Amp and preamp on same outlet?

In the "old days" Preamps had switched outlets on the back where you would plug the amps into because the amps did not have a power switch. Some examples from ARC were the SP3A (still one of the best sounding Preamps I have ever heard) and the SP6 etc. So not only was the Amp and Preamp on the same circuit, but the amp was plugged into the Preamp, and I never thought that was detrimental to the sound. Of course that was back in the days before people were sold on $1,000 power cords and $5,000 speaker cables, etc.

Just an update for Jea48 and others(?) following the Krell amp rear breaker panel value saga here. :^)

To backtrack, I tried to be of service to the thread as a messenger. I posted info from an email from Patrick of Krell advising that the breaker panel value on the back of these amps is 50 amps. I was however curious so I contacted Dan D'Agostino. He advised the breaker value for 120v service amps is 20 amps for reasons noted below. Fwiw I use a custom made 20 amp power cord, with the 20 amp dedicated circuit on my Krell amp.

I can therefore only recommend that any Krell amp owner with questions, clarify directly with Krell for their specific amp if they are curious. Patrick is a great resource for me, and I would find it awkward (as you can imagine) to approach him about Dan's info. It won't change my personal situation.
The emails follow

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Patrick Bresnahan 09/03/2015
To:
PBresnahan@krellonline.com

These are 50 amp breakers.

Sent: Friday, March 06, 2015 2:36 PM
To: Patrick Bresnahan
Subject: RE: breaker value on back of amp ?

what is the breaker value on the back of my fpb600 or the other high power amps. FPB-700cx ?
the Krell stock cord looks like a 15 amp ? and my wall is 20 amp service.
is the breaker 15 amp ?

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I asked the same question to Dan D'Agostino

From: dan@dandagostino.com

Date: Tue, 10 Mar 2015 17:14:28 -0700
You have very little protection if there was a failure with a 50 amp breaker. If the unit is set for 120 volts the most a standard 120 volt receptacle can safely have is 20 amps.
There is no reason for a 50 amp breaker. It is not safe
Dan


From: dan@dandagostino.com

Date: Tue, 10 Mar 2015 16:27:03 -0700
Hello Chris that amplifier should Have a 20 amp breaker not a 50

J_stereo, I had a ARC SP3 along with a Dual 51 and Dual 75. I never even thought of using the switched or unswitched outlets on the back. I don't remember doing any experiments to discourage using them, but perhaps others advised against doing so.

But I certainly do remember little concern about power cords, vibrations, EMI or RFI much less ics and speaker wires. My first special speaker wires were from Bob Fulton and I realized that I had used identical wires on my welding rig while in undergraduate days in a material testing lab.

Jea48

:^)

Electricity scares the hell out of me so I was compelled to post the info.
There is no foolery with Electricity. It needs to be done the right way. But ironically the result of this hobby, the music itself, is all about fooling ourselves ?

btw - I enjoyed your electricity video especially the power plants. Thinking about it now I find it kind of funny that the closest I came to feeling like I owned my own standlone powerplant, was with these
OTL's
The speakers could be disconnected and others reconnected at any time without powering off the monoblocks.
They used horizontal sweep tubes. 600 watts at idle just like a 50 inch plasma tv according to the manufacturer.
No TV in this room so I kind of justified things in my mind.

Almost felt like the speakers were connected directly into the wall outlets. In memory now, I no longer own them, they were like driving a 911 but you could only use first gear. They were designed around the needs of Acoustats. Issues developed with consistency and reliability.

Cheers