really nasty breakup on the high end. I only hear the nastiness when I'm hitting the strings hard. Same thing here, no OD channel, just clean turned all the way up. Interestingly, if I turn on the OD channel with this setting, the nastiness goes away, but so does some of my low end.
When I bought the tube I was in a hurry, and GC only had a Mesa tube, rather than any of the other brands I've heard of. Did I just buy a crappy tube, or is the nasty breakup due to something else like slot location?
A few other questions...
1. I'm considering replacing the speaker in this amp too. It's a 40 watt amp. I'm considering a Hellatone 60. Is this appropriately sized?
2. To drain the filter caps using a resistor across the leads, what size resister would I need? I've spent a long time looking at Justin Holton's page and just don't see a rating for the resistor he recommends in his draining method.
Any help would be appreciated.