Posts Tagged ‘Synthesis’

Getting gritty with the Casio CZ-101

October 29, 2007

The CZ-101 is the battery powered littlest sibling of the Casio line of cheezily named “Cosmo Synthesizers”. Utilizing phase distortion synthesis, both pleasing and abrasive sounds can be produced.

This sample pack concerns the grittier side of this cheap and appreciated 80’s technology

Music and More ADX-1 analog drum module

August 27, 2007

MAM ADX-1 – a german made analog drum brain, introduced in the end of the 90’s. A very cheap alternative to more high-end drum machines, but can it be so cheap and sound good at the same time? Let’s have a look.

The ADX1 is a rack-mountable module, very small and handy. The machine is kind of noisy, no doubt because of cost-saving. It is equipped with 50 (rather flimsy feeling) knobs distributed over 5 channels, logically laid out. The 5 analog synth modules are: bass, synth, snare, hihat and metal.

ADX-1

If you expect sounds like something from another cheap and portable drum machine, the Roland TR-606, chances are that you will be disappointed. Actually, this module has more in common in sound with the Tama/simmons drum brains of the 80’s. For the price though, you get acceptable possibilities to craft percussive analog sounds. Some sonic areas you won’t be able to touch, with a flawed implementation of the bass drum channel being the main issue.

The oscillators of the ADX1 seem to not reset at each trig – one hit bass drum trig might strike lucky and start at the exactly same time as the waveform cycle of the oscillator is begun anew, but with the next it is caught right in the middle of such a cycle. In the case of percussive synthesis, this tends to diminish the percieved impact of the sound. This will not happen with for example the T-bridge construction of the TR-808 bassdrum, or the TR-909, in which the oscillator is reset.

You can still pack some nice kraftwerkish drums, as well as Simmons-like boiiieuuws and general quaint electro percussion, but still, you are limited in scope due to the fact that the pitch of the bass drum oscillator is controlled by the same envelope that also controls the VCA.

The same economical design can be found in the snare section, where the envelope also caters to several duties, both the “snap” and the noise decay. The rest of the sound is made up primarily by two band-pass filters. When the resonance is cranked up on one of them, it serves to simulate a hit on the skin of a snare, creating the “body” of the sound. The second filter then can be used for modifying the noise part of the sound. A very economic solution, but it ends up sounding weak, with a very small sweet spot.

In the hihat and metal sections non-resetting oscillators are not such a problem, and the sweet spot area is a little bit larger. One can dial up some real nice sorts of hihats and metal sounding sound effects – obviously it also has its virtues.

When production of the ADX1 ceased when MAM bought up and incorporated into Terratec, the blow out price was below 150 EUR, which makes it easy to find them at around the same price today.

A related machine in the same class that might be a good investment is the virtual analog Korg ER-1 drum machine. Similarly, it is very drum brain-like implementation but also features a useful TR-X0X-style sequencer. It is also quite a bargain, and if you are not an analog taliban it might do well when some percussive bleeps & tweets are needed.

Nintendo Game Boy Synthetic Drums

August 27, 2007

Synthetic snares, bass drums, effects and percussive sounds created with LSDJ running on a first generation Nintendo Gameboy.

LSDJ is a tracker programmed for Nintendos classic hand-held gaming console by demoscener Johan Kotlinski. Kotlinski, also known as Role Model, wanted to create an easy-to-use – but still powerful – music software that could harness the possibilites that the 8 bit 4.19 MHz microprocessor could offer. In the year 2000, the first versions of LSDJ were released, but some development (mainly bugfixes) is still going on in 2007.

CPU and synthesis capability

 

The Game Boy does not contain a separate dedicated sound chip, but instead utilizes the architeLSDJ logocture of the Z80-like CPU to output 4 channels of sound. 2 channels are dedicated to square waves, with the two remaining channels tends to pseudo-random noise and wave-channel, respectively. LSDJ utilizes some clever ways of managing these channels, letting the user create sounds using crude forms of subtractive synthesis, wavetable synthesis and sample-based phoneme speech synthesis.

The square wave channels both feature volume envelope (attack/release) as well as Pulse-width modulation, but frequency modulation is only possible on the first channel, in the form of pitch bends, sweeps and vibrato controlled by a primitive LFO with several waveforms, going from slow vibrato to very fast mayhem (with wonderfully gritty results).

The user interface

All this is accessible on a screen with a video resolution of a mere 160×144 pixels with only the A, B, select and start buttons plus the directional pad to the left as controls. This clearly leaves a demand for an elegant and practical user interface. LSDJ presents us with exactly this, following in the steps of so-called “tracker” music sequencers like the legendary Soundtracker on the Amiga and Fasttracker and Screamtracker 3 on the PC.

Due to the open-ended structure of LSDJ, the user can dive into both simple and direct sounds as well as variations and complex combinations of the synthesis possibilities. The ability to program macro-events (a sort of sub-patterns that can be run in the background from the main pattern of a channel) makes it easy to produce the arpeggiated pseudo-chords recognized from for example SID tunes from the Commodore C64.

Kotlinski also made it possible for users to upload their own samples from their computer, through down-sampling and uploading to the writeable cartridge LSDJ is housed on. Of course, sample time is limited, but LSDJ lends one with enough space for many custom sample kits to please the people who prefer to upload their own rather than use the still very nice compilation of samples of classic drum machines that are originally contained in the LSDJ ROM file.

Vibrant user community

The user base of LSDJ is of course dominated by geeks, and by virtue of that, modifications of the physical hardware and new break-thinking tracking techniques routinely pops up. the most important ones are the homebrewed MIDI-interfaces which enables the LSDJ musician to sync up her or his little gray ones to their computer or hardware drum machines and synthesizers.

Other projects make it possible to example play the Game Boy sounds with a regular midi keyboard, modding your Game Boy Color to improve the sound and bass response in this later GB version. Or why not add a back light to your old grey brick? Neat!

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