NVD (New Valves Day)

earwighoney

I finally got around to putting in the new valves I bought a few weeks back into my Fender Blues Deluxe, which I believe hadn't been revalved since it was made!  Which I think was the early 90's!  

An understatement to say the amp sounds a lot better now than before.  Reasonably pleased with the slightly unusual configuration of valves I went for which is as follows 

Power - JJ 6L6GC's
V1 - JJ 12AY7
V2 - NOS MIC 12AX7 (6N4?)
V3 - RFT 12AT7

The clean channel is much more controllable with the 12AY7 in V1, opposed to the 12AXY from before.  Had a quick go through the dirty channel and the new 12AX7 is alright, not great though but it doesn't matter that much as I barely use the dirty channel. 

Maybe not the most astute observation but I can't believe how much of a difference a fresh set of valves makes.  It was the first time I have changed valves on an amp as well and my fear of changing valves was definitely irrational. 

ICBM

Bear in mind that the difference in valve *type* - especially the 12AY7 in V1 - makes more difference than the valve *quality*. Although that's not to say that the old valves weren't worn out and new ones of the same, or the same type but different brand, wouldn't have made a difference too.

Also bear in mind that all three preamp valves are used on both channels - it's not that one valve is for each channel on this amp. All the 'channel' switching does is to change gain levels at a couple of points in the circuit. Even on the Hotrod, both channels go through all six valve halves apart from the second half of V2, which is exclusively on the drive channel.

That's still the valve order/combination which seems to work best in this amp though, for me.

earwighoney

ICBM said:

Bear in mind that the difference in valve *type* - especially the 12AY7 in V1 - makes more difference than the valve *quality*. Although that's not to say that the old valves weren't worn out and new ones of the same, or the same type but different brand, wouldn't have made a difference too.

Also bear in mind that all three preamp valves are used on both channels - it's not that one valve is for each channel on this amp. All the 'channel' switching does is to change gain levels at a couple of points in the circuit. Even on the Hotrod, both channels go through all six valve halves apart from the second half of V2, which is exclusively on the drive channel.

That's still the valve order/combination which seems to work best in this amp though, for me.

Thanks for the reply Mr ICBM, 

Good to hear my choice of valves is the one which best for you as well.

Yeah the old valves were in a terrible condition.  I bought the amp second hand in the late '90's and it hadn't been revalved since then and there's a chance the original ones were in there. 

Thanks for the info about the preamp valves being used across both channels. The NOS 12AXY I put in, I tried in my Ibanez TSA5, and it was alright but the amp definitely sounded nicer with a JJ 12AX7 in it (I know you're not the biggest fan of that particular valve!) 

Maynehead

The power valves probably made a lot of difference. Worn out power valves can make an amp sound flat, boxy and generally terrible. Different preamp valves just give a different flavour.