P5 Disappointment


#1

After initial use when I thought the P5 maybe helping my poor powerline, subsequent listening at various times throughout the day has brought me to the conclusion that it doesn’t perform as I had hoped, and in some instances makes things worse. Listening is only possible in the wee hours when my power is least corrupted. I have contacted the county utility for answers but that will not result, I fear, in a speedy resolution. :frowning:


#2

It might be helpful if you post more details (what settings on the P5 you are using, the THD in/out, etc.). Some of the more technically adept folks could offer suggestions or at least help you understand what’s happening with your power. Also, what’s feeding the P5; do you have a dedicated line? are there any large appliances on the same circuit?


#3
magister said It might be helpful if you post more details (what settings on the P5 you are using, the THD in/out, etc.). Some of the more technically adept folks could offer suggestions or at least help you understand what's happening with your power. Also, what's feeding the P5; do you have a dedicated line? are there any large appliances on the same circuit?
THD in 5.8%,THD out 0.6%, settings are default. Tried different ones. No affect. Max total load 300w from tube preamp, tube power amp and TT motor controller. 20 amp dedicated line.

#4

What is it about the sound that makes you unhappy when those components are powered by the P5, compared to wall power?


#5
brodricj said What is it about the sound that makes you unhappy when those components are powered by the P5, compared to wall power?
When my system sounds best, meaning in the wee hours, it is plugged into the wall and has an ultra smooth, very detailed, natural, relaxed presentation with saturated images and captivating textures of acoustic instruments, while the soundstage proportions and transparency are thrilling. If I plug all the components into the P5 at this time, the result is a clinical, somewhat bright and "hi-fi-ish" sound with a less dimensional stage. The degree of audible impairment depends on the complexity of the recording. I listen mostly to classical and jazz. The worst offense is heard in daylight hours on orchestral recordings or vocals where massed strings and massed voices appear as a gritty, muddy mess which one could easily believe contain 10 or more percent of harmonic distortion.

The problem is definitely on my powerline. I have eliminated my components as culprits by swapping them out with other known good components. The RFI/EMI inspector from the county utility scanned my house and the neighbors and concluded there is an external noise source which remains to be identified. My system and I were happy as clam until December 2 of this month when I started noticing some mild distortion which only increased over the next few days.


#6

So, if I’m to understand this correctly, prior to Dec 2 you were happy with the sound of your system when powered by P5, however something has happened to the nature of the incoming power since then that somehow now makes the P5 powered system sound worse than when it is powered directly from the wall?


#7
brodricj said So, if I'm to understand this correctly, prior to Dec 2 you were happy with the sound of your system when powered by P5, however something has happened to the nature of the incoming power since then that somehow now makes the P5 powered system sound worse than when it is powered directly from the wall?
Not quite. I did not have a P5 prior to Dec 2. I ordered one several days later in an attempt to mitigate the problem. I have discovered that it is unable to correct the problem and in addition, doesn't sound as good without it in the wee hours. I should also mention that the THD of 5.8% I previously reported I don't necessarily believe. I had the opportunity to borrow from a dealer an Isotek EVO3 conditioner which consistently displayed THD of about 3% higher.

#8

What is the difference between voltage input/output?


#9
brodricj said What is the difference between voltage input/output?
1 volt or less

#10

Maybe the dealer can loan you a P10, see if that brings improvement. Given your P5 is new they might just let you trade-up for the price difference, that is, if the P10 solves the problem for you.


#11
brodricj said Maybe the dealer can loan you a P10, see if that brings improvement. Given your P5 is new they might just let you trade-up for the price difference, that is, if the P10 solves the problem for you.
Kinda doubt a P10 would do it given the present circumstance. Unless the power company can give me some answers, the only alternative may be a storage solution with charge controller and low noise inverter.

#12

…or just accept it for what it is. The power utility is unlikely to do anything about it. An isolation transformer would be the next step to try over a battery/inverter system.


#13

Just brainstorming: The noise may not be getting in to the system via the AC. It might be something like a new cell tower in the neighborhood, or whatever. Then the rehabilitations might involve better shielding on some cables or at least revisiting how the cables are dressed - too many cables in parallel is bad, etc. Or perhaps better grounding on sensitive equipment…


#14
Ted Smith said Just brainstorming: The noise may not be getting in to the system via the AC. It might be something like a new cell tower in the neighborhood, or whatever. Then the rehabilitations might involve better shielding on some cables or at least revisiting how the cables are dressed - too many cables in parallel is bad, etc. Or perhaps better grounding on sensitive equipment...
I guess airborne stuff is possible. I'll try shielding the phono cables which carry a 0.3mv signal.

Also an isolation transformer might be worthwhile. The only one I’m aware of that might work is Torus which uses a Plitron narrow band transformer to attenuate noise.


#15
miniguy said I should also mention that the THD of 5.8% I previously reported I don't necessarily believe. I had the opportunity to borrow from a dealer an Isotek EVO3 conditioner which consistently displayed THD of about 3% higher.
They are probably both wrong; neither contains laboratory quality measurement kit within the unit, merely an aproximation.

More importantly, how did the Isotek sound?


#16

As far as I know the Powerplants don’t stop noise getting through on the ground, so if that is the problem the isolation transformer should be the fix. But if the noise is on the ground I don’t know how the P5 would make your system sound worse than when it is connected directly to the wall with a bad ground.


#17
Elk said
miniguy said I should also mention that the THD of 5.8% I previously reported I don't necessarily believe. I had the opportunity to borrow from a dealer an Isotek EVO3 conditioner which consistently displayed THD of about 3% higher.

They are probably both wrong; neither contains laboratory quality measurement kit within the unit, merely an aproximation.

More importantly, how did the Isotek sound?


It is a passive conditioner and did no better than the P5 in mitigating the problem, though it did lack the clinical quality I noticed from the P5. It would be interesting to try what looks to be the king of AC regenerators, the Accuphase PS-1230, but that’s not likely. Besides it’s $17K.

#18
brodricj said As far as I know the Powerplants don't stop noise getting through on the ground, so if that is the problem the isolation transformer should be the fix. But if the noise is on the ground I don't know how the P5 would make your system sound worse than when it is connected directly to the wall with a bad ground.
Good question. I will look into borrowing a Torus.