HI. Is there any way I can get rid of that loud POP sound though my speakers that I get when I turn off the preamp (and leave the amp on)? My preamp is a C-J PV10A, which is recommended to turn off when not in use, but my amp is the C-J MF-2200, which is SS and can be left on. That sound can't be good for the speakers.
on my system i turn off the power amp first and that stops the pop from making it to your speakers,you can allways turn your power amp back on after you turn off your preamp,,
Okay, thanks! I was following C-J's manual and it said I could leave the amp on 24/7, but that I should turn off the preamp when not in use, which extends the life of the tubes. Guess that isn't a good idea in this case! After the first time it happened, I started turning the amp off first, but thought there was something I was missing (I don't have a mute button, and the volume control does nothing in this case).
I've had three CJ based pre-amp/amp systems and always turned off amp first (they were all tube designs) and waited about 1-2 min then turned off pre. If you turn off pre but leave amp on you're allowing some voltage to leak into speakers which causes popping sound - not a good thing.
When you shutdown your preamp - it's circuitry goes through a "shutdown transient". That is as it loses power, the circuitry goes through a type of "death throw".
Some amps and preamps have a "muting circuit" to disconnect the output before the transient. Yours evidently doesn't have that circuit.
You should always power up your equipment in the direction of signal flow - source components on first, then preamp, then finaly power amp.
When you shutdown your system - the order is reversed - the power amps should be shutdown first. So if you follow the proper shutdown order - the power amps should already be shutdown when you turn off the preamp - so the shutdown transient won't damage the speakers.
Note - the power down transient of the preamp may not be suppressed by the volume control - depends on the preamp design. So you can't depend on a volume control to save your speakers.
As Paul suggests, learn / practice proper startup / shutdown proceedures before you damage your speakers.
When C-J wrote your manuals, perhaps they were assuming that your C-J tube preamp would be paired with a tube power amp, and that your SS power amp would be paired with a SS preamp.
That way, your tube power amp would be powered down [ to extend tube life ], when you powered down your tube preamp.
In the latter case, your SS power amp would remain on with the SS preamp.
Mixing tube and solid state components can be problematical, depending on the design - although the marriage of the two technologies can have a positive effect - exploiting the advantages of both.
For example, tube preamps will usually have a greater amount of DC voltage on their outputs. That's OK with tube power amps which are capacitively coupled. However, many transistor power amps are "direct coupled" - no coupling capacitors in the signal path - thus expecting a very low DC component from the upstream SS preamp.
If the upstream preamp is tubed, and the power amp is a "direct coupled" SS - there can be problems - which can easily be remedied by installing coupling capacitors.
Moral to the story - you just have to be aware of the various characteristics of the components you link together, for proper "care and feeding" of your stereo components.
Amplifiers amplify! Why would you want your amp to strengthen the sound of the power supply of your preamp collapsing? Next you will be telling us that you cannot pick up your lawnmover with it running and not cut off your fingers.
To Jea48, that won't do any good because the turn-off (and -on, too) transient is created by the line stage, and that's always in the circuit full volume no matter where the selector switch or volume control is set.
"Next you will be telling us that you cannot pick up your lawnmover with it running and not cut off your fingers." Just who is 'you', Thg? There are a dozen people above you. .
The input impedance to an amp is quite high. Therefore, it doesn't take much signal for the amp to see it.
If you install a shunt - or even if you try to short the output - that shunt or short is still in parallel with the amplifier input. [ Any "short" you place on the terminals still has a finite resistance - so it's not a true short. ]
Even though most of the "signal" current from the shutdown transient is sent through the shunt - a tiny amount still finds its way to ground through the amps input stage.
Result - problem not solved.
The only safe solution here is to shutdown the amp.
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