6sn7/6sl7 advice please

[lordmortlock]

I've been running an Almarro a318B for a month or so now. God it's good ... it does that SET holographic thing but with punch, hit and slam of almost SS proportions. A keeper! :)

Now the fine tuning begins. My Art Emotion monitors are capable of getting a tiny bit shrill up top with some pieces so I'd like some ideas as to best valves to just 'darken' the sound a little. The amp uses 6c33c power valves so not much I can do re rolling there so my thoughts turn to the two small valves - a 6sn7 and a 6sl7. I'm using the Black treasure Cv-181 in place of 6sn7 and that's wonderfully open but the amp does that pretty well already.

Any advice on this please chaps? Concious that we're only talking a degree/percent or two in change but thats pretty much all it needs.

Thanks, Jake

[Reffc]

I've been running an Almarro a318B for a month or so now. God it's good ... it does that SET holographic thing but with punch, hit and slam of almost SS proportions. A keeper! :)

Now the fine tuning begins. My Art Emotion monitors are capable of getting a tiny bit shrill up top with some pieces so I'd like some ideas as to best valves to just 'darken' the sound a little. The amp uses 6c33c power valves so not much I can do re rolling there so my thoughts turn to the two small valves - a 6sn7 and a 6sl7. I'm using the Black treasure Cv-181 in place of 6sn7 and that's wonderfully open but the amp does that pretty well already.

Any advice on this please chaps? Concious that we're only talking a degree/percent or two in change but thats pretty much all it needs.

Thanks, Jake

Hi Jake

try NOS RCA 6SN7s. Not as oomphy as something like the EH6SN7s and a little more rolled off IME but that may be just the ticket. Depending in the circuit you may not get much change from valve rolling sound-wise. You might be better increasing the value of the series resistor in the HF portion of your crossover just to tame down that HF output a little. A room analyser should help pinpoint the troublesome frequency lift so that a more educated guess a the resistor value can be made. Happy to help if needed.

[lordmortlock]

Morning Paul

Was going to call you later for a chat! I had RCA ecc82 on pre duties in my old Oto and that displayed the same character. Sounds like that might be the case for RCA generally? Worth a try - I'll get hunting. Any experience of Mullard Ecc35? I understand thats a drop in for 6sl7