I've heard conflicting things around the best practice for using the wattage output switch on tube/valve head units (such as those found on amps like the Marshall Origin 50). That is, switching between 0.5, 10, or 50 watt, for example...
I've been told that I should absolutely turn the amp off, let it sit for a minute or so, before selecting the desired output, then turning it back on again.
But equally I've been told that it doesn't matter, and you can switch away while the amp is in full flight.
What's the consensus?
Wattage switch on tube amp heads.
Moderators: pompeiisneaks, Colossal
Re: Wattage switch on tube amp heads.
Show us a schematic, and we can comment. It's unlikely to be harmful to the tubes to hot switch.
I build and repair tube amps. http://amps.monkeymatic.com
-
Stevem
- Posts: 5144
- Joined: Fri Jan 24, 2014 3:01 pm
- Location: 1/3rd the way out one of the arms of the Milkyway.
Re: Wattage switch on tube amp heads.
When switching as long as no signal is passing thru the amp no harm will to any part of the amp.
When I die, I want to go like my Grandfather did, peacefully in his sleep.
Not screaming like the passengers in his car!
Cutting out a man's tongue does not mean he’s a liar, but it does show that you fear the truth he might speak about you!
Not screaming like the passengers in his car!
Cutting out a man's tongue does not mean he’s a liar, but it does show that you fear the truth he might speak about you!
Re: Wattage switch on tube amp heads.
I haven’t seen an official Marshall schematic for the origin series, but I do know the Studio series’ 20/5W switch works by lowering B+ to the output section. It shouldn’t hurt the amp switching rapidly, but switching it often will be hard on the switch since it directs DC. Seems to me that it would have made more sense for them to use a 3 position 3pdt mains switch to control wattage.