Has anyone tried swapping the traces under your PC-3 and then using the 6u8a in place of 7199?
4 posters
Has anyone tried using the 6u8a in place of 7199?
j beede- Posts : 473
Join date : 2011-02-07
Location : California
Sal- Posts : 221
Join date : 2009-02-05
Location : Central New Jersey Dynaco-ST70.com
I have not swapped the traced on the printed circuit board but I have used the 7199-6GH8 adapter sold by Dynakitparts.com. The ST-70 is happy with a 6GH8 tube.
Sal
Sal
anbitet66- Posts : 143
Join date : 2009-12-23
Location : Valley Stream, NY
- Post n°3
Re: Has anyone tried using the 6u8a in place of 7199?
by anbitet66 Thu Jun 09, 2011 11:55 am
If you look at the schematic for an ST-70 series 2 it uses a 6GH8 with only 2 different capacitors in the circuit. According to what I have read about 6U8A, it is even closer to the characteristics of the 7199. If you don't want to cut and rewire for a test, the plug in converter mentioned by Sal will aslo work for the 6U8A tube.
Or, to not have to buy the adapter, you could theoretically make your own by removing the envelope of a 7199 and carefully attach a socket to the base to plug in a 6GH8/6U8A as a test...
BTW I'm kidding; don't try this at home kids! I'm a professional. Tony
Or, to not have to buy the adapter, you could theoretically make your own by removing the envelope of a 7199 and carefully attach a socket to the base to plug in a 6GH8/6U8A as a test...
BTW I'm kidding; don't try this at home kids! I'm a professional. Tony
wolverine- Posts : 59
Join date : 2010-02-20
- Post n°4
Re: Has anyone tried using the 6u8a in place of 7199?
by wolverine Sat Jun 11, 2011 7:50 am
I purchased two of the socket converters and use them on one of my ST-70's. The board is a new one, but exactly as the original 7199 board. I used two NOS Sylvania 6GH8A tubes and it sounds fantastic to me.
wolverine
wolverine
Sponsored content