Schaffner is a reputable product, it is intended to attenuate conducted mains bourne High Frequency noise in both directions. You can see the attenuation curves for symetrical and asymetrical attenuation compared to CISPR recommendations (curves A & B on each graph, and three illustrations for 1-3 Amp, 6-10 Amp and 12 - 15 Amp inlet sockets with different values of C and R indicated in their schematic.
This may or may not make a lot of sense to you but your equipment may be susceptible to some noise conducted through the power lines into as well as emitted by your equipment through the power lines to other equipment.
Whether this may or may not make an audible difference is debatable and you can only confirm this by listening. That it makes a measurable difference is and compliance with the EMC compatibility requirement for Europe is essential.
I have heard the device in an up-market audio distributor, the system used two Mark Levison amplifiers that stood another meter tall, B&W 800 speakers, a CD player that cost as much as my house and one of these power packs. The sound room was of extreme standard and no cost was spared, and the equipment sounded phenomenal playing Diana Krall.
At home I decided to experiment with two 100 Ah deep cycle batteries and a 2.4KVA low distortion sine wave inverter. I do not have the sound room or equipment that they used, but the audible effect was phenomenal in comparison to running fron raw mains. I have not removed the system since and only added a decent 24V battery charger that is turned off when listening to music.
I would recommend using an independent and capable low distortion mains supply. Mine is over sized for what I need but I happen to have a demonstration unit available at work and decided to buy it. I do not recommend the inverter types that chops a high voltage stepped up DC into a sort of sine wave, it must be a proper low distortion sine-wave inverter that uses a big transformer.
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That IEC inlet is useless.
The simplest, easy, power conditioner I know, that works is known as the Felix. I can tell you that the Coilcraft and JW 17a CMC's are great. The Coilcraft over differential mode too. All of them help keep your system clean from itself. Basically it's one on those CMC's, with X caps on either side. People often do .1uf .47uf 1uf CMC 1uf .47uf .1uf. X caps are parralel, by definition. When you search parts site use X1 or X2 in search bar.
It can big and more complicated. But also it becomes more dangerous, so it's best to be experienced.
Coilcraft Combination Line Filter Choke
8120-RC J.W. Miller | Mouser
Use good sockets from Leviton, Hubble, or Bryant; prefered hospitol grade. Expensive audio ones are good too. All of them allow you to break off the tab near compression screws for socket isolation so you can put a Felix on each.
The simplest, easy, power conditioner I know, that works is known as the Felix. I can tell you that the Coilcraft and JW 17a CMC's are great. The Coilcraft over differential mode too. All of them help keep your system clean from itself. Basically it's one on those CMC's, with X caps on either side. People often do .1uf .47uf 1uf CMC 1uf .47uf .1uf. X caps are parralel, by definition. When you search parts site use X1 or X2 in search bar.
It can big and more complicated. But also it becomes more dangerous, so it's best to be experienced.
Coilcraft Combination Line Filter Choke
8120-RC J.W. Miller | Mouser
Use good sockets from Leviton, Hubble, or Bryant; prefered hospitol grade. Expensive audio ones are good too. All of them allow you to break off the tab near compression screws for socket isolation so you can put a Felix on each.
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Are you referring to link in post16?
Schaffner datasheet is probably very reliable.
And it states
typical applications: medical devices (MDD).
Without knowing exactly what you are filtering (spectral analysis) it is kind of a crap shoot with the filters. For a couple of bucks you won't get to hurt with these from Apex jr but no telling what you got until you get it.
http://www.apexjr.com/images/APEXJREMIFILTER1.jpg
Bill
http://www.apexjr.com/images/APEXJREMIFILTER1.jpg
Bill
Useless.
Trust me on this... They're a stupid design. First they have Y capacitors on the out side, so RF has no way out of your stereo, but through other devices/speakers because of the inductor on the safety ground. I could say more, but what for? No one in the industry uses those for reasons. Did you look at their resistance? 1000k ? Good lord, I get fidgity when looking at anything that might touch upwards of 2ohms, or even 1 ohm. I doubt I need to discuss why. Also don't think the 1000k resistor is the bleed resistor, it isn't, because you could cook eggs on it, in that setup.
It's best to cover a wide range of frequencies. Those CMC's I linked to, filter in a particular range but also their reactance is high enough in the right ranges that RF will go straight to the capacitors. You CAN hear the difference in a significant way. In fact by chosing better CMC's, better sized, you get more effective conditioning than Audience Adept units that only use the larger CMC's that don't offer any differential mode nosie filtration. They also don't have any caps prior to the CMC. They have been thuroughly tested and reviewed, people love them. The only reason they fell out of some popularity is because companies offer better, bigger, units commercially now and there are no PCB's anymore.
If your conditioning doesn't make you go, "damn, that's nice" immediately, you're doing it wrong, guranteed. Most commercial units these days are at that level, but even then some are better than others and you can't always tell immediately because the human ear isn't good at understanding the differences because they are the differences we spend zero time on since we're generally unaware they exist. When I lend one of my power conditioner - that I make - to someone I tell them to listen for at least two weeks. And by the end when they pull it they can tell that their other unit wasn't as good, even though first impression was close. "Magic" if you will, but it isn't.
Source noise variance is good, it means the noise will see filter caps as being a better current path. That's why capacitance increases is favored, but there are a lot of safety concerns. The amount I mentioned for the Felix is minimal, and as safe as wiring an AC recepticle to begin with. Others look towards transformers, which have only recently become worth using for whatever reason. I've never liked the sound, and the cost can be prohibitive for a DIY person. I'm inexperienced with regenerators but I'd bet money they won't cut the muster on some very good gear. There's a few reasons for that, depending on the gear, but that's not something I want to discuss. I could go on and on. Waste time and money on garbage if you want.
