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Do you need AC Noise Filtering For Your Audio Devices?

I guess you could pay 500 on the Isotek, but as a retired communications tech for 30yrs we almost always used the Isobar
line of strips and outlets by Tripp Lite the Isobar Ultrablok blocks more rfi/emi than the 500 dollar one and is cheaper $45
and comes in 2 to 8 outlets I believe Isobar 4,6 or 8. We also used ferrite ring on DC lines to ant microwave phone and scada equip.
 
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Surge protection and filtering power strips are still common in the UK, but unless you spend a lot, they don't really do much for the smaller pops and clicks you can get on your internal wiring when anything with a motor turns on or off (or maybe any thing with reactance, more accurately). But they don't do any harm either.

In the UK, all new installations of fuse boxes normally include surge protection, but this is mostly about mains-borne spikes coming into the house from the external mains. It literally blows to protect your kit, and requires a new part to sort it out (best carry a spare, and you'll never need it!).

US viewers, note that the UK has mostly "ring mains" in houses (look it up), and that can make switching transients worse as there is less inherent damping.

Having said all that, I have very few things in the house that are affected. My stereo is utterly silent no matter what happens on the mains, but my guitar amp informs me (quietly) that my fridge or freezer is still working :)

Actually, mains protection strips could be a subject for review, in terms of Good, or Snake Oil if not already covered. I can imagine Amir et al twiddling a fridge thermostat up and down.....
 
It WOULD be interesting to see how much RFI filtering is offered by surge strips like the Tripp Lite products. I did not know that some "surge protector strips" also provide RF filtering.

ALSO it would be interesting to see how well they suppressed spikes and surges. This would require some way to generate controlled levels and frequencies of spikes... Amir would need something like=> THIS https://www.com-power.com/products/surge-generators/sgiec-645

I don't know if you could ever find some objective measure of audio improvement from these kind of simple RFI filters. And of course one would not want to connect an amplifier to a surge / spike generator to see if the amp blows up.... but it would be interesting to test a surge strip to see if they actually do help prevent the transmission to the load of bad power events that do sometimes occur.
 
I agree. I'm not as much interested in the RFI "filtering" for "objective audio improvements" so let's avoid that quicksand. As many have stated here and in several other threads, most of today's PSU filter most "line noise" from reaching into AV circuits so for me, it is not the priority. I am interested in real surge protections which are not MOV-based to protect my setups from premature failures.

WRT to power surges, we have quite a few informative YT vids showing things being zapped with various voltages. My long time surge protection favorites deploy "series-mode" protections (BrickWall, ZeroSurge, and SurgeX). I've recommended SurgeX units to friends and family for 20+ years and deploy them myself in my AV setups.

Below are a few demos and yes some are marketing-based. However, we cannot deny what they are showing WRT their designs. The ones where they connect in components and they fry them make their points. Some show the SurgeX units handling the 6K volt surges as well as what happens to often used MOVs.

SurgeX
> Will it blow? ->
> Will it blow2? ->
> WIll it blow3? ->
> Demo with MOVs ->
> Demo with MOVs (older) ->

As my brother learned last year when an "in the vicenty" lightening induced surge hit took out several appliances and security systems, several other things failed ~ 6 months later. This is happened twice to him in 10 years. He now has his AV setups and computer setups plugged into SurgeX SX-1120RT/1115RT which I picked up for him off eBay at a good price.

Why? Intense surges weaken onboard components... which hastens their failure many months after insurance may have settled your initial damages... good luck.

Full disclosure: I have no financial or other interest in SurgeX/ESP/AMETEK. Peace. Stay safe, stay alive.
 
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Mass Test plug in filters - A short update and view on the contenders


In my house I have serious grid noise that I have managed to solve with DC blockers (from ATL Audio according to my specifications) + Schaffner RF/EMI filters + Würth 150 kHz ferrites.
 
GB: Round #9; Fo-Felix AC Filter

GB: Round #9; Fo-Felix AC Filter

We're on round #9!!! 5x20mm fuse option added for Euro buyers Prices have increase some, but luckily it's minor So over the years people have asked about the old version, made by someone else. It's probably time for an updated one. This one is a bit different. You may notice it does not...
www.diyaudio.com www.diyaudio.com
Fo-Felix AC Filter.png
 
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freemansteve said:
Surge protection and filtering power strips are still common in the UK, but unless you spend a lot, they don't really do much for the smaller pops and clicks you can get on your internal wiring when anything with a motor turns on or off (or maybe any thing with reactance, more accurately). But they don't do any harm either.

In the UK, all new installations of fuse boxes normally include surge protection, but this is mostly about mains-borne spikes coming into the house from the external mains. It literally blows to protect your kit, and requires a new part to sort it out (best carry a spare, and you'll never need it!).

US viewers, note that the UK has mostly "ring mains" in houses (look it up), and that can make switching transients worse as there is less inherent damping.

Having said all that, I have very few things in the house that are affected. My stereo is utterly silent no matter what happens on the mains, but my guitar amp informs me (quietly) that my fridge or freezer is still working :)

Actually, mains protection strips could be a subject for review, in terms of Good, or Snake Oil if not already covered. I can imagine Amir et al twiddling a fridge thermostat up and down.....
Click to expand...
Yes, I agree. Not so much for audio improvement as to save equipment from bad surges, when you live in an area prone to them.
 
Talking about surges, years ago I have had a peak of 400 Vac at home (sparks in the street, the electric company had to come).

Thanks to the varistor of the first DC Blocker prototype, my second audio chain, in operation at the time, was protected. I just had to change the varistor.

DC-Blocker-prototype-varistor-burned.png


DC-blocker-varistor-fuse-ATL-maty-inside.jpg



Later I changed the EPCOS 18,000 uF with Mundorf MLGO 47,000 uF but this is other story.

Mundorf-MLGO-table.png
 
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maty said:
Talking about surges, years ago I have a peak of 400 Vac at home (sparks in the street, the electric company had to come).

Thanks to the varistor of the first DC Blocker prototype, my second audio chain, in operation at the time, was protected. I just had to change the varistor.

View attachment 226151

View attachment 226150
Click to expand...
I live near farms. At certain times of the year they put some odd things on the line, including nasty surges. The power company helped the situation a lot by installing power factor capacitors, which also tend to filter voltage surges and line harmonics.
 
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