Boss Micro Studio Series Vol.1, 1986:

3 Different Phasing Modes Let This Phaser Create a Multitude of Effects

A new generation RPH-10 Phaser with 12-stage phase-shift circuitry and recording studio quality sound. According to the mode selected, 3 completely different effects can be produced. Mode I (6 stages) is for soft and light phase-shifting, while Model II (10 stages) creates deeper phase-shifting all the way from the lows to the highs. Mode III (12 stages) is for when a sharp and intense phasing effect is required. Apart from the basic RATE, DEPTH and FEEDBACK controls, the RPH-10 is also equipped with a MANUAL control to adjust the center frequency around which the phase shifting occurs. With this control, it becomes easy to find a setting that is suitable for a particular instrument. A custom IC, newly-developed, is utilized in the phase-shift circuitry to produce phase-shifting which is exceptionally smooth. Although phasers usually tend to get noisy as the number of stages increases, the RPH-10’s built-in noise reduction system ensures a wonderfully clear sound.


  • MODE: For selecting one of the following 3 modes. Mode I provides 6-stage shifting for a mild phasing effect, while Mode II offers a deeper effect due to 10-stage shifting. Mode III is for very intense and powerful 12-stage phasing.
  • MANUAL: This will select the center frequency of the phase-shifting and helps to match the phase-shifting to the type of instrument used.
    RATE: For adjusting the speed of the phasing effect. Turn clockwise for increased speed and counterclockwise to slow it down.
  • DEPTH: For adjusting the depth of the phasing effect. Turn clockwise for a deeper-sounding effect and counterclockwise for shallower phase-shifting.
  • FEEDBACK: For controlling the amount of feedback signal to create a stronger phasing effect.
RPH-10 Phaser

Point Of Performance

Having 3 different modes, the RPH-10 allows the user to produce a very wide array of effects, from the sharp and intense to a soft and light effect. Effectively employing these 3 modes will allow the RPH-10 to display its full potential. In Fig. 1 you see the setting utilizing Mode I to produce a phasing effect which is shallow and natural-sounding. An ideal setting for electric piano, one that delivers an open, wide type of sound with a slight emphasis on the highs, you ‘II find it often used by Richard Tee. Mode II is used in Fig. 2 to create deeper phase shifting, an effect that really puts synthesizer lead solos in the spotlight It’s also effective for guitar backing where muting is used. By setting RATE to a slightly lower position, you have the perfect sound for reggae cutting. With Mode III, a deep and very intense phasing sound is effected by taking full advantage of the 12-stage phase circuitry. It’s a setting that really adds sparkle to synthesized strings with the RATE control lowered just a bit.

Trick & Shock

Using two RPH-10 units, you can produce true stereo phasing with the modulation of the two units being mixed. First, connect the 2 units through the MODULATION BUS jack. Set the RATE lower r and the DEPTH greater on the first unit. For the second unit, use opposite settings. The result is the complex modulation effect as shown in the Fig. below.