MacKlipsch Posted February 5, 2001 Share Posted February 5, 2001 Have an old mac tube amp that I want to connect to my mac C-15 preamp, but there is no switched outlet on the back of the C-15. It was recommended that I get an outboard unit to accomplish this. The local Hi-fi store guy says he leaves his tube amp on all the time, unless he is gone for multiple days. He claims that this doesn't effect tube life and that the power used at idle is neglegable. Anyone have the scoop? Quote Link to comment Share on other sites More sharing options...
Al Klappenberger Posted February 6, 2001 Share Posted February 6, 2001 Mac, I say HORSE-HOCKEY! Tubes make too much heat to be left running. Tubes are expensive so why let them sit there and cook. The only reason to leave it on is a thing called cathode stripping. If B+ goes on before the filement is hot, the oxide coating on the cathode is slowly striped off. This happens when it is first turned on. So, it's really a trade off. I would turn it on and off myself. Good tube units have a delayed B+ so this does not happen. Al K. Quote Link to comment Share on other sites More sharing options...
Spider124 Posted February 6, 2001 Share Posted February 6, 2001 Also, unless your amp has a soft-start circuit, every time you turn it on, the filaments get stressed. So some people leave thier small-signal ones, like in pre-amps or DACs on all the time. But with a power amp, sure if you're gonna listen to it again that same day, you might as well leave it on, but I'd never leave the house with them on, or keep them on overnight. Charlie Quote Link to comment Share on other sites More sharing options...
J M O N Posted February 7, 2001 Share Posted February 7, 2001 Don't leave your tube amp on all the time. You will be replacing tubes often if you do. Quote Link to comment Share on other sites More sharing options...
MacKlipsch Posted February 7, 2001 Author Share Posted February 7, 2001 I called the Macintosh technicians today and they basically said the same thing. Any benefit that would be gained by not having the amp turned off and on would more than be lost in tube life. Mac has a unit called a PC-4 that goes for under $100 that daisy chains from the Mac switching plug on the C-15 to the Mac 202 that has 6 or 7 switched ac plug on it. Going to order it. Seems the best plan. Thanks everyone for your help... Quote Link to comment Share on other sites More sharing options...
KenB Posted February 9, 2001 Share Posted February 9, 2001 Ditto with the statements above. Plus amps do draw a bit of power = extra dollars, and tubes lose there oomph as their lifetimes come to an end. Gee, kinda like people. The only exception would be if you could leave the tube filaments alone always on. Again, it's all the turning on & off an on that kills the getter (stripping). -Ken Quote Link to comment Share on other sites More sharing options...
Al Klappenberger Posted February 9, 2001 Share Posted February 9, 2001 KenB, You hit on something there. Rmemeber instant on TV sets? They let the picture tune filament run at about half normal voltage, then powered them up full when the set was turned on. That requires the switch that Mac is missing though, so it's sort-of a moot point! Al K. Quote Link to comment Share on other sites More sharing options...
KenB Posted February 10, 2001 Share Posted February 10, 2001 Al, I had an instant on TV, it went up in smoke while OFF---uh half on! I think that concept was a safety issue...so the half-ons were taken all-off in the end. -Ken Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.