MSB S202 Stereo Amp

The above is a decent explanation. In a perfect circuit (purely resistive) voltage and current align. In a reactive circuit (inductive v capacitive) which occurs most often (motors and coils) the current lags the voltage.

I look at it like this: it takes time to develop the magnetic field (and current to flow), once a voltage is applied to a coil. Therefore current lags voltage. The opposite happens when you remove the voltage: the magnetic field takes time to collapse. This sets up the more complex power triangle shown on the link since P=V*I.

I’m sure others here can explain it way better. BTW, I’m actually an aeronautical engineer working in electrical distribution (don’t tell anyone).

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Thanks very appreciate but still too hard for a journalist (like me) to fully understand sonically how this impacts on my system. I try to carefully read again this evening the explanation before giving up.
Sorry for my complete ignorance.
Next Monday I’ll share with you the diagnosis from the electrical engineer.

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Have no idea how PF affects sound but it makes the circuit (at those values) inefficient. That is, the circuit could trip at lower current values. It takes more current to satisfy the circuit on one half cycle and less on the other half. The total is the same but the first half cycle could trip the circuit (not at 1.8A).

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Regarding PF (power factor) as @amsco15 points out there’s a displacement portion (phase shift between current and voltage) and there’s a distortion portion often caused by passive rectification feeding filter capacitors found in most electronics. A PF of 0.6 is really low indeed. Although most audiophiles cringe when hearing “switching power supply” some of these offer active power factor correction which “chops up the current” in a way that approaches ideal PF of 1.0.

Typical input current charging power supply capacitors:

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The ideal power factor would be 1.0
A pf range of 0.8 to 0.98 is typically considered good.
Lower power factor requires more current to do the work required by your component. This can cause excessive heat and can actually damage your component.
A power factor of 0.5 draws twice the current to satisfy the component requirements.

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Two questions:

  • my P20 should fix this issue or could be affected from it?
  • why this value is lower after few components are powered off?

I’m putting money on the P20 causing the issue on the line side of the P20. Assuming it helps on the load side. Don’t know for sure (of-course), don’t yell at me Paul.

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Powering off, one by one, the components the PF value decreases consequently from 0.60 to 0.50, to 0.40 till 0.30 with all the system off except the P20. On the contrary the cosine value goes from 0,59 to 1 and there it stays, once I power off the M1200s and subs.

Very interesting! It seems P20 acts as a class A amp. I read from somewhere that when Class A amp is on but with no load it consumes the most energy.

Not sure how the meter is set up but it’s reading 1-PF….zero being perfect and cosine (O degrees) = 1. A zero angle being resistive power only.

To test if the P20 is causing reactive power, plug your gear into the wall bypassing the P20.

The electrical engineer was more focused on cosine value, he said 1 is perfect. After having powered on the system it went to 0.56 and he said, no no it’s not good. If confirmed after a week monitoring the power we can fix it installing an inverter before the panel to keep this value always at 1.
Didn’t understand at the moment but he promised me a clarification as soon as he’ll be here to read what the meter unit has been recorded.
Bad thing ignorance!

Hi @dchang05 and all members following my last Puritan experiments.

Here I am. Time to try the Puritan 156 feeding the DAC in my system. As promised.

First step.
I needed to plug the M1200s back to the wall sockets (each one to a dedicated line). I gave them a couple of hours in order to become familiar with the sound.
Let me say that without the Puritan feeding amplification is a different system. I already arrived to this conclusion a few weeks ago and my previous thoughts are confirmed. The M1200s plugged straight to the wall are loosing separation, detail, openness. In one word: they are are less revealing. The soundstage presentation is lacking depth, less layers than I was used with the Puritan (or the P15) and I’m not able to locate the instruments. Bass are rounded but less tight, a veil raised up like a subtle curtain of fog. Voices are less focused, I feel less emotional impact and pleasure. The magic is gone.

Second step.
I plugged the Puritan to a dedicated socket available, feeding just the MSB DAC. Amplification on the front wall as described above. Pre and sources, as usual, all fed by the P20.
Wow, I say wow! The difference is immediately evident. The singer’s voice emerged instantly with realism, capturing my attention. Little details and sounds raised up from different sides and layers of the soundstage, right left backwards and forwards. Bass became less prominent and precise. Guitar strings sound is stunning, simply wonderful. The black background was back with all nuances audible again, like steps on the stage or clapping people during live performance. The fog has vanished. Think about a deep blu sky and fresh air day, when on the horizon you are able to see mountains far far away as they were closer to you. Transients and attacks are superb, so engaging. No harsh, bright or excess on the entire spectrum of frequencies. It means no fatigue, so to speak. Tons of details, again. Realism.

The combo P20 and Puritan sounds great, no doubts.

At this point I need to have more critical listening to understand if I prefer the Puritan feeding the M1200s or the DAC. Not so easy, some qualities are similar, like clarity. Others are different, like tonal balance and overall presentation, where feeding the DAC the upper frequencies are cleaner but with less separation of instruments and less depth of the soundstage.

The Puritan IME is not a conditioner for all components, able to feed the entire system, here the P20 is the best and unbeatable solution. Having said that, I need two different regenerators: one for pre and sources on the side wall and another for amplification on the front wall. I started my experiments with this aim. Here the Puritan is capable to deliver its best performance, it requires a few experiments but the result is amazing. Think about the Puritan as something to be added, not something able to replace a P15/P20. Searching for synergies exactly like we are used to do with AM-1, SR Purple and Master fuses. Or different tubes. Or an audiophile switch in the chain.

Maybe in my mind is raising the dangerous idea to try 2 Puritans and a P20 all together. It comes with its Ultimate cable, so another Dragon PC isn’t needed. Too early to say things like that sorry. Keep calm and let the music play.

Hope that helps.

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Hi Luca, this is another review that gives me a good understanding what Puritan can do. Thanks!

Your point of Puritan 156 is not a replacement but an add-on may be a great solution for me, and many others. In my particular case, upgrading P15 to P20 may not be the best solution anymore. :pray:

Keep up the good work! :clap:

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Thanks Donald, exactly… an “add-on” conclusion is what I’m referring to.

If you have the opportunity to combine a home audition with a US dealer, I highly recommend you to go this route, no risks other than a new purchase in your future.

Can’t say if my conclusions are related to my particular home power quality, or general 230 V current environment (similar to Puritan engineer background) or specifically to MSB DAC. Who knows? If you can, give it a try. If it doesn’t work in your system you can always send it back.

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Unfortunately there are very few dealers near my area now. I can check if SF area has one that carries it.

My P15 is fully loaded. As long as I am not adding another gear requires power then I am okay. But I will probably get a Puritan 156 eventually. Thanks!

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Another option would be to power the M1200 to the P20 and the rest through Puritan

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@luca.pelliccioli must be worn out with all the testing of so many combinations, hard to keep score

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Yes and no.

It’s an option, for sure. But…

  • I’m not able (or simply I don’t want) to move it just for an experiment, due to weight
  • I prefer considering pre and sources as a better choice for the P20, at least I’m supposing it
  • I’m afraid I’d missing the sound it is capable of if I change its setup, I think its role is crucial where it is now
  • It isn’t worth the try having read about competent members that already tried using the Puritan for the largest part of components, replacing the P20
  • P20 is maybe overkilled just for M1200s

I prefer living with the doubt than facing that kind of challenge.

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You are right!

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