HiFi quality sine wave inverter

[Number 6]

I'm in the initial stages of planing a separate off grid solar system for my HiFi equipment and DC lighting. Possibly the fridge and TV as well. This is due the the fact that where I am in the process of building here in Mexico the grid power is dirty and goes out all the time. I've already identified the streamer and DAC I will use powered by batteries. The problem is the power amps, which draw a lot more current. Does anyone know of a "clean" inverter? If you are familiar with high end audio, you might know about power conditioners. Basically half of one is an inverter. All input appreciated.

[MichaelK!]

It will help if you can get some numbers in regards to what you are talking about. I'm assuming your power amp is a 120V unit. BTW, mine is a Carver. I used to have a Phase Linear that died and couldn't be repaired. You can use what's called a "clamp meter" that can measure amperage. I have this one.

https://www.ebay.com/itm/UNI-T-UT216C-600A-Digital-Clamp-Meters-NCV-LCD-Test-ACDC-Auto-Range-Multimets/333683530820?epid=710119969&hash=item4db1169c44:g:wfEAAOSwiKpfM1PL

I'll assume though that the unit wouldn't consume more than 15A at 120V, because it has to be designed to operate off of a standard 15A house socket. Even a toaster oven consumes only 12-13A, so I'm sure the amplifier is significantly less.

But to better answer your question, any Tier-1 product with the label Outback, Magnum, or Schneider should work for you. I can tell you that my XW+6848 produces cleaner power than my generator, which is supposed to be sine-wave. When powering my 240VAC well-pump on the generator, it consumes about 10.1A of power and pumps 275 gallons of water per hour. Running the same pump on the inverter, I see it consumes 9.4A of power and pumps 305 gallons per hour. It's running better because the inverter power is cleaner.

https://ressupply.com/inverters/schneider-electric-conext-xw6848-na-invertercharger

Unless you are powering big-ticket items like a well-pump, you are not likely to need such a big unit. Schneider makes a lesser capacity 24V that I also have, that has worked flawlessly for me. I haven't run wifi equipment off it, but it powers all my power tools without complaint.

https://ressupply.com/inverters/schneider-electric-conext-sw4024-120240-invertercharger

[Mike90250]

Look for the THD spec for an inverters output. Most major brand pure sine inverters meet or exceed power company Power Line specs.

[Number 6]

I'm a tube guy. A McIntosh 225 (25w per channel) I have measured with a Kill-A-Watt at 81amps and 90watts. Interestingly my large refrigerator measures 79a and 93.3w
I was hoping to get by with something a lot less expensive.
I have a clamp amp meter coming. Should I expect a different reading with that?

[Mike90250]

.....I have a clamp amp meter coming. Should I expect a different reading with that?

You need a PEAK HOLD meter, the kill-a-watt is only an average reading, the fridge motor startup, expect 10x the running amps, and that in VoltAmps, not simple watts

[bob-n]

If you're planning to run both a fridge and audio from the same power line, you may be fooling yourself by getting ultra-pure input power. The fridge (or any other motor load) will put more noise on the line than you can imagine, no matter how good the inverter outputp was.

[J.P.M.]

I'm a tube guy. A McIntosh 225 (25w per channel) I have measured with a Kill-A-Watt at 81amps and 90watts. Interestingly my large refrigerator measures 79a and 93.3w
I was hoping to get by with something a lot less expensive.
I have a clamp amp meter coming. Should I expect a different reading with that?

You sure about those current numbers ?

As for power ratings on audio stuff, like most high end audio back in the day, Mac's were always conservatively rated. I wasn't a big tube aficionado, but as I recall back in the day I cracked a few windows with a pair of Crown D150's that I had dyno'd/bench tested @ ~ 125 W/channel and 8 Ohms nominal impedance. As you probably know,, they were spec'd @ 75 W/side @ 8 Ohms but never ran them off anything but stable grid power.

[bob-n]

Seems like they just left out the decimal point (81amps = 0.81 amps, 79a = 0.79 amps). With that, the current and power levels agree and make sense for the units being measured.

As to the exact power level for the fridge, it would vary depending on whether the compressor is running or not. The KillOWatt is capable of long-term averaging but most people just use it for immediate average measurement.

[foo1bar]

The problem is the power amps, which draw a lot more current. Does anyone know of a "clean" inverter?

What does the power amp use for power?
Is it already taking the 120V power input and changing it to a DC supply for it's internal use? (I'd expect it is)
If it is, I'd look at running it off DC - using a DC voltage converter to get the voltage needed.

Also - I would agree that a fridge is going to introduce noise to the system - I'd want that separated from the audio supply as much as possible - a different inverter or something. If your closest common point is at the batteries, the batteries are going to be fairly stable/low-noise, even with a largish changes in power draw.

[J.P.M.]

Seems like they just left out the decimal point (81amps = 0.81 amps, 79a = 0.79 amps). With that, the current and power levels agree and make sense for the units being measured.

Kind of what I figured, sort of pointing out the obvious.

[Number 6]

nThanks guys for the input. That's a really good point about the noise of the fridge. I should have thought of that. Foran AC system I'd have a separate 20a circuit just for the stereo. I most certainly read or wrote down the Kill A Watt readings incorrectly, but when your down on you hands and knees with no backlight...
I've thought about battery power for the power amp(s) as well and will most probably need to go with the Class D rather than tubes. I need to investigate this more. I'm pretty sure like TVs they use more than a single voltage.

[Number 6]

foo!bar, I hadn't thought about 2 separate inverters. One connected to the refrigerator would act as a noice filter, so the other inverted could provide a clean sin wave for the audio equipment, correct? I just double checked the plate voltages of my tube amps. One is 390v and the other 2 mono blocks are 466v. Sort of like trying to charge an EV without an inverter.
MichaelK!, The inverters you sent URLs for are very nice and very expensive. Most people I know have a voltage regulator between the grid power ant their fridge. It would be cheaper to buy a new fridge if it blows up than 2 inverters. Once I get the clamp meter I'll check the startup amps.
The reading I got for the tube power amp using the Kill-o-Watt for 24 hours was 4.3kWh, but that was without playing any music. Any suggestions on a lower cost inverter will be appreciated.