• 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!

PS Audio Noise Harvester AC Cleaner Review

solderdude

Grand Contributor
Joined
Jul 21, 2018
Messages
15,891
Likes
35,912
Location
The Neitherlands
I could have googled it myself :facepalm:
It just popped in my head with you mentioning the clock and linked that to 'old' clocks remembering them as always accurate while my cheap digital alarmclocks all tell a different time after a few weeks.
 

sergeauckland

Major Contributor
Forum Donor
Joined
Mar 16, 2016
Messages
3,440
Likes
9,100
Location
Suffolk UK
The grid frequency is adjusted to maintain a long-term average very close to 50 Hz, though I don't think the requirement is quite as strict as suggested. A few links on the topic:
https://wwwhome.ewi.utwente.nl/~ptdeboer/misc/mains.html
https://www.bbc.co.uk/news/world-europe-43321113
https://www.bbc.co.uk/news/science-environment-20629671
Very interesting, especially the bit about forensic analysis. Many years ago I met Hugh Ford who was an expert in tape analysis and it's the sort of thing he would have been all over.

Some months ago I visited Sizewell, and mains frequency accuracy was something they took very seriously. I'm pretty sure they said they keep the total number of cycles correct over a period, but maybe 'correct' is relative, not absolute.

S.
 

solderdude

Grand Contributor
Joined
Jul 21, 2018
Messages
15,891
Likes
35,912
Location
The Neitherlands
I could see audiophiles with synchronous motor driven turntables obsess over this. :)
I'll bet the harvester will improve things here as well.
 

audio_tony

Addicted to Fun and Learning
Joined
Feb 24, 2019
Messages
568
Likes
690
Location
Leeds, UK
I could see audiophiles with synchronous motor driven turntables obsess over this. :)
I'll bet the harvester will improve things here as well.

The harvester can't improve the frequency of the mains, and it's highly unlikely to make any difference to the running of an AC synchronous motor.

The only thing that'll improve that is a mains re-generator (assuming a 100% accurate clock).
 

mansr

Major Contributor
Joined
Oct 5, 2018
Messages
4,685
Likes
10,700
Location
Hampshire
Some months ago I visited Sizewell, and mains frequency accuracy was something they took very seriously. I'm pretty sure they said they keep the total number of cycles correct over a period, but maybe 'correct' is relative, not absolute.
It's impossible to guarantee that the number of cycles over any period will be exact.
 

solderdude

Grand Contributor
Joined
Jul 21, 2018
Messages
15,891
Likes
35,912
Location
The Neitherlands
The harvester can't improve the frequency of the mains, and it's highly unlikely to make any difference to the running of an AC synchronous motor.

The only thing that'll improve that is a mains re-generator (assuming a 100% accurate clock).

I was only joking and just wanted to get the thread back on track after my frequency derialment... left out the wink emoji as I reckoned it wasn't needed.
 

solderdude

Grand Contributor
Joined
Jul 21, 2018
Messages
15,891
Likes
35,912
Location
The Neitherlands
I remember one could buy 50Hz to 60Hz converters so you could use a US Hammond organ in Europe.
Modern re-generative UPS can also do this when it has such feature.
No idea how accurate they were.
 

solderdude

Grand Contributor
Joined
Jul 21, 2018
Messages
15,891
Likes
35,912
Location
The Neitherlands
To be fair, I did think you would have known better!!! Sorry :)

I am sure someone exists that feels his turntable sounds better when he plugged such a device in.
Also I wouldn't be surprised if an unsuspecting reader of this thread really thought... hmm that's an idea I will buy one.
In the latter case your response made it clear they need not try and saved themselves some bucks.... unless they were gonna buy one anyway.
I am sure meany people did, still do and in the future still will as 'we' only look at graphs and have no idea what sound quality really is.
 

audio_tony

Addicted to Fun and Learning
Joined
Feb 24, 2019
Messages
568
Likes
690
Location
Leeds, UK

It doesn't convert though?

Specs state:
Output Frequency (sync to mains) 50/60Hz +/- 3 Hz

"sync to mains" so 50 in 50 out - 60 in - 60 out....

I've looked in the manual and there is a set option - but I believe that just sets 60Hz (if on 60) or 50Hz (if on 50) but it's not exactly clear...

Unless the 'sync to mains' option reclocks the output frequency locked to the input frequency.

EDIT: Aha - I see it can convert - well that's new feature I've not seen before on these (although I've been out of IT for a while now)

https://www.apc.com/us/en/faqs/FA156586/
 
Last edited:

solderdude

Grand Contributor
Joined
Jul 21, 2018
Messages
15,891
Likes
35,912
Location
The Neitherlands
Yes, I noticed the option as well and the older SURT didn't have it. There are other new features as well such as 'green mode' where the generator is completely off and not synchronised and ready to go.

I had to reconfigure the remote access card to get it to work like the SURT version as well.
 

ta240

Major Contributor
Joined
Nov 7, 2019
Messages
1,360
Likes
2,656
Now, I did not plug in a drill or anything as I doubt audiophiles do that. :) I can try next time.

How about a dimmer switch with LED lights? I know, audiophiles don't use such evil things...
 
OP
amirm

amirm

Founder/Admin
Staff Member
CFO (Chief Fun Officer)
Joined
Feb 13, 2016
Messages
44,376
Likes
234,559
Location
Seattle Area
How about a dimmer switch with LED lights? I know, audiophiles don't use such evil things...
I have one of those on my workbench! On occasion when I see noise in measurements I turn it on and off but have yet to see any effect it has.
 

ta240

Major Contributor
Joined
Nov 7, 2019
Messages
1,360
Likes
2,656
I have one of those on my workbench! On occasion when I see noise in measurements I turn it on and off but have yet to see any effect it has.

When I had a noise harvester it would flash like crazy when I turned on a dimmer but the outlet that my audio plugs into shares the line with the dimmed light. Someday I'm going to put that outlet on its own breaker but in reality I don't think my equipment level needs that at this point.
 

GXAlan

Major Contributor
Forum Donor
Joined
Jan 15, 2020
Messages
3,869
Likes
5,955
When using a flat ribbon speaker cable as an interconnect, LED recessed ceiling lights impart a loud audible buzz.

The Noise Harvester does blink more when the LED lights are on but it doesn’t do anything for the problem.

Switching to shielded interconnect cables did.
 

solderdude

Grand Contributor
Joined
Jul 21, 2018
Messages
15,891
Likes
35,912
Location
The Neitherlands
One should never use not-shielded interlinks. No matter what the interwebs says.
 
Top Bottom