Tube preamp top clearance--McIntosh or in general


Does a tube preamp really need 6-inches of top clearance?
Specifically, the McIntosh C2300, already 7+ inches high,
according to the manual, needs 6 inches clearance. Thats 13+ inches, unusually high for a rack shelf that is not
the topmost one (mine at least). There are 6 12ax7 tubes.
Any thoughts? Thanks.
rgs92
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.)
I have owned my C2300 since January and think it is very good. I am using Mapleshade Triplepoints underneath it and there is just an inch above it, but my rack is open on all 4 sides and heat build up is not a problem. In fact, the top barely gets warm after extended listening sessions. Now my Mc275 is a different story...

I really like this preamp and its built in MC phono stage. I have replaced the stock tubes with Telefunken smooth plates in the line stage and the MC phono stage. Overall it is extremely quiet (even the phono stage) and has a rich character with nice detail and dynamics.

Personally I find the blue meters distracting and as a result they stay off in my system. But I do appreciate the easy user interface including changing the phono settings on the fly with the remote.

Dave
If you remove the top/any covers(not the bottom plate) from the pre-amp: it'll stay cooler. I've always done that with tubed gear. Never have had a problem with tube longevity, even though my gear has always resided in an enclosed, rack type cabinet(not the power amps). Pearl Tube Coolers also will help. Page 16 in this catalog: (http://www.percyaudio.com/Catalog.pdf) If the pieces are very close together RFI/EMI shielding is a good idea(See page 14 for Texas Instruments shielding). There's a sheet of it somewhere, between every piece of my equipment.
Thanks for the ideas.
Tricon_dave,
any comments on the C2300 sonics for linestage use (not phono)? Does it have that nice (to my ears) warm, liquid, relaxed Mac flavor but still definitive with no part of the spectrum exaggerated or supressed? (Even though it's not the last word in dynamics or slam.) This is my take on the C46 preamp I now own.