Doug, how is the fan on the Delta 3? I haven’t tried the River 2 but folks here don’t seem to notice the fan being a problem. My Delta Pro fan can be obnoxious but not as noticeable for steady loud music. I seem to be more sensitive than others to these kinds of things too.

Just so that everyone understands their options with how these can be used, my unit stays plugged in to the wall 24/7. The performance is exactly the same plugged in vs unplugged.

Even plugged in to the wall, the components are still powered by the EcoFlow battery. The only time noise is introduced is if the internal charge starts during stereo use. In the event that this happens, there is a buzz that occurs. If this happens to me during play, I go into the app and jump the recharge limit level down.

And I have yet to ever hear a fan come on with mine.

I looked into this technology a couple of years ago as I was thinking about using a Tesla Powerwall to power my system.
At that time (say 5 years ago) I was warned that the inverters were the weak point as they didn't produce good enough sine waves.
Has there been a big upgrade in this technology?

In reading the problems that people are having with DC offset and such just gets me wondering if the systems aren't fully where they need to be yet?

Yes. The older inverters used Modified Sine Waves, which damaged sensitive electronics, motors and compressors would hum, overheat, and fail prematurely, etc. That's why these new inverters advertise that they produce Pure Sine Waves.

My experience so far with the Delta Pro Ultra (DPU)

Initial setup:
Wall -> Torus AVR 15 -> x2 power distribution boxes -> components.

New setup:
Wall -> DPU -> Torus AVR 15 -> x2 power distribution boxes -> components.

Turned everything on and sat down to listen… and was very disappointed. Sound stage was pushed into my face; I did have a nice bit of envelopingness; however, the dynamics were just gone. I let the system play for a few hours. When I came back, it was about the same.

From the Torus I had  2 PCs feeding two power distributors. The other outlets from the Torus had parallel plug in devices: Verafi Snubway, Puron, ADD-Powr ElectraClear EAU4, RS Audio CF-1 and MF-1.

Removed these, and the sound did get a bit better, nothing significant.

The next day, I removed the Torus from the setup. So both power distributors are connected directly to the inverter.

Newest setup: DPU -> 2x Power Distributors -> Components

After this switch, it sounded so much better. Dynamics returned the inner details, especially the atmospheric sense of space.

The micro and macro details are just insane now. The thing I keep coming back to is the sense of space the music is happening in. All the subtle details and nuance are there. I’m really thrilled with the results.

I think there was a bit of a burn-in or settling period for the inverter. Second and third days sounded much better. I think it works similarly to a class-D amp.

10 years ago, when I looked into solar, inverter power quality wasn’t great.

Hooked up to the oscilloscope. There was a chopped waveform from the wall and an almost perfect waveform under load from the DPU.

Based on what I’m hearing, the DPU has cleaner / better power than the wall.

DPU has kept the power steady at just under 121v. Over one minute, micro fluctuations from 120.81v to 120.9v.

Outlet: 123.78v to 124.23v over 1 minute. And this voltage is constantly drifting on a macro scale throughout the day.

I read 0.00v DC from the DPU.

I can power the entire system for 10 hours or more.

I’m just waiting on the solar panels to make my stereo 100% solar powered. There is a guy about an hour away that buys panels by the truckload. Just waiting for him to get some that work for me.

The AVR has a high idle draw ~150w. That will drain 50% of the 6kWh battery in 24 hours.

Always on load without the AVR ~78w.

Always on load with AVR + components ~210w.

I'm not motivated to try the AVR after the DPU.

I ordered a 8 socket distributor that I can try combinations of the parallel filters. Right now RS Audio CF-1 and MF-1 are being used, I enjoy what they bring.

HK, The #1 reason for the BIG one is to get enough PV power. I could have gone with the Delta Pro 3 as that might have worked, with only 2600w PV input, I was concerned I wouldn't have quite enough in winter. DPU is 5600w from PV and if need be I can use it as a redundancy for the main house.

Yes, always something to mess with. My issue is even when it's sounding incredible I want to know how much better can it get! This month have a pair of Thoress 845 monoblocks arriving so more power draw and more things to mess with... It never ends.

The DPU has two different outputs for 120v. 2 of the outlets are passthrough (UPS) meaning that the AC from the wall passes through. If the power goes out in less than 20ms it will switch to inverter. The other 2 are always inverter powered.

It seems the passthrough outlets are filtered.

If I didn't mention it I do have the chassis ground going into the house ground.

Lon, I chose that model for the same reason, 4 3 prong outlets. Amp into one, preamp into one, sub into one and a diy “strip” into the last with DAC, DDC, Mac Mini and Snubway. The Snubway is there due to the crap switching power supply in the Mini. No issues at all.

I know you’ve got other power goodies, it would be interesting to see how a $200-300 EcoFlow compared. I bought one new and another refurbed. The refurb works fine and minus a mark or two on it that I really had to search for, the refurb is a great deal.