• WANTED: Happy members who like to discuss audio and other topics related to our interest. Desire to learn and share knowledge of science required. There are many reviews of audio hardware and expert members to help answer your questions. Click here to have your audio equipment measured for free!

Thoughts on power conditioners?

Wombat

Master Contributor
Joined
Nov 5, 2017
Messages
6,722
Likes
6,459
Location
Australia
I am pondering getting a power conditioner. However, I thought I would ask what the "objective" view on power conditioners is.

This is the story - the power supply in my house varies between 220V and 260V. I don't think I can hear the fluctuation in power supply, but over the years I have had various equipment failures which have been blamed on the power supply.

For example, my Cary CAD-211AE monoblocks are manufactured in the USA. These amplifiers sound wonderful, but they are unreliable and blow something every 12 months. My engineer believes that these may be due to power supply variations - he noted that the capacitors were under-rated for Australian conditions (particularly when the input voltage exceeds 250V) but would be perfectly safe for the US market. When I asked why, he said that manufacturers think differently to DIY'ers - the most important thing for a manufacturer is to ensure consistent delivery of parts, so they tend to settle on what is most available for a long period of time.

Another example is my JL Audio subwoofer, which has blown its amplifier board twice within five years. It was repaired by a different engineer, but he too blamed power supply variations.

My main motivation for wanting a power conditioner is not so much to improve the sound (although that would be welcomed) - but to avoid equipment failure from power spikes. However, I must confess my ignorance when it comes to electronics, so I have to ask the question to people who would know.

What is your take on this? What is the best type of power conditioner to get?



Objective(experienced) view: http://sound.whsites.net/articles/mains-quality.htm
 

Fitzcaraldo215

Major Contributor
Joined
Mar 4, 2016
Messages
1,440
Likes
632
I succumbed to the power conditioner hysteria in the mid-90s, convincing myself I needed one. I bought a PSAudio 600w monster of an AC regenerator and used it for everything low power and excluding my amps. A decade later, it bricked, but they offered a nice trade anyway on a new, much smaller P5.

Relistening to it in vs. out this time, I really heard no significant difference. Maybe I am lucky in my urban power situation or maybe I just wised up. I still use it because it has a nicely programmable turn on/off feature. That allows simple turn on/off for my system outlet by outlet via my little Harmony remote and wifi. My main Class D amp bypasses it and is on all the time. My center and surround AB amps also bypass it for power but they have 12V triggers, and I found a 12v wall wart to plug into the PS to turn those on/off via remote control. But, DAC, TV, etc. do still use it for power.

I remember well the days when every reviewer in every magazine considered power conditioning an essential part of the system. Every review for awhile included one, even on the amps because they swore "it made a 'positive' difference", with much creative prose to describe and extol it. Later, I discovered how power limiting, particularly on amps, was a significant measurable factor. I think it was Peter Moncrieff in his International Audio Review who debunked the positives of it with measurements of a number of them. He was good and bad, himself over the years, but here he was useful, opening my eyes and others to the issue.

I concluded the magazine reviewers sure had been hearing something, but it was not good, like they assumed. And, all those countless reviews using power conditioning with amps were worthless. Fortunately, most of that fad has quieted down, though sanity still does not prevail in all cases.
 

amirm

Founder/Admin
Staff Member
CFO (Chief Fun Officer)
Joined
Feb 13, 2016
Messages
44,368
Likes
234,384
Location
Seattle Area
I too have a programmable PS Audio power regenerator. I used to power my DAC with it at work (Microsoft). There, I thought it had its best fidelity at higher than 60 Hz mains frequency. Surprisingly my DAC would put up a mains fault on its display if I dialed up the frequency too far! One of these days I plan to replicate that setup and see if there is a change in the DAC output with respect to frequency.
 

RayDunzl

Grand Contributor
Central Scrutinizer
Joined
Mar 9, 2016
Messages
13,198
Likes
16,981
Location
Riverview FL
I too have a programmable PS Audio power regenerator.

Oh no!

