Re: [SlimDevices: SqueezeCenter] Replay Gain: how can Peak > 1? And how to create headroom for Gain>0
rbl wrote: > So basically another 6dB headroom would capture pretty much everything, > and I would have thought that is within the SB3's 24bit DAC and noise > floor of a decent system. > > Would be great if LMS had a pre-gain feature of some sort to help with > this. But I guess I can either use 'loudgain' > (https://github.com/Moonbase59/loudgain) as suggested by MainSqueeze, or > just subtract 6.00 from all the existing RGs which presumably amounts to > the same thing and my CPU will thank me! For standards compliance and compatibility I'd be inclined to keep to either -18 or -23LUFS. If you do decide to set your own target, tailored to one particular playback device and scenario, this 10-year-old thread on 'using MP3Tag to batch process RG values' (https://forums.slimdevices.com/showthread.php?82796-Replaygain-batch-editor) might be of interest. (And your CPU will love -that-.) MainSqueeze's Profile: http://forums.slimdevices.com/member.php?userid=62220 View this thread: http://forums.slimdevices.com/showthread.php?t=112866 ___ Squeezecenter mailing list Squeezecenter@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/squeezecenter
Re: [SlimDevices: SqueezeCenter] Replay Gain: how can Peak > 1? And how to create headroom for Gain>0
slartibartfast wrote: > If LMS cannot apply the required replaygain value because the peak of > the waveform is already full scale then turning off replaygain won't > make any difference. > True. Luckily, I don't have any classical music that's mastered like that. The Schoenberg "track" that I referred to in my earlier post, for example, has an RG peak -- if that's the word -- of 0.039185, which without RG is very unlikely to clip. (I quite like the idea of asking 'Iggy Pop to remaster' (https://archimago.blogspot.com/2017/08/musings-increasing-dynamic-range-of.html) Schoenberg and Webern, though. Anton, Anton, I can tell / Your pretty face is going to hell...) slartibartfast wrote: > Foobar 2000 also has a clipping prevention feature but it doesn't appear > to work. I have an album with Album gain +2.47 dB and an Album peak of > 1.000 whether calculated with clipping prevention enabled or not. I must > be missing something. I don't use Foobar myself, so I really don't know, I'm afraid. That might be a question for 'hydrogenaudio' (https://hydrogenaud.io/index.php?board=28.0), where I think much of the discussion around Foobar takes place. MainSqueeze's Profile: http://forums.slimdevices.com/member.php?userid=62220 View this thread: http://forums.slimdevices.com/showthread.php?t=112866 ___ Squeezecenter mailing list Squeezecenter@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/squeezecenter
Re: [SlimDevices: SqueezeCenter] Replay Gain: how can Peak > 1? And how to create headroom for Gain>0
LMS's clipping prevention considers two factors: the track peak and the amount of positive gain calcuated by ReplayGain. If those two add up to more than 0dBFS (or 1.0 on the ReplayGain scale), then LMS limits the gain to keep below that threshold. LMS's clipping prevention doesn't consider any additional headroom you might create, for instance by lowering the volume on your Touch or other player. Foobar calculates ReplayGain for a target level of -18LUFS (roughly equivalent to -89dB). That's fine for contemporary pop, rock, R&B, hip-hop and jazz, even reissues of (say) 1960s jazz, because most of those will have negative RG values. For classical music, which will often need positive gain to reach -18LUFS (as much as 27.53dB, e.g. for Schoenberg's "Kleine Klavierstücke", with similar values for Webern, Debussy and Stravinsky), you have two options: You can either use a more conservative RG setting. The excellent 'loudgain' (https://github.com/Moonbase59/loudgain), for example, allows you to set the target level at -23LUFS, which would allow an additional 5dB or so in positive gain. (-23LUFS is from the original EBU R128 specification, while Foobar's -18LUFS is a compromise for the sake of compatibility with the old RG standard and modern consumer electronics, incl. mobile phones). Or you can switch off RG whenever you play classical music (and anything else with serious dynamics, for that matter). That's the approach I ended up with, partly because I don't have any classical playlists (I almost always play whole works), partly because I hesitate to apply -23LUFS attenuation in the digital domain, when I'll often have to compensate for that by turning up the analogue volume (i.e. I doubt it makes sense to first lower SNR only to then amplify the result), and partly because my amp comes with a handy sensitivity switch that adds 6dB in gain. Oh, and by the way, you may find peaks greater than 1 in FLAC files as well, especially when you use a ReplayGain scanner that aims to detect intersample "true peak" values. MainSqueeze's Profile: http://forums.slimdevices.com/member.php?userid=62220 View this thread: http://forums.slimdevices.com/showthread.php?t=112866 ___ Squeezecenter mailing list Squeezecenter@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/squeezecenter
Re: [SlimDevices: SqueezeCenter] Using Sox to parametrically equalizing I'm losing seek functionality. Could it work?
