I'm one of the odd ones who actually prefers
6L6 types in the VH4.
Of course EL34s give you a more classic Marshall crunch ... but that's not what I'm after usually.
You can use a 5881 as long as it can handle the plate voltage (460-470v)
Just put the switch in the 6L6 position.
Actually spent a few hours today rolling different tubes I hadn't tried before in the VH4,
Here's a run down of my thoughts on the 6L6's.
Sovtek 6L6 wxt+ - great tube, musical, don't let the low price scare you.
Nice cleans.
Slightly compressed crunch. A little compact sounding when pushed.
( some will like this)
Tung Sol 7581A - I had high hopes for this tube. Was disappointed.
Almost solid state like response, no give , very clear and linear.
No character. Hifi guys after detail must love this tube.
The Tung Sol 6L6 GC-STR.
very musical tube , nice crunch, quite open sounding
Clear but not hard or harsh.
They're in the amp now, I think my new favourite.
My standby for 10 years has been the JJ 6L6 , time will tell, but I think
I like the tung sol better ,
For the last couple of years the JJ 6L6's I've got seem more undefined then before.
Maybe they changed them ... or maybe my tastes changed?