I hope it isn't the original P-300.

psaudio300.jpg


Don't electrocute yourself... It has balanced outputs.

https://www.stereophile.com/powerlineaccessories/181/index.html
 

Jerry Sobel

Active Member
Forum Donor
Joined
Feb 15, 2018
Messages
122
Likes
88
Great thread! I unplugged most of my gear from my "power conditioner" about 3-4 months ago to see if I could hear a difference with my turntable and I never plugged stuff back in. After reading this thread I realized I had done this and I think without it my system sounds better.
Time to sell.
 

stunta

Major Contributor
Forum Donor
Joined
Jan 1, 2018
Messages
1,155
Likes
1,399
Location
Boston, MA
Some of the "audiophile" power conditioners are current limiting. Best to avoid them on amps and subwoofers. They have the effect of floppy bass which some people like (I know, dont ask). I got into those at some point (I was probably having some deep psychological issues, haha) for my sources/pre-amp but managed to sell them off without taking too much of a hit. Eventually, I settled on the APC H15 and grabbed two of them when they were on sale. The features are quite nice including voltage regulation (questionable value where I currently, but I just like having it) which most of the audiophile conditioners don't have. Lots out outlets including two high-current ones for amp/sub. If it is improving the sound quality, I haven't noticed it. Connected equipment warranty is quite good as well.
 

Speedskater

Major Contributor
Joined
Mar 5, 2016
Messages
1,610
Likes
1,333
Location
Cleveland, Ohio USA
Some of the "audiophile" power conditioners are current limiting.
While some may may be current reducing, by dropping the line voltage a couple of volts or so, all this does is reduce the power amps maximum power before clipping. Same as changing the line voltage. My line voltage may be anywhere from 115V to 125V thru the month and I don't notice any audible difference.
The only thing in an AC power system that limits current are the circuit breakers.
But then who needs a so called power conditioner anyway?
 

amirm

Founder/Admin
Staff Member
CFO (Chief Fun Officer)
Joined
Feb 13, 2016
Messages
44,368
Likes
234,384
Location
Seattle Area
While some may may be current reducing, by dropping the line voltage a couple of volts or so, all this does is reduce the power amps maximum power before clipping.
I think he is referring to series type surge protectors. They have an inductor in series with the load so the power handling of that becomes the limiting factor.
 

trl

Major Contributor
King of Mods
Joined
Feb 28, 2018
Messages
1,967
Likes
2,523
Location
Iasi, RO
I am pondering getting a power conditioner. However, I thought I would ask what the "objective" view on power conditioners is.

This is the story - the power supply in my house varies between 220V and 260V. I don't think I can hear the fluctuation in power supply, but over the years I have had various equipment failures which have been blamed on the power supply.[...]

Another example is my JL Audio subwoofer, which has blown its amplifier board twice within five years. It was repaired by a different engineer, but he too blamed power supply variations.

My main motivation for wanting a power conditioner is not so much to improve the sound (although that would be welcomed) - but to avoid equipment failure from power spikes. However, I must confess my ignorance when it comes to electronics, so I have to ask the question to people who would know.
[...]

As ohers said already, you need an AVR, a voltage stabilizer. I have APC Line-R and an Apollo AVR at home, which uses microcontroller and power relays combined with an autotransformer, but I also have step motor autotransformer that adjusts the output voltage in real time in very small steps. I also have an electronic power outlet with a relay inside that cuts off output power if input power is outside normal limits (in my case: >210V & <250V).

WP_20170129_13_54_27_Pro.jpgWP_20170129_13_56_24_Pro.jpgWP_20170129_13_55_55_Pro.jpgWP_20170129_13_55_09_Pro.jpg

WP_20170128_21_18_24_Pro.jpgWP_20170128_21_17_48_Pro.jpg

WP_20170124_17_18_45_Pro.jpgWP_20170124_17_08_02_Pro.jpgWP_20170124_17_07_38_Pro.jpgWP_20170124_17_07_09_Pro.jpgWP_20170124_16_58_07_Pro.jpgWP_20170124_16_57_16_Pro.jpgWP_20170124_16_50_34_Pro.jpgWP_20170124_16_44_27_Pro.jpgWP_20170124_16_39_18_Pro.jpgWP_20170124_16_35_58_Pro.jpg

Hope this helps.

