Video clip, MOD 102 5w Amp Kit

[Belva]

There are also 5W amps that have a pentode/triode switch. Can't think of any off hand. VHT special 6 maybe? I do know the Special 6 is built to be modded. I also saw a pentode/triode kit IIRC at Weber. I do know Weber sells a kit that will allow quick and easy power tube swaps with minimal tweaking. So going from, say, a 6V6 to a 6L6 is an option. My ultimate amp would be a 5E3 circuit with pentode/triode and multiple power tube capability. Basically a one size fits all amp. Something that would go from a few watts all the way up to 40.

[Zozobra]

For that I'd implement power scaling. A simple VVR circuit is really easy to put in a 20W cathode biased amp and all it needs is a MOSFET and a pot. Much above 350V on the plates requires a few more parts but its still fairly simple. Fixed bias complicates things as its necessary to add a bias tracking circuit.

[Casey4s]

 

Very nice. I dont think 5W is too much for the home. It might be late at night but you can get away with a few hours a week at that sort of volume easily enough!

 

 

JJ Electronics make a new EL84 replacement called the EL844 it has less output power but is said to have better harmonics and a smoother overdrive. I just got one but haven't tried it yet. If it works as advrtised it may help several kinds of amps lower power output, for apartments and dorms.

[Zozobra]

I dont have much experience with EL84s to be honest. I've been sticking with 6V6's for my low output amps as they're more suited to the power transformers I can get a hold of readily. If you're interested in the power scaling circuit the link in my sig to my amp build has the schematic in. Its pretty simple. I've chosen to apply it to only the plates and screens but there is no reason why you cant include the PI and even the whole preamp if you want to go for the brown sound.