Tag Archives: sound

siggen: Much to see, much to hear

Another brief tool this morning, and not so much because I don’t know how to use it, but more because I’m not sure what I’d use it for. This is siggen:


siggen is, as you might have already deduced, a signal generator, and in layman’s terms that means a sound creator. siggen lets you pick the quality, audio shape, gain, mono or stereo and so forth, and will produce a sound of those dimensions.

Using siggen is very easy; the tab key will cycle you through the fields, arrows increment the values or you can edit them directly. This means you can call on very specific shapes and sound forms, provided of course that your speakers can generate them.

siggen has some command-line flags, but they appear to be mostly settings that are available to you through the interface. So you can use them to set “default” values, if you like.

A few caveats: First, siggen is slightly old, and so it still seeks out /dev/dsp as your sound device. The easiest way I found to corral siggen was through the alsa-oss tool, and simply start both as aoss siggen. Perfectly usable and hearable.

Next, be aware that the settings are applied as soon as you change them. There’s no “apply” button or any sort of delay. So be careful with the gain value, if you’re tinkering with siggen at 6 a.m. on a Sunday. ๐Ÿ˜ฏ

And like I mentioned, the real bottleneck in using siggen — or any other sound generation tool — is the quality of your speakers. It’s easy to see where hardware is the real limiting factor here, since crappy speakers probably won’t do much to make siggen enjoyable.

Having said all that, and knowing what little I know about signal generation, I’m still searching for a reason to need this tool, aside from oscilloscope calibration. ๐Ÿ™„ It’s none of my business I suppose, since everyone uses a tool in their own way.

One last thing: I usually give points to programs for using color, but this time I’m on the fence. siggen’s color scheme is a bit of an encumbrance to me, but I’ll let it stand as proof that I don’t just hand out gold stars to any colorful interface. ๐Ÿ˜

P.S.: In Debian, but apparently not in Arch/AUR.

gom: Ten years gone

I joined the Linux crusade well after the advent of ALSA audio, so the old, old days of OSS are mostly lost on me. I think I experimented with OSS with a couple of very old laptops about three or four years ago, but never saw any real advantage to using the old audio subsystem over the new.

That’s vaguely ironic, since now I don’t see any advantage to using JACK or pulse audio over ALSA. ๐Ÿ˜•

The source files for gom show updates as recent as 2009 though, so it may be that you can still milk the OSS framework and have a viable audio mixer at the terminal.


That’s probably not a fair screenshot of gom, since I’ve really only installed the OSS framework in Arch, then force-built gom and gotten into the interface. It’s not really working the audio on this system.

But it should give you a general idea of what gom does, and how it handles itself. No color, nothing flashy, none of the wild craziness of alsamixer (that was a joke ๐Ÿ™„ ). Just channels and data, and the ability to control the audio at hand.

gom is in both AUR and Debian, but I only built the Arch rendition. Like I mentioned, I needed to build oss out of AUR, which was not a huge challenge. I had alsa-oss installed as well, but I don’t think that was necessary.

Using gom reminded me of both rexima and aumix, in that they all seem to take a back seat to alsamixer. It may be that gom had a finer hour ten years ago, but I’d be surprised if there were still OSS fans out there, and if they would put gom to use. ๐Ÿ˜ฆ

soundcloud2000: A quick listen

I like the way the soundcloud2000 home page describes the utility: “SoundCloud without the stupid css files.” :mrgreen:

I’m in favor of any tool that strips way the worthless lard that clings to most Web services, and I’ve been stuck in that mindset for the better part of the past decade. The sooner the general public realizes that lightbox effects and Web2.0 tripe are lipstick on pigs, we’ll all be much better off.

That’s not particularly aimed at SoundCloud; to be honest, I have very, very few dealings with SoundCloud as a whole, just by virtue of my relative disinterest. Listening to random recordings by random people in random places around this random world strikes me as rather … random. ๐Ÿ™„

All the same, if I was stapled to a chair and forced to pick through it, I would much rather have the benefit of soundcloud2000 than be required to navigate through its web interface.

