Author Topic: The power conditioning thread  (Read 6001 times)

jb

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Re: The power conditioning thread
« Reply #30 on: May 12, 2017, 10:44:52 AM »
Attached is Jon Risch AC line filter circuit. This is a very well design low pass filter that will attenuate any conducted noise from 1MHz to 10 GHz effectively. you must choose a low series resistance inductor , minimum 0.03 Ohm and below. Please note for the capacitor voltage rating , try to choose 400 to 500V so you have margin of safety for the circuit.

http://links.dalrun.com/Electronics/Docs/Surge_Protection/files/AC%20Filter%20&%20Surge%20Suppresor.htm

« Last Edit: July 16, 2017, 05:23:12 PM by jb »

jb

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Re: The power conditioning thread
« Reply #31 on: May 12, 2017, 10:46:04 AM »
Jon Risch AC line filter frequency plot:

« Last Edit: July 16, 2017, 05:24:47 PM by jb »

sumotan

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Re: The power conditioning thread
« Reply #32 on: May 12, 2017, 03:15:27 PM »
Bravo JB

Wow it's been moons that Id seen this schema.
Are you able to simulate it with a 100 watt loading ?

jb

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Re: The power conditioning thread
« Reply #33 on: May 12, 2017, 04:05:02 PM »
I re-simulated with a 10A current source at 240V. The filter response is similar with only slight shift of the -3dB cut off frequency. This is a cheap and good AC line filter...

« Last Edit: July 16, 2017, 05:26:08 PM by jb »

sumotan

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Re: The power conditioning thread
« Reply #34 on: May 12, 2017, 04:48:35 PM »
Oldie but goodie JB
Strange when you load the filter
with a 100 watt light bulb you
hear immediate changes in SQ
as I recall more analog sounding
if I dare say. I believe this filter
will work well in SG given that
there's so much Ac garbage on
the line these days

Cheers

jb

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Re: The power conditioning thread
« Reply #35 on: May 12, 2017, 05:16:02 PM »
It could be due to impedance mismatch, as when I simulated with higher filter output impedance to cause a impedance mismatch... the frequency response is no longer a smooth low pass filter response and have high overshoot at -3dB cut off frequency point. See frequency plot.... so you have to experiment and see whether the filter response is as simulated if you have instrument to measure it. Also you will notice that the filter phase change is very sharp at the cut off frequency point... this is not good for audio sound! the phase change should be gradually!

By loading with 100W light bulb, you effectively lower the filter impedance as light bulb resistance should be very low...

« Last Edit: July 16, 2017, 05:26:38 PM by jb »

sumotan

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Re: The power conditioning thread
« Reply #36 on: May 12, 2017, 06:59:52 PM »
Someone over your end should build one to test
Jon Risch did mentioned clearly that it works
better when load with a 100 power resistor or
light bulb. But off course who would want to waste
silly electricity onto a resisitor when you could
light up the room with a bulb. Lol
Thks  for the heads up as well as reminding me
that I should get a scope. Give mine away when
I moved over here

Cheers

lucasng

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Re: The power conditioning thread
« Reply #37 on: May 12, 2017, 08:26:59 PM »
Hi Jb,

Yes sure. Thanks for reminding me !

Here are some photos of the mentioned conditioner.




Note;
You'll be able to customise the type of duplex receptacles used as well as the internal cabling. By default we are using the Furutech alpha-OCC cable/Neotech OCC/Western Electric. The balanced toroidal was customed made for us. Digital treatment was done for a single column of duplex receptacles, by doing so, this eliminated graininess and harshness of the digital domain, making the overall sound more analog. Attention was also paid to ensuring the toroidal is well damped from external vibrations. This was accomplished both internally and externally(well machined chassis).

For the unit that will be used for comparisons, its fitted with dual furutech ncf receptacles, providing great sense of rhythm and dynamics. We welcome owners with power conditioners to have a go with this. It will definitely not disappoint.

Furutech ncf receptacles;
http://www.furutech.com/2015/11/18/12066/

Those keen for a non-obligation trial, kindly drop me a text at
9 one one 5 2 four 8 7.

For more information on photos of various comparisons, do drop me a whatsapp message.

