The Xmas Question: Audio Quality of PV Inverters

[JoachimStrobel]

As many others I have a PV system on the roof. The inverters are slaved to the grid phase (the law here and I guess elsewhere). On a sunny day I produce more than I need.
There have always been stories that the AC quality imprints on an amp’s audio quality. In times where routers and network cables are getting audiophile branding, the question of AC power may deserve a (Xmas) thread.
How close do my inverters follow the grid lead? Are there tolerances and will my amp notice them? Is that different when some of the grid power is still used or when I am 100% self as supplied and even inject power into the grid?
I have a battery that will produce AC at night, still synced to the grid. Would that be even “purer” power?
It gets even better. I have an isolation switch that allows one of my inverters to produce AC when the grid is dead. In that case, my AC quality only depends on my own inverter. I was thinking auf AB tests but it is a bit a huge effort to kill the grid power and jump to island mode. I could run that island inverter by PV (300V) on a sunny day or by battery (50v). Would that make a change? I could probably tap into the battery’s DC bus and attach an audiophile DCAC inverter. The battery is charged via a DCDC converter from the PV. I could probably revert that and drive my amps somehow with DC (it seems that there is already a thread for that).
It seems that the possibilities are endless and I might drop everything else and start exploring. Should I take out patents and market stuff?

 

[staticV3]

You're wasting your time. AC quality does not affect your audio equipment in the slightest.
https://www.audiosciencereview.com/...ac-distortion-noise-on-audio-equipment.25501/

Edit: Amir has tested lots of AC equipment by now. The result is always the same. These filters and regenerators and fancy cables do absolutely nothing to the output of your gear. They're useless.

Search results for query: Ac

www.audiosciencereview.com

 

[Mnyb]

Yeah waste of time and that’s not really how things works , the grid is “very strong” compared to the PV it has no choice but to keep to the grid frequency.
I never noticed a thing when I got my solar array and PV inverter .

Island mode my gues is that it’s actually worse then but unnoticeable anyway , in Island mode your power source comes from a higher impedance and is thus phrone to sag more and voltage waveform can be influenced by the current draw of your gear .

 

[FrantzM]

I am 80% on Inverter , I also have generators (plural) and commercial AC. No difference in sound. Differences in comfort however. For now my inverter and solar array cannot yet run my Air Conditioners . This will be remedied this coming year.

Advice:
Don't bother. Complete waste of time and resources. The only advantage of running the gears from DC, could be some in efficiency.... but nothing in sound quality. The gains in efficiency is not a given by the way. You may have to perform in most cases DC to DC conversion and these would incur their own efficiency losses... , One could retort that some of these efficiency could be better than the actual AC to DC conversion of usual power supplies but.. again , it depends , on their design and the load and the voltage conversion and those devices designs and ... ... .... Don't bother, not worth the time and effort, if this is/are sonic (or efficiency ?) gains you're after...

Peace

 

[Mnyb]

Yeh don’t bother btw better unsub to tread before it becomes a mess cheers....

 

[JoachimStrobel]

Ok, I see, there is no market for audiophile inverters. Not even an audiophile benefit for listening in bright sun light or at night. Even wiring my house with a DC line will not help the DAC.
I could try and use PV energy to de-humidify the rooms’ air and therefore reducing sonic absorption.

 

[lisgotan]

Ok, I see, there is no market for audiophile inverters. Not even an audiophile benefit for listening in bright sun light or at night. Even wiring my house with a DC line will not help the DAC.
I could try and use PV energy to de-humidify the rooms’ air and therefore reducing sonic absorption.

Inverters isn't going to do anything. You need to rember that your PV is slaved to the grid, so whatever "magic" the inverter has, it's gone.

And then, unless you are living in some industrial area, residential places are quite clean in terms or power. Any noise is usually from home appliances connected to the grid. They may be a little annoying at times (eg. Turning on/off light switches may produce a pop sound).

AC filter can reduce noise floor of your audio gear but it's not tremendous.

 

[staticV3]

AC filter can reduce noise floor of your audio gear but it's not tremendous.

Any examples with measurements?

 

[JoachimStrobel]

My point is, that in an Island-type PV system, the inverters produce without an external grid. They hence could generate the perfect sine wave or whatever. Mine does that only on one phase, but that is enough for a sound system.

 

[staticV3]

They hence could generate the perfect sine wave or whatever. Mine does that only on one phase, but that is enough for a sound system.

it doesn't matter how perfect the sine wave is.
your inverter could be outputting this tragedy:

and your audio equipment still wouldn't care. The output would be the same as with a perfect AC sine wave. See here.

 

[Sokel]

Any examples with measurements?

I have some but it's about noisy devices (like led strips,light attenuators,etc) on the same grid.
At those cases a furman I tested seemed to lower noise floor of the measurements.Nothing audible of course.
I think that is the way to test them,where the problems are,if normal they appear to do nothing.

 

[JoachimStrobel]

it doesn't matter how perfect the sine wave is.
your inverter could be outputting this tragedy:
View attachment 250785
and your audio equipment still wouldn't care. The output would be the same as with a perfect AC sine wave. See here.

Is this a real measurement of an PV inverters’s output?

 

[Palladium]

Is this a real measurement of an PV inverters’s output?

If your inverter is the pure sine wave type, that's gonna be much, much worse.

 

[staticV3]

Is this a real measurement of an PV inverters’s output?

See here.

 

[JoachimStrobel]

See here.

Good read thanks. I hope at least some people understood that no total seriousness is intended by this thread.
Nevertheless the point is, as Amir commented too, that is has to be seen if AC quality makes a difference for driving 1Kw Class A amps which is hard with traditional AC cleaners or even an UPS. I have not read trough all the 42 pages of the linked post. May be it is answered there somewhere.

 

[lisgotan]

it doesn't matter how perfect the sine wave is.
your inverter could be outputting this tragedy:
View attachment 250785
and your audio equipment still wouldn't care. The output would be the same as with a perfect AC sine wave. See here.

Don't be so fast to say your audio equipment wouldn't care..

Amirm did the test using a Topping A90 which is using 2 x all-in-one power module (IRM-20-15).

https://www.farnell.com/datasheets/3154728.pdf

So, what his tests did is to show that the filters built-into the power module is working....

 

[Palladium]

You gonna try harder at baiting ASR into justifying poorly engineered trash.

 

[dlaloum]

If your inverter is the pure sine wave type, that's gonna be much, much worse.

All PV inverters are required to be pure sine wave... I think the Grid requires no more than 3% THD - (at least it does in Australia!) - which effectively means that only pure sine wave inverters qualify.

 

[staticV3]

Don't be so fast to say your audio equipment wouldn't care..

Amirm did the test using a Topping A90 which is using 2 x all-in-one power module (IRM-20-15).

A Loxjie P20 was also texted and it too did not care about the light dimmer AC.

 

[lisgotan]

A Loxjie P20 was also texted and it too did not care about the light dimmer AC.
View attachment 251048

The Loxjie P20 does not have its own built-in power supply, so an external adapter is needed. I don't know what power adapter he is using but vast majority of the factory made adapters would include EMI filter. If you open up a power adapter, you will see things like filter caps, common mode chokes, DC filter diodes etc. The filter also works to prevent noise from equipment into power line.

So, AC power filter is actually very important. However, its already built right into power supply of the equipment. Thats why it does not seems to matter.

Btw, not all audio gear comes with power EMI filter.