Actually these days I am seeing 50,000 hertz bandwidth for the -3 dB point with active filtering. Do-able with current technology and in unpublished ABX tests (Might be published soon though!) shows a difference.
That peak looks like those you get from not decoupling voltage references and regulators properly. Just compare the 2 pictures. I think I have published my pic already, but could not find the post.
regards, Gerhard
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Surely the garbage being talked about is generally common mode and there are plenty of well proven techniques for dealing with that? Or am I missing something?
I would try, R,C and lossy ferrite bead for the very HF. No air core inductors. Resonating caps would require some damping resistance.
Ferrites don't saturate at lier level signals and K Ohm resistance loads - they really are fantastic devices. And, like myrtle block cable lifters, they are completely inaudible despite what the Oracle of Boulder aka the Sandman, has to say on the subject.
I know, drives everyone screaming out of the room with their hands over their ears. Hysterical exaggeration seems to be required in all these listening impressions.
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^ I can't even walk into a room with those ferrite beads on DVI/HDMI cables. I can feel them from outside, their lossy magnetic-ness haunting me. 😉
That could be a possibility. Or noise shaping, perhaps. But everyone ought to look at what is coming and going above the music signal itself. Esp as the amps can and will try to amplify it. In test reviews, a filter is often at 30KHz (AP). You only get good data that way but not realistic, practical data. Esp as a system of components in a mixed signal (home) environment. A few years ago here I also showed some spectrums of freq put onto the ac power lines due to different products on the ac line... like a computer or lamp dimmer or TV/video monitor, etc. It's Nasty.
THx-RNMarsh
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That could be a possibility. Or from noise shaping, perhaps. But everyone ought to look at what is coming and going above the music signal itself. Esp as the amps can and will try to amplify it. In test reviews, a filter is often at 30KHz (AP). You only get good comparison data that way but not realistic, practical data. Esp as a system of components in a mixed signal (home) environment. A few years ago here I also showed some spectrum's of freq picked up on the ac power lines due to different products on the ac line... like a computer or lamp dimmer or TV/video monitor, etc. It's Nasty.
THx-RNMarsh
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IME ferrites do clean HF junk, BUT they also add a fatiguing and unnatural 'sharpness' to the overall sound.
Dan.
John,
At audio frequencies and up to 1-2 MHz, lossy ferrite SMD's are almost entirely resistive at very low single digit Ohms. If you are using beads over device leads, the DC and LF resistance contribution is zero. The real work of ferrites is done at 5-10 MHZ and higher.
You will not hear anything at audio other than a significant reduction in HF ( i.e MHz) demodulated garbage on your system. I'd take ferrites over BQP's any day. And at a few pennies, they are a real bargain.
See the Murata website for more details.
Could it be that the HF junk was adding a soothing and unnatural smudginess to the sound, which you miss when it has been removed?Max Headroom said:
Ferrites do, of course, have to be used with care. Externally they can be used to get rid of common-mode junk e.g. on speaker leads. They don't touch the differential mode audio signal. When used on a single wire, so subject to the audio signal, you need to choose the right ferrite.
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Sure we all agree on this as theory and practical application.
Yes, I do hear reduction in garbage/demodulated garbage.
I also hear an injection of a signature new sound that changes according to the ferrite example.
BQP gives a 'cleaning' but adds a signature of its own.
Yes much informative stuff....thanks for the pointer to revisit.
Basics of noise countermeasures [Lesson 8] Ferrite Cores
That return energy is not linear and I find that such ferrites do affect/effect baseband audio.
Yes, HF junk can add a dithering/masking of sorts.
And No, I don't miss that extra layer of modulation.
Could you elaborate please.
Dan.
You also get ferrite bead devices, where the component lead passes through the ferrite core, also available with multiple leads for common mode purposes... Used extensively with caps to form pi or t filters often on inputs to keep HF noise out...
The difference between ferrite beads and BQPs though is reality, on is based on reality on is based on BS.....
The difference between ferrite beads and BQPs though is reality, on is based on reality on is based on BS.....
Yes, I am well familiar with such devices/systems.
The ad copy might be BS.... could be the maker does not fully understand his creation.
Either way I find that ferrites and BQP (and others) affect/effect baseband audio and I think in a way not fully attributable to HF/RF attenuation/absorption.
Dan.
Sorry but have to disagree on BQP, common how can he not understand it.... stretching the imagination somewhat....
Regarding ferrites I don't see fears of it affecting other analogue signals (or audio) in other walks of life, strange, but then they don't use BQPs, even stranger!!!😱
Regarding ferrites I don't see fears of it affecting other analogue signals (or audio) in other walks of life, strange, but then they don't use BQPs, even stranger!!!😱
If you put an audio current (i.e. a single wire, not a signal and return pair) through a ferrite then it is conceivable that the non-linear nature of the ferrite could reflect back on the signal. This would mean that the circuit was low impedance and the ferrite has high permeability. This could be the case if you were using the ferrite as an inductor to stop low frequency RF. Bad use of ferrite! To stop low freq RF you need a choke, which either uses ferrite with a good airgap or a dust iron core. To stop high freq RF you can use a lower permeability but higher loss ferrite. As always in engineering, you need to read and understand the datasheets and understand exactly what you are trying to achieve. Simply slapping on a ferrite to an existing circuit may cause problems. That doesn't mean that ferrite is bad for audio; just that poor engineering is bad for audio.Max Headroom said:
You can, however, simply slap a ferrite on a signal and return pair as the audio signal seen by the ferrite is zero.
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