It would probably be cheaper to do it that way.
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PS Audio P12 Review Part 2: Power Testing
- Thread starter amirm
- Start date
The bottom line claim for this device appears to be that it makes a higher input voltage available to a power amplifier at those moments when transient demand is highest: in simplest terms, when the music is loudest. I see nothing in the testing that suggests the PS12 actually accomplishes that. Am I wrong?
Secondarily, would one not be better advised to install a gas- or propane-fueled generator to produce AC power specifically for one's amplifier if one is concerned about dirty mains? Or how about something like a Tesla Powerwall -- will its AC output be cleaner than incoming mains?
It should be evident that I'm pretty ignorant about this stuff, but I'm trying to learn.
Secondarily, would one not be better advised to install a gas- or propane-fueled generator to produce AC power specifically for one's amplifier if one is concerned about dirty mains? Or how about something like a Tesla Powerwall -- will its AC output be cleaner than incoming mains?
It should be evident that I'm pretty ignorant about this stuff, but I'm trying to learn.
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solderdude
Grand Contributor
When flattening the top of the sine wave the peak current becomes lower as the charging time increases.
The charging current can be lower as it is smeared over a longer time period. The difference is small though.
solderdude
Grand Contributor
They existed. They aren't called re-generators though but generators.
Once I had worked with an old army surplus transmitter using tubes and it ran on 12V car batteries.
There was a DC motor inside that drove a generator making the needed AC voltages. You could hear it spinning.
You can also do this with a petrol or diesel engine powering a generator.
You can even get them to run pretty stable at a range of frequencies.
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I've worked with diesel powered hydraulic AC generators in oil field work and they have distorted waveforms. So even those are questionable.
MasterApex
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Your assertion that additional devices between wall outlet and your amplifier will "bottleneck" the raw power available seems to align with the product manual of Mark Levinson No 33 , which stated :
"In recent years, the detrimental sonic effects of noisy, unbalanced AC mains supplies have become widely known. Various passive AC “line conditioners” are available for use with line level components such as preamplifiers and digital audio processors to address these problems. In most cases, these line conditioners provide some filtering of the AC mains, along with some measure of surge protection. None of these devices may be used to good effect with power amplifiers, however, since they cannot handle the large instantaneous currents which power amplifiers require during normal operation. In effect, passive line conditioners become a “bottleneck” in the otherwise free flow of power through the amplifier to the speakers, reducing dynamic impact and musicality. In the Nº33, a more sophisticated approach is used that provides greater line conditioning benefits than the commercially available passive devices can hope to provide, while simultaneously avoiding any performance “bottlenecks.” A distortion-free 60 Hz sinewave is regenerated within the Nº33, and then used to power a separate power supply dedicated to all the voltage gain stages. AC power is delivered from the wall to the primary supply of the Nº33, where it is rectified, filtered and regulated into positive and negative DC voltages. A portion of this DC power is then used to drive an oscillator circuit which regenerates a pure 60 Hz sinewave without any of the noise or contamination so common to the AC mains as delivered to our homes by power utilities. The regenerated, pure sinusoidal AC wave is then sent to a dedicated secondary power supply, where it is converted to positive and negative DC power to be used by all of the voltage gain stages. This dedicated supply for voltage gain stages benefits from having a truly balanced source (unlike the dissimilar impedances of AC mains line and neutral), as well as from the total elimination of AC mains fluctuations and noise. As a result, the critical voltage gain stages of the Nº33 operate in a highly optimized environment, and are able to pass along significantly more low-level resolution and detail in the musical signal that they amplify. "
pinpoint_oxford
Active Member
I think it can give a little more current at spikes, but it depends on the amplifier too. Amir tested with a more demanding amp on the HC outlet that limits inrush current so it tested poorly in this regard. That said I'm not sure how effective the P12 is at this vs. mains outlet. Probably not enough to matter much for most (if not all) situations.
I'd say no. The mains AC is not as bad as home-use generators which produce very bad waveforms. I'd recon you would need to buy a very expensive generator to produce good AC and I doubt it would be worth it for audio especially due to all the actual noise it makes!
Likewise a powerwall or any solar/battery system creates DC which would have to be tranformed to AC. I'm not sure how the powerwall works specifically, but it would have to have a circuit similar to the P12 to generate the sine wave and AC current from DC. Could be better, or worse.
Any reasonably well-designed inverter generator or battery backup system is likely to produce an AC waveform that is at least as good as the waveform coming off of the grid, which, in the United States, is often much uglier than one would expect.
Some DC-AC Inverters have distorted durty AC output and others are much cleaner. A good one produces a pure sine wave/clean, utility grade power. One gets what they pay for and the good ones are expensive.
I've installed/wired up a very large 8 foot long industrial generator used in a fracking chem trailer and it had a distorted output. We questioned the integrity of the unit via my Fluke portable O-scope and sent screenshots to the manufacturer and they replied that this is the normal operation. Yet I've been in guided tours of hydroelectric dams and they produce a lovely looking 60 Hz waveform. The concepts are the same but for some reason the end result is different.
D
Deleted member 21114
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Wouldn't devices with a non-transformer PS run on DC? The DC would just pass through one half of the full wave rectifier? Or would heat issues from only using half the diodes cause trouble?
Yes, and probably (depending on rectifier rating compared with maximum load) yes.
solderdude
Grand Contributor
That would depend on what DC voltages are needed. Most amplifiers create + and - voltage rails from AC so a single DC won't work.
Also some devices have transformers with various voltages so one would need multiple batteries and some of them quite high voltages (which can be more lethal than AC) or by using a DC-DC converter.
Ironically these all convert DC -> AC -> DC and can generate HF noises when not done properly.
So the problem is not DC current through the rectifier but the need for multiple voltage rails.
The Powerwall + is advertised as an AC battery system. I believe its output is 120/240VAC as it contains an internal DC to AC inverter. It would be interesting to see what the quality is of its typical output.
OP
- Thread Starter
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Looked up the specs for Powerwall but it doesn't say anything about distortion or noise.
D
Deleted member 21114
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I have a powerwall and it runs my house from 4:00 PM to 9:00 PM most days in order to save on peak prices. Despite what Paul says I can tell no difference even if listening when it switches in. I have a 13 bit scope I could look at the wave form with but it can only measure distortion to about -65 db.
I guarantee Michael Fremer's 118 year old step grandmother-in-law would fly out of the kitchen 5,000 miles away and yell "Mikey, why does you radio sound like poop now?" if he had such a power setup in his basement.
I have a powerwall that runs all my house 24 hrs/day as I only use 5kw day for electricity and the power wall charges back up in the early of the morning when electricity is cheap, although cheap is now bloody expensive with the way electricity costs are in the uk at the moment.
No difference at all audio wise but I’m convinced my fridge is colder and the kettle boils faster.
No difference at all audio wise but I’m convinced my fridge is colder and the kettle boils faster.
That’s the distortion Paul talked about during his video.
In the thread on PS Audio's forums (https://forum.psaudio.com/t/heres-the-correct-way-of-measuring-a-power-plant) Paul has verified the Power Plants are not "traditional" Power Regenerators. He is stating they do something similar yet different. However these devices are and continue to be marketed and sold as Power Regenerators. Thoughts? I'm starting to feel these devices are extremely falsely advertised and misleading.
Thank you Amir for bringing all of this to light.
Thank you Amir for bringing all of this to light.
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