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Son of Pedals


There has been a confirmed sighting of a copy of Son of Pedals. I haven't seen it myself but have been sent a photo taken on March 28th in London and it looks like someone has done an excellent job. The all black colour scheme makes it look like an evil twin! Evil Twin.


Son of Pedals has been up in Lancaster since August last year, where it has been going out on Critical Mass. It may have been used for other things but I am a bit out of the loop. I guess it is still working fine though, otherwise I would have been contacted. I recently got a call from someone who is building a clone and had a few questions about building the active crossover.


Since my last entry Son of Pedals has gone on lots of adventures without me. Just to mention a few, there was an anti-nuclear ride to Aldermaston, chasing the Olympic Torch through