Thanks for reading !

sumotan

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Re: The power conditioning thread
« Reply #38 on: May 13, 2017, 12:00:04 AM »
You mean someone has made the Risch filter for sale ?
Btw I don't get it why everyone is fixated on toriods,
only tried once on my project & immediately went
back to EI . Sq wise EI sounds better & off recent
yrs it's been proven the toriods are a no no due
to its poor rejection to noise. Haizzz looks like its
back to the pen is mightier then the sword thingy
Think the better solution is 1 Risch filter per
equipment. Caps that I used were Wima FKP

Cheers

jb

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Re: The power conditioning thread
« Reply #39 on: May 14, 2017, 04:24:24 PM »
I think what Lucas shown below is a balance transformer design with some noise filtering circuit and not Risch filter.

But I think there are actual commerical type of similar "Risch" filter that are manufacturing by big cooperation that we can try it for our audio application, I believe you will get similar performance as Risch filter...as is similar circuit and design...
as shown below....some built into IEC connector which is very convient. Of course all this can only use for low current application like CDP, DAC, pre-amp type..


« Last Edit: May 14, 2017, 04:35:44 PM by jb »

jb

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Re: The power conditioning thread
« Reply #40 on: May 14, 2017, 04:37:11 PM »
actual AC line filter sell by R&S... as attached
Also the advantage of using common mode choke instead of two inductors  have better common mode noise rejection.
« Last Edit: May 14, 2017, 04:39:13 PM by jb »

jb

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Re: The power conditioning thread
« Reply #41 on: May 14, 2017, 04:47:07 PM »
The AC noise filter only cost US$3 that you can order from Aliexpress to try it out... see attached info

sumotan

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Re: The power conditioning thread
« Reply #42 on: May 14, 2017, 11:33:55 PM »
Tried those long ago JB. Didn't like what I heard.
Like all tweaks I believe type of caps use in the
filter affects the SQ as well. Re chokes be it single
or common mode varieties, I always stay away from
ferrite cores. In my experience it the away life &
sounds dark. For high current powder iron is best
due to ut low saturation point but they're so hard
to come by. I've build a new AB amp which is
powered by Hypex smps. Well compared to the
old amp which is the same but with linear supplies,
I think the days of big trans & large filter caps
is coming to an end.

jb

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Re: The power conditioning thread
« Reply #43 on: May 15, 2017, 10:29:42 AM »
No harm trying just for $3, and can modified the capacitors or inductors to the sound you like... yes , "powered iron cores can typically handle more RF power without saturation than same size ferrite core. Ferrite if driven with large amount of RF power tends to retain its magnetism permanently and this ruin the core by changing its permeability permanently." Actually Aliexpress also sell the powered iron core for about US$2.5 per piece that we can buy and DIY the coil wounding to try out...


https://www.aliexpress.com/item/T200-2-high-frequency-of-carbonyl-iron-powder-core/32271031808.html?spm=2114.01010208.3.1.MloIu1&ws_ab_test=searchweb0_0,searchweb201602_4_10152_10065_10151_10068_436_10136_10137_10157_10060_10138_10155_10062_10156_10154_10056_10055_10054_10059_100032_100033_100031_10099_10103_10102_10096_10147_10052_10053_10050_10107_10142_10051_10084_10083_10080_10082_10081_10110_10175_10111_10112_10113_10114_10181_10183_10182_10185_10078_10079_10073_10123,searchweb201603_9,ppcSwitch_5&btsid=3d2e2f04-1af4-4aee-88fc-8407532ae934&algo_expid=6ddb0ddc-0d3f-4b45-b5ef-34c02b5d14dc-
0&algo_pvid=6ddb0ddc-0d3f-4b45-b5ef-34c02b5d14dc

Another place that you can get powered iron core is amidon corp in USA that makes good quality products, also the cost of core is cheaper, may be have to pay higher postage fee.

http://www.amidoncorp.com/iron-powder-toroids/
« Last Edit: May 15, 2017, 05:20:43 PM by jb »

jb

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Re: The power conditioning thread
« Reply #44 on: May 15, 2017, 10:34:00 AM »
For switching power supply design - Hypex smps, I feel you will add more noise to the audio system. If you can think of all transistors and resistors has KTB noise, if you add more of this device to your system, the total system ham & noise spec of amp will be worst off.