Well, the short version is: I can extend gormans custom-convert to
apply equalizer settings to remote streams as well, but in doing so Im
losing the ability to seek within individual streams. The long version
follows:
My test case is a Bandcamp URL:
Code:
https://t4.bcbits.com/stream/bd49083b058f575632b3f068c7a448d0/mp3-128/2133326474?p=0&ts=1594389689&t=68fef2d2b76656e8683f1e730ff06bff6fd5deb0&token=1594389689_c819955ff7b75464b8a3f285298ec5ec9c95a07a
This is the URL that LMS opens when you play back that particular
Bandcamp tune (Fela Kutis Sorrow, tears and blood) via Michaels
Bands Campout plugin. (It seems that these URLs change over time, but
for testing purposes you can use any bc.bits.com URL that you find in
your server log while playing back a Bandcamp tune.)
Ive chosen Bandcamp because Ive been using it since 2010; unlike
others I've tried in the past, e.g. Spotify, Tidal, Deezer, it has the
sort of music I like and havent yet got in my collection. The URL opens
a 128-bit MP3 stream, so sending it through any sort of equalizer or
effect is a bit silly. But for a proof of concept it'll do.
First I wanted to check if playback, transcoding and seek worked outside
LMS, so I tried:
Code:
# Playback works
ffplay
"https://t4.bcbits.com/stream/bd49083b058f575632b3f068c7a448d0/mp3-128/2133326474?p=0&ts=1594389689&t=68fef2d2b76656e8683f1e730ff06bff6fd5deb0&token=1594389689_c819955ff7b75464b8a3f285298ec5ec9c95a07a";
# Transcoding and seek work
ffmpeg -ss 2:00 -to 3:00 -i
"https://t4.bcbits.com/stream/bd49083b058f575632b3f068c7a448d0/mp3-128/2133326474?p=0&ts=1594389689&t=68fef2d2b76656e8683f1e730ff06bff6fd5deb0&token=1594389689_c819955ff7b75464b8a3f285298ec5ec9c95a07a";
-f wav output.wav
# Transcoding, seek and piping the results to sox works
ffmpeg -loglevel quiet -ss 2:00 -to 3:00 -i
"https://t4.bcbits.com/stream/bd49083b058f575632b3f068c7a448d0/mp3-128/2133326474?p=0&ts=1594389689&t=68fef2d2b76656e8683f1e730ff06bff6fd5deb0&token=1594389689_c819955ff7b75464b8a3f285298ec5ec9c95a07a";
-f wav - | sox -t wav - -t flac test.flac gain -6 bass -20
# Transcoding, seek, piping through sox and playback on stdout work
ffmpeg -loglevel quiet -ss 2:00 -to 3:00 -i
"https://t4.bcbits.com/stream/bd49083b058f575632b3f068c7a448d0/mp3-128/2133326474?p=0&ts=1594389689&t=68fef2d2b76656e8683f1e730ff06bff6fd5deb0&token=1594389689_c819955ff7b75464b8a3f285298ec5ec9c95a07a";
-f wav - | sox -t wav - -t flac - gain -6 bass -20 | play -
But when I try to apply this to LMSs custom-convert, I come unstuck. No
matter what stream mode I choose (I or R) and whether I use $PATH$ or
$FILE$ substitution strings, the results are the same: LMS applies the
SoX effects to the stream but when I try to seek within the track,
playback pauses the log reports a jumpToTime then resumes from the
beginning of the track.
The custom-converts Ive tested:
Code:
# version 1
mp3 flc * 00:00:00:00:00:00
# F:{PATH=%f}R:{PATH=%F}T:{START=-ss %t}
[ffmpeg] -loglevel quiet $START$ -i $PATH$ -f wav - | [sox] -D -q -t
wav - -t flac -C 0 -b 24 - bass -20
# version 2, replacing separate F and R variables with FR and $PATH$ with
$FILE$
mp3 flc * 00:00:00:00:00:00
# FRT:{START=-ss %t}
[ffmpeg] -loglevel quiet $START$ -i $FILE$ -f wav - | [sox] -D -q -t
wav - -t flac -C 0 -b 24 - bass -20
# version 3, adding an END variable
mp3 flc * 00:00:00:00:00:00
# FRT:{START=-ss %t}U:{END=-to %v}
[ffmpeg] -loglevel quiet $START$ $END$ -i $FILE$ -f wav - | [sox] -D -q
-t wav - -t flac -C 0 -b 24 - bass -20
Searching the forums for "jumpToTime", Google finds only two pages of
results, none of which appear relevant.
