AK-2 Pro World Scale Tuning is a MIDI device that converts a wide range of synthesizers to a specific Scale Tuning. It can adjust the pitch of each note in the octave (C to B) to  -64 to +63 cents.

Kelfar AK-2

Key Benefits

AK-2 Pro can be connected simultaneously to two synthesizers via the two MIDI_OUTS (Primary and Secondary)
AK-2 Pro works on most MIDI synthesizers ( i.e. Yamaha, Roland, Korg, Ketron, and Kurzweil)
AK-2 Pro works on most Midi synthesizers that support Pitch Bend midi data Monophonic and *Polyphonic (NEW FEATURE)
Transpose buttons for Korg Triton series, Fantom x, Korg Pa series, Ketron, Yamaha, and Keyboards with GM/GM2/XG logo

*Polyphonic in Multitimbral

Supported Instruments/Models (FIRMWARE VERSION 2.8):

Korg Pa80, Pa50, Pa60, Pa55Tr, Pa1&2x (Pro), Pa800, Pa3x series, Pa500, P500 ORT, Pa600, Pa600QT, Triton Classic, Karma, Studio, Extreme, Le, Tr, Micro X, X50, Kronos series (with firmware 2.3 and up), *M3 series, *Oasys, *Trinity, Korg Z1, and Korg Prophecy.
*Trinity series works in all modes, except the MOSS mode.
Roland Fantom S, X, G, AX-Synth Shoulder Synthesizer (with firmware 2.6 and up), and models with GS logo
Yamaha Motif ES/ MO (preset scale only – Arabic 2) and instruments with XG logo, Tyros/Psr series, Motif XS (Voice,Song,Pattern), and Motif XF (Voice,Song,Pattern), GENOS
Ketron VEGA, SD5, SD1, and AUDYA series
Kontakt with a provided script – Kontakt Script (Native Instruments)
Kurzweil K2600 and K2000 series
MOOG Sub Phatty and Sub 37 (AK-2 FIRMWARE 2.7 and up)

World Scales Support (-64 cents to +64 cents)

Equal Tempered Tuning System
Micro Tuning System
Turkish ( Byselik, Rast, Ussak, Nikirz, Saba, Huazm, Siga, and more)
Byzantine (Modes 1,2,3,4,5,6,7,and 8)
Arabic (Bayati, Rast, Siga, Huseini, Hijaz, amd more)
and more…


1. Display Screen – 2 digits
2. Transpose buttons “Coarse Tune/General Midi 2/Yamaha XG/Roland GS/Ketron” per instrument
3. User Programmable Scales 9
4. Recall the preprogrammed User Scales in realtime
5. Standard mode – sending System Exclusive Messages
6. Universal mode – 4 different ways to detune an instrument (i.e. Pitch Bend)
7. Standby button
8. Two Midi_Out ports
9. One Midi_In (Enabled for the Universal mode)
10. Pa80/60/50 port
11. Supports Korg, Roland, Ketron, Yamaha, Kurzweil, Ayoub Module, Kontak 2/3
12. User Scales are adjustable -64/ +64 cents
13. Total of 14 buttons
14. Firmware updates for future upgrades
15. GUI Interface to program your own User Scales and performing firmware updates
16. Dimensions 5.8 x 3.2 x 1.8 in / 14.7 cm x 8.1 cm x  4.6 cm (metric)


1. AK-2 Pro Setup Guide (PDF)

2. AK-2 Graphic Interface for Windows (NEW) (zip)

3. Latest firmware version 3.2 AK2_MAIN_032.bin (zip)

4. Kontakt Script (Native Instruments)

5. Korg M3 EXPANDED converted set to work with AK-2 Pro (.zip)

6. Korg M3 Guide – MAKE your set/sound to work with AK-2 Pro

7. Roland Fantom G Guide – MAKE your set/sound to work with AK-2 Pro


DISCONTINUED… AK-4 Pro is coming soon!