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Ogg Vorbis - General / nokia 222 + ogg vorbis?
Last post by sanskrit44 -
all i could find so far while searching is some device specs that even claim the phone is capable of playing back ogg files? actually this is not correct, it can only handle mp3 files.

so is there any chance to get ogg vorbis encoded audio files running on the nokia 222?
Listening Tests / Re: 192kHz Samples -- But Not Really?
Last post by bennetng -

Since we have an ABX log, I will demonstrate how to interpret the log and examine the flac files.

[1] Copy all the text in the log and paste it in the verifier below:

[2] Verify the SHA1 values in the ABX log and see if they are the files I attached.

[1] and [2] are not security measures to avoid cheating. For example I mentioned that mzil found a pair of 2L files with time alignment problem, it is possible that 2L would fix the problem later and update their files. The checksums are used to identify if the files are changed or not.

[3] Refer to the post below to identify and avoid some common ABX pitfalls.,110058.0.html

The points above have nothing to do with the audio files are synthesized or not.
Vinyl / Re: >20kHz content found in vinyl?
Last post by Arnold B. Krueger -
I'm bumping this topic after a long break, as I forgot about the thread.

I think Greynol is mainly the person editing the vinyl myths wiki entry, so hopefully he reads this. In any case, I still find the following quoted section a bit confusing and contradictory (I highlighted what I found most confusing/contradictory), and I didn't see any references to these claims (which are fairly recent). A quick Google search didn't reveal anything that backed up the claims of "common 23-24 kHz audio content at significant amplitude on vinyl records" (but a more thorough search might reveal this). I still haven't found any concrete evidence that shows that vinyl records have actual musical content to 23-24 kHz, where it is shown that the peaks above 20 kHz are actually music present on the master it was cut from, rather than just noise or distortion.

(from source sans formal citation)
tests have been conducted which deonstrate that a record can be played up to 1000 times before there is any measurable increase in distortion as a result of record wear

I think that it is possible to do tests where low frequency tones on vinyl retain some semblance of their original integrity over multiple playings. 

One problem is that the original integrity of even low frequency signals on vinyl is not that good. About a decade ago when I had clients who wanted vinyl transcribed I assembled a vinyl playback system and bought some of the best test records could find as new products and also legacy test LPs that were NOS.  I don't recall ever seeing nonlinear distortion that was much below 0.2% under ideal conditions.  While that may be hard to hear, by modern digital standards it is piss-poor.  Things were worse as the frequencies rose.

Playing test records provided technical indications of other problems that are likely to be audible, including noise and FM distortion (Jitter or if you will Flutter and Wow). There will be audible low frequency FM distortion if the record is not nearly perfectly physically flat and centered. Neither are universal absent  and one or both are common.

There is additional FM distortion due to the friction of the needle in the groove varying its drag as the program material changes.

There is additional FM distortion that is due to the nearly universal  use of offset (angled) tone arms.  Note that near the end of the mainstream vinyl era a number of straight line tracking record players were sold by mainstream audo manufacurers, but as the LP became a niche product, these disappeared off of the market to a very large degree.

Many cartridges have magnetic circuits that fail to be sufficiently  uniform over the area where the coil or magnet travels and there will also be amplitude modulation as the magnet or coil moves about due to off center punching and records that are insufficiently flat.

I have also listened to presentations by collectors of legacy audio gear who experimented with CD4 records and decoders. The presenter described assembling a modern vinyl playback system with a modern cartridge and stylus that was designed to optimize ultrasonic response. They were successful in obtaining an indication of ultrasonic carrier detection on first playing. After something like 10 playings, the indication was lost. The presenters conclusion was that the ultrasonic content had been worn off in just a few playing's.  I believe that this carrier was in the range of 35 KHz. 

I understand that depending on stylus shape there is a phenomenon called "Pinch Effect" where the groove requires an impossibly narrow stylus to be tracked accurately  because modulation causes the groove to turn which reduces its cross section as seen by the stylus  in the plan view. For modern elliptical designs the frequencies where pinch effect becomes significant may be above 12-13 KHz. Pinch Effect reduces media life, causes nonlinear distortion, and reduces stylus  life.

As far as high frequency content goes, with a few notable exceptions almost all LPs were cut from either analog tape or digital masters.

The best of the digital masters of the day generally  had 48-50 KHz sample rates, so obviously content above 24-25 KHz would be impossible.

