Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: joesatch on January 27, 2022, 03:22:30 pm

Title: 100 iron in 50 watt build?
Post by: joesatch on January 27, 2022, 03:22:30 pm
Question, i have a 100 watt transformer set for marshall but wanted to build a 2204 with it (50 watts). Would i build this normally and just put the OT 4ohm tap to the 8ohm speaker jack and 8ohm OT tap to the 16ohm speaker jack? Would i need to change anything else in the circuit (aside from possibly upping the dropping resistors)
Title: Re: 100 iron in 50 watt build?
Post by: sluckey on January 27, 2022, 03:35:07 pm
Should work. You will need to connect the PT according to the 2203 schematic.
Title: Re: 100 iron in 50 watt build?
Post by: uki on January 27, 2022, 04:21:32 pm
I would not use a 100w OT for a 50w amp, its not about if will work or not, but because the OT could be used for a 100w amp. You could build a 100w amp with that OT !  I would !!  I think, matching parts as best as possible gives better results. Not trying to change your mind but think about it, maybe it could be a good challenge !
Title: Re: 100 iron in 50 watt build?
Post by: thetragichero on January 27, 2022, 07:37:24 pm
keep in mind that a 50w amp will not load the 100w power transformer nearly as much so you will likely have a much cleaner amp
really it'll be a completely different amp since your power supply voltages will all be higher
Title: Re: 100 iron in 50 watt build?
Post by: Bieworm on January 28, 2022, 04:58:26 am
I'd do the 100W too...
They are louder, but not twice the volume.. rather like 10% area.

If you get to crank a 50W then you could also crank  a 100W. At that volume you'd hardly hear the difference.
PLUS then it will sound 100% marshall,  for they were initially designed as 100W amps😄👍
Title: Re: 100 iron in 50 watt build?
Post by: shooter on January 28, 2022, 09:18:16 am
I'll be the dissenter and say a 100W OT in a 50W build is just fine.
I used a set of iron meant for a Marshall 100 in a 30-ish watt PP self biased amp
my OT had UL taps and used them - EL34's for the PA,  plexi-ish pre.
It's the only amp I've designed that got unanimous thumbs up from the test guitarists, and they're a tough crowd!
the ONLY complaint  "you can't screw up, you will ear every missed note and it will sing out like a slapped face"  :icon_biggrin: