The Chromegas have dedicated timers made for the color head. The light bulb condenser units are hooked to various electronic timers. The cold light needs a mechanical timer or an electronic one that can take the high start up voltage or you need to put the contacter between the cold light and timer.
Lot of pros pring with a music metronone and count.
Has anyone here found they have significant (+/- 3 seconds) lag with Gra-Lab digital timers? I have a 450 and an 850 (I think that's the number... its moderately fancy, above the 450, but not the fanciest one they make... offers times of up to 99 minutes, 99 seconds and 99 tenths, and a few other functions...). Both the 450 and the big brother have a pronounced delay between when I push the button/step on the footswitch and when the enlarger lamp actually kicks on. It isn't too big a deal as I usually print around 45-60 second base exposures, so if I add the extra 3 seconds onto the timer, and I don't get that much lag, it won't affect the final print. Still, it is quite annoying. Any other timers out there I should look at?