[Jean Beaudoin]

Hi,

I have Heathkit AA-50, one of 7591 tubes is burn.

I have several possibilities but what is the best option:

1 - Replace the 7591 burned tube by a new one (7591A) ?

2- Replace only the pair set (right) by 7591 A Matched Pair?

3 - Replace all of 7591 tubes (left and right) by four 7591 A (matched
Quad)

Should I replace also two 7199 (original heathkit tube) tubes by new pair?

Triode store online is the best to by a new tubes?

Thank's a lot
Jean Beaudoin

[Jon Yaeger]

in article , Jean Beaudoin at
wrote on 5/5/07 1:50 PM:

Hi,

I have Heathkit AA-50, one of 7591 tubes is burn.

I have several possibilities but what is the best option:

1 - Replace the 7591 burned tube by a new one (7591A) ?

2- Replace only the pair set (right) by 7591 A Matched Pair?

3 - Replace all of 7591 tubes (left and right) by four 7591 A (matched
Quad)

Should I replace also two 7199 (original heathkit tube) tubes by new pair?

Triode store online is the best to by a new tubes?

Thank's a lot
Jean Beaudoin



I would replace the one with a matched pair. I would replace the other set
too if one or both measured bad or weak or if the pair were no longer
"matched." The best bet, sonically, would be to replace all with a matched
quad, but that is going to be a more expensive proposition.

Triode is a good place to buy tubes. I have had bad experience with Russian
7591 replacements, and wouldn't buy any more. I have heard the JJ Teslas
are OK. But IMHO nothing beats NOS Westinghouse or Sylvania 7591s . . .

Jon