2014-09-03-6m47421-soundcloud2000-01 2014-09-03-6m47421-soundcloud2000-02

Simple enough: Up, down, paging keys and return to listen. Left and right to seek, space to pause. The “u” key allows you user access.

And that’s about it. When they invent photos that can come embedded with sound (note to self: It can be done) maybe I’ll have more to exhibit. As it is now, I give soundcloud2000 a great big thumbs-up for good use of color, intuitive navigation and a snazzy opening screen. Have a star: โญ

And best of all, no stupid css files. ๐Ÿ˜€

timidity++: Miracle of miracles, again

Seems like I’ve been fighting to play back midi tunes of any sort, for years now. My most recent attempt with pmidi failed abysmally, and to be honest I had resigned myself to a state of midi-challenged.

All that changed this afternoon.

2014-05-27-jk7h5f1-timidity-01 2014-05-27-jk7h5f1-timidity-02

I’m having incredible luck with intractable software this year. First mutt, then slrn, and now timidity++. I better buy a lottery ticket. ๐Ÿ˜ฏ :mrgreen:

Even better, timidity++ greeted me with a snazzy ncurses interface that has almost everything I look for in an application, except color … unless you count the graphical spectrogram. But I’m willing to overlook monochromatics, since timidity++ actually plays back music — as in, the vibrations that go in my ears and tickle my brain.

Surprise, surprise. The only embarrassing part was that my speakers were turned to the max setting in every direction, which drew some attention from people around me. ๐Ÿ˜ณ

All that can be brushed aside, since this is my first successful attempt to get anything audio out of a midi arrangement. And it sounds quite good.

Just as a note to future self, I installed timidity++ and the timidity-freepats packages out of the Arch repos, copied /etc/timidity-freepats.cfg to /etc/timidity.cfg, and started up the timidity service with sudo systemctl start timidity. In other words, I followed the instructions in the Arch wiki. ๐Ÿ™„

Why this works now and hasn’t with other software in the past is a mystery for later. I’m pleased for once to have gotten music out of a midi program. I haven’t been this proud of an audio accomplishment since I milked Revolution Void from the ISA-based hardware in a 120Mhz machine. Those were the days. … ๐Ÿ˜€

steghide: Naughty, naughty

Things like steghide make me wonder exactly how much trouble I could stir up, given adequate time of course.

steghide is that tool you’ve known existed for a long time, but didn’t want to ask about. Put simply, steghide embeds encrypted files within others — possibly images or sound files.

I haven’t tried every variation, mostly because seeing steghide work once was enough to convince me that I can metaphorically stash it in my pocket, and save it for a time when I really need it.

Here’s what it looks like. Ladies and gentlemen, I give you … Tux.


You may recognize Tux from films and movies. And now, Tux’s doppleganger, his evil Captain Kirk:


You wouldn’t know it to look at him, but the Evil Tux is hiding a dark secret. We should suspect that just by looking at the file size.

kmandla@6m47421: ~/downloads$ ls -sh
 40K 2014-05-10-6m47421-steghide-tux-original.jpg
 48K 2014-05-10-6m47421-steghide-tux-embedded.jpg

There’s something … odd about Evil Tux. Check with steghide, and it will confirm it for us.

kmandla@6m47421: ~/downloads$ steghide info 2014-05-10-6m47421-steghide-tux-embedded.jpg 
  format: jpeg
  capacity: 1.9 KB
Try to get information about embedded data ? (y/n)

Naughty, naughty. What’s this you’re carrying, Evil Tux? And more importantly, where have you hidden it? ๐Ÿ˜ฏ

Try to get information about embedded data ? (y/n) y
Enter passphrase: 
  embedded file "secret.txt":
    size: 70.0 Byte
    encrypted: rijndael-128, cbc
    compressed: yes

steghide can yank that out of there in a jiffy. Just:

kmandla@6m47421: ~/downloads$ steghide extract -sf 2014-05-10-6m47421-steghide-tux-embedded.jpg 
Enter passphrase: 
wrote extracted data to "secret.txt".

kmandla@6m47421: ~/downloads$ cat secret.txt
Now is the time for all good men to come to the aid of their country.

