[R-390] PEARL Tube Coolers

[Roy Morgan]

At 10:28 PM 3/14/2004 -0500, ToddRoberts2001@aol.com wrote:

>Hi All, Dave Ross's recent question reminded me that I wanted to ask the
>group if anyone has had any experience with the PEARL tube coolers? I see 
>they are
>popular with some of the Hi-Fi crowd.


Todd,

<Spoof mode ON>

Yes, get them for all your tubes. They increase the sound stage image 
immeasurably and add a definite sense of presence and airy ness to the 
sound while removing a sort of graininess found in lower quality 
equipment.  While you are at it, get some Cocobolo wood pyramids to mount 
your equipment on.. it reduces interference from the dreaded intergalactic 
noise field and cannot be done without. Only six hundred dollars a set of 
four.  And have you heard of the cryogenically treated hospital grade 20 
amp outlet sockets? None better. You have to try them to understand the 
improvement.. Only $40 each.  The accompanying cryogenically treated power 
cord is a mere $150. ...

<Spoof mode OFF>

in my opinion:

Those tube coolers might work a bit better than IERC or similar tube 
shields in cooling the tubes*, but if I were you I'd spend my money** on 
spare tubes and normal heat dissipating tube shields, and a FAN!

*For a dissertation on their performance, including a very interesting 
bibliography on the topic, see:
<http://www.pearl-hifi.com/06_Lit_Archive/01_Audio_Notes/PEARL_Tube_Coolers.pdfv>
By the  way, this reference shows a chart of tube temperature vs. cooling 
air velocity for a number of tube shields, including the shiny chrome ones 
and the black IERC ones.

**It appears that you can get Pearl tube coolers for small tubes at about 
$6 each.  See:
<http://sphl.audiogon.com/cgi-bin/buy_cl.pl?accstube&1083100833>

Roy



- Roy Morgan, K1LKY since 1959 - Keep 'em Glowing!
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Home: 301-330-8828 Work: Voice: 301-975-3254,  Fax: 301-948-6213
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