No no no, i didn't take it that all. All great comments. Now you made me curious on what the best digital path may be.
I am able to play the same file with the Rpi and PC and learn that difference as well.
The Minisharc is being fed with a cheap supplied wallwart power. So its cheap on board regulation is probably not have the best power to work with. When I do my own DSP board I can do a much better job at PS. I just want to know what else I need to be careful with. Its sounds like a I2S signal path as far a possible is probably the less perilous path.
Measure it!
If you can hear a difference, you can measure it. How about measuring with and without the device in the path. To be audible, there would be something very obvious wrong. Some easily measurable distortion or noise or frequency response change. Without measuring, we will be left with endless speculation and no conclusion. Great for generating a long thread, but useless for solving the problem or learning anything.
If you can hear a difference, you can measure it. How about measuring with and without the device in the path. To be audible, there would be something very obvious wrong. Some easily measurable distortion or noise or frequency response change. Without measuring, we will be left with endless speculation and no conclusion. Great for generating a long thread, but useless for solving the problem or learning anything.
Some wallwarts tend to couple high frequency common mode noise into their DC output. Eventually, it can get coupled into differential mode noise at maybe around 1-2MHz, it depends. That can get into analog circuitry and dynamically shift bias levels if it gets demodulated in semiconductor junctions. The result can be audible distortion that doesn't show up very well on a typical audio FFT if it is quasi-nonstationary relative to the FFT acquisition timeframe.
Jitter is something I consider to be a tricky issue. It tends to have a sound that is different from other types of distortion. If you have a way to change jitter while listening, its possible to get better at recognizing its audible effects.
To be sure if audible problems occur, I use multiple independent trusted skilled listeners. If they can hear an issue with perceived sound quality, then I consider it a problem for my purposes.
Jitter is something I consider to be a tricky issue. It tends to have a sound that is different from other types of distortion. If you have a way to change jitter while listening, its possible to get better at recognizing its audible effects.
To be sure if audible problems occur, I use multiple independent trusted skilled listeners. If they can hear an issue with perceived sound quality, then I consider it a problem for my purposes.
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What?
More hypothesis and no data. This stuff is easy to measure, so measure it and present some evidence. I'm sure the folks that design and build the product you are disparaging would like to know what you find if it has any basis in reality. I spent several years designing very sophisticated filters to block noise from wall warts from messing up touch screens. Unlike optical digital audio, and shielded electrical digital audio interfaces, touch screens are very sensitive to common mode voltages. Bad wall warts had 40V p2p common mode voltage, but so what. Difficult to see how that will couple into the optical signal and make any audible difference. Again, super easy to measure, and show if there was some correlation to the audio. If listening tests are not carefully controlled, you can be lead to believe that $120 fuses sound better than the cheap ones.
More hypothesis and no data. This stuff is easy to measure, so measure it and present some evidence. I'm sure the folks that design and build the product you are disparaging would like to know what you find if it has any basis in reality. I spent several years designing very sophisticated filters to block noise from wall warts from messing up touch screens. Unlike optical digital audio, and shielded electrical digital audio interfaces, touch screens are very sensitive to common mode voltages. Bad wall warts had 40V p2p common mode voltage, but so what. Difficult to see how that will couple into the optical signal and make any audible difference. Again, super easy to measure, and show if there was some correlation to the audio. If listening tests are not carefully controlled, you can be lead to believe that $120 fuses sound better than the cheap ones.
Would an FFT of a 1khz or 10khz sine wave at the output of the DSP compared to a bypass be useful?
Sine waves or complex signals
An FFT of a sine wave could work. I could imagine capturing the input and output and subtracting them. Do it for music, or pink noise or whatever. See what the difference is. How large is it? It's digital, so we are talking about comparing two lists of numbers. Play the difference and listen to it compared to the signal. Seems like any engineer would start by get a measurement of the magnitude of this "SQ degradation".
An FFT of a sine wave could work. I could imagine capturing the input and output and subtracting them. Do it for music, or pink noise or whatever. See what the difference is. How large is it? It's digital, so we are talking about comparing two lists of numbers. Play the difference and listen to it compared to the signal. Seems like any engineer would start by get a measurement of the magnitude of this "SQ degradation".
Gym's closed, and I'm going cold turkey on Facebook
I didn't have a lot going on today. It seems that there are several rules to follow in generating a popular thread. 1. Don't be specific. That can lead to a quick resolution and then the thread is dead. 2. Use a catchy abbreviation "SQ". 3. Have the original post author ignore posts for a long while. 4. Make untestable or untested vague claims about hearing something. 5. Blurt a bunch of data sheet numbers 120 dB vs 140 dB. 6. Talk about maybe designing something better, without defining how you are going to measure "better" or ever addressing what an audible difference would even be.
I didn't have a lot going on today. It seems that there are several rules to follow in generating a popular thread. 1. Don't be specific. That can lead to a quick resolution and then the thread is dead. 2. Use a catchy abbreviation "SQ". 3. Have the original post author ignore posts for a long while. 4. Make untestable or untested vague claims about hearing something. 5. Blurt a bunch of data sheet numbers 120 dB vs 140 dB. 6. Talk about maybe designing something better, without defining how you are going to measure "better" or ever addressing what an audible difference would even be.
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Great for generating marketing ploy for boutique DAC business.
Well put!
If this post was directed at me I asked a general question, took advice on what possible measurements to take and I plan to follow through. You made useful contribution when you encouraged me to verify what I hear through a measurement. This last post of yours not so much.
There are pitfalls you have to be aware of on internet because it's not a well filtered domain. There are a lot of junk info floating around. olsond3 called out the usual red flag items that are common on audio forums. It would be to your advantage to build up a filter based on that.
I appreciate that. That is true for almost any thread on any forum on any subject on the internet. But it serves no one to make a post critiquing the content of an opening post by making a post totally devoid of useful content.
Unfortunately the problems of finding accurate information seem to be ubiquitous, not limited to forums. It can be hard to find reliable references to the "facts" stated and when posters are asked to provide references they very often don't as if all they really wanted to do was to get their view out there regardless of whether it has any merit.
As I'm most famous (in my own mind) for creating threads with 0 or 1 replies, this is good information -
Those in the "business" seem most adept, here's a prime example Global Feedback - A huge benefit for audio
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