I've attached a server log that shows two "jumpToTime" events.
What am I missing? (It wouldnt be the first time Im missing something
obvious.) Or is this simply something that cant (yet) be done?
+---+
|Filename: jumpToTime.txt |
|Download: http://forums.slimdevices.com/attachment.php?attachmentid=30958|
+---+
MainSqueeze's Profile: http://forums.slimdevices.com/member.php?userid=62220
View this thread: http://forums.slimdevices.com/showthread.php?t=112497
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Re: [SlimDevices: SqueezeCenter] Using Sox to parametrically equalizing I'm losing seek functionality. Could it work?
gorman wrote: > Hi! Did you survive the pub? Waiting for new debug lines :-) Easy, Buster. I've got a few other things on, too, you know. ;) Anyway, I've already discovered that not all remote streams are in fact remote. Plugins apparently are "streamMode: I" rather than "R", even though they present a URL as their $PATH$. I think. Anyway, I'm making progress, and hope to have something for you guys to test and laugh at within the next couple of days. MainSqueeze's Profile: http://forums.slimdevices.com/member.php?userid=62220 View this thread: http://forums.slimdevices.com/showthread.php?t=112497 ___ Squeezecenter mailing list Squeezecenter@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/squeezecenter
Re: [SlimDevices: SqueezeCenter] Using Sox to parametrically equalizing I'm losing seek functionality. Could it work?
gorman wrote: > > As for your question above, with the player.source debug log active, try > to play an mp3 stream of your choice and post the tokenized command > here. From there we can work it out, I hope. Great. Sounds like a plan. What I'd like to do is see how far we can take custom-convert (for equalization, room correction, or personal preference, to compensate for room boundaries when positioning speakers, or even just to add reverb to every file played back through LMS if that's what it takes to bring down Babylon), then document what we've learned and post that either here or in a separate thread. But before I can do that I now have to go down the pub, get drunk and catch Covid-19 because Boris Johnson tells me that's the only way to save the economy... MainSqueeze's Profile: http://forums.slimdevices.com/member.php?userid=62220 View this thread: http://forums.slimdevices.com/showthread.php?t=112497 ___ Squeezecenter mailing list Squeezecenter@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/squeezecenter
Re: [SlimDevices: SqueezeCenter] Using Sox to parametrically equalizing I'm losing seek functionality. Could it work?
gorman was so right when he said, in post 20 above: gorman wrote: > > Convert.conf still is some sort of black magic stuff under many > aspects... it's good to have clarifications on the forums, when > possible. For future reference. Black magic indeed. Each little bit you learn only gives you a better idea of how much you don't yet know. Suppose, for future reference, one wanted to use convert-conf to transcode (and equalize) not only local files but also remote MP3 streams. That would require capability R, but how would one integrate that, for instance, with the two lines that work for transcoding local MP3s? MainSqueeze's Profile: http://forums.slimdevices.com/member.php?userid=62220 View this thread: http://forums.slimdevices.com/showthread.php?t=112497 ___ Squeezecenter mailing list Squeezecenter@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/squeezecenter
Re: [SlimDevices: SqueezeCenter] Using Sox to parametrically equalizing I'm losing seek functionality. Could it work?
One more question, if I may, to add to my little custom-convert documentation project: the default convert.conf file lists only three "current" device types: slimp3, squeezebox and * (for all types). Do you know how one might specify more recent models, e.g. Boom and Touch? What are their device type codes? MainSqueeze's Profile: http://forums.slimdevices.com/member.php?userid=62220 View this thread: http://forums.slimdevices.com/showthread.php?t=112497 ___ Squeezecenter mailing list Squeezecenter@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/squeezecenter
Re: [SlimDevices: SqueezeCenter] Using Sox to parametrically equalizing I'm losing seek functionality. Could it work?
I swear I searched that manual on Sourceforge several times for "-C". It turns out the manual uses en dashes rather than just ordinary hyphens... Still, now that I've recovered from the embarrassment: if "-C" specifies the compression rate, in this case for output to FLAC, then it should be safe, on a modern machine, to omit that option from the custom-convert command and go with SoX's default rate of 5, shouldn't it? MainSqueeze's Profile: http://forums.slimdevices.com/member.php?userid=62220 View this thread: http://forums.slimdevices.com/showthread.php?t=112497 ___ Squeezecenter mailing list Squeezecenter@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/squeezecenter
Re: [SlimDevices: SqueezeCenter] Using Sox to parametrically equalizing I'm losing seek functionality. Could it work?
I've now updated my custom-convert file, checked the server logs once more, and it's all good. No more "rejecting" this line or that, just "found command" and "matched", and the tokenized command on seeking within a track now reads: Code: Tokenized command: "/usr/share/squeezeboxserver/Bin/x86_64-linux/flac" -dcs --skip=0:28.86 -- "/home/michael/Music/Library/Rock & pop/Richman, Jonathan/1985 - Rockin' and romance/03 - Richman, Jonathan - Down in Bermuda.flac" | "/usr/share/squeezeboxserver/Bin/x86_64-linux/sox" -D -q -t wav - -t flac -C 0 -b 24 - equalizer 40.8 5q -11.4 equalizer 62.8 2.487q -11.3 equalizer 87.7 5q -3.2 equalizer 263 5q -7.4 & | Once again, thank you both. Like I said, I feel privileged to have had the support of two such knowledgeable forum members. Incidentally, you'll see that I've left in the "-C 0" option for now because, having gone through the documentation once more, I couldn't find any mention of it in the SoX or the FLAC manuals; does either of you know what "-C 0" actually does? MainSqueeze's Profile: http://forums.slimdevices.com/member.php?userid=62220 View this thread: http://forums.slimdevices.com/showthread.php?t=112497 ___ Squeezecenter mailing list Squeezecenter@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/squeezecenter
Re: [SlimDevices: SqueezeCenter] Using Sox to parametrically equalizing I'm losing seek functionality. Could it work?
bpa wrote: > > Now you need to wonder - did you ever notice the lack of equalisation > :-) Ha. I had a feeling you might say that. ;) The equalization only takes care of four bass peaks that acoustic treatment (which, besides several Squeezeboxes, was my best "HiFi component" ever) couldn't quite eliminate, and as long as I didn't search within tracks it worked, didn't it? MainSqueeze's Profile: http://forums.slimdevices.com/member.php?userid=62220 View this thread: http://forums.slimdevices.com/showthread.php?t=112497 ___ Squeezecenter mailing list Squeezecenter@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/squeezecenter
Re: [SlimDevices: SqueezeCenter] Using Sox to parametrically equalizing I'm losing seek functionality. Could it work?
Thank you! So just to make sure I've understood: The missing "capability T" is precisely the ability to "seek to a start time offset" that's defined in convert.conf, I suppose. The one I thought I could do without. ;) When LMS comes across a command that lacks a required capability (e.g. my sox string), it then executes the closest match it can find, e.g. the command you highlighted in red: Code: [flac] -dcs $START$ $END$ -- $FILE$ | [sox] -q -t wav - -t flac -C 0 $RESAMPLE$ - which is basically LMS's default FLAC-to-FLAC transcode command as per convert.conf. So if I want SoX equalization to work reliably, even when I'm advancing or rewinding a track, I need to use the custom-convert that gorman documented a couple of pages above. Is that correct? And thanks again for taking the time to look into this. I feel very privileged. MainSqueeze's Profile: http://forums.slimdevices.com/member.php?userid=62220 View this thread: http://forums.slimdevices.com/showthread.php?t=112497 ___ Squeezecenter mailing list Squeezecenter@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/squeezecenter
Re: [SlimDevices: SqueezeCenter] Using Sox to parametrically equalizing I'm losing seek functionality. Could it work?