They are the industry standard EMI filter design.
Since there is capacitance on both sides of the inductors, differential mode RF is shunted. But keeping RF *inside* a device is partly what EMI filters are intended for.
Ever looked inside a CD player?
You seem to be confusing series resistance with shunt resistance. If you actually LOOK at the diagram, the resistor is indeed a bleeder. It is 1000k, or 1Meg, which will dissipate 57mW on 240V, leaving you with a rather cold egg.
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Oh right, 1000k 1meg, was thinking 1k.
Anyway it's still trash for audio. And it's not going to shunt RF very well. Not when there are other paths.
I haven't seen them in any good CD players.
It's trash for audiophile grade playback. I don't care who's standard it happens to be. You can hear the difference. I use to put junk like that in equipment, never able to really tell the difference. But now the wiser I have real conditioning.
Anyway it's still trash for audio. And it's not going to shunt RF very well. Not when there are other paths.
I haven't seen them in any good CD players.
It's trash for audiophile grade playback. I don't care who's standard it happens to be. You can hear the difference. I use to put junk like that in equipment, never able to really tell the difference. But now the wiser I have real conditioning.
That's not entirely surprising, as EMI filters are designed to work at hundreds of kilohertz to megahertz. Not the sort of frequencies that are easily heard, unless they're having some truly dire intermodulation effects.
(I think a lot of beginners think those filters are supposed to turn the mains supply into a nice pure sine wave, which is NOT what they are for.)
How exactly?
They correspond to certain norms and regulations for safety reasons and to achieve the required EMI suppression.
There is a simple explanation for it. They are EMI filters, not RF diverters. They have to filter both ways, not dump the stereo's waste somewhere else.
It is the bleeder resistor as required by norms and regulations. The value is dictated by those as well. The resistor must be small enough to discharge the capacitors fast enough after power down and big enough to limit the leakage current during operation to a safe value. That does not leave much margin for different values.
I wonder what you could cook on 1 or 2 Ohm resistors. Oh, sorry, you'll cook nothing, because the resistors will melt as fast as the fuses, both hopefully before anything else starts to burn.
Pacific blue, I happened to see that it's indeed 1 meg, I was thinking 1k. Please, spare me the redundancy of repeating my error.
50w resistors can get off enough and stay at temp to cook an egg btw.
RF is a serious problem in a stereo given all the long wires running everywhere. Phono... etc
Number 1 mistake in understanding power conditioning and noise, is the assumption is if there's noise in your system you can hear it being audible, or that only the audible ranges affect anything. Sorry but that's not how things work. That's a nice simple thought, but here's the thing... 99% of the time you're hearing the effects the noise has on the stereo, not the noise itself. You don't know what it is you're hearing the effect of until it's gone. It takes a lot of listening to stereos without it, to understand when it's there. Even the best ears can be fooled, even when they're somewhat use to it. Anyways I think I'm done with this topic. I want to help, I like the DIY community, but at some point I guess you have to accept the difference between certain levels DIY is willing to attain, and commercial levels. I deal with the ladder, and so long as you're all happy with your stereos I guess everything is fine.
50w resistors can get off enough and stay at temp to cook an egg btw.
RF is a serious problem in a stereo given all the long wires running everywhere. Phono... etc
Number 1 mistake in understanding power conditioning and noise, is the assumption is if there's noise in your system you can hear it being audible, or that only the audible ranges affect anything. Sorry but that's not how things work. That's a nice simple thought, but here's the thing... 99% of the time you're hearing the effects the noise has on the stereo, not the noise itself. You don't know what it is you're hearing the effect of until it's gone. It takes a lot of listening to stereos without it, to understand when it's there. Even the best ears can be fooled, even when they're somewhat use to it. Anyways I think I'm done with this topic. I want to help, I like the DIY community, but at some point I guess you have to accept the difference between certain levels DIY is willing to attain, and commercial levels. I deal with the ladder, and so long as you're all happy with your stereos I guess everything is fine.
I can Concur on this , we have a few philes in the group that have done the same to good results ...
Hi PacificBlue, when I say remarkable then you must understand that it generates a pure low distortion sine wave at 50 Hz as well as being regulated around 230VAC.
There is no link-up between the mains utility, the neighbors washing machine, you wife's hairdryer and all the rubbish sitting on your local grid generating all sorts of rubbish (mostly in the audio band) that can pass through your equipment mains transformer and into the signal patch.
There is also no bad wiring connections between your equipment and the distribution board, the distribution board and all your neighbors connected to the same mini-sub. That is the difference and it is VERY audible.
Besides that, there is no reference to earth thus hum is minimized. Thus there is no Live and Neutral and all your sound equipment is fed from the same supply and is star connected.
This is the closest that you will get running your system directly from a virtually noiseless supply of batteries.
British Gas/Scottish Gas/Scottish Gas Board Control gear ran from a motor generator with flywheel in between.
The back up in case of motor or generator failure was the mains supply.
The output was phase locked to the mains frequency and feedback adjusted the motor speed.
This removed all mains borne interference from the Control gear supply.
The equipment hut had a carbon filament incandescent bulb outside so that everyone knew the generator is/was working.
The back up in case of motor or generator failure was the mains supply.
The output was phase locked to the mains frequency and feedback adjusted the motor speed.
This removed all mains borne interference from the Control gear supply.
The equipment hut had a carbon filament incandescent bulb outside so that everyone knew the generator is/was working.
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