The Luthier Community

Rich Schnee wrote:I have never treated my Tubes as if they were Halogens. What is the theory behind that?
It’s good practice to install a bleeder resistor across the caps. I do it when ever I work on an amp as a safety measure for whom ever works on it after I do.

Yup, I use a 25k 10 watt power resistor and ground out both cap leads with that - No lightning, no scary, just drain 'em.

The halogen thing comes from the fact that high temp and current can be tough on glass as well as internal components; don't touch 'em and you deposit no oils, goo or other contaminants that could get hot faster than untainted glass and cause premature failure problems for those tubes.

E

I’m really not trying to be argumentive but, I just don’t subscribe to the notion that finger prints on halogen bulbs cause premature frailer. My under cabinet lights are halogens and burn out often. I have installed those wearing white gloves and have even tried washing them with dish soap and still they burn out at about the same rate.
In my opinion…heating and cooling is the route cause of most electronic devise failure, especially in tubes. When they get hot, the plate, filament and grid expand and when they cool they my not go back to where they originally were. Repeating the process will change the tubes characteristics and dramatically change the way the amp sounds. Even if you leave your amp on all the time, eventually the plate will deteriorate and the heater will burn out.

Sorry for the tangent…Rich

No worries, good to discuss, Rich -
Now I don't necessarily disagree with ya, but in talking to some techs and keeping in mind that tubes carry far more voltage through them and do indeed run inherently hot, it never hurts to be careful - I've been ingrained in the don't-touch-the-tube school since the 60s, so I'm a creature of habit!

E

Good work Eman,

When you had only changed out the speaker I was a little surprised because whilst I did like the Celestion better than the original when dirty, I preferred the original when played clean. Once you changed out the tubes, that seemed to really lift the whole game and the over all improvement was huge. Thanks for the efforts to post this stuff.

Hey thanks Kim, and my pleasure - And real glad somebody other than me can hear the changes!



E

First, I pretty much skimmed over things and then went straight for the tune and speaker change specs and audio files. More detailed reading and note taking later on when I get ready to re-tune my '63 Super. So thanks for all your work here Eben.

The speaker swap seemed to give a bit more definition to things with my ears, and this is never a bad thing. Tube and speaker swaps did produce a fatter/warmer sound, both clean and dirty. Now, if I were a chicken pickin fool with a Tele, I'd want some of the twangy top end back. Alas, I'm not. For blues and most other stuff, give me the fat/warm sounds any day!

Yep, that's exactly what I'm after with this change over -
Note that pickups on both Strat and Tele are stacked buckers...
I'm way happy with it!



E

Oh, and for transparency and in the interest of science;

The clean takes were all bridge pickup only,

The dirty was all 3 pickups on the middle switch point, of course.

E