I've attached the log; I hope you can make more sense of it than I can. Worryingly, there are several instances of this: Code: [20-07-03 17:15:44.3276] Slim::Player::TranscodingHelper::checkBin (252) Found command: [sox] -q -t flac $FILE$ -b 24 -t flac - equalizer 40.8 5q -11.4 equalizer 62.8 2.487q -11.3 equalizer 87.7 5q -3.2 equalizer 263 5q -7.4 [20-07-03 17:15:44.3279] Slim::Player::TranscodingHelper::getConvertCommand2 (382) Rejecting [sox] -q -t flac $FILE$ -b 24 -t flac - equalizer 40.8 5q -11.4 equalizer 62.8 2.487q -11.3 equalizer 87.7 5q -3.2 equalizer 263 5q -7.4 because required capability T not supported: Does that mean that LMS is ignoring the whole [sox] string? Or rejecting the custom-convert altogether? And what's "capability T"? Please let me know what you make of the log; I'd really appreciate it. Thanks. +---+ |Filename: Server log 20200703.txt | |Download: http://forums.slimdevices.com/attachment.php?attachmentid=30910| +---+ MainSqueeze's Profile: http://forums.slimdevices.com/member.php?userid=62220 View this thread: http://forums.slimdevices.com/showthread.php?t=112497 ___ Squeezecenter mailing list Squeezecenter@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/squeezecenter
Re: [SlimDevices: SqueezeCenter] Using Sox to parametrically equalizing I'm losing seek functionality. Could it work?
bpa wrote: > > Can you do a player.source log set to DEBUG when you use WebUI to jump > to a mid way point in a track. Will do but it'll be a couple hours or so before I'll get round to it, I'm afraid. Which log set should I choose from the dropdown at the top of the logging page? Or is choosing "Debug" for the player.source by itself enough? MainSqueeze's Profile: http://forums.slimdevices.com/member.php?userid=62220 View this thread: http://forums.slimdevices.com/showthread.php?t=112497 ___ Squeezecenter mailing list Squeezecenter@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/squeezecenter
Re: [SlimDevices: SqueezeCenter] Using Sox to parametrically equalizing I'm losing seek functionality. Could it work?
Just to confirm, I can both skip tracks (i.e. go to the next/previous track) and navigate to specific points in individual tracks (what in analogue days, we might have called RWD and FWD). I'm controlling playback via the web UI (mostly), iPeng (sometimes) and the touch interface of a Squeezebox Touch. All of them support navigating to individual points in a track. The one thing I can't do -- I've just tested all the use cases again, to be quite sure -- is use a Squeezebox Touch remote to RWD or FWD. When I press the respective buttons on the remote, playback does indeed skip to the previous or next track. But all other interfaces allow me to point the cursor or my finger wherever in the track I want playback to resume. MainSqueeze's Profile: http://forums.slimdevices.com/member.php?userid=62220 View this thread: http://forums.slimdevices.com/showthread.php?t=112497 ___ Squeezecenter mailing list Squeezecenter@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/squeezecenter
Re: [SlimDevices: SqueezeCenter] Using Sox to parametrically equalizing I'm losing seek functionality. Could it work?
gorman wrote: > > Can you skip with that line? Yes, I can skip (i.e. go to the next/previous track) as well as go to particular points in individual tracks using a Squeezebox Touch, the web UI (with Material Skin) or iPeng. Then again, I'm running LMS on Debian and using the Squeezelite version in the repositories, while you're on Windows, so perhaps that explains the different outcomes? If your approach (decode flac and mp3 to wav, pipe wav to sox, apply effects, then re-encode and output flac) works for you, I'd leave well alone (except that, for simplicity's sake, you may want to delete "-C 0" from the output specifications, as SoX's default FLAC compression of 5 will do just as well). Anyway thank you so much for documenting this; I've learned something new. MainSqueeze's Profile: http://forums.slimdevices.com/member.php?userid=62220 View this thread: http://forums.slimdevices.com/showthread.php?t=112497 ___ Squeezecenter mailing list Squeezecenter@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/squeezecenter
Re: [SlimDevices: SqueezeCenter] Using Sox to parametrically equalizing I'm losing seek functionality. Could it work?
gorman wrote:
> Ok, found solution for MP3s as well. Since I have music only in flac and
> mp3 my solution is complete.
>
> >
Code:
> >
> mp3 flc * bc:5f:f4:bf:3e:70
> # FT:{START=-ss %t}
> [ffmpeg] -loglevel quiet $START$ -i $FILE$ -f wav - | [sox] -D -q -t
wav - -t flac -C 0 -b 24 - gain -6.9 equalizer 30 0.43q +6.2 equalizer 699
2.00q +1.0 equalizer 2924 4.11q -1.7 equalizer 6031 5.05q -6.2 equalizer 9825
4.08q +2.2 equalizer 83 4.24q +1.3 equalizer 209 1.54q -1.2 equalizer 2842 0.1q
+0.2 equalizer 12443 1.29q +2.7 equalizer 19698 0.46q -11.8
>
> >
>
> I had to use ffmpeg because, as far as I can see, LAME does not accept
> time offsets when decoding
> (https://svn.code.sf.net/p/lame/svn/trunk/lame/USAGE). Don't know how
> the internal functionality of mp3 transcoding works (when lowering
> bitrates) because that is capable of seeking but the convert.conf line
> does not show any instruction for that. I could probably be using
> ffmpeg for flac files too but I guess there's no point or added
> value.
