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foobar2000 modular freeware audioplayer for Windows developed by Peter Pawłowski

pozz

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Would someone mind explaining the effects of the window function options?

1567646045577.png
 

Zog

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AnalogSteph

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Would someone mind explaining the effects of the window function options?

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This is needed so your spectrum doesn't look like crap.

In order to run it through a FFT analysis, the audio stream has to be chopped up into pieces of finite length. With no window function, this equals multiplication with a rect function in time domain, or convolution with a sinc function in frequency domain. As a result, any pure sine signal (theoretically a hair-thin needle in the spectrum) gains lots of unwanted side lobes that aren't actually there. In more complex signals, these tend to overlap and cover weaker components nearby.

The various window functions are different ways of rounding off the corners, so to speak. They vary in algorithms, computational complexity and how well they reduce the effect. (You are never going to get rid of it entirely, as any window of finite length invariably results in some spectrum spread - think Heisenberg's unsharpness relation, but in time vs. frequency.) One of RMAA's claims to fame at the time was usage of a Kaiser-Bessel window, which remains one of the best.
 

pozz

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This is needed so your spectrum doesn't look like crap.

In order to run it through a FFT analysis, the audio stream has to be chopped up into pieces of finite length. With no window function, this equals multiplication with a rect function in time domain, or convolution with a sinc function in frequency domain. As a result, any pure sine signal (theoretically a hair-thin needle in the spectrum) gains lots of unwanted side lobes that aren't actually there. In more complex signals, these tend to overlap and cover weaker components nearby.

The various window functions are different ways of rounding off the corners, so to speak. They vary in algorithms, computational complexity and how well they reduce the effect. (You are never going to get rid of it entirely, as any window of finite length invariably results in some spectrum spread - think Heisenberg's unsharpness relation, but in time vs. frequency.) One of RMAA's claims to fame at the time was usage of a Kaiser-Bessel window, which remains one of the best.
Thanks. Of the available functions, is there one to consider over the others?
 

Zog

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Tool, thanks and also respect. Another thanks for the help. The Enhanced Spectrum Analyzer has had positive impact. It looks cool in what was a mundane interface, and is a bit of fun to play with.
 

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Tool, thanks and also respect. Another thanks for the help. The Enhanced Spectrum Analyzer has had positive impact. It looks cool in what was a mundane interface, and is a bit of fun to play with.

And i'm really sorry for my response earlier I didn't want to be rude or anything. I've got problem with PC though so i'm trying to speak my mind. (not always accurate and polite):), glad it works for you.
 

Tool

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Tool, thanks and also respect. Another thanks for the help. The Enhanced Spectrum Analyzer has had positive impact. It looks cool in what was a mundane interface, and is a bit of fun to play with.

Oh and i'm offended of comparing me to Kevin Kline (avg Actor);)
 

MediumRare

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I enjoyed MusicBee for Windows (especially the interface) but have found I far prefer the sound of Apple via USB to my Musical Fidelity V-90 DAC using Audirvana. Sorry for hijacking this thread - but is there any review of the audio quality of different music players?
 

pkane

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Thanks. Of the available functions, is there one to consider over the others?

Different windows can have a different effect on amplitude or frequency precision and resolution of spectrum. A good overall function is Hanning. There are better ones available but they are more complex and require more computation.
 

MediumRare

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Unless they're doing some DSP, they should sound the same as it's their job to decode various formats properly and dump them to PCM once done.
I agree, but as we see with Windows at least, there's a lot that can get in-between the reading of the bits and the sending of the bits. If not, would be a great topic for a head-to-read fact checking review.
 

Ron Texas

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Works fine for me on WASAPI Event for all bitrates/frequencies I've thrown at it, on multiple different PCs. My Topping DX7 confirms the occasional HiRes track as being sent bit-perfect via its own display.

I just wish someone would write up a Google Home Assistant plugin for us so we could talk to FB2K.
I've had the same problem with WASAPI event and native UAC2. The workaround is to install a manufacturer's driver which bypasses the Windows driver, don't use USB class 2 or use push, which works nicely.

There might be something different about your DAC.
 

BillG

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I agree, but as we see with Windows at least, there's a lot that can get in-between the reading of the bits and the sending of the bits. If not, would be a great topic for a head-to-read fact checking review.

That why one uses WASAPI Exclusive and locks the bit depth and rate on a media player. Regardless, I never had an audible problem with Windows resampling. So I really couldn't care less about what it does in between.
 

pkane

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That why one uses WASAPI Exclusive and locks the bit depth and rate on a media player. Regardless, I never had an audible problem with Windows resampling. So I really couldn't care less about what it does in between.

I've had some issues with Windows resampler, although I can't say this was audible (on Windows 8). Here's a chirp downsampled by Windows from 96kHz to 44.1kHz:
1568773745301.png


All those dark diagonal lines are aliases and folded aliases created by Windows resampler. All low in magnitude, but looks a bit nasty, doesn't it?

Here's an improved one, had to write the resampler myself:
1568774018601.png
 
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