Einstein - does it have a hum trim pot?

[Dallas Marlow]

Haha, I think it was just a dirty pot I ran it around a time or two to try and clean it out and no problems I was trying to figure out how to get contact cleaner into that little ass pot but I can't figure out how, so hopefully it'll be good!

I already cranked it earlier! Just got back from work and will be back on it soon!

 

[eddyrox]

The hum trimmer affects the whole amp (the heater to ground actually) - so your problem is caused by faulty preamp tubes.

so olaf, is your advice NOT to adjust this even if there is humming on all channels (after swapping out all tubes)?

 

[Dallas Marlow]

I don't think that's the case, there was a VERY unusual fluke which was the result of a dirty hum trimmer pot, or a lose hum trimmer pot. It is possible it got shaken loose in the process of being moved, or just got some kind of dust in it some how I do not know... Also, for whatever reason the hum was showing up on certain channels significantly more than others - I don't know the reason for this either. It wasn't until closer observation and messing with gain controls that I was able to replicate the hum on all channels, it was just buried in the back ground more and hidden so I thought it was only on two of the four modes.

I think his original diagnosis would be correct 99% of the time, usually on any multi channel amp where you have noise on some channels and not others it can be traced back to the pre-amp tubes. His conclusion was only hindered by my faulty information.

I believe what he was trying to convey is that for noise on all channels the hum pot COULD need adjustment, that does NOT mean that it is the cause/source of the hum because it very well could be tubes. However; if there is hum on only SOME of the channels the fault most likely lies with in the pre-amp tubes.

Hope this helps and someone please correct me if I am mistaken.

Dallas

 

[eddyrox]

I don't think that's the case, there was a VERY unusual fluke which was the result of a dirty hum trimmer pot, or a lose hum trimmer pot. It is possible it got shaken loose in the process of being moved, or just got some kind of dust in it some how I do not know... Also, for whatever reason the hum was showing up on certain channels significantly more than others - I don't know the reason for this either. It wasn't until closer observation and messing with gain controls that I was able to replicate the hum on all channels, it was just buried in the back ground more and hidden so I thought it was only on two of the four modes.

I think his original diagnosis would be correct 99% of the time, usually on any multi channel amp where you have noise on some channels and not others it can be traced back to the pre-amp tubes. His conclusion was only hindered by my faulty information.

I believe what he was trying to convey is that for noise on all channels the hum pot COULD need adjustment, that does NOT mean that it is the cause/source of the hum because it very well could be tubes. However; if there is hum on only SOME of the channels the fault most likely lies with in the pre-amp tubes.

Hope this helps and someone please correct me if I am mistaken.

Dallas

Dallas, thank you for the clarification, because I'm experiencing higher humming than normal (compared to my Herbert or VH4). I suspect that the hum trim pot needs adjusting, but wanted to clarify what it would do to the amp before proceeding. If adjusting the hum trim pot only eliminates the excess humming from the hi-gain head, then no problem. BUT if it impacts other functions (which I suspect it does) I just wanted to be aware prior to twisting and turning anything.
Regards,
mike

 

[Dallas Marlow]

I don't think that's the case, there was a VERY unusual fluke which was the result of a dirty hum trimmer pot, or a lose hum trimmer pot. It is possible it got shaken loose in the process of being moved, or just got some kind of dust in it some how I do not know... Also, for whatever reason the hum was showing up on certain channels significantly more than others - I don't know the reason for this either. It wasn't until closer observation and messing with gain controls that I was able to replicate the hum on all channels, it was just buried in the back ground more and hidden so I thought it was only on two of the four modes.

I think his original diagnosis would be correct 99% of the time, usually on any multi channel amp where you have noise on some channels and not others it can be traced back to the pre-amp tubes. His conclusion was only hindered by my faulty information.

I believe what he was trying to convey is that for noise on all channels the hum pot COULD need adjustment, that does NOT mean that it is the cause/source of the hum because it very well could be tubes. However; if there is hum on only SOME of the channels the fault most likely lies with in the pre-amp tubes.

Hope this helps and someone please correct me if I am mistaken.

Dallas

Dallas, thank you for the clarification, because I'm experiencing higher humming than normal (compared to my Herbert or VH4). I suspect that the hum trim pot needs adjusting, but wanted to clarify what it would do to the amp before proceeding. If adjusting the hum trim pot only eliminates the excess humming from the hi-gain head, then no problem. BUT if it impacts other functions (which I suspect it does) I just wanted to be aware prior to twisting and turning anything.
Regards,
mike

Hey Mike,

Your very welcome and glad I could help you out! I believe Peter stated some where that the Hum trim pot should be adjusted to the lowest noise on the highest gain channel, I think I actually read it about the VH4 and he said channel 4 so I assume that translates to CH2 on the Einstein. Also don't forget when your adjusting, as simple as this sounds, you will need to have a cable plugged into the amp otherwise no sound at all will come out of it haha. I just turned my guitars volume totally off and plugged it into the amp to listen for it.

Dallas

 

[eddyrox]

excellent. thank you Dallas for clarifying!
best,
mike.

 

[Dallas Marlow]

Your more than welcome man, any time!

Dallas