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Dumb Question 36

I just bought a used Conrad Johnson PF-R pre-amp and noticed that it has no power on/off button. Am I supposed to leave the unit on all the time? Is this a common practice in audio quipment these days? This is the first unit I have ever seen with no power switch. I have heard that there is a certain protocal you should use when turning on your system and reverse the procedure when turning it off(something like turn pre-amp on first then power amp and then reverse the procdure to shut down). I presently have the amp and pre-amp plugged into the same surge protector. When I turn on the power button of the surge protector naturally both units come on--no problems--but when I turn off the power through the surge protector I get a LOUD "POP" from the speakers. This can't be right so how do I hook up the sytem to the power correctly?

Thanks.

Steve
say811
sugarbrie
3,854 posts
 
Yes, Yes, leave the preamp on all the time. It was designed that way on purpose. It would take a few hours for the FETs (Field Effect Transistors) to get up to speed if you shut it off. By the time the preamp warmed up fully, you would be done listening. It uses a tiny amount of power, so don't worry about your electric bill. None of the Conrad Johnson/Sonograph/Motif preamps have on/off switches.


You should not shut off everything at once by way of the surge protector. The general rule is amplifier on last and off first, for the very reason you state (loud pop). Since the amp is still on, it amplifies the shutting off of your other gear. Could cause problems eventually.


Some AC power conditioners/surge protectors (Adcom and Rotel come to mind), have circuits that automatically turn the equipment on and off in the proper order when you hit the power switch on the AC power unit.

winoguy17
1,195 posts
 
I would try to not have both power and pre plugged into the same surge protector, Plug amp right into the wall if you have to, also, turn off amp first as suggestewd by Sugarbrie
driver's avatar
driver
750 posts
 
What Sugarbrie said. I have a pre amp (Pass) with the same setup. No power switch. My amp also has a standby switch so all I do is use that & my system is ready to go.

I also don't use a conditioner but suggest you try plugging the preamp directly in the wall. You might want to experiment with plugging the amp directly in also to see if the power conditioner affects the sound.
glen's avatar
glen
714 posts
 
I leave my power conditioner on 24/7. I use to own a Classe pre-amp that ran 24/7. (no off switch) This is normal on some pieces, as they require forever to warm up.

I would recommend adding a couple dedicated circuits. Then run the amp directly into the wall. Dedicated power is usually plenty clean for an amp and better sonically IMO.
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