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MC 240 ReTube or Replace

About a year and a half ago I acquired an old McIntosh MC 240.

I replaced the capacitors and retubed it using:

Genalex Gold Lion 12AU7 gol

Genalex Gold Lion 12AX7 gold

Tube Amp Doctor TAD 12BH7

TUNG-SOL 7581A

 

Now after some 1,000 hours of operation, driving a pair of Salk SS 6m speakers, one channel will intermittently give out a blast of static within minutes of power up and blows the fuse. This leads me to believe I have a tube which may be intermittently shorting.

 

With the MC 240 being almost 60 years old I’m wondering if modern technology has surpassed it.

Thus, the question retube or replace it.

 

Currently my choices are:

Quick Silver 60 watt mono amps

Mc Gary Audio SA 1

Van Alstine Vision SET 400

 

I would appreciate any comments.

TNX



pelletfan
artemus_5's avatar
artemus_5
1,917 posts
 
I doubt that amp technology has changed very much. There is better parts available today. But you're already replaced some parts. A set of tubes is much cheaper than an amp.  BTW I really like the 7581 tubes.
oldhvymec
5,101 posts
 
Mcintosh MC240 is one of the best sounding amps around.

You rebuilt the power supply? Did you replace the filter caps and resistors to bias the unit correctly. Loosing a valve is easy to check. Swap left to right on the power tubes after giving them a GOOD visual. Same with the small valves, swap left to right.

3-5000 hours on power valves, 7-10,000 for the small valves. BUT valves do fail.. No matter who makes the gear.. No matter who makes the valves.

Regards
stereo5's avatar
stereo5
6,290 posts
 
That McIntosh amp is a classic.  If it were mine, I wouldn’t sell it.  They go for big bucks at AC. 
jond's avatar
jond
5,706 posts
 
Don't sell it retube it and if necessary do additional work on it, it's worth it.
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