Tube preamp top clearance--McIntosh or in general

Wow...if that is for the preamp, then what do the recommend for their tubed amps....I guess you had better have a high ceiling if you ever buy one their amps :-)

The heat dissipation for tubes is important to ensure a normal lifespan for them. If it cannot be ventilated by natural convection currents, the very hot tube becomes hotter and this is detrimental to the filament etc.. In most applications the damage occurs over time.
IMHO it should not take that much space, my preamp for instance, uses 6 12Ax7S running at full voltage and has a highly ventilated cover. It is an ARC which uses these covers. If you have seen most any ARC tubed gear then you recognize this method of ventilation. It requires about 4 inches of shelf space just for the air.
The proof of the pudding is in the eating (not "in the pudding" ) All of the original tubes are strong and functioning perfectly, this is an old preamp.

OK, I found this in audiokarma on my own question here,
in case anyone is interested.

http://www.audiokarma.org/forums/showthread.php?t=140181

Thanks for the replies.

(Any comments on the Mcintosh C2300 preamp are also welcome, too.)