robberns
Well-known member
Just got around to doing some tube-swapping in my Mini, made some interesting observations.
I'm just one of those guys who will swap out new production tubes for NOS just because. I like old glass.
So first was replacing the EL84's with NOS GE EL84's.
Then, I really wanted to get the best clean tone from Channel 1, while taming Channel 2 a bit. I am a classic rock guy (geezer) and the Mini had way more gain on Channel 2 than I would ever use.
So I got out my collection of pre-amp tubes and the list of gain factors for various tubes. For those of you who aren't familiar with this, there are a number of tubes you can run where 12AX7's are used. Some have less gain and can be used to clean up or tighten amps that drive the tubes harder. Also keep in mind that 12AX7 tubes are actually 2-tubes in one. So in the Mini Rec,. if you check the tube chart, you'll see that each pre-amp tube serves multiple purposes.
I put a NOS JAN GE 5751 in V1 with the intention of keeping my clean tone as clean as possible. V1 handles the input stage for Ch1 and Ch2, as well as the 3rd gain stage for Ch1. Sounds great. Wasn't horrible before, but is better now.
Then I worked on the Channel 2 gain issue. I would never run the Gain over 10:00, just got too messy for me.
So I put a 5751 in V2 (2nd gain stage Ch1 and Ch2, and 3rd gain stage Ch2). Didn't really make a big difference.
So I moved down the list to a lower gain tube than the 5751, a 12AT7. I had a nice NOS Mullard in my stash. Bingo! Lowered the gain on Ch2 so now I get more of a classic "Marshally" crunch when running the gain control at around 11:00.
The moral of the story (if there needs to be a moral) is play around with tubes and have fun.
I'm just one of those guys who will swap out new production tubes for NOS just because. I like old glass.
So first was replacing the EL84's with NOS GE EL84's.
Then, I really wanted to get the best clean tone from Channel 1, while taming Channel 2 a bit. I am a classic rock guy (geezer) and the Mini had way more gain on Channel 2 than I would ever use.
So I got out my collection of pre-amp tubes and the list of gain factors for various tubes. For those of you who aren't familiar with this, there are a number of tubes you can run where 12AX7's are used. Some have less gain and can be used to clean up or tighten amps that drive the tubes harder. Also keep in mind that 12AX7 tubes are actually 2-tubes in one. So in the Mini Rec,. if you check the tube chart, you'll see that each pre-amp tube serves multiple purposes.
I put a NOS JAN GE 5751 in V1 with the intention of keeping my clean tone as clean as possible. V1 handles the input stage for Ch1 and Ch2, as well as the 3rd gain stage for Ch1. Sounds great. Wasn't horrible before, but is better now.
Then I worked on the Channel 2 gain issue. I would never run the Gain over 10:00, just got too messy for me.
So I put a 5751 in V2 (2nd gain stage Ch1 and Ch2, and 3rd gain stage Ch2). Didn't really make a big difference.
So I moved down the list to a lower gain tube than the 5751, a 12AT7. I had a nice NOS Mullard in my stash. Bingo! Lowered the gain on Ch2 so now I get more of a classic "Marshally" crunch when running the gain control at around 11:00.
The moral of the story (if there needs to be a moral) is play around with tubes and have fun.