FourT6and2 wrote: ↑Wed Dec 12, 2018 4:08 pm
I know you fixed the issue (what was it?). But from the looks of it, you've got a bunch of ground loops. For example you've got a nice bus wire between the pots and board to which you've grounded some things. But then you've got one of the pots grounded right to the chassis instead of the ground bus? And the ground bus is grounded to the chassis in two different places. You really should only have one connection to chassis ground, not like 5 on the same ground plane. I know you say the amp sounds good, but I'm willing to bet if you address your grounding issues, it will sound even better and lower the noise floor.
The issue was a loose connection wire on the under side of the board. I replaced it with a new wire topside. Thanks for the suggestions on the grounding. I started grounding one way then came across another method on the Metro forum called the "Larry Grounding" method. I kind of mixed and matched, but to be honest, this has one of the lowest noise floors of any amp I've ever played. Way quieter than my Liverpool build.
If it ain't broke....<shrug>
Reeltarded wrote: ↑Wed Dec 12, 2018 12:25 pm
Looks like a proper amp! Love the logo too!
Bad!! Bad!! Ditch the tube rectifier! It's a primary failure point and silicon is almost unkillable if you triple up... and they cost almost 20 cents for the 6.
Good point and thanks. 6:25am? I didn't think guitar players could function that early!
Reeltarded wrote: ↑Wed Dec 12, 2018 12:25 pm
Looks like a proper amp! Love the logo too!
Bad!! Bad!! Ditch the tube rectifier! It's a primary failure point and silicon is almost unkillable if you triple up... and they cost almost 20 cents for the 6.
Good point and thanks. 6:25am? I didn't think guitar players could function that early!
They can't get you if you never go to sleep!
Do the Larry grounding completely when you get a chance. Your highest notes will be sweeter. Never phase beat even with lowish filtering.
Signatures have a 255 character limit that I could abuse, but I am not Cecil B. DeMille.
The 6550 will bias with more negative voltage on the grid, so some modification to the bias circuit will be required. Assuming the schematic below is the right one, then changing R28 from 22K to something larger like 47K will probably give you enough range on the bias pot to work with 6550.
Supposedly, the 6550 is more sensitive to resistance in the grid circuit. In some case you might need to reduce the grid leak resistors (R26, R27) if they're too big (like 220K or bigger) but 150K will probably be alright. Or, change them to 100K if you feel like it.
and thanks. 6:25am? I didn't think guitar players could function that early!
