pkpk614350
New Member
Initially, I intend to divide the hold circuit into 3 parts which are the pre-amplifier, tone control and output stage. I found that the output stage need 7 volts to work but the power is just 4.5V battery. If using the op-amp to increase 4.5 volts to 9V is nearly impossible becoz the output of the op-amp is restricted by the power supply.. Would you guys give me some advice