Little Lightning Devices MEMORIAL Modulated Reverb

This one spent a long time on my breadboard. I started with a schematic for the Belton Reverb module that has been used by many DIY builders for years now, however I wanted to make my own that I could modify and adapt to something a little different. I spent a long time in a rabbit hole trying value changes at a few obvious points before deciding it might also be fun to add an LFO to give the effect some movement. So, I did and here we are. Long decay reverb. Subtle modulation. Runaway feedback or haunting oscillation with a momentary switch. Oh and the option for tails or standard buffered bypass.

The effect is quite straightforward as far as a typical reverb circuit. Analog dry path with a wet path through the modified reverb circuit, with some filtering and a mix control. I included a feedback loop along with a parallel momentary switch to allow for quick access to higher feedback settings. The two are interactive, so the momentary switch will allow for oscillation if feedback is high, or simple extended decay if set lower. Get some nice ghostly echo in the reverb tail, or feedback blasts if you want to get some attention.

The damp (low pass filter) control tames high frequencies on the reverb path only, which is helpful to rein in sharper feedback or make the effect more subtle. It also helps tame the LFO warble if you prefer a more subtle modulation in your reverb tail.

I’ve left the LFO control for the rate only, slow speeds add nice subtle movement, and fast rates help give a more obvious vibrato/pulse to the reverb tail. If you don’t want modulation on your reverb, then Memorial might not be for you – however the modulation is not that extreme and adds some nice colour, keeping the reverb sound present and alive in the mix.

Memorial is a buffered bypass effect; it requires power to pass signal. I’ve included a tails mode (internal switch) which does allow for some reverb signal to remain present when in bypass. It’s more obvious at high mix levels, but this allows for the momentary feedback to oscillate even when bypassed. If this is not preferred, it can be switched to standard bypass with the internal dipswitch.

Like all Little Lightning Devices, Memorial is hand built in very small batches right here in Canberra Australia.

Controls:
Mix – sets the level of Reverb.
Feedback – feeds the output of the reverb path back into the input for longer decay and oscillation
LFO – sets the rate for the modulation on the reverb
Damp – a low-pass filter on the reverb path to help tame hi-frequencies and rein in decay / feedback – also helps tame the modulation effect in the reverb tail.

Switches:
Bypass – bypasses the reverb
Feedback (momentary) – increases the feedback level, oscillates at high settings
Tails (internal DIP switch) – sets the bypass mode (tails or straight bypass)
Note – with tails on and the mix high, a tiny amount of reverb signal will be noticeable as there is some bleed in tails bypass. If you don’t like this I’d recommend not using the tails mode.

Power required - 9v DC (centre negative). Do not run at higher voltages.