Archive for July, 2005

ClickTrack

Sunday, July 17th, 2005

ClickTrack is a little tool for easily adding click tracks to your Standard MIDI Files (.mid). Click tracks are almost indispensable if you play live with both a sequencer (machine) and a drummer (human) and the human is acting as a timeline-slave to the machine.

At work

The story
Keyboarder uses sequencer and is fed up with bad timing of Drummer at last gig. Drummer is always fed up with Keyboarder, but this time Keyboarder has gone too far as Drummer did not hear anything from him at all over the monitors. So Keyboarder adds click tracks to his sequences and Drummer borrows a set of headphones from Girlfriend and henceforth performs straight to the tic-toc-toc of the sequencer. Guitarist does not take part in this discussion. He was clearly audible on stage, shouldn’t this be enough anyway?

The truth
A good friend of mine asked me for help to make all his tens of MIDI files contain those click tracks. After trying to rework some files manually in Cubase we decided that it would be much nicer to have a tool like ClickTrack.

About Standard MIDI Files (SMF)
SMF are a common and standardized way to interchange time-stamped MIDI data between computers or MIDI devices. The file format has been specified by the MIDI Manufacturers Association (MMA). SMF are often used on stage for playback with hardware sequencers, and this is the only file format that can be processed with ClickTrack.

  • SMF Format 0
    Format 0 files comprise of one track that may contain MIDI data on all channels 1~16. Additionally, all meta events like tempo, time signature or lyrics are located in this one track. Format 0 is especially suitable for load-while-play devices due to linearity between time- and fileposition of events.
  • SMF Format 1
    Format 1 files comprise of up to 65536 tracks. Track 0 is kind of a mastertrack, usually hidden to the user and containing meta events like songname, tempo and time signature. Tracks 1~65535 are the ones you see in your sequencer application and that each may contain MIDI data on all channels 1~16. Format 1 is especially suitable as interchange format for complex arrangements with more than 16 part multitimbrality and for dedicated routing of tracks to MIDI outputs on hardware sequencers. Not many load-while-play devices support format 1 as timely subsequent events are staggered trackwise along the file.

It is important to realize the differences between format 0 and format 1 to select the most appropriate variant for your application. ClickTrack allows you to load, process and save files of both formats, and thus it may also be used as a conversion tool. Furthermore, it offers a few goodies to edit song- and tracknames, to intelligently transpose songs and tracks, to reorder or mute tracks and to remap MIDI channels.

Menu File
Files can be opened as usual but drag & drop is supported and recommended. There is no Save option but only Save As.. instead to avoid erroneous overwriting of your original files.

Menu File

Menu MIDI
There is an Offline option to close the MIDI output and make it available to other applications without closing ClickTrack. May be useful.

Menu MIDI

Song Info
The Song Info shows the name of the song and offers a global transposition combo box. The songname is not the filename but the meta event trackname of track 0 in a format 1 file or the one and only trackname in a format 0 file. Double click on the songname field to set or change this value. Global transposition means that all note events not on channel 10 and all tracks not mapped to channel 10 are transposed. MIDI channel 10 is usually used for drums.

Song Info

SMF Info & Save Options
The SMF Info displays the format of the SMF, the number of tracks and the division. If you load format 0 files, the number of tracks is set to 16 at first, as channels are mapped to tracks. Within the Save Options you may change the format to be saved and the division value. If you do not know about the division parameter you should let the combo box setting on Keep.

SMS Info & Save Options

Tiny Tracklist
The Tiny Tracklist provides a quick overview on the tracks. If you click the check box beneath a trackname the track will be muted while playing. Additionally, muted tracks, when saved to format 1, will still exist to keep up the track order but will contain no note events. Muted tracks, when saved to a format 0 file, will be deleted concerning their note events. Double click on a trackname to set or change the value but be aware that tracknames will only be saved with format 1.

Tiny Tracklist

The four combo boxes on the right allow you do some track specific modifications. The Channel option, when set to any after loading, indicates that the selected track contains MIDI events on more than one channel, otherwise it is set to the appropriate value. To force events on this track to be put out an a specific channel, just set it on the desired value. With the Transpose combo box you may transpose all note events on the selected track by value -24~+24. Just in case the track sounds too bassy low or too screamingly high after transposition, you may force a certain key window for all note events with the Wnd bot and Wnd top combo boxes. Any notes below or above the given key window will be wrapped one octave above or below the original value. This often leads to very interesting results, maybe try it on the bass track first.

