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Do I need a 20 amp or 15 amp power conditioner/surge protector

I have a Dan D'Agostino Progression Stereo amp that has a 3,000 VA power supply transformer coupled to 400,000 microfarads of power supply storage capacitance.  It's a true triple down amp rated at 300 Watts into 8 Ohms, 600 Watts into 4 Ohms, and 1200 watts into 2 Ohms. I'm using a pair of Magnepan 3.7i's which are rated at 4 Ohms. 

One of the odd things is that the amp comes with 20 amp power cord that has a 20-amp IEC connector at the amplifier end and a three-conductor 15 amp AC plug at the other end. The instruction manual tells you to plug it into a 15 amp wall receptacle. 

After a recent scare, I decided I should get some protection as well as clean up the AC being fed to my components. My LAD explained to me that the minimum I should get is the Niagara 5000 because it's rate for 20 amps, but when I asked why does my amp need that when it's plugged into a 15 amp receptacle, he said that at high loads, the amp may be pulling a little more than 15 amps and power conditioner rated at 15 amps would restrict that and the audio quality would suffer. 

So, here I am trying to figure this out, I mean, my LAD may have point since the amp manufacturer supplies a 20 amp cord, but tells you to plug it into a 15 amp receptacle, but I just don't know. For the price point I'm looking at, I've narrowed it down to either the Furman ELITE20 (20 amp) or AudioQuest Niagara 1200 (15 amp). Do I really need a power conditioner rated at 20 amps, or will one rated at 15 amps be fine? Also, is it really possible under heavy load my amp could actually pull more than 15 amps out of a 15 amp receptacle? Very confusing... Thanks for any clarity you can provide. -cheers!

 

 

128x128jimmy_jet

Showing 4 responses by jea48

jea48
4,323 posts
 

@jimmy_jet

3,000 VA power supply transformer coupled to 400,000 microfarads of power supply storage capacitance.

3000 VA / 120V = 25 amps...

 

Are AC line-treatment devices necessary? Define necessary. "We try to build equipment that puts up with dirty AC lines," Pass told me. "Our customers expect it, and if they have a problem, we hear about it. We don’t design around the assumption that there is AC line conditioning in the system. That said, if the line conditioning has adequate current capacity, we expect some benefit."

That’s a big "if," since some types of line conditioner can choke off current and squash dynamics.

Power According to Pass | Stereophile.com

 

Bigger is better...

 

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jea48
4,323 posts
 

 

jea48
4,323 posts
 

@jimmy_jet said:

I see what you’re saying and was thinking the same thing, it logically isn’t adding up, especially when the Dan’s manual says "plug into a 15 amp receptacle", yet, they provide a 12 gauge 20 amp cord with a 15 amp male plug for the wall end...?

 

How many Dan D’Agostino Progression Stereo amps would Dan sell if the cord had a 20 amp male plug? Most of the wall outlets in our homes are 15 amp. (In wall branch circuit wiring is 14 gauge copper connected to a 15 amp breaker.) Good thing Dan spent the money for a soft start circuit on the amp.

(Note: Two or more 15 amp receptacles can be installed on a 20 amp branch circuit per electrical code. A duplex is two.receptacles)

The amp probably sounds ’fine’ on a 15 amp circuit fed with #14 gauge copper wire. It more than likely would sound even better on a 15 amp dedicated circuit fed using #12 copper wire. Or even a 15 amp dedicated circuit fed using #10 solid copper wire.

The wall outlet could still be a 15 amp duplex receptacle outlet per electrical code. If you wanted to use a 20 amp duplex receptacle outlet then the circuit breaker would need to be a 20 amp to meet electrical code. You can still use the same power cord with the 15 amp male plug. The only difference between the 15A and 20A plug is the neutral blade on the 20 amp plug is turned 90 degrees with repect to the Hot blade...

FWIW a 15 amp circuit breaker will pass short quick current draws of 30 amps all day long without the breaker tripping. It will handle a continuous connected load of 15 amps without tripping.

 

Pass said:

"choke off current and squash dynamics."

It’s not a continuous draw of current Pass is talking about. 14 gauge wire is more than big enough for the continuous current draw of Dan’s amplifier. Using a bigger wire gauge is for dynamics.

3,000 VA power supply transformer

Fed with #14 gauge copper wire...

Any other loads on the 15 amp circuit? Any idea the total length of the #14 gauge branch circuit wiring from the electrical panel to the wall outlet the amp is plugged into? The length of the wiring can make a difference too.

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jea48
4,323 posts
 

@jimmy_jet

I think you missed the point I was trying to make. JMHO, a 15A branch circuit, which I assume is a convenience outlet branch circuit consisting of 14 gauge copper wire, is not doing the Dan D’Agostino Progression Stereo amp justice.

If it were me I would have a 20 amp dedicated branch circuit installed. Circuit minimum wire size for a 20 amp circuit is #12awg copper. If it were me I would pay the extra cost and have #10awg solid copper installed.

Type of branch circuit wiring to have installed?

Read pages 16 thru 36.

An Overview of Audio System Grounding and Interfacing

 

Jim

 

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