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Spare tubes? How many?

Being the anal sort of worrier that I can be, I'm thinking to buy some back up tubes. 4 KT88s, 2 12AX7s and 2 12AT7s in place now. I believe only the power tubes are really prone to fail. Welcome correction if I am wrong in that assumption. Should I buy 1, a pair or a complete Quad set of KT88s. If only one tube fails (assuming no sort of catastrophic fireworks) can you simply replace the single and re-bias? Will that make everything OK? (tubes were purchased from the Tube Store so are matched and have the matching number). Thanks for the input.
GH
ghosthouse
sugarbrie
3,854 posts
 
I guess I am an tube hog... :-)
I have four extra pairs; but they are vintage 1940's tubes so worth keeping...
tbg
5,263 posts
 
I have always found that 1940-1970 tubes are unequaled by newer tubes. Years ago I began buying good buys on a broad range of miniatures as well as output tubes. I have nearly 1000 tubes. They have been a great investment, even though now I use both a solid state amp and line stage. Tubes that one could buy for $8 in 1970 now sell for hundreds of dollars, some for more than $1000.

It is one of the costs of using tubes that you need to have a reserve stash.
kurt_tank
1,188 posts
 
Wow!

It is great to see that I am not the only one with a sh*t load of extra tubes.

Luckily, I have a Lamm hybrid amp (M2.1), which only uses
one 6922 tube in each monoblock.
But to make up for the fact that I only need two tubes, I have the following pairs of tubes:

The stock Sovteks;
Two pairs of inexpensive new tubes;
Two pairs of medium priced NOS tubes (Orange Globes);
And, one pair of expensive NOS tubes (Pinched waist);

6 pairs of tubes which supposedly will last me a couple of thousand hours per pair.

6 pairs x 2,000 hours = 12,000 hours.

12,000 hours divided by my average of 4 hours per week (which includes an hour of warm up time) for my listening sessions = 3,000 weeks

3,000 weeks divided by 52 weeks a year = 58 years.

My conclusions from my calculations are:
One, I am not listening nearly enough!
Two, I have way too many pairs of tubes!
And Three, apparently my daughter, who will inherit my gear, is set for life too!

PS Anyone know of a cheap (and reliable!) place to buy more NOS tubes?

:-)
tbg
5,263 posts
 
Kurt, I used to know of several. They are all gone now. Most of the Western Electrics are in Asia now, as they appreciated them before we did.
elizabeth
6,726 posts
 
WOW you guys are as bad as the vinyl crazies!
(spare copies of the best...)
I am deep in contemplation of a Dared tube job.
i cannot decide if I should go with a Dared pre @ $600. and stick it in my system. Or go with a pair of the $1K 300B single ended amps...
(I have B&W 805s and NEVER play loudly.. )
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