>
> If there are mistakes in my solution above, please do point them out.
>
> Edit: can anybody explain the use of the --until=v% command when using
> flac decoding? With the above line in ffmpeg I've got complete seek
> functionality and I don't get if I'm missing something and what would
> that be.
>
> Edit 2: since bpa asked for it, this is now the finalized portion in
> custom-convert.conf
>
> >
Code:
> >
> #Headphones
> flc flc * bc:5f:f4:bf:3e:70
> # FT:{START=--skip=%t}U:{END=--until=%v}
> [flac] -dcs $START$ $END$ -- $FILE$ | [sox] -D -q -t wav - -t flac -C 0
-b 24 - gain -6.9 equalizer 30 0.43q +6.2 equalizer 699 2.00q +1.0 equalizer
2924 4.11q -1.7 equalizer 6031 5.05q -6.2 equalizer 9825 4.08q +2.2 equalizer
83 4.24q +1.3 equalizer 209 1.54q -1.2 equalizer 2842 0.1q +0.2 equalizer 12443
1.29q +2.7 equalizer 19698 0.46q -11.8
>
> mp3 flc * bc:5f:f4:bf:3e:70
> # FT:{START=-ss %t}
> [ffmpeg] -loglevel quiet $START$ -i $FILE$ -f wav - | [sox] -D -q -t
wav - -t flac -C 0 -b 24 - gain -6.9 equalizer 30 0.43q +6.2 equalizer 699
2.00q +1.0 equalizer 2924 4.11q -1.7 equalizer 6031 5.05q -6.2 equalizer 9825
4.08q +2.2 equalizer 83 4.24q +1.3 equalizer 209 1.54q -1.2 equalizer 2842 0.1q
+0.2 equalizer 12443 1.29q +2.7 equalizer 19698 0.46q -11.8
>
> >
>
> If somebody is privy to the inner workings of sox, I wonder about two
> things:
>
> 1) The need to use the -D argument for no dithering.
> 2) The need to use the -b 24 argument for 24-bit output. This makes
> sense to me as it provides headroom for all equalization calculations.
> But I might be mistaken.
As to your two questions, here's what I concluded when I looked into
this a couple of years ago:
1. I don't think the -D option is needed when you've specified 24-bit
output. Here's what the SoX manual says:
"[B]y default, SoX automatically adds TPDF dither when the output
bit-depth is less than 24 and any of the following are true:
bit-depth reduction has been specified explicitly using a command-line
option
the output file format supports only bit-depths lower than that of the
input file format
an effect has increased effective bit-depth within the internal
processing chain"
2. SoX uses 32-bit processing internally for its effects, incl.
equalization, so that already offers plenty of headroom. But if you
didn't specify "-b 24", then SoX would apply dither to the output file,
esp. if the input file, like a lot of CD-quality music, is 16 bit. That
said, I gather that savage wars have been fought over dithering,
noise-shaping, etc., so I wouldn't want to comment any further.
With that out the way, I have to admit that I've never seen the point of
the commented line (# FT:{START=...) and the first part of the following
line, up to the pipe that sends output to SoX. Instead, I've been using
this stripped-back custom-convert for equalization for almost two years
now:
Code:
flc flc * 00:00:00:00:00:00
[sox] -q -t flac $FILE$ -b 24 -t flac - equalizer 40.8 5q -11.4 equalizer
62.8 2.487q -11.3 equalizer 87.7 5q -3.2 equalizer 263 5q -7.4
This works just fine, without the additional code. So what have I been
missing?
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Re: [SlimDevices: SqueezeCenter] Manually installing plugin zips
Well, here we are, still installing plugins a good two years after preparing for Armageddon. :) Because who'd want to sit through the apocalypse without Wagner in high-res FLAC piped to [sox] -G bass +11... MainSqueeze's Profile: http://forums.slimdevices.com/member.php?userid=62220 View this thread: http://forums.slimdevices.com/showthread.php?t=108414 ___ Squeezecenter mailing list Squeezecenter@lists.slimdevices.com http://lists.slimdevices.com/mailman/listinfo/squeezecenter
