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Actives: Battery voltage increase.

Discussion in 'Pickups & Electronics [BG]' started by Rockin John, Jun 18, 2001.


  1. There have been a number of threads on this general subject. Questions like: 'Can I up the battery voltage from 9 to 18?' Or '...from 18 to 27?' Or....'from 27 to 36?' are usually asked.

    I've answered a few of them with much the same response: take great care because you might end up wrecking your actives. So I thought I'd produce a kinda check-list of things you really should know before you attempt upping the battery voltage.

    1) THIS IS VITAL: Will the chip(s) withstand the new proposed voltage?
    Most op amp chips will withstand 30 Volts (+ and - 15Volts) across them and some even higher.

    2) Will the circuit design accomodate more batteries?
    Single battery (only 9V) systems will be more likely - NOT DEFINITELY, JUST MORE LIKELY - to be OK with 27Volts, than 18Volt systems going to 27Volts.

    3) Will you be able to switch multiple batteries on and off?
    1 or 3 battery systems are likely to be easier than 2 or 4 battery systems.

    4) Then comes the practical business like fitting more batts into the bass, and so on.

    How to find this out? Ask the manufacturer of the actives is the best way: assuming they'll tell you 'cos some like to keep circuit details secret. If you know a friendly electronics man ask him to take the part numbers from the chips so he can refer to the Tech data sheet for the answer. Get the circuit schematic from the manufacturer if you can (this will greatly help with Q2). If not it can be reverse engineered directly from the circuit board if you know someone who can do it.

    There's loads more on this subject but I've given the basics.

    Hope this helps.

    Rockin John