Which Octaver?

[ICBM]

Just remember if you get an OC2 run it with a 12volt power supply as it was intended ( the boss ACA power supply). It tracks better and holds notes longer before it loses track with 12volts.

Or bypass the drop resistor.

If you run it on a non-isolated daisy-chain with other 9V pedals it's automatically bypassed anyway.

The OC-2 is one of the ones where it makes a big difference. I think think this is one of the reasons for the perceived difference between some Japanese and Taiwanese versions of the same pedal - which is real on some (eg DS-1) but not on others. I can't tell any difference between the Japanese and Taiwanese OC-2 when both are ACA models. I think the last PSA ones possibly do sound different, but I haven't directly A/B'd them.

[imported_Dannyboy]

Or bypass the drop resistor.

If you run it on a non-isolated daisy-chain with other 9V pedals it's automatically bypassed anyway

Where abouts in the circuit is the resistor ? I've never quite got into this 12V vs 9V for Boss pedals.

[ICBM]

Where abouts in the circuit is the resistor ? I've never quite got into this 12V vs 9V for Boss pedals.

It's in series with the negative connection from the power jack to ground (via the input jack), along with a diode.

http://www.hobby-hour.com/electronics/s/oc2-octave.php

R17 (470) on the left hand side, with diode D3. To give true 9V operation you need to bypass both the resistor and the diode, but I prefer to leave the diode since it acts as a reverse polarity protection without having to rely on D1 to clamp it (often dying in the process and leaving the pedal non-operable until changed). The diode cuts about 0.7V from the supply voltage.

NB, the tip and ring connections on the input jack are shown the wrong way round on that schematic .