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You're right.
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General Audio / Re: Album Art Downloader XUI
Last post by AlexVallat -
Yeah, they had changed their json format, then after I updated the script, they changed it back again. Weird. Anyway, I've uploaded a script that should handle both forms now. Hopefully that should stop it breaking for a while.
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If there is possibility for a new codec in future that will be available for internet community that will be Ghost (or whatever it will be called). https://people.xiph.org/~xiphmont/demo/ghost/demo.html

Ghost can improve quality comparing to Opus more than considerably as it can use higher latencies (100-200ms) and some additional complexity. Today ARM chips  can decode at least 2x-4x complexity of Opus without dropping smartphone's battery life.
OK, so when it uses higher latencies, it's meant just for unicast streaming, etc.? Opus was designed to be a low-latency codec for VoIP, etc. that just happened to be good all round.

So Ghost will not replace Opus, merely it will be the "true" replacement for Vorbis, I take it?
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Internet isn't a viable option for patented formats anymore.
Google tries to get rid of AAC in Youtube (still supported in MS and Apple browsers )and pushes Opus. Spotify uses Vorbis and they can't afford a patented format. WhatsApp uses Opus. Netflix uses patent free formats for mobile clients as well. 

MPEG Surround is a standard since 2007 (10 years ago! ) and its presence is null in internet community.
The same goes for xHE-AAC. Something is telling me (and I don't know what is it  O:) ) the same will go for a latest standard 3DA which improves xHE-AAC quality furthermore.

If there is possibility for a new codec in future that will be available for internet community that will be Ghost (or whatever it will be called).  https://people.xiph.org/~xiphmont/demo/ghost/demo.html

Ghost can improve quality  comparing to Opus more than considerably as it can use higher latencies (100-200ms) and some additional complexity. Today ARM chips  can decode at least 2x-4x complexity of Opus without dropping smartphone's battery life.

PS. BTW  xHE-AAC's sweet spot is 24-32 kbps stereo. It's slightly better than HE-AAC at  >=48kbp bitrates. 
Chances that xHE-AAC will be any better than Opus at >=48 kbps are zero.

PS2. There is also a new format AC4 from Dolby. Dolby has acquired Coding Technologies (creators of SBR and Parametric Stereo). AC4 is similar to xHE-AAC (if not better)
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I don't know if what you want is a spectrogram, if you do, I'd suggest having a look at http://www.baudline.com/
It's my go-to spectrum analyzer for quickly checking audio sources, etc.
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Regardless of the tool used, you need to lower the floor to -120 or -130 dB and make a spectrogram that is big enough to discern detail. Have at least 20 pixels per second. If Spek can only make small images, use SoX instead. Analyze at the difference channel for stereo files, which will reveal more artifacts.

I use the following command line for SoX for analysis. The remix effect adds one more channel with the difference between L and R.

sox.exe "INPUT.WAV" -n remix 1 2 1v0.5,2v-0.5 spectrogram -x 5000 -y 257 -Z -10 -z 120 -o "INPUT.WAV-lrs.png"

Instants where the signal falls below the "shelf" will show as black. You want the spectrum between 16 and 20 kHz to be quite "dense", and show no blocking at all for lossless sources. Encode a few 320 kbit files of different music genres yourself and analyze them to learn what to expect.
How to run it? I am sorry I am a noob
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3rd Party Plugins - (fb2k) / Re: foo_youtube
Last post by marc2003 -
Remove my script/component. Problem solved.
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Uploads - (fb2k) / Sample file
Last post by Case -
A sample file.
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As I was looking into AMR codecs, I've stumbled over this page: http://www.voiceage.com/Patent-Portfolio.html
I don't know how authoritative it is, but I was told, that U-Boat patents are mostly a thing of the past. Given what is described there, patents for xHE-AAC will expire in 2031 - or to be more precise: the last one of those will expire in 2031.

According to this: https://www.iis.fraunhofer.de/en/ff/amm/impl.html there are SDKs available, that run on a plethora of systems, including PC (including Linux). How to get those SDKs, I have no idea.

VoiceAge "sells" xHE-AAC: http://www.voiceage.com/xHE-AAC.html however I'm not sure how they sell it. They claim to be a "codec provider", I wonder if that means, they do anything beyond licensing, really. As far as I understand it, the SDK or whatever software has to come from FhG IIS anyway.

I occasionally check out the usual places on the internet for a pirated copy of the SDK, but so far I couldn't find any. I guess since there aren't that many users, the probability of the SDK leaking outside of its designed realm is rather minimal. And tbh, I think this is the only way we'd get a chance at having a go at xHE-AAC for anytime soon.
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General Audio / Re: Powering Up Audio System
Last post by dc2bluelight -
Ever actually do this?  The results are usually very stunning for what they don't show.
Yeah, that was sort of my point.  Unless the amp is repeatedly asked to dump nearly clipping level power into a load you really don't see line current wobble.  What people don't realize is now far from that condition normal operation really is.
As long as power amps are designed to satisfy imaginary requirements created by audiophile myths such as all channels driven power ratings, there is a strong exposure to excessive inrush currents.
Ah yes, "all channels driven"... the mythical, statistically impossible condition.
One simple solution to this problem might be to use a more realistically sized power amp to drive the subwoofer.

BTW turnon thumps and inrush currents need not have any relationship to each other.  They are separate problems that can easily have separate causes.



Yes, that was the source of my "band-aid" comment.  I see people solving the transient problem with power sequencing when it's source is bad design.