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Diabolical Artificer · 11th May 2022, 6:06 am

Try the 12AT7, just be careful with your layout, it may not oscillate. There's not many dual triodes with a u of 70 apart from the 6SL7 but that's octal. There's a few valves with dissimilar triodes in which would be great for a preamp but non I no of with a gain of 100/70, most are low gain high current triodes for use in TV's, so try the 12AT7, you might have to up the grid resistor value a bit.

BTW, the tone controlI linked to is by-passable.

Andy.

11th May 2022, 6:06 am	#20
Diabolical Artificer Dekatron Join Date: Jul 2009 Location: Sleaford, Lincs. UK. Posts: 7,657	Re: Thoughts on this HiFi line amplifier? Try the 12AT7, just be careful with your layout, it may not oscillate. There's not many dual triodes with a u of 70 apart from the 6SL7 but that's octal. There's a few valves with dissimilar triodes in which would be great for a preamp but non I no of with a gain of 100/70, most are low gain high current triodes for use in TV's, so try the 12AT7, you might have to up the grid resistor value a bit. BTW, the tone controlI linked to is by-passable. Andy. __________________ Curiosity hasn't killed this cat...so far.