PS Audio P12 Review Part 2: Power Testing

[respice finem]

How is this even possible? I thought those conditioners are - according to what I learned here - pure snake oil?

As a non-engineer, I can only say the little Furman worked for me in this particular case.

 

[DonR]

As a non-engineer, I can only say the little Furman worked for me in this particular case.

The Furman is a filter, not a true conditioner like the PowerPlant. Sometimes even a simple power strip can solve a ground loop.

 

[amirm]

@amirm : I would be interested to know what impedance the Ideal measures on your BK Precision 9801.

Just tried this and it reads just 0.4 ohm. So smoke thickens with respect to high readings of P12.

 

[respice finem]

The Furman is a filter, not a true conditioner like the PowerPlant. Sometimes even a simple power strip can solve a ground loop.

The power strip didn't help, and yes it's SOT here. It wasn't a ground loop either, IDK what it was exactly, simply intermittent (irregularly) clicks and protection LED on for a second in both active speakers.
The Furman was this one: https://www.thomann.de/de/furman_ac210_power_conditioner.htm

 

[DonR]

The power strip didn't help, and yes it's SOT here. It wasn't a ground loop either, IDK what it was exactly.
The Furman was this one: https://www.thomann.de/de/furman_ac210_power_conditioner.htm

Yes, that Furman model is a simple filter with overvoltage cutout as can be seen from its internals:

 

[respice finem]

Yes, that Furman model is a simple filter with overvoltage cutout as can be seen from its internals:

So probably there were just some voltage spikes. There are many potential sources of interference where I live, from heavy insustry to agriculture.

 

[DonR]

So probably there were just some voltage spikes.

Possibly, a good quality surge protector with some filtering capabilities would probably work just as well.

 

[respice finem]

Possibly, a good quality surge protector with some filtering capabilities would probably work just as well.

Not the ones I have at home - but as said, the Furman did the trick.

 

[DonR]

Not the ones I have at home - but as said, the Furman did the trick.

The Furman looks fairly robust so likely you needed something stronger. I use this on my AVR:

Next Gen 120 - 208V Surge Protector, Power Filter, and Power Management Software

The Next Gen Power Conditioning System combines advanced power protection with analytical software to proactively mitigate and manage power quality events.

www.ametekesp.com

 

[Hayabusa]

Also, the big deal in this review was not the impedance measurements but rather, how power dropped in a real amplifier with P12. The claim that the P12 somehow delivers more power kept repeating in the other review thread. So I put it to test and the outcome was the other way around with P12 reducing power by almost 10% -- both peak and continuous. If you were going to ask PS Audio something, this would have been the question to ask. Remember, you listen to audio devices, not the impedance of AC power.

@amirm I gave you a possible reason for this? ( see my previous response).
Did you check input v.s output voltage?

Unfortunately I can't perform dual measurements like this. AP is tied up performing the amplifier measurement and can't be used to simultaneously measure the AC. Standard tools I have for voltage measurements (e.g. meters) are too slow to track the activities of AP trying to determine power.

I tried looking at the P12 meters but they are ridiculously slow and as such, useless for this purpose.

At the end of the day, it doesn't matter "why" but the results we achieved.

I disagree, it matters. Is't science the reason you want to know why?

I doubt it can regulate up. My bet is that the output voltage is always lower than the input.

It can regulate up.

 

[amirm]

I disagree, it matters. Is't science the reason you want to know why?

Not really. I rather test half a dozen audio products for which we don't have any measurements than to dwell on a product you all are not going to buy.

 

[Hayabusa]

Not really. I rather test half a dozen audio products for which we don't have any measurements than to dwell on a product you all are not going to buy.

@amirm: if you make a claim like "It is clear from the above tests that using the P12 degrades available power to an amplifier, not increase it. Both continues and dynamic power are limited, as they should", you better make sure it is backed-up.

Showing this happens in one specific situation is not really scientific.

I think the power difference is because your AC line voltage was higher than the regulated P12 output voltage.
If your line voltage would have been lower, the P12 would have increased the output voltage and your conclusion would be the opposite: It would increase output power of your amplifier.

