This is one of the coolest and most fun musical tools I own!


The PO-20 Arcade is, like most PO's, a tiny sequencer with 16 adjustable sounds pre-loaded. There's lots of great options for a pocket operator, but I think this one is especially popular because the chip-tune "bleep-bloop" sounds really match the aesthetic of these devices. It has a few drum sounds, and lots of different bleeps and classic arcade sounds, as well as 16 effects, chords, and patterns. I'll list each of these at the bottom per the manual.

Overview and build:

This device is sleek, durable, and functional. It's very small, and thin as an edge. The 2 AAA batteries it runs on are the largest part. It's display is fun and informative, and it has a small speaker just under the screen that actually gets louder than I expected. Like all PO's it has a break off hanger that makes it look even more like a cheap calculator, and a small folding stand made of metal wire. It's components are exposed which I thought was going to make me nervous, but I think it was meant to be used without the case (which seems needlessly expensive imo) and does't feel too fragile. Looks great, and makes cool sounds right away. Perfect as a source on inspiration, adding sounds to a drum machine or synth (awesome to sync with a Korg Volca), add texture and bloops without dragging and dropping .wav files or presets, or honestly just to play with!


So how does this whole thing work?

The basic principle of the Pocket Operators is that you can sequence the sounds, chain chords and patters, and modulate the patterns and sounds live.

Playing Sounds:

just press one of the buttons! Once pressed use the two encoders to control the sounds. Usually encoder A is pitch and B is waveform

To select/change sounds:

Hold down sound and press the key

Sequencing:

You can add to the sequence live or program it in step-wise.

Manual enter:
While the Sequencer is stopped (press "play") you can enter write mode (press "write", recording box will appear in the lower left corner) and enter the selected sound any of the 16 steps. When a sound is selected in write mode the LED indicate which step that sound is loaded into.
Select another sound to enter its steps in and press play to hear back.

Live enter:

While the sequencer is playing but not in write mode, you can hold down write and press any sounds you want. They will be automatically added to the sequence and quantized to match the swing setting. While it's playing back you can select a sound and modify it using the encoders by holding down the write button as if you were entering in new steps.

Note: For melodic sounds (most of 9-16) this is how you can add a real melody! The encoder allows you to scroll through notes in the scale of whatever chord has been selected. Not easy to be accurate with pitch as you're playing a knob, but it still will get you the melody you're looking for if you practice.

BPM:

Pressing BPM alone toggles between 3 different preset tempos, Hip-Hop 80, Disco at 120, and Techno at 140. Handy. You can manually adjust BPM by holding it and using encoder B, swing can be adjusted (+ swing only) using encoder A.

Chords:

Pretty straight forward, hold down "chord" and it will display using the 16 LEDs which chords are being used. When the sequence is playing, the current chord will be bright, while the other chords will be dim. To select a chord, simple press pads 1-16. It will begin playing at the top of the next 16 step sequence in the new key.

Other chords?
You can chain together something crazy like 128 chords in sequence. Simply press which chords you want in what order while holding down "chord". You can repeat the same chord over and over (i.e. Dm Em G G G Am) in a chain which will loop back to the beginning of the sequence.

FX:

This button is used to modify everything that's playing out of the PO-20. To choose an effect, hold down FX and press 1-16. Each one has it's own little iconography on the display screen.

The top row allows you to solo different sets of sounds playing, see above for details.

Second row is an automatic filter cutoff effect. Low pass or high pass, either sweeping up and down or static.

The last two rows (9-16) are time-related effects. Most of these are "one-shots" that will turn off automatically when after you engage it. These are actually some of the coolest effects on here imo because it allows you to very quickly switch from a static beat to something with stutter, a build-up, or break. Especially cool when used in conjunction with the filter effects. It literally sounds like a classic DJ drop if you do it right.

Notable mentions: FX 16 is a unique bonus that does like a rising arp sound all on its own?
FX 15 this is one time effect that will stay on until you turn it back off (chord+pad again). It's super cool.

Pattern:

To select a pattern, hold "pattern" and choose one of the 16 buttons just like chord mode. Any lit number has a pattern in it.

To clear the pattern you currently have selected, press "chord" + "pattern".

Same idea as chord, you can chain a bunch together and skip around all you want. However, the chord data and the pattern data are not mutually exclusive as far as I can tell, meaning that any single pattern is subject to the overall chord structure, as opposed to each pattern containing a chord chain of up to 128 chords. I could be wrong about this, I'll have to check.

Other features:

1. Side-chain/Drone:

Simple but it makes all the difference. If you hold "chord", encoder A will change the volume of the drone. This is a very pretty sounding chord that will play for the duration of the whole pattern and change according the chord. It fills in a ton of space and does not sound over bearing.
Best part: encoder B adjusts the level of side-chain for the chord. Links it to the kick drum sound only I think, and can make the drone subtle or create a pull on pumping effect. So cool.

2. Fade Out: if you press "FX" + "play" it will fade the entire pattern chain out SLOWLY. It's actually very cool, good way to wind down or stop the device in a live setting with out the jarring needlescratch of hitting all stop.

3. Step multiplier: in write mode you can select a step 1-16 to re-trigger during the sequence either 2, 3, 4, 6, or 8 times. Hold down the step you want to re-trigger and press BPM to cycle between these 5 re-trigger types.

Global Edits (abridged)

There is no real power off switch, it will automatically enter power saving mode (appears as an "insert coin" graphic) after not being touched for a while. If you press "sound" + "write" it will technically power it off and save whatever new patterns you've made in case the batteries die.

"sound" + "BPM" will show battery status out of 100

You can supposedly set a clock and alarm on it right when you turn it on but I haven't bothered. Sound cool though!

For Volume, while holding BPM, buttons 1-16 become a volume slider, with 16 being the loudest. Simply press which button to change volume and it will slowly fade up or down to match it.

Sync:

You can use CV to link the PO-20 to other pocket operators or anything else with CV capability to make the PO the master or slave clock. To do this the PO's have sync modes SY0-SY5. These modes aren't like MIDI channels, they basically indicate where the PO is in the control chain.

To toggle between these hold "chord" and press "BPM".

SY0 is just internal, no syncing.
SY1 means the PO-20 will be the "master" or first in a chain.
SY2 means it will receive CV data and adjust tempo based on the input it gets.
SY3-5 indicates which order among other PO's or CV connected devices this PO will fall into.

Thanks for reading! Check out Red Means Recording or Cuckoo on Youtube they both are awesome and do great reviews that cover basically everything I just did.


Sounds:
1. Bass 5. Tom 9. Arpeggio 13. Lead
2. Kick 6. Blip 10. Melodic Arp 14. Vibrato
3. Snare 7. Hardsync 11. Falling Arp 15. Portmento
4. Hi-Hat 8. Noise Fx 12. Octave Arp 16. Echo

Chords
1. Dm 5. F 9. Am 13. A
2. Em 6. G 10. C/A 14. B/A
3. Esus 7. C/G 11. Dm/A 15. C
4. E 8. E/G# 12. D/A 16. D

FX
1. solo chords
2. solo chords + lead
3. solo drums
4. solo drums + bass
5. lowpass slow sweep
6. lowpass fast sweep
7. highpass filter
8. highpass sweep
9. fill-in
10. fill-in (fast)
11. retrigger
12. retrigger (fast)
13. glitch
14. glitch (fast)
15. blinds
16. rising arpeggio