Well that was anticlimactic. ๐Ÿ˜ You can try it for yourself if you like. The password is 12345.

steghide has a lot options, and what you see above was just blatantly stolen from the quickstart guide. I imagine just about any file could be embedded into any other; like I said though, I didn’t try every variation.

Don’t get yourself into trouble, now. ๐Ÿ˜ˆ

pmidi: If a tree falls in the woods

Apparently today is the day for sound players. This one, unfortunately, I don’t have much to show for.


midi is my No. 2 weak point after networking. That’s pmidi above, and as far as I can tell, it seems to be working.

Of course, I hear no sound coming out, which says to me that — for the umpteenth time — I have failed to correctly configure something.

I even tried to fiddle with my sound settings, but nothing interesting seemed to happen.

I only feel a little bad about that though, because there’s nothing much to show with pmidi. It can show a list of available ports, you can specify a port and specify a delay and … that’s all.

But other than that, there’s nothing graphical to show. No progress bar, no obvious controls, no interface aside from the files you list in the command.

So if there’s nothing to show, and if there’s nothing to hear, I have only one question: If pmidi falls in the woods and no one is there, is it working? ๐Ÿ˜•

abcm2ps and abcmidi: Coolness I didn’t know existed

I have all the musical talent of a brick. No, seriously. A dusty brick is more musical than me.

And a person’s got to know their limitations, so I tend to steer clear of anything music-related, if it doesn’t have a “play” button on it.

But the fun part of investigating all these little programs is finding gems like abcm2ps.


I know nothing — nada, zilch, zero — about musical notation or, for that matter, midi playback or conversion.

But with just a little bit of nudging and a quick search at abcnotation.com, and I get something that’s pretty cool — converting a short text file to something very visual.

But again, for all I know, that sheet music might actually just play random tones. I can’t read it. But the conversion looks pretty cool. :mrgreen:

Now, my next attempt was to run the same stuff through abcmidi.

Not so much luck there. What I got, or what I tried to play, ended up being empty, which is usually a sign that I did something wrong.

I suppose, technically, in an ideal world, there should have been sound coming out of my computer from somewhere. But it wasn’t happening.

I don’t blame abcmidi though. If I had more knowledge about midi, or maybe abc notation, or maybe just about music, my results might have been more … cool. ๐Ÿ˜‰

alsamixer: The interface we all know and love

I’ve had some adventures with the alsa libraries lately that warrant mentioning them here.

More specificially, alsamixer, the console interface for alsa, et. al.


You’ve probably seen alsamixer before, either in screenshots or in your own console adventures.

It works more or less as you might expect any other audio control panel to work — q.v., rexima and aumix.

Left and right sliders for each control, preset jumps at the number keys, mute buttons with M, and so forth. There are also some startup flags that will change the interface, or for example, remove the color.

The reason this becomes interesting, particularly to me, is because of the machine I’m typing on, right now.

Before I came across this Acer V5-122P, every computer I’d ever worked with had a simple enough audio card that alsa and company set themselves up without any intervention on my part.

And I will admit that in Linux Mint, which I showed a long time ago, there was also no problem with sound.

Under Arch however, there were some unusual behaviors.

To start, there were two labeled sound cards — HD-Audio Generic 0 and HD-Audio Generic 1.


By default, at boot, Arch latched on to the first available card, and used it as the default for the sound subsystem.

Where’s the harm in that? Well, as you can seen in the screenshot above, there is no audio control attached to card 0.

That, of course, confused the heck out of most audio players. mocp just refused to run. Others would run, but could generate no sound.

Card 1 was still accessible, by me, and I could control it, but there wasn’t a whole lot to be done in other software.

Before this gets too boring, I’ll cut to the solution.

In short, I had to feed the settings to alsa through the .asoundrc file in my home directory. Here are the settings that worked for me.

defaults.pcm.card 1
defaults.pcm.device 0
defaults.ctl.card 1

I will be honest and say I’m not really sure why each one works there. Linux Mint and other suite distros did this for me automagically.

I just twiddled with the settings until the right card appeared in music players — and in alsamixer when it started up. And so we’re back to alsamixer.

Since then it’s been nothing but happy puppies and sunshine. Isn’t the world a wonderful, musical place? ๐Ÿ˜€