5AS4 sub for 5U4

[gingertube]

NOS 5U4 are "rare as rocking horses ..." and new production are expensive.

NOS and used 5AS4 are dirt cheap - the data sheets suggest it should be fine BUT the only place I've actually used a 5AS4 in place of the 5U4 so far is in a Fender Bandmaster Guitar Amp where it worked fine.

Anyone tried this sub in a HiFi Amp? Comments?

Cheers,
Ian

 

[Colt45]

It's the same tube, as far as I recall.


I remember seeing old GE tubes labeled 5U4/5AS4 right on the glass...

 

[gingertube]

Data sheets I have suggest 225mA for 5U4 and 275mA for 5AS4. Otherwise the specs are the same.
That is the 5AS4 is an uprated 5U4.
Cheers,
Ian

 

[Colt45]

Go for it then. more current, less price. groovy.

 

[NickC]

dude
5u4 are so easily available. I have like 32 of them in my box of tubes. If need some let me know then

Cheers
nicholas

 

[Eli Duttman]

NOS 5U4Gs are fairly scarce. Current production Chinese and Russian 5U4Gs SUCK.

Supplies of NOS 5U4GBs are reasonably plentiful. TungSol, RCA, and GE are all GOOD choices in 5U4GBs. I've yet to see any feedback on the relatively recently introduced Russian 5U4GB.

If you a willing to use a UX4 socket instead of an Octal socket, the 5Z3 is electrically equivalent to the 5U4G.

 

[planet10]

I have like 32 of them in my box of tubes. If need some let me know then

I've got a box of 'em too... not quite that many thou.

dave