Post by drsam on May 9, 2021 8:41:35 GMT -7
So, I'm really scratching my head over this. I'm not a full fledged amp tech, but I'm not a novice either and I thought I knew enough to diagnose most minor issues with a relatively good degree of confidence.
I have a Maz 18 Mk2 Reverb combo with the G12H30 70th Anniversary, and the exact Z recommended tube compliment including the NOS 6n14n power tubes.
My amp was very sparkly, and I always used the cut set from about noon-2:00 or it was just way too sparkly for me. Now, almost overnight, it has lost its sparkle even with the cut wide open.
It also seems to have less gain than it did. Either that or is gain with a more compressed sound- minus much of the "bite" and "sparkly crunchiness" it had.
Now, there are a few things that I have always considered general rules of thumb in minor diagnosis of my own amps. First is to check the easiest to address problems first.
So tubes?
Another thought would be the speaker breaking in, except that I would expect that to be fairly gradual. The speaker, however, was well broken in long before the current issue arose and this was not a long gradual change.
I tried disconnecting the footswitch too, just for good measure, even though I doubted that would change anything. It didn't.
I also considered outside the amp:
Its also in the same place in the same room as it was before, when it had all of its glorious sparkle. So, its not a change in environment causing it.
I'm not trying to sound like a "know it all" with all of the above. I just wanted to let you know what I've already tried or thought I had reason to rule out... to save some time for all. If you think any of my assumptions are in error, please do explain. I'm always up for learning something I wasn't aware of previously. I just base my assumptions on past experience with playing tube amps for 30-40 yrs and having to figure some things out along the way. I know there are plenty out there with more diagnostic expertise and I appreciate any good advice you can offer.
So, what now? Its probably a fairly minor change for most people, but I'm OCD about these things and the average person who played it right now would probably would assume everything to be normal if they hadn't been playing THIS amp for a few days before it changed.
I'm sure someone will ask, "if its such a minor change like that, why does it matter?", so I'll answer that right off... Well, that bit of top end bite & sparkle that is gone also happens to be the thing that made me love the amp. I want it back.
So who has a suggestion that I haven't tried yet, something I haven't considered, or something else I didn't realize?
Thanks...
Sam
I have a Maz 18 Mk2 Reverb combo with the G12H30 70th Anniversary, and the exact Z recommended tube compliment including the NOS 6n14n power tubes.
My amp was very sparkly, and I always used the cut set from about noon-2:00 or it was just way too sparkly for me. Now, almost overnight, it has lost its sparkle even with the cut wide open.
It also seems to have less gain than it did. Either that or is gain with a more compressed sound- minus much of the "bite" and "sparkly crunchiness" it had.
Now, there are a few things that I have always considered general rules of thumb in minor diagnosis of my own amps. First is to check the easiest to address problems first.
So tubes?
- If it were a preamp tube, I would expect any of a few types of noisiness. No noise.
- If it were power tubes, I would expect it to come on gradually unless it were a major fault, which would be obvious and not simply alter the tone. This came on suddenly, but is not a major fault with no red plating or horrendous crashing noise.
- If it were a rectifier, I wouldn't expect a loss of top end, so much as a short/blown fuse. No short. No blown fuses.
Another thought would be the speaker breaking in, except that I would expect that to be fairly gradual. The speaker, however, was well broken in long before the current issue arose and this was not a long gradual change.
I tried disconnecting the footswitch too, just for good measure, even though I doubted that would change anything. It didn't.
I also considered outside the amp:
- New or bad cables? Checked all cables and substituted other known good, low C cables- didn't help.
- New effects pedals? Completely removed all effects and went straight into amp- didn't help.
Its also in the same place in the same room as it was before, when it had all of its glorious sparkle. So, its not a change in environment causing it.
I'm not trying to sound like a "know it all" with all of the above. I just wanted to let you know what I've already tried or thought I had reason to rule out... to save some time for all. If you think any of my assumptions are in error, please do explain. I'm always up for learning something I wasn't aware of previously. I just base my assumptions on past experience with playing tube amps for 30-40 yrs and having to figure some things out along the way. I know there are plenty out there with more diagnostic expertise and I appreciate any good advice you can offer.
So, what now? Its probably a fairly minor change for most people, but I'm OCD about these things and the average person who played it right now would probably would assume everything to be normal if they hadn't been playing THIS amp for a few days before it changed.
I'm sure someone will ask, "if its such a minor change like that, why does it matter?", so I'll answer that right off... Well, that bit of top end bite & sparkle that is gone also happens to be the thing that made me love the amp. I want it back.
So who has a suggestion that I haven't tried yet, something I haven't considered, or something else I didn't realize?
Thanks...
Sam