Use a 6fq7 instead of a 6sn7 in Cornet2

rotcoddam · « **on:** 8 Mar 2005, 06:25 am »

I was planning to do the hybrid mod and my brother in law asked why not just use the 6fq7 instead. Anyone try this? It seems I could leave the socket in, cut the trace between pin 4 and 5, and run a wire from 9 pin to 5. Oh, and change the appropriate resistors. This is a really nice sounding tube. Any opinions?

GRD · « **Reply #1 on:** 9 Mar 2005, 12:04 am »

Interesting idea. Might make the socket problem easier to handle. The 12BH7 is another interesting tube, and I think it has the same pinout as the 12au7. Don't have any experience on how these alternative 9-pins would sound.

rotcoddam · « **Reply #2 on:** 9 Mar 2005, 12:27 am »

I opened my amp and it looks like I'll have to isolate pin 5 from pin 4, then run a wire from pin 4 to r215r. Then run a wire from 9 to 5. I will probably use my Dremel and a steady hand. No beer drinking during this mod. I have the 6fq7's in my Heathkit w-5m's and they sound really good.
I wonder if it would be easier to just install the octal socket?

rotcoddam · « **Reply #3 on:** 11 Mar 2005, 01:57 am »

Just finished the 6cg7 socket modification. It was easier than I thought it would be. I used a razor knife on the traces and scraped through the copper (using a magnifying glass). I didn't want to use a dremel and make a dusty mess. Or risk letting it go out of control!
Anyway I stuck an old RCA in there and wow, was I impressed. more life, more dynamics. This is a highly recommended mod for the Cornet. Now for tube rolling...again.