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Dissipate heat, which?

Discussion in 'Amps and Cabs [BG]' started by Rod B., Oct 14, 2004.


  1. Rod B.

    Rod B.

    Jun 11, 2002
    Montana
    Which is better to have in order to dissipate heat, the pre power right above each other or separated by a space in the rack? I think remember seeing somewhere that separating them trapped heat, but I'm not 100%.
     
  2. IvanMike

    IvanMike Player Characters fear me... Staff Member Supporting Member

    Nov 10, 2002
    Middletown CT, USA
    seperating the two is not going to trap heat as much as having the preamp right on top of the poweramp. In general the poweramp is going to have more of the heat issue so placing it on the bottom with space above it is the best bet. Preamps generate some heat, but not all that much.
     
  3. Rod B.

    Rod B.

    Jun 11, 2002
    Montana
    Thanks. What I remember seeing (a little foggy, too much fun in the 70's probably) was by putting the pre right on top of the power sorta made the pre into a heat sink. But if it did, I was thinking that kind of heat could be bad for the components of the pre.

    So, I wanted more opinions than my own sometimes flawed logic.

    Thanks again.
     
  4. IvanMike

    IvanMike Player Characters fear me... Staff Member Supporting Member

    Nov 10, 2002
    Middletown CT, USA
    Only a little bit..............
     
  5. Jerrold Tiers

    Jerrold Tiers

    Nov 14, 2003
    St Louis
    It's worth remembering that heat rises......

    Putting a hot poweramp under the pre usually heats the pre more than putting the poweramp on top.

    Of course, a tube pre already gets hot. But there's no sense turning up the oven.

    Poweramps that have such hurricane-force cooling that the case doesn't get hot won't cause a problem. You can put preamps above them OK, at least as far as heat is concerned.

    Logically putting the heavy things on bottom makes sense for carrying and not being top-heavy.

    The one problem with some poweramps is the magnetic field from the power transformer. That can induce hum into a piece of equipment such as a preamp. Even toroidal transformers, if not made right, will "leak hum". A little space between usually cures that.

    Directly answering, I'd leave the space. That allows air flow over the top of the amp, and lets heat dissipate a bit better.

    Sticking them right together will "trap the heat" more.
     
  6. Rod B.

    Rod B.

    Jun 11, 2002
    Montana
    Thanks Jerrold!