P.S.: I also have a Schneider iMSU that protects all home appliances from really big power surges/overvoltages, but also in case Null diconnectes (Phase could get returned from nearby houses).
 

JJB70

Major Contributor
Forum Donor
Joined
Aug 17, 2018
Messages
2,905
Likes
6,148
Location
Singapore
Marketing for cables and power conditioners tends to rely on identifying a kernel of truth and then completely misrepresenting that kernel of truth and taking it way out of context to the point where it becomes dishonest.
 

trl

Major Contributor
King of Mods
Joined
Feb 28, 2018
Messages
1,967
Likes
2,523
Location
Iasi, RO
Sometimes, when home's input power is really bad, with lot of distortion and maybe some DC as well, a power conditioner might help in futher preventing damage to home appliances and electronics. Reconstructing the waveform of the mains to lower the distortions, removing the DC fro mmains to protect your Hi-Fi equipment's transformers and getting rid of power line noise will definitelly improve the quality of the mains. However, depending on how bad is your power line and what type of the power supply your DAC & amplifier is using this doen't means that your Hi-Fi equipment will sound better, but someimtes this might be the case indeed.

Here, https://www.ixbt.com/power/ups-test-nov2k1.shtml, at "Powerware 5115 750i", the guys from IXBT did lot of measurements of UPS-input vs. UPS-output, so look at the input wave of this specific Powerware UPS and you'll see that output of UPS is showing much improved, more like a sinewave than the input. I'm happy that in my home power input looks much better that in IXBT picture and I don't need to worry about poor mains sinewave. :)

I've attached some pics from my home's power supply and from Emerson GXT3 and Legrand NikyS pure sinewave UPS's, as I don't own a power conditioner to compare, but operating principle is the same: good EMI/RFI filter + reconstruction of mains waveform. All measurements were done via a 230V-120V isolation transfomer.


Power_outlet_01.png

Mains power from E.On

Sinusoida_Emerson-GTX3_01.png

Emerson/Liebert GXT3 (this was measured with a different isolation transformer)

NikyS_sine2.png

Legrand NikyS

Ground_to_Neutral_noise_plain.png

Noise between Ground and Neutral from my home mains with no appliances running


Ground_to_Neutral_noise_vacuum_max.png

Noise between Ground and Neutral from my home mains with vaccum cleaner plugged and running in the same outlet as Hi-Fi

Power_outlet_02.pngPower_outlet_04.png
Mains FFT up to 10MHz

GTX3_10MHz_magnitude.pngGTX3_10MHz_average.png
GXT3 FFT up to 10MHz

NikyS_10MHz_magnitude.pngNikyS_10MHz_average.png
NikyS FFT up to 10MHz

Given the good quality of my input mains I see no reason for me to use a power conditioner (or an true-online & pure sinewave UPS). Perhaps a better EMI/RFI filtering between GND and NULL (heigher capacity for the Y/Y2 caps from within the EMI/RFI filter) might help, but till then I'll just not use the vaccum cleaner when listen to music. :)

I also don't recommend purchasing a power conditioner unless really needed, based on measurements of the mains waveform and noise.

NOTE: Unless you do have proper testing equipment (differential probes would be the best) and some knowledge, I strongly don't recommend you to measure mains quality by yourself!!!
 
Last edited:

Speedskater

Major Contributor
Joined
Mar 5, 2016
Messages
1,610
Likes
1,333
Location
Cleveland, Ohio USA
The two best questions to ask the power conditioning people:

1] How much does it improve the signal-to-noise ratio at the audio output of the hi-fi equipment setup?

2] How much does it reduce the out of band high frequency noise at the audio output of the hi-fi equipment setup?
 

trl

Major Contributor
King of Mods
Joined
Feb 28, 2018
Messages
1,967
Likes
2,523
Location
Iasi, RO
If your mains is looking fine, then NONE for both questions.

