The op amp with the highest gain-bandwidth product ... place can upset the loop stability and turn your amplifier into an oscillator. Bandwidth isn’t the only measure of speed though.

[Jule]’s little analog synth uses a single IC for both the oscillator and the amplifier — a TL072 op-amp. The rest is made of purely discrete components. [Jule] says those momentary switches ...

(Strictly, the op-amp should be a comparator; it’s used as one.) C1 would normally be switched for different ranges, with R1 varied for tuning. Figure 1 A typical relaxation oscillator with an ...