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AC Power Between Amp and Preamp

For as long as I've had my ARC D-90 amp and SP-12 pre-amp I have connected the amp's AC Power Cord to the Switched AC outlet on the Pre-amp. I actually connect a decent quality surge protected power strip to the switched pre-amp outlet and plug the amp, subwoofer and cooling fan to the multi-outlet power strip so everything powers up and down together.

I have not noticed any issues at all with this set-up and have been doing it for years. I did read in another A/V Receiver manuel however where they cautioned against plugging high current components into the back of their (Pioneer) receiver/amp type unit.

Needless to say the D-90 amp pulls a lot of current. The Bob Carver Sub supposedly has an 1100 watt internal amp, so the big question is should I be running these high current components through the pre-amp. Otherwise I'll have to come up with another way for easy on/off for the amp and sub.

Thanks for any comments.
jamesk58
electroid
283 posts
 
I had a CJ preamp with outlets, one switched the others always on. Not only did equipment sound better when it was not plugged into it but the preamp sounded better when those outlets were disconnected internally.

ET
jamesk58 OP
73 posts
 
I did switch the power set-up to bypass the pre-amp and actually got a hum! Switched it back and was fine.

I'd be very surprised if there would be a noticable increase in sound quality by powering the amp differently. I am more concerned about too much voltage running through the Pre.

I did in fact dig out the SP-12 Pre-amp manual I've had since 1985 and it does specifically refer to plugging the amp into the switched outlet on the back of the Pre-amp.

The SP-12 has two power switches. The instructions state to use the 1st switch on the Pre to power just the Pre, wait a minute for it to warm and then press the second power button which then activates the switched outlet on the back and allows the amp to power-up.

Of course after all these years I hardly wait a minute between depressing the two switches and click the second switch right after the first.

As I said, I haven't run into any issues and very pleased with the sound so I guess it works fine as is. Maybe I'll be more diligent in letting the Pre warm a bit before powering the amp.
ozzy's avatar
ozzy
7,564 posts
 
All in all, (depending upon your equipment and the Amps they draw) in most instances you would be much better off plugging your Amp into a seperate outlet instead of into the Preamp.
Pardon the question, but I have to ask, how hard is it to turn on 2 devices instead of one ?
eldartford
4,262 posts
 
I have an old and inexpensive Adcom ACE-515 AC Enhancer. It isn't anything fancy, and Adcom now sells an improved model. However, it does claim to do some filtering and spike/surge protection, but for me the best feature is that it properly sequences power up and power down of the source components and the power amps.
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