The overwhelmingly most common way in the day  to produce  recordings and cut a  lacquer involved 15 ips magnetic tape. Ultimately the high frequency band pass of these tapes was limited by the playback head gap. Making this gap smaller required precision but also increased the probability of introducing  amplitude variations above 10 KHz and also drop outs or loss of useful output for brief periods. Both of these effects are easy to see using test tones and an oscilloscope, and can be audible. Drop outs of any significant duration are so audible as to ruin the work. For these reasons professional tape machines had playback heads that restricted the high frequency band pass to about 24 KHz @ - 3 dB.

So a LP high frequency power bandwidth started being significantly limited in ways that were never practical to correct or compensate for  above 12 or 13 KHz, and completely died above 24 or 25 KHz for lack of program material coming from the master recording, whether digital or analog.
Validated News / Re: Opus 1.2 is out!
Last post by Emre -
opus 1.2.1 is here. 
3rd Party Plugins - (fb2k) / Re: foo_upnp
Last post by alb_qwerti -
Hi, I tried it but it is different in design.

It's only an output to another device, not a real server.
Anyway it didn't work too, there was an errore message. Today I'll try again and I let you know.
Maybe there are some ports to open in the router?

3rd Party Plugins - (fb2k) / Re: foo_upnp
Last post by MojoBass -
Did you try foo_upnp_out, see here? Works well for me.
WavPack / Re: How about multi-threaded wvunpack?
Last post by bryant -
So wvunpack is faster than FFmpeg for single threaded decoding, but with 8 threads FFmpeg is a lot faster (as expected).
Wow, I am really surprised by that level of improvement...thanks for testing and posting this!
Listening Tests / Re: 192kHz Samples -- But Not Really?
Last post by Chibisteven -
The ABX result.

foo_abx 2.0.2 report
foobar2000 v1.3.15
2017-06-26 19:17:40

File A: [44k] Flying Battery Zone Act 2.flac
SHA1: 04dbee201c45e5914510b6da64b933dac5acf152
File B: [192k] Flying Battery Zone Act 2.flac
SHA1: bb1b5abc8d76cf17afa6c485d071a5a051b2438c

DS : Primary Sound Driver
Crossfading: NO

19:17:40 : Test started.
19:18:19 : 01/01
19:18:58 : 01/02
19:19:09 : 01/03
19:19:20 : 02/04
19:19:29 : 03/05
19:19:41 : 03/06
19:19:51 : 03/07
19:20:02 : 04/08
19:20:10 : 05/09
19:20:19 : 05/10
19:20:26 : 06/11
19:20:34 : 06/12
19:20:41 : 06/13
19:20:48 : 06/14
19:20:55 : 06/15
19:21:03 : 07/16
19:21:03 : Test finished.

Total: 7/16
Probability that you were guessing: 77.3%

 -- signature --
Listening Tests / Re: 192kHz Samples -- But Not Really?
Last post by Chibisteven -
You still don't understand what I mean?
Read Reply#26 and get the file.

[1] The file "R-Type(HES).7z" is the source, inside of it is a 16-bit 96khz wav file.
[2] This *wav* file is resampled to 44.1k by SoX to another lossless format, like wavpack or flac.
[3] ABX file [1] and [2] by using the ABX plugin.

Totally unrelated to what you said isn't it? The ABX log will contain the checksum of file [1] and [2].

In case others would like to verify and reproduce the ABX test, file [1] and [2] will be used so that the checksum can be verified.

Understand now? It is a comparison of normal lossless audio file like flac and wavpack, tell me how can you make "R-Type(HES).7z" change the sound completely by using SoX?

To answer how to change the audio with SoX. with those particular files.  Use any sample rate below 32 KHz.  If you really want to muffle it use something like 8 KHz.
Listening Tests / Re: 192kHz Samples -- But Not Really?
Last post by Chibisteven -
Actually I used a MIDI from the FM set and not the General MIDI set.  Difference in panning, instrumentation, and use of effects such as reverb and changing drumkits.

FM Set - Optimized for OPL3 sound cards of the day.  Hard panning, use of certain instruments to work around limitations of OPL3 hardware.

GM Set - Made for General MIDI wavetable synthesizers of the day (probably optimized a bit for the Roland SC-55 add-ons of the day???).  Soft panning, effects such as reverb, drum kit changes between songs.