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?


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.

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
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.
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.
leave the amp on the surge protector unless it sounds better direct to line. It will "pop" no matter what you plug it into if the correct 'last on, first off' sequance is not followed. But I would always leave it on; sounds better that way.
If you have not been leaving your equipment on for days at a time, then you are in for a treat.
steve you've made a slight mistake here. this is dumb question 43. :o) actually, as others have said repeatedly, repeatedly, repeatedly: ain't really no such thing as a dumb question, only a dumb cousin. but then, if you marry your dumb cousin......

Omit the surge protector. Odds are better than even that it's compromising the sound...especially on front end components like CDP or pre....
Check this link. The "POP" is because you're getting a "discharge" (most likely a discharge to ground) since you are in effect turning every component on AT ONCE, when you turn on your surge suppressor.


In the above link, I paraphrase one method of a preferred "turn on" and "Turn off" sequence. There are other ways to do it, obviously. Naturally, if you're going to use a surge suppressor or power conditioner, it should be turned on FIRST. Imagine if the unit was not in the circuit and everything was plugged into the wall (AC mains). You wouldn't plug everything in, then run down to your breaker or fuse box, then TURN ON the power from there, would you? I didn't think so!

1.) If you're going to use a power strip, or a power conditioner, plug it into AC mains (wall outlet), and turn it ON.

2.) Then start following the directions from the following link:


2a.) Connect you interconnects.
2b.) Connect PREAMP to AC Mains and TURN ON.
2c.) Connect SOURCE(s) to AC Mains and TUNR ON.
Now, if your preamp or sources were going to discharge themselves to ground and give you speakers a POPPING noise, you're protected, since your POWER AMP is still OFF.
2d.) Connect POWER AMP to AC Mains and TURN ON.

Generally if you speakers 'POP' at this point, it's most likely an issue isloated to your power amp. You would try disconnecting the interconnects from your preamp to power amp, then try powering up the power amp. If youy get the pop, then, it's your amp. Though I'm going to bet money the POP is coming from the discharge to ground while your preamp powers up.

For this reason, it is generally recommended to turn the amp on LAST, and shut it off FIRST. That way your speakers are protected. I'm basically echoing what Sugarbrie said.