Yes, Line voltage switch (red) on back of the amp.
Mike
The 240V Option
Some high end amps can be switched over and run on 220 volts and I recommend it may sound better. The transformer primaries and the core seem to run slight more efficiently yielding lower impedance so the supply might appear slightly ‘stiffer’ to the amp’s audio circuits (always a good thing). Because the amp is now running at twice the voltage but half the amps (current) the wall wiring looks twice as thick to the amp as it does at 120 volt (ohms law). Now the amp makes even less audio noise on the line and it then rejects its own line noise better. The 220 volt outlet can be a standard 15 amp with 10 Ga.. Wire up to 80 feet then 8 gauge beyond that.
For the 220 volt lines, the electrician may, or may not know about a NEMA receptacle and plug number that is the same size and form as our common Edison duplex 120 volt receptacle but the wide blade of the plug is on the opposite side as the 120 volt duplex. Hubble or commercial Leviton works fine for 220 volt, and the 6-20 series looks less industrial in your home.
It is Nema plug number 6-20P. ‘Stay on line‘ is a good source but your electrician may like a local supplier.
BE SURE TO CHANGE OVER THE AMP INTERNALLY IF YOU DECIDE TO RUN 220 VOLT !
Last Trick – Twist the conductors
Lastly, you might ask him to twist the conductors one twist every 6-8 inches or so. Each line should be alternately twisted relative to the one next to it. This prevents any coherent coupling between them. Keep them away from each other by minimum 4 inches. It is perfectly OK to cross them at a right angle.
Final Word
If your electrician has any concerns about all this, be aware he is always concerned about CONTINUOUS current draw and rates everything and splits up the loads like the air conditioning and the electric dryer for the available amperage. Please explain to him that we are designing for incredibly short peak current pulses and we need the resistance back to the utility as low as possible for best amplifier performance. The continuous draw is negligible from an electrical standpoint. 10 gauge wire is the largest size that will fit into a wall outlet and as far as I know does not violate any codes but you and your electrician are responsible to be sure this is true in your state, county, and city.
Be sure that your speaker cable is at least 10 gauge. You should consider 8 or 9 gauge for speakers that are below 87db sensitivity, and/ or 4 ohms. Some manufacturers say, ‘our 14 gauge behaves like 10 gauge, etc.’, this could be true but I go for the real measured gauge.
Now, without exception over the last 12 years, comments from those that have done the above heavy gauge wire wall power mods say there is audible improvement in dynamics while making the sound even more detailed, yet much more relaxed with dark backgrounds leaving only the notes and music. I was very surprised the first time I did this house power mod. I did not expect the mid-range and the highs to clean up and get more coherent as much as they did. Of course bass and dynamics are better as you would expect with better current delivery.
link to page: https://www.msbtechnology.com/faq/house-power/
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