Good news!

We have delivered modification of power supply for our beta preamp. Now for its functioning you need stabilized power supply 9 V DC 500mA or higher.

We also managed to do polarity of supply like most effect pedals - Minus in Center.Never the less supply for the scheme is the same as in the previouse variant, with bipolar supply +/-15V.

We've built inside a voltage converter for this.Now there is no need to to purchase a special power supply 18 AC.