Stereo Memory Man – more clock madness

This one is a bit convoluted but kind of cool. Well, nerdy-cool.


I’ve owned a few Electro Harmonix pedals over the years, including a couple of Stereo Memory Man with Hazarai™s (to be referred to as the SMMH hereafter). This makes it one of the only bits of gear I actually cared enough to replace after it broke (to be fair, I broke it myself). I don’t actually use it much as a straight-ahead delay;  it’s the looper functionality where it really shines.

Here are a few of the crucial features which make the looping section unique:

  • Varispeed. There are plenty of loop pedals which enable you to play the loop at half or double speed, but on the SMMH this is via a knob, so you can go anywhere inbetween. Doesn’t seem impressive on paper but you can get all sorts of weird pitching effects. It’s like a tape machine with a speed control; i.e loads of fun.
  • Feedback control. Probably the most awkward to explain, but this controls how much of the existing loop remains when you overdub. At halfway, the volume of the existing loop is halved, so you can create slowly evolving patterns where the existing layers of sound subtly fade out as you add more. Trippy.
  • The footswitch. This will divide people but I am used to the fact that the SMMH uses a ‘soft’ switch for the tap tempo and overdub control. It also works in a unique fashion- you hold the switch for as long as you want the loop to last, and the loop starts playing when you lift off. This might be totally counter-intuitive to those used to other pedals; the majority have clicky footswitches which you tap once to start recording, and tap again to stop recording and start playback. The SMMH works for me because it is exactly like using the sustain pedal on a piano. More on this later.
  • The tap tempo still works in loop mode, and speeds up or slows down the current loop without changing the pitch. You could either use this to subtly change the speed if you’re trying to keep time with other musicians, or you can go to extremes and get some weird grainy time-stretching effects.

Basically the one thing that the looper lacks is the ability to sync to anything; recently I stumbled across a mod on the internet which adds just that.

Nav’s blog is a trove of interesting stuff, and there are 3 posts about the various modifications all of which are explained in excellent detail. I chose to do two of them- adding the clock output and an external footswitch socket, so that the pedal can remain on a desktop and still be foot-operated. The switch I use is a piano-style sustain pedal which works exactly as well as you’d think.

Here’s a pic of the mods (a bit messy but you get the idea). What’s really cool is that you’re basically deriving the clock from the tempo LED, which is something I’d never have thought to do.

So having tapped the clock, I naturally wanted to turn it into midi clock to drive the rest of my gear. Here’s where I ran into a couple of issues; the clock that you get is effectively 1 pulse per quarter note, or 1ppqn* (see appendix). So I tried it out with my Sonic Potions LXR, which has a clock input section on the trigger expansion board. It worked, but sadly there’s a bug in the LXR firmware which causes skipping, which quickly began to annoy me. So instead I decided to go back to the Volca Keys, which I’ve found to be a good way of converting analogue clocks to midi. The glaring problem with the Volca is that the clock resolution doesn’t match – it expects 2ppqn which means that the Volca, and its subsequent midi clock output, run at half speed. Still with me?

In the intervening period, I got hold of an Arturia Keystep, which does support 1ppqn clocking. Except I found it to be a bit fussier than the Korg in terms of what clock signals it works with. Driving it directly from the SMMH directly was a no-go, after a lot of failed attempts. So my final set up is as follows:

SMMH clock out –> Korg Volca ‘sync in’ –> Korg Volca Midi out (clock)—> all other midi gear

With most of the stuff I own, there’s usually an internal resolution, so for example I can run the sequencers of some of my gear at ‘double’ speed to correct for the ‘slow’ clock. You can similarly change the quantise resolution on the LXR to compensate, but it’s a bit of a faff when programming. Hopefully the LXR firmware will get an update and then I’ll be able to dispense with the Volca and shorten the chain a bit.

That’s probably enough about the technical side- what is it like in use? Well it’s a weird process, in that it involves going about things backwards. Usually if I’m trying to make a loop, I’d probably start with the drums or a click track then layer things up on top. With this system, you start with the loop layers then hope that the clock lines up over the top! The key to success is playing in time with yourself, and trying to count the beats as you play (again, see appendix). After a bit of practice it does get a lot easier, and the beauty of it is that you can wipe the loop and record something else if you’re not happy with it. Then reverse the whole thing, change the pitch, do some time stretching and the beat will stay in time.

Let’s face it- this is certainly a niche use for this pedal, but if you’re into modulars and voltage control, there are any number of further applications. Finally- don’t attempt these mods unless you’re confident that you can do them without wrecking the pedal – the pcb is so firmly wedged in the enclosure that you’ll probably have to drill holes with it still in place.


*Appendix: Is it really 1ppqn? Well, sort of. Basically the pedal generates a tempo, always in 4/4, based on the length of time you hold the ‘loop’ footswitch for. It takes some getting used to, but after a while it feels almost as though the pedal ‘detects’ the timing from your playing, although in reality it’s probably just dividing the length of the loop by 4 (or 8, or 16). The fact that the pedal calculates a tempo in the first place was very surprising to me, but it makes sense when you consider the tap-tempo functionality. Either way – this is a seriously over-engineered pedal; and is a testament to the skill of designer David Cockerell, who is a legend in the world of electronic music. Here’s an interview with him if you don’t believe me:






3 thoughts on “Stereo Memory Man – more clock madness

  1. Hi, very inspiring post! I’m used to my SMMH loops being the basis of my creation process and would love to slave midi device to it. What were the issues with using the keystep? i was thinking of picking one up for this mod. Kind regards.

    • Hi Clayton. The only mode that works in terms of clocking the Keystep from the SMMH is when you set the Keystep to receive ‘1 Pulse (Korg)’ as the clock signal. This means you still have the problem of drum machines running at half speed, but you can at least run sequences at lots of different resolutions. I like the Keystep and have found it useful in lots of other situations so I’d say definitely get one.

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