I'm looking at building a guitar amp that may have to have its power tubes oriented horizontal or upside down. Now, I've had amps with the spring-and-cap retainers and also the Fender-style base-clamps. I've never been a fan of the spring ones, as they have a contact with the glass and can induce some noise, or uneven envelope heating (by my reasoning). And the Fender one's always damage the plastic bases on tubes, which is only an aesthetic problem. Still, does anybody have a favorite type of retainer?
