Randomatones

I almost never throw wood away. There is always something I want to build, refined or crude, that will serve some useful purpose, either as part of a Randomatones artifact (I have made several), or in the case of these pieces, some kind of supporting structure that will help me with an installation or a video shoot. These, probably with a bit more paint, will help me with a somewhat daring video I have planned for as soon as I'm ready. I've been meaning to do something like this for a while, and have already made a start on the electrics on one of the pieces that will provide lighting.

I do like it when a location scouting walk turns up something unexpectedly good. I have known about this place for many years, and dismissed is as probably not interesting enough to be worth checking out. With my re-emerging interest in the standing units, this place may a candidate after all. There's even a bit of graffiti, for my purposes a good thing in a place like this. It's possibly a bit huge, but that just means I need to be careful where to put the cameras, and might be able to turn everything up.

Visually, though I was somewhat lucky with the light at the time I was there, I especially like the pastel sandiness of the concrete and the ground in this picture, as if I've discovered a route to a hidden bunker in the desert. In fact this is a farm access tunnel under the M25 in Essex.

A return trip to the possible location I stopped off at a couple of weeks ago, this time with some lights and my cheapest most expendable video camera on a float, which I lowered into the water upstream, then waited for to emerge downstream, carried only by the current. Originally I thought it would only be a few minutes. I peered in from the downstream end and could see the lights but could not tell if it was moving or stuck. So I sat at the edge and waited hopefully. As I sat, watching leaves drift past, I estimated they were moving at around 10s per metre. With the culvert approximately 100m long, the float would take 1000s to pass through, a bit less than 20 minutes. Sure enough, 20 mins after dropping in at the top end, I watched it emerge from the bottom end, and scooped it out.

The video is very dark and not much to look at, except for a stunning moment where it passes under a circular inspection hatch moulding, like some giant Star Wars space ship moving overhead. The video is not important though, the purpose was to check the thing would make it through the tunnel without getting stuck on anything, before I start putting moderately valuable equipment in there.

The standing Randomatones in a tunnel under the A10 in Hertfordshire, where the Spital Brook (which I have visited before) flows under the dual carriageway and onwards to the pond in Barclay Park. Not that there was much flow. Despite recent rainfall, it has been so dry in the UK for the last six months, there was hardly any water in the tunnel. Where there was, I was able to stand in little more than a muddy puddle. I was able to put the Randomatones, and two camera tripods, effectively on dry land.

Video of the Randomatones appearing outdoors in the break between the outdoor and indoor performances on the Friday evening of the Woodbridge Ambient Music Festival. After so many videos of them under cover of some enclosure or other, often in otherwise complete darkness, it was good to see them under an almost cloudless sky at sunset.

I've been wondering about this place as somewhere to record/video. No way am I going in that culvert myself. Least of all, there are barriers and spikey deterrents everywhere to prevent would-be swimmers, or even accidental ones, but mostly because I have absolutely zero wish to. There's probably less than half a metre clearance in there, and there are bound to be monsters. But I do wonder what the acoustics would be like, and just because I wouldn't be going in, some free-floating equipment could.

There are potentially several other places that I've been thinking I could send unaccompanied Randomatones into, with audio and video recorded from separate units. This location has the advantage of a reasonable current to carry everything through in probably only a few minutes. The other places that come to mind are the many canal tunnels in the UK that do not allow unpowered craft, meaning I can't go in there and video with my boat. But sending Randomatones in to video themselves may work. The trouble with canals is they have very little current, especially now after a period of prolonged drought in England.

Delighted to have been invited by organiser Jan Pulsford two days before, I took the two standing Randomatones to the Woodbridge Cruising Club to feature in the first evening of the 2025 Woodbridge Ambient Music Festival. My "ambient lights", as Jan called them, ran for around half an hour in the balmy sunset while the outdoor music setup moved indoors.

When I built an 8-channel amplifier for the February 2025 installation, I used the TDA2030. This 5-pin chip is very simple to use, but is inefficient and wastes energy through a heatsink. I wanted to try a newer type of amplifier that uses Pulse Width Modulation (PWM) of a higher current signal to amplify more efficiently. Here I'm trying out the TPA3122D2 chip, a dual amplifier up to 15W per channel with a sufficiently high supply voltage (28V) and the right speaker impedance. I'll be using it at the standard 12V from an ATX power supply. Here I've built a working 2-channel amplifier, and will extend this to six channels.

I have had my eye on this location for a while now. For a long time this section of path on the City Mill River in Stratford was closed, while an extension to the railway bridge for the Elizabeth line was under construction. Earlier this year the water was clear, but I was not ready for the kind of shoot I wanted. Later in the summer it started to accumulate duckweed. Now, at the beginning of September, it looks like this. No matter, it will die back again, and I will eventually get round to making another floating video here.

Thinking about the electronics required to make a motor turn when sound plays through a Randomatone loudspeaker. It must rotate the motor in alternate directions and by the same amount each time, otherwise the connecting cable will become twisted. It would be very easy to send signals from a Raspberry Pi to do this, as it has all the necessary control ports. The trouble is, I'm not using a Raspberry Pi in the hanging installation (it would not play audio through the HDMI output properly). And even if I was, it would mean two extra control cables for each speaker, which I want to avoid, for the weight if not the expense.

Not much here except a couple of transistors to convert the feeble output of a motor control circuit, that I have yet to build, into something capable of driving a small motor. Once I get one complete control device working, I will build seven more and insert the motor between the hanging speaker and the suspending cable. The idea is to make the speakers rotate a little when sound plays through them.

Demoing the Randomatones software, as it was at the time of the February 2025 installation, now running on the innards of an old laptop.

