EMC and signal integrity are two sides of the same coin...signal integrity is EMC local to the PCB, EMC is the susceptibility to external interference and stopping the design in question radiating noise, design takes both into consideration.
If a ferrite sound "ear bleeding nasty" then I imagine its effects should show up quite clearly with measurement.
If a ferrite sound "ear bleeding nasty" then I imagine its effects should show up quite clearly with measurement.
My CD player was a $5000 unit originally. The man who designed it said it spec'd the best because he had so much room to work with. One of the reasons he doesn't have any ferrites in the subsequent models is due to space restrictions. So no you guys are utterly wrong. Not every EE designs with a bare minimum attitude. This is a great example where he made it the best he thought he could, sparing nothing, but ended up not bothering to sell the unit at all really just due to the fact that it's profile is bigger than most equipment including many amplifiers. I believe it was pulled from the market in less than 2 months or something of that sort.
All but one ferrite was not inside the PSU shield. They were not intentional to have anything to do with radiation etc, since it's a very low radiation device to begin with. The same DAC chip and parts have been used in thousands of players that don't feature the ferrites.
The thought of "guessing" it's better is utterly foolish. If I had to guess as to whether the sound was better, I'd probably just put it back in to keep it stock. It's not a guess; it's not like someone brushing your butt in a packed nightclub, it's like someone grabbing so hard it lifts your foot off the ground. It's not a subtle distinction.
Max I'm really glad you're around. The audio world needs people bold enough to try something once in awhile instead of just limiting themselves to their trained imagination.
All but one ferrite was not inside the PSU shield. They were not intentional to have anything to do with radiation etc, since it's a very low radiation device to begin with. The same DAC chip and parts have been used in thousands of players that don't feature the ferrites.
The thought of "guessing" it's better is utterly foolish. If I had to guess as to whether the sound was better, I'd probably just put it back in to keep it stock. It's not a guess; it's not like someone brushing your butt in a packed nightclub, it's like someone grabbing so hard it lifts your foot off the ground. It's not a subtle distinction.
Max I'm really glad you're around. The audio world needs people bold enough to try something once in awhile instead of just limiting themselves to their trained imagination.
Well, no, we're not wrong. What you're describing should be measurable. Stating that it's foolish to be doubtful and continuing to bloviate about it isn't going to satisfy anyone's curiosity or answer any questions.
It would probably be easily measured with a high res DAC being used as an instrument. I don't have that ability (yet). It won't be of value with an O-scope to try.
I'm baffled that people here often love to tell others their personal experience with one particular circumstance is wrong. Go have your own experience instead of typing about mine all day. I posted to encourage people to experiment, to physical try things; not to have people speculate whether I'm at a level of institutionable delusion.
Our distinctions what what is "good" is a bit crude. As Speedskater said, sometimes people prefer poorer measurements for sound quality to their ear, not a graph. However, it's abundantly clear even if this happened, simultaneously the vast increase of information and timbre are not represented within the effect. There may be a host of other things happening here. I get very similar results when I add filtration of different types to all equipment. That's right, when I calculable and measurably greatly increase filtration the end result is only akin to what I've got with removing these ferrites in THIS unit.
I'm baffled that people here often love to tell others their personal experience with one particular circumstance is wrong. Go have your own experience instead of typing about mine all day. I posted to encourage people to experiment, to physical try things; not to have people speculate whether I'm at a level of institutionable delusion.
Our distinctions what what is "good" is a bit crude. As Speedskater said, sometimes people prefer poorer measurements for sound quality to their ear, not a graph. However, it's abundantly clear even if this happened, simultaneously the vast increase of information and timbre are not represented within the effect. There may be a host of other things happening here. I get very similar results when I add filtration of different types to all equipment. That's right, when I calculable and measurably greatly increase filtration the end result is only akin to what I've got with removing these ferrites in THIS unit.
I'm not trying to say anyone is wrong, honestly. I'm just of the opinion that, while interesting to read occasionally, it'd be better to accompany anecdotal experiences with something that lends itself to being useful to other people.
We've probably got enough people reading this thread which could easily amount to millions of dollars worth of warrantied equipment, with what could possibly be hundreds of ferrite chokes. The expectation here is that when a large number of people might potentially be looking at a warranty destroying modification to their gear, that enough respect for those individuals be demonstrated by some type of repeatable, measurable information exchange...you know, the kinda stuff the the internet should be used for.
"I'm tapping my feet harder now that I did it." can't and shouldn't be taken with any kind of gravitas or scientific value, no matter how poetic it sounds. Lecturing is great, but if we don't hit a textbook at some point, especially when we're discussing electronics, the class is pretty much devoid of substance - and at the same time can devolve into outright harmful disinformation if there's never a call for concrete evidence.
While on the subject of ferrite beads, I'm trying to get an answer as to how much ripple such beads can sustain. I was thinking of using some in a linear PSU to improve high frequency noise rejection. I know they're typically used in DC circuits to filter HF noise in the inbound Vs for critical components. I tried to get some help from Wurth Electronics support team but no reesponse thus far. Any guidance from those who know them better would be appreciated.
So we just have to believe you on your word.
Your not talking to little kids here, who believe anything that's being said to them.
And your even being insulting to yourself for not doing proper testing.
If you mean how much power they can handle then I would suggest that, if they get hot, that is the least of your worries. Their purpose is to increase the impedance at high frequencies, so any grot on the line decides to take a different path to ground. Whilst there may be some, I cannot think of a case where a bead (not wound as an inductor) would have any appreciable power dissipation.
If you just want to know about attenuation then there are plenty of documents on that which google can find for you.
If you just want to know about attenuation then there are plenty of documents on that which google can find for you.
I'm fine re attenuation (vs freq) and also current rating which are provided in datasheets. But because they are typically used to 'clean' regulated Vs in a digital circuit I've not been able to find much info on their ability to withstand ripple at lower frequencies and whether placement in a linear PSU, after the rectifier and between filter caps i.e. in series with filter resistors, would cause problems e.g. get too hot or worse. Presumably if they offer little impedance at these frequencies they can handle it (?) but trying to get confirmation of such is eluding me. I will persevere with Wurth but wanted to see if anyone here knew (given the discussion of beads).
http://katalog.we-online.com/pbs/datasheet/74271318.pdf
Look at the data!
Impedance is only shown for 1MHz+, with the trend easily going to near zero at 100Hz.
Entirely intuitive!
Cliff
Look at the data!
Impedance is only shown for 1MHz+, with the trend easily going to near zero at 100Hz.
Entirely intuitive!
Cliff
Thanks Cliff. So follow my intuition and don't sweat regarding any other issues...
(It would seem odd to me that they don't seem to be deployed more often in PSUs but then I guess that's the debate you all are having...)
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Depends on what area of electronics, and the noise requirements of the circuitry...
Do mil/aero where higher EMC and noise attenuation is required and there are plenty, as do many sensitive ADC/DAC designs where they are often used to form power islands for a single device or group of devices.
Do mil/aero where higher EMC and noise attenuation is required and there are plenty, as do many sensitive ADC/DAC designs where they are often used to form power islands for a single device or group of devices.
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