AFAIK a power conditioner does the following things:
- Gets rid of as much of the EMI/RFI noise (LC filters). This can also be done with inexpensive conditioners with EMI/RFI filters built-in.
- Surge and over-voltage protection, usually done with varistors (MOV), gas dischargers and fuses.
- AC regeneration from expensive conditioners will restore your AC mains perfect sinewave (like the above UPS's with true-sine inverters do). This may also lower the distortions and harmonics of the regenerated mains, but will also remove any existing DC voltage. Usually, DC voltage, sine-wave distortions and harmonics from your mains may affect the performance of your linear PSU or switching-mode PSU (this doesn't necessary means your audio chain will sound worse!).
- Big caps from inside might be a good buffer for fast transient response.
- Expensive conditioners might have balanced isolation transformers inside. This usually reduces AC noise even further and offers a very good level of protection (eg: ground fault protection, but also balanced power is not harmful to people if only one wire gets touched).
- Optionally, may safely remove the ground.

If your mains looks like crap, with lot of noise and some DC voltage combined with a distorted sinewave and your Hi-Fi equipment is having inside very sensitive AC-DC/DC-DC regulators, then a power conditioner might help. Also, a power conditioner may decrease some hum (50-60 Hz) or some noise (usually when no music is playing, between the songs).

In conclusion, I can't say it better than the author of this: https://samplerateconverter.com/educational/power-conditioner#conclusions. So, clean AC getting into your Hi-Fi system doesn't means the speakers output will be cleaner. After all, the internal power supply of a Hi-Fi equipment is a power conditioner itself.

Some nice specs and inside pics from Niagara 7000: https://www.audioquest.com/page/aq-niagara-7000-internal.html.

However, if someone with a crappy mains lines at home and a power conditioner can let us know more details (read measurements) then please speak up. :)
 

Frank Dernie

Master Contributor
Forum Donor
Joined
Mar 24, 2016
Messages
6,445
Likes
15,780
Location
Oxfordshire
Properly designed hifi is presumably intended to be plugged into the mains so surely if it doesn't perform properly when plugged directly into the mains it is a poor design and should be avoided?
The only mains supply I have experienced which caused problems was at the end of a long supply in deepest rural France and the voltage went low enough from time to time for my UK spec CD player to malfunction, but that was a 240 volt item plugged into a nominal 220 volt supply which dropped below 200V sometimes.
 

trl

Major Contributor
King of Mods
Joined
Feb 28, 2018
Messages
1,967
Likes
2,523
Location
Iasi, RO
Usually, internal Hi-Fi power supplies are carefully designed and work perfectly as intended. If your 120/240V mains is really crappy and noisy, then bad things might happen, from equipment distruction (even fire when lightning or power sourge take place), to hum and noise injected into speakers (I’ve actually heard radio waves once, but I’m sure it was from a bad/inexistent mains ground combined with an oscillating circuit from a DIY headamp).

In case of fluctuating mains an AVR stabilizer should suffice. It usually consumes 10W/h and costs 100-200 USD; it also has basic EMI/RFI filter inside and overvoltage protection.
 

trl

Major Contributor
King of Mods
Joined
Feb 28, 2018
Messages
1,967
Likes
2,523
Location
Iasi, RO
The two best questions to ask the power conditioning people:

1] How much does it improve the signal-to-noise ratio at the audio output of the hi-fi equipment setup?

2] How much does it reduce the out of band high frequency noise at the audio output of the hi-fi equipment setup?

1) If there is mains hum or barely audible noises in your speakers (between the songs or when no music is playing) then a power conditioner might get rid of these.

2) Usually amplifiers have low-pass filters to prevent unwanted oscillations, that means there should be no out-of-band noise. However, for high bandwidth amplifiers (>100 KHz) a conditioner might help a bit, though not sure is really needed (a scope would be better here).
 

maverickronin

Major Contributor
Forum Donor
Joined
Jul 19, 2018
Messages
2,527
Likes
3,308
Location
Midwest, USA
I have a bunch of Powervar conditioners I've scored pretty cheaply from stalking ebay. They're mostly for paranoia about spikes and surges breaking things.
 
Top Bottom