Recorded using a new once-broken laptop, and superimposed onto spare footage from the Scout Tunnel shoot in Greater Manchester in February 2024.

Although it will be some time before I might be able and ready to do an installation here, in the place I still affectionately call The Steam Museum from when my son and I used to come here often, I did get to make a video just before the opening of their present exhibition by artist Jasmine Pradissitto. The shoot did not go well, mainly because I had only one device. I purposefully wanted to take the new smaller floating Randomatones on the tube, because they are supposed to be portable, sitting side-by-side in my cajon bag. I've taken them in that bag in car before (to a gig in Sheffield) and they were fine. But when I arrived at the Steam Museum, I discovered the red unit had turned itself on, including all its LEDs, which are several watts. The battery on the unit is very small, only 1.4Ah. By the time I opened the bag, the battery was just about dead. I had come without a charger to save weight, thinking I wouldn't need one. There was nothing I could do, but shoot with just the one unit. It did well, but I wasn't very interested in how it looked. So I did a bit multiplexing in the final video. The shoot was worthwhile though, as I now have an idea for fixed installation in this pool, if/when I have the opportunity.

Currently editing a new Randomatones video. Like the very first floating video, just a single device in this one. I did take two to the shoot, but coluld use only one.

Not wanting to leave my main laptop the next time I do a hanging Randomatones installation, I went on ebay and spent £15 on a computer that didn't work. No hard disk, no mouse pad, no battery and no power supply. Soon got it going. Superb machine. The one downside is that the power switch is minitature and flimsy. I would rather it not have one at all, but the ribbon cable connecting it to the motherboard is tiny and I'm not sure I can work out how to bypass it.

Back when my son was two (he's 15 now) and starting to like being taken on trips at the weekend, we discovered the Kew Bridge Steam Museum, immediately fell in love with the place, and over the next few years visited it many, many times. Having just done a successful Randomatones installation in a not dissimilar setting, I contacted the site, now called the London Museum of Water and Steam, to see if I might be able to do an installation there. I had a lovely reply from Richard Albanese, their project manager for sustainability-related presentations, who invited me over for a quick chat. I won't be doing anything there in the short term, but Richard did give me an idea for a one-off video which I think about a possible installation in the longer term. The video will not be in this room, which was in fact off-limits and under reconstruction when my son and I used to visit.

Video from last weekend's one-day installation at the Engine House in the Walthamstow Wetlands.

Back home now and reflecting on a sublime late-morning-to-mid-afternoon at the Walthamstow Wetlands Engine House earlier today. The sound was excellent in the Turbine room, and there was a lot more footfall than I expected, possibly the happy outcome of nature reserve meets fine weather. I am full of thanks to everyone wandered in, sat down for a while, stood and took pictures, or peered at the laptop and the electronics, and generally expressed curiosity and interest. I certainly talked to many of you! And it was a pleasure.

An update on recent progress towards the Randomatones installation in North East London one week from now. I'll be setting up a new 8-loudspeaker version of the Randomatones for one day only on Sunday 02 Feb 2025 in the Turbine Room, which is not normally open to the public.

Fiddling for the severalth time on what should be a set of straightforward comparator circuits that will light one of three LEDs depending on the input voltage which, to be fair, is the loudspeaker signal. So not straightforward DC. The cluster at the bottom left is a rectifier to turn it into DC, where the op-amp compensates for the voltage drop across the diode. The chip is an LM324 quad op-amp. Those first entered production in 1972.

The most important bit of what I've been building for the upcoming Randomatones installation at the Walthamstow Wetlands Engine House. This turns unamplified audio into some that can be heard through loudspeakers, of which I have eight of different sizes. I built and tested one, on the far left, and then built seven copies. I still haven't tested those yet.

I do talking videos occasionally but tend not to post them here as this site is all words anyway. Here's a couple of minutes on the Randomatones installation in North East London in a little under three weeks from now. If you've been there, there's a quick look in the Turbine Room where I'll be setting up a new 8-loudspeaker version of the Randomatones for one day only on 02 Feb 2025.

This is the Engine House at the Walthamstow Wetlands Nature Reserve, 2 Forest Road, London N17 9NH. On Sunday 02 Feb I'll be setting up a one-day Randomatones installation in the Turbine Room, pictured here from the outside. This afternoon I went down to take some measurements. Normally the Turbine Room serves as the staff room, the main café being at the other end of the building, but they also use it as a teaching room for school parties, and a functions venue. Although it looks like the smallest part of the building, the Turbine Room is large inside, and has great acoustic. As one of the staff told me today, that doesn't make it a good room to put large numbers of children in.

However, that makes it great place for Randomatones. I'm looking forward to unravelling what I now know will need to be well over 100m of cable for wiring everything up. And then taking it all down again at the end of the day.

A simulation of all 8 speakers playing together. So far I have only built one power amp, and one LED unit, so I videoed each speaker separately as the sun slowly passed behind some trees outside my west-facing window.

Changing over the speakers with the camera rolling nicely quantified just how fiddly it was to set everything up. The speakers will all have plugs/sockets, with the supporting picture-wire cable acting as a conductor (the ground), as it does here. Good bit of steel wire, hence why not. I took a few other notes on general adjustments to make. The high notes are too loud. This is normal, as higher frequency signals carry greater intensity, but I need to compensate for it in the synth stage. Something not obvious in the kind of cavernous tunnel I'm used to videoing the Randomatones in, but clearly noticeable here, is that the sound decay is too sudden. The linear amplitude ramp-down seems to cut off quickly. And it should go without saying I'll be tidying up the wires.