Click
The Click options should be generally obvious. Imagine you have a 16 track format 1 file and want all your files to have a click track 20 in the future. Just set the Track combo box on value 20 and go for it. If you leave it on value 10 and your drum parts are on track 10 then the click track will be merged into the existing track.

Click

Select accent and default note with the Acc and Def combo boxes. Of course, for proper positioning of accent and default note, the MIDI file must contain time signature events. If it does not, you may work around by setting these notes on the same value. Adding a click track may not be undone currently, this is yet a one-shot feature so you should always add the click track finally after having played with the tracklist options.

Download
ClickTrack is built with Borland C++Builder 6 using Theme Manager by Mike Lischke. It is designed to run on Microsoft Windows 2000/XP and comes with Inno Setup installer. Please tell if you find errors or want further features to be added, your feedback is welcome.

ClickTrack is freeware and provided to you as is. It is assumed to work properly but may be erroneous and have malicious effects on your computer systems or MIDI devices. Download and use at your own risk.

Download ClickTrackDownload ClickTrack 1.0 (~613KB)


Old site stuff removed

Saturday, July 16th, 2005

Just logged on to our webserver and removed the files with a few clicks. Did you ever wish that parts of your history could be rubbed out that easily? Maybe I should post these words wrapped into embarrassment-tags ;-). But as in real life, this plan will not work out, of course. Searching for terms like “web archive” will bring up http://www.waybackmachine.org/ in example. If you forgot about the how and when of your first website, it will take you willingly back to the old times, no matter if you like it or not.


Site update

Thursday, July 14th, 2005

Saying goodbye to old site layout

After almost four years with the old frame-based design, I decided to start something new. Ok, the old site may have been just moderately ugly, but from the technical point of view it was really bad. Moved over the old contents so far, and most of the old links will be valid for the next few days until having informed my dear top-referers. Also you may use http://www.kessener.net/hajo/ to get to the old site. And yes, I will switch to something else than the default template asap ;-).


Accu-Trainer AT1 repair

Monday, July 11th, 2005

The Voltcraft Accu-Trainer AT1 is a charging device for AA and AAA NiMH and NiCd cells. It comes with an integrated switching power supply for direct mains connection instead of using a wall wart. The AT1 and it’s relatives AT2, AT3 and AT8 are popular chargers, at least in Germany, with the reputation of treating accus nicely and not frying them.

AT1 on desk

A few month ago I got this piece at our local Conrad Electronic store in Hannover. They have these plastic boxes located near the cashpoints where you can find faulty or B-stock pieces at reduced prices. This stuff is definitely worth a look as very often you will get properly working units with only a few cosmetic drawbacks. BTW: You know that you got an “out-of-the-plastic-box” unit if there is a big cross scribed somewhere on the housing with a screwdriver or knife. Keep an eye on it, maybe this is your next eBay snip.

Cross on bottom side

Well, this time it was not cosmetic but a real fault. So I disassembled the AT1 and put it on the desk with a breadboard as isolator and powered up the isolating transformer to go for error search. There was neither smoke nor smell nor any other sign of life, nothing obvious. The switching power supply did not look as if this job would be fun, anyway.

AT1 disassembled

Switched off and checked the semiconductors with ohmmeter and diode tester, checked resistors and capacitors without result. To check the capacitors in-circuit I used a new toy, the Elektor In-Circuit Kondensator-Tester and found one capacitor with ESR value 1Ω to be possibly critical, two others had ESR value 0Ω which is optimal.

ESR check

Powered it up again and started measuring voltages. This is always a bit fiddly with mains on the board, even behind an isolating transformer. Beneath the controller PIC16C72A there was a three legged something hidden under a shrink hose that looks like a voltage regulator. On supposed input there were 14 volts, on output there was nothing and the output is connected to Vcc of the controller, hmm. Cut the shrink hose to have a look at the labeling.

Three legged something

Found an LM340T5 which is better known as 7805 voltage regulator. This is an easy one; you may be out of toilet paper but you will never miss a 7805 in your spare parts inventory. After replacing I did a quick check using a dead AA accu sticked with tape between the contacts and… yup!

Yup

Pulled over a new shrink hose, reassembled the AT1 and that’s it. If you own a dead AT1 maybe this post could be helpful. Although integrated in a very small housing and with internal power supply the device gets hand-hot normally which is a good perspective for long life and reliability.

AT1 at work