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Who's Gone Topless?

The idea of this goes back decades. Amps and preamps (for the most part) are designed on chassis free breadboards, then voiced, THEN are packaged inside a chassis, which can be the weakest link to hearing what the designer intended. In most cases the chassis sidewalls and bottom are essential, but the top?


First off, beware that doing so will likely affect your mfg warranty, but, if you live in a pet-free, child-free home, then the benefits can more than offset concerns about something getting in that could harm the components. Case in point my Ric Schultz Class D EVS 1200, dual mono IcePower 120as2 modules. HOWEVER, unlike others using the same or similar modules, Ric then sprinkles many decades of modifying pixie dust all around them which are mounted inside an understated (sans bling) Italian sourced chassis.

When I ordered mine it was mandatory to purchase 2 Cubes ($200) which are to be butted up against each board, requiring the owner to remove the top. After doing so, I was anxious to put it in my rack so I could properly isolate it from bad vibes, when I should have listened with and without the Cubes and top.


Ric is also a proponent of weighing down components, but due to the unnecessarily large chassis, it barely fit in my rack, but I had a 5 pound divers belt lead weight that I squeezed in. Now, because RIc chose to put the mute toggles on the back I placed the amp on the first shelf from the rack's top (but out of sight out of mind: I never mute it when done listening), upon which was my CD player/Transport, which I raised up to provide ~ 2" of air space above the top of the 1200 and the bottom shelf of the player. Even though the rack is open on all sides with plenty of air space all around the rack, the amp ran warm

Fast Forward to yesterday. I was listening to Leonard Cohen Essential songs, mostly instrumentally sparse. I removed the weight; and found the music much more open sounding. Encouraged, I FINALLY removed the top. Honestly, I was not prepared for how HUGE doing so could be. It was like the music went from a confined space to an open air 3 dimensional venue. This is so amazing that I am going to get a handle on it via different music before removing the Cubes. Oh, and the amp is now cool as can be. 


So, if interested, stay tuned
tweak1
tweak1 OP
3,645 posts
 
Yesterday afternoon I took the cover off my 105


Nothing like the crazy opening up and improved SQ that removing the lid and Cubes did


BUT micro-details are now evident. Examples; when a snare is being brushed, and the handle is used to gently tap the rim and skin, I actually heard the skin vibrate!, or when a singer starts to sing in a low voice, the first syllable is more easy heard and understood, and more separation of the instruments/singers

As always YMMV


hth
tweak1 OP
3,645 posts
 
@glupson I did not find an exact 14 x 17, so I settled for a 20 x 20.  I simply place it on top of my rack, which leaves a small amount of air space, but this filter is a micro for preventing dust from passing, but, it does keep most off the heat in, so I am only using it when done playing, I mute the modules and put the filter on top. I plan to get to a hardware store to see whether they have fiberglass filters which are more porous, and so will let more heat escape so I don't have to mute when done playing
+1 lwal22  Thanks.


The naysayers don't bother me. I am confident that I know what Im hearing- good or bad, but in this case exceptional. The best part is it costs NOTHING to try. Oh and dark chocolate takes it to another level of satisfaction ;)
danvignau's avatar
danvignau
935 posts
 
The three amps in my system are not topless, but they are separated by two inch spacers, and are in a different room from the speakers.  Since they do not run hot, barely even warm at 400 watts per channel with two ohm loads, I wonder why so many systems run hot.  Also, can sunlight  add a bit of openness.  Is an incandescent, halogen, mercury, LED, or fluorescent better?  Should we use a newer digital ballast, or an old school dinosaur with the starter cap? Should my bass amp have the same light source as the amps for the tweets and mids?  Oh yeah. LED's are digital Scratch them.  How about old school for tubes?  Maybe candles, a gas fireplace, or even a Coleman lantern?  Do I use different light sources on my $500 power cord?
danvignau's avatar
danvignau
935 posts
 
middlemass:  South Florida heat?  Do you not keep your house at a consistent temperature?  Do your neighbors mind having your windows open when blasting away the music?     I would certainly go topless for tubes. You should have seen the ventilation holes that surrounded family's movie theater two and a half foot tall tube amp, GE, I believe?

danvignau's avatar
danvignau
935 posts
 
1wal22:  Yes, good weed is really the best sound stage opener, especially with a single malt, at least for most music.  Johnny Walker cinnamin is good for blues, and supposedly country rock, expept for Lennard Skynard:  I am told Fireball is the best for that. 
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