6L6 GC STR440 or STR 430

[Taff Strat Boogie]

Hi Guys,

Newbie to the board here! Sorry, but this was originally posted in the F Series section of modern era amps and may have been better in the Tubes section!

I've just picked up a used F50 from eBay and the sound from my latest purchase appears to be perfect for what I play (soul, funk, blues etc) and has the stock Mesa Boogie STR 440 power tubes fitted. I also inherited a matched pair of STR 430s and a full set of brand new JJ 6L6 GC's with ECC83 S's (x4).

My query is.....

a) Are the STR 430's compatible with the F50 and what are the differences (if any) to the 440's?
b) Also, not having previously tried JJ tubes, how do they compare (sound wise) to the Mesa tubes?
c) What's your best advice.... just change the whole set to JJ's, or maybe just try the power tubes initially?
d) The lead channel appears to be be a little too "aggressive" for my usual tastes and I wondered if anyone out there has any ideas on "taming" it..... maybe resulting in a little mellower/less gainy sound?

Hope you can help out?

Cheers

Brian

 

[zodiac272]

hey, welcome

the mesa str 430's will work. if your amp takes 6L6gc's, any mesa 6L6 will work. I think the 430's are better tubes than 440's but I have no experience with them. A/B both and let your ears decide.

As far as preamp tubes, maybe put a Mullard 12ax7 in V1 or find some NOS tung sol for it. If you want to tame it a bit more, find a 5751 12ax7, which have about 70% of the gain of a regular 12ax7. I'm sure you can get a less aggressive sound by turning your preamp gain down a bit too. I would recommend tubes other than JJ, but I'm not speaking from experience, just what I have read.
hope this helps a bit


Scott

 

[Taff Strat Boogie]

Hi Scott,

Many thanks for the info....... it's much appreciated!

I think I've managed to work out that the STR430 is the 6L6GC version before the current 440 and is currently unavailable or in short supply with most suppliers (probably ceased production). If that's the case, I therefore suspect that the 430s were the original power tubes supplied with the amp (and may be dull/lifeless) and the 440s have in fact been bought since as replacements.

I've heard a few recommendations for the 5751 preamp option and may well investigate that avenue further.

You're "bang on" with your suggestion that both power tube sets should be A/B'd....... but like most musicians, I've become lazy with regard to experimenting and fallen into the trap of asking other musos to come up with a quick or cheap fix for me to get to where I want to be (tone wise)! :lol:

Once again, many thanks for the response!

Best wishes

Brian