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Since the ACs are now running, I've notived the line voltage has dropped from around 120V to about 112V. I'm running my system off a single 20 amp dedicated circuit. Is there a cost effective way to maintain proper line voltage, or is this just something I'm going to live with during the summer months?
I could be wrong but I think your power company is required to provide 117-120 VAC. Most companies will come and install a voltage recorder if you ask and fix the problem if they know one exists. Course that's around here. YMMV I do know I wouldn't run my equipment at 112 volts without finding out what the lowest voltage it'll run on is.
Regarding tube equipment the problem is too much voltage. Most AC tube inputs were designed to run on 110v. 117/120 is bad for the equipment.
Mine goes up in the summer, rather than down. It typically runs at 122-24V, but will go as high as 127V in the summer. I think they boost the voltage to deal with so many AC's running. I think any tube stuff I go to build will have a PT that is 120V instead of 115V.
You would probably need to have that custom built; no?
I think the Hammond 300 series are for 117/120V. Anything above 120V I'm sure would have to be custom built. I wonder what effect that would have on an amp design if you didn't have enough play room with all the components? Say you have a PT wound for 125V and all of sudden your line voltage starts running the typical 120V.
With old tube gear 112 volts might sound mighty nice. I would give a hand full of Mullard EL34s for 112 instead of the 125 to 127 and more I see here way too often. It burns out light bulbs before their time too. First time I realized and measured the "problem" was years ago. I owned a conrad-johnson PV5 preamp and some times it sounded heavenly and sometimes awful. More than awful. The regulated power supply clamped at 125 volts and when the voltage went over that, I just had to turn things off. Not only does it raise the B+ in old tube gear but the filament voltage too. I've found a solution good for my voltage problems in the Hammond 300X universal power trannies. Sold at Angela and tubesandmore and ???. Make sure it's the universal Hammonds because the regular 300 series I bought last year were marked 115 volt, period. On the universal series, you can wire the input voltage for 100, 110 or 120 volts. I wired them for 120 replacing the original 117 (115?) volt in a pair of custom Dynaco MK III's I'm building myself. It's the center amp of the three different MK IIIs on the home page here... jim... http://groups.yahoo.com/group/dallasaudioclub/ Three Dyna MKIIIs