Here is a closer look at the Titan Boost by John Hollis. The circuit uses an op-amp to boost and buffer the input signal. This is fed into an inductor that steps up the voltage at the output.
The amplifier is built around a TL072 dual op-amp IC1_A and IC1_B.
The first stage, IC1_A, is a non-inverting amplifier with a gain of 3. Determined by R3 and R4.
Non inverting gain:
Gain = 1 + R4 / R3
3.2 = 1 + 22K / 10K
The output of the first stage feeds the top of the inductor, 42TM006, the input of the second amplifier stage IC1_B, through R5.
The second amplifier, IC1_B, is an inverting stage with a gain of -1. The gain is determined by R5 and R6.
Inverting gain:
Gain = R6 / R5 * -1
-1 = 10K / 10K * -1
This stage outputs an inverted version of the first stage. The output feeds the bottom of the inductor.
The two op-amps are set up as a push-pull amplifier across the secondary coil of the inductor. One op-amp pushes current through the coil while the other pulls current from the other side.
An AC signal through one coil of an inductor produces an electromagnetic field. A magnetic field generates a flow of electrons in a nearby coil. The AC signal across the left, secondary, coil produces current flow in the right, primary, coil that mirrors the signal on the left.
The 42TM006 transformer has two coils. The secondary, the coil on the left, and the primary, the coil on the right. The primary coil of the inductor steps up the voltage on the secondary (1K) coil by roughly X10. The increased number of windings in the primary coil increases the voltage generated in primary coil. This is where the volume boost of the Titan Boost comes from.
The idea here finds it’a way into a few stomp boxes. The classic Octavia uses a The idea here finds its way into a few stompboxes. The classic Octavia, and other octave pedals, use a transformer. A few Ring modulators use transformers. The new Yamaha Revstar has an onboard, passive boost, that uses a transformer.
These transformers were available through Mouser.com. It looks like they don’t sell them any more. At the time I wrote this I was able to find 42TM006 and LT44 on eBay:
There might be other options out there.
All of this said the question becomes how could you use this in a stompbox?
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