 

[amirm]

@amirm: if you make a claim like "It is clear from the above tests that using the P12 degrades available power to an amplifier, not increase it. Both continues and dynamic power are limited, as they should", you better make sure it is backed-up.

They were backed up. I showed you measurements.

Showing this happens in one specific situation is not really scientific.

Claim was made unequivocally that P12 increases dynamic power of amplifiers due to its low output impedance. All it takes to show this to not be the case is one example. This is how science works.

I think the power difference is because your AC line voltage was higher than the regulated P12 output voltage.

Where is this documented by the company? How is the owner supposed to know this?

 

[Hayabusa]

They were backed up. I showed you measurements.


Claim was made unequivocally that P12 increases dynamic power of amplifiers due to its low output impedance. All it takes to show this to not be the case is one example. This is how science works.


Where is this documented by the company? How is the owner supposed to know this

I suggested that a new measurement could give you a very different result.
If so, it was an incomplete measurement.
Do you still have the P12? Please repeat the measurement where you input the P12 a lower voltage (Variac?) and check the power outputs again.

About the PS audio claim: I agree here with you, their claim that it will always increase dynamic power is false. For instance if the input line voltage was already good enough to start with it would not change anything.

The P12 is spec-ed as a regenerator that outputs a constant output voltage regardless its input.
So 110v in would give you 120v out as well as 130v in would give you 120v.
May be that's not 100% explained in the PS audio spec but that the way in general a power regenerator works.

 

[voodooless]

Mind you, we’re talking about a .35dB difference in output power here

 

[voodooless]

I suggested that a new measurement could give you a very different result.

That doesn’t matter, does it? They made a claim, and that claim was falsified. End of story.

There are no asterisks next to the claim explaining that actually voltage input determines if you get more ore less power. They even tell it’s due to output impedance.

 

[solderdude]

An interesting measurement @amirm could do is compare the output of the amp once driven via the PP and once driven from the B&K both set at the exact same voltage (the output of the tested power amp is mains voltage dependent)

When mains voltage would sag to say 110V the poweramp would have less output then when driven via the PP (which is 120V).
Alternatively when mains voltage is say 125V the PP would give lower output power.

When testing using a device that is mains voltage dependent the mains voltage should be 'level matched'.

 

[Hayabusa]

That doesn’t matter, does it? They made a claim, and that claim was falsified. End of story.

There are no asterisks next to the claim explaining that actually voltage input determines if you get more ore less power. They even fail it’s due to output impedance.

You are 100% right.
But I really hope the goal of ASR is not to focus on disproving claims from equipment makers using absolute statements.
Sometimes you need to read between the lines and be open for the actual claim.
I am quite sure also Paul from PS audio realizes that a P12 can improve sound in 'some' situations and will make no difference at all in many other situations and can even worsen sound in other situations.

 

[solderdude]

They even fail it’s due to output impedance.

I don't know. It isn't hard to build a 1kW (balanced) amplifier with lots of feedback to make it have an output R of less than 0.01 ohm.
This basically is what the PP is. An amp (with some headroom so it can still put out 120V even when fed with 95V AC) fed by a 60Hz sine oscillator.

 

[restorer-john]

About the PS audio claim: I agree here with you, their claim that it will always increase dynamic power is false. For instance if the input line voltage was already good enough to start with it would not change anything.

On the end of a long extension lead playing sine waves at high power, the PS Audio may be able to produce more power in a connected amplifier than direct, but that would only be due to the voltage drop on a direct connection.

The 500mS EIA/CEA toneburst (20mS 0dB, 480mS -20dB) shouldn't really sag the PS Audio's output and neither should it sag the direct feed. But again, it depends on how much power is being pulled in the first place. In practice, there is little to no difference in dynamic output results with either the EIA/CEA or the IEC/JIS toneburst which you would think not to be the case. On quality amplifiers I measure there is no appreciable difference. Certainly not worth jumping up and down about.