Tubes to replace stock in Quad II Forty's amps?


Have a pair of Quad II Forty amps and have decided to retube them in an effort to get rid of some intermittent hums and pops. Great sounding , want to them to sound even better.
I have ruled out GEC 's and such , as money is sort of an issue. Svet's, SED, EH, KT88's , KT90's? Etc.. Ideas. Also, will the brand of rectifier tube(5U4G) make difference in overall sonics?
Lastly, will the input tubes 6SH7 matter in the picture.I been told to suspect these as a source of pops and spitting noises on rare occasion.
Thanks, again. I am new to the world of tubes.
montyoldboy
SOVTEK makes very good KT88 tubes & do not forget GROOVE TUBEs KT88s.

The 6SH7 input tubes are supposed to be millitary grade! Gha! Get something with a glass envolope like TUNGSTRAM or ELECTRO HARMONIX.

You do get better 5U4G rectrifiers also from SOVTEK & GROOVE TUBE. Do check out GROOVE TUBE - they hand-match their tubes to very fine tolerances.

Kind Regards,
Dewald Visser
Will an input tube 6SH7 in this case, take out anything if it goes bad or is bad in an amp? I am worried and hope to get some NOS ones off ebay.One seller has untested NOS military 6SH7GT. If these are bad will they destroy some other component down line in my already troubled amps? Thanks
Avoid untested tube unless you can test them before you put it in your amps! A faulty input-tube can destroy a power-tube... Be very careful!

Regards,
Dewald Visser