About
YAMAHA PTX8 Percussion Tone Generator is a 12-bit PCM drum synthesizer with deep synthetic features.
YAMAHA PTX8 (1987)
28 samples in seemingly 256KB ROM - no hats and cymbals, but with various kick and snare variations.
Here are .mp3 sound examples of PTX8. The demos are recorded without external effects and overdub.
Sequence 01 (144KB)
YAMAHA RX5 is the base model of PTX8. It's a highest-end drum machine at that time. Many synthetic features were added, while older RX series couldn't even change the pitch of the samples. YAMAHA also advertised that RX5's 'Normalized 12-bit' engine has 16-bit-equivalent dynamic range, though I don't know what it exactly means.
RX5 has 12 individual outputs, and can use the pads to play pitched tones.
WRC01 - 04 ROM cartridge series can be used in both RX5 and PTX8.
YAMAHA RX5 (1986)RX7 is the updated version. It has 1.1MB (9Mbits) sample ROM, though the cartridge slot is omitted. No individual outputs, and the EG is simplified to one decay parameter. LFO is added to modulate the pitch and the volume. Some voice effect with pitch shift delay is added. It's made without a DSP - just eats the polyphony by layering voices.
YAMAHA RX7 (1987)Difference in editing between PTX8 and RX5/7: PTX8's advantage is that you can change the waveform with each pad. In RX5/7, you have to start all editing from the preset pad voice. That is, a kick is always a kick, and a snare remains snare forever. With PTX8, you can make a Hi-Hat from a snare sample, and yet use the sample for snare in the same kit. That makes it more like a synth, and kit-making is easier.
YAMAHA ED10 is an analog drum synthesizer with a pad. It seems to have 1OSC-1SubOsc-1Noise with a ring modulator, a resonant filter, and auto bend. ED10 was made as the pad for PTX8.
YAMAHA ED10 (1987)RX8 is the last model of RX series. It uses 16-bit samples, but sounds still lo-fi and retains RX feel. Synthetic parameters are simplified, though still has the reverse function.
YAMAHA RX8 (1988)RX5, RX7 and PTX8 are the rare drum synths with short-looped drum sounds. Similar looped sounds are found in Technics SX-KN2000, a GM-compliant arranger keyboard with synthetic editabilities.
Technics SX-KN2000 (1993)
Deep Synthesis: Home3.29.2007