Electrical Power - Dedicated Runs

[JoeN]

We are considering purchasing some MTRX2 monos. They each need a 30A dedicated circuit. MSB states the following:

MSB’s recommended wiring

◦ 1 to 40 feet: 10 gauge wire
◦ 40 to 60 feet: 8 gauge wire
◦ Over 60 feet: 6 gauge wire

The 8 gauge (or 6 gauge) requires a jump-down back to 10 gauge using a junction box, somewhere just before the outlet because the largest wire that will fit in an outlet is 10 gauge. Install one dedicated line for all front end equipment, and one for each amplifier. If you must feed old branch circuits off one of these outlets, it is not absolutely necessary that your audio lines are dedicated lines as long as the wire path at the outlet you are using goes directly back to the breaker panel using 10 gauge or heavier wire. The circuit can branch to other outlets from your audio outlet if necessary. (some people won’t agree with this).
Click to expand...

Has anyone else here run 6 gauge wire stepped down to 10 gauge wire? If so, how is it’s performance?

Vince Galbo’s article: How to Wire your House for Good Power?

https://www.msbtechnology.com/faq/house-power/

[cleeds]

Originally Posted by JoeN

We are considering purchasing some MTRX2 monos. They each need a 30A dedicated circuit...

It looks like these amplifiers use a back panel 30A rated connector, but it's not likely that the manufacturer is really recommending a 30A line for each amp, especially at 240VAC. The recommendation for de-rated lines is always a good one, especially to help prevent voltage drop, but it's most likely that they can be connected to a conventional 20A (I'm assuming US voltages here) breaker.

Using the 30A connector is consistent with the de-rated line recommendation.

You might also want to consider that if you feed branch circuits off of this de-rated line spur, you will not be able to safely use any panel breaker that exceeds the capacity of those branch lines. So that may leave you with a 15A circuit.

IMO, nothing beats proper, dedicated lines as a starting point for AC power. I think your next step is to clarify the manufacturer's recommendation. The $1 million question: How much does each amplifier draw at rated power output? I don't see that listed in the online specs.

[tdelahanty]

Plus 1 to Cleeds. How often will you run the amps at their max rated power? Under normal listening conditions they will use very little current.

[JoeN]

Thanks guys. That’s very helpful.

I already have 3 dedicated 20 A lines run. That’s what they are currently plugged into.

It was suggested to me to go down to 6 gauge wire for most of the run and then tie into the 10 gauge wire that I already have run. The electrician will be here tomorrow so I’m trying to figure out what needs to be run. It’s only an estimate, but …

[cleeds]

Originally Posted by JoeN

... I already have 3 dedicated 20 A lines run. That’s what they are currently plugged into.

It was suggested to me to go down to 6 gauge wire for most of the run and then tie into the 10 gauge wire that I already have run ...

Frankly I think you are in fine shape right now, power wise. 10AWG should be a-ok, unless m-a-y-b-e you have a really, really long run from panel to outlet. Maybe.

[JoeN]

Thanks again. I have about a 50-60 ft run.