crack otl tube got really hot

[fightever2010]

Hello all,

I recently got my crack otl assembled. I was very excited to test it out. But I found that main tube got super hot soon after I turned on the power. Is this normal or did I do something wrong in the circuit?

Thanks!

[Paul Joppa]

It should get about as hot as a 25-watt incandescent light bulb, since it's more or less the same size and dissipating about the same heat. The power transformer will also get warm, thought that might take a few hours.

[fightever2010]

I see. That makes sense. Thanks a lot!

I am thinking about installing a fan next to the tube to cool it off. Do you think that will increase the lifetime of the tube?

[Natural Sound]

I see. That makes sense. Thanks a lot!

I am thinking about installing a fan next to the tube to cool it off. Do you think that will increase the lifetime of the tube?

Probably wouldn't hurt. I for one though hate any kind of fan in my listening area. Even the computers used in my music server are fanless.

Make sure you read Doc B's thread "from the bench." He talks about the rubber feet on the bottom of the wooden base being manditory to achieve proper cooling. Make sure yours are installed. That being said the crack amp runs hot. It's nothing to worry about.

http://bottlehead.com/smf/index.php?topic=9184.0

Edited to add above link.