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1
Imgur is fast enough for now, although it does have a time expiry for anonymous uploads if they're not accessed for several months. I'm not sure if the same applies to authenticated uploads, as I have some uploads that I don't think have been accessed for years, rather than just months.
3
This is for Commodore 64, I'm using a 90s cassette-to-line-in-adapter in the tape player, and it works really well.

And 622kB instead of 1705kB (A tape turbo) is of course no big deal. But it somehow hurts deep inside when I know 7z makes it 5kB. :D

I found this: http://www.foobar2000.org/components/view/foo_unpack_7z

... but alas, foobar mobile don't seem to have support for add-ons.
4
Audio Hardware / Re: Interview Time
Last post by Arnold B. Krueger -
"Any legacy SS amp that has a single power supply for its output stage generally has a large DC blocking capacitor that will interact with some woofers to create relatively large amounts of bass boost (YES, BOOST!)  - often several DB in the lowest normal octave."

What is a "legacy SS amp"? How far back are you going in time? 10 years? 20 years? More?


I'm talking second generation SS amps - late 60s, early 70s.

Notable because they use silicon output devices (not germanium types like the first generation), typically no coupling transformers, single-ended power supplies, output coupling caps.  Lots of Japanese receivers and amps, as well as the Dyna 80 and 120, the Heath AR 15, AR amplifier, etc. The AR amp was a bit of a throwback as it had a driver transformer. Mostly topped out at 50-60 wpc.  The next generation included the early Phase Linears, Crown DC 75 and 300, Dyna 400,  etc - notable because they had split power supplies, no output coupling caps, more power 150-200 wpc, but still had SOA problems.
5
Your best bet is to research a way to store the demodulated data into a player that will remodulate it back and output the signal. There are some mobile apps that do that but I don't remember their names etc. They store the actual data carried on the audio part but they are saved as data and not audio, which should be some KB of data and upon demand they will modulate the file and play it back from their headphone jack. If I'm not wrong asciiexpress.net online portal actually works that way.

I could help more if I knew exactly for what system you try to achieve this.
6
Most audio tape-based computer data formats (record and play on standard audio tape deck) are designed to work with limited frequency response and low SNR, speed variations, and phase shifts. They typically only need telephone grade bandwidth and SNR (4 KHz bandwidth, 40-55 dB SNR). You could use a lower sample rate such as 11 or 8 KHz / 8 bit.
Do consider the playback mechanism, though. It's no use using 8/8 format, or some specialised codec format, if the playback device doesn't support it.
Personally, I'd use MP3 encoding.  About 10 years ago I had to record the training sequence and data stream of a 2400 bps modem and send it to an overseas lab. I recorded it at 16/44.1 mono and converted to 128 Kbps MP3. The lab had no difficulty playing it into their analyser. I just now took one of the original files and compressed it with LAME at quality 9 (VBR, 45-85 Kbps) for a 20:1 reduction.  Overlaying the input and output waveforms shows an almost perfect match.
7
General - (fb2k) / Re: Replaygain settings per folder
Last post by lvqcl -
automatically turn on track-based replay gain
Remove album gain tags from these files.
8
General - (fb2k) / Replaygain settings per folder
Last post by hlloyge -
Hello all!

I have one question (and proposal) for possible situation.

I have more than few compilation folders where I put different music from different albums, and then playing them back. I would like to automatically turn on track-based replay gain and set boost gain when I load that folder into foobar. For this to be achieved, I have one possible solution - manually create a file in the folder, text, for example, rgain.set, and inside that file would be information for replaygain configuration of foobar2000 player:

Quote
sourcemode=track,album
processing=applygain,applygainpeak,preventclip
preamp=+6dB

(for example).

This file, when found in folder when adding files to playlist, would override current RG configuration and be applied to files in that folder by default. Manual change could be possible, this would just load 'default' configuration for that folder.
Is this possible to do, and is there interest for that? I am very interested :)
9
This may not be applicable to your situation, but the most straightforward way to accomplish this would be to port the utility that generates the wav file from the computer data, and then simply have Android generate and play the audio on-the-fly from the original data you want to transfer. Of course, this assumes you have the source code and programming skills.

Otherwise, WavPack lossy might be a good choice because it leaves the waveform unaltered. Regular lossy codes based on human hearing models are probably not recommended.
10
You can try other losless codecs, like Monkey's Audio or Wavpack. But, I've seen people had compressed C64 tapes in mp3 format and loading them from portable CD player through some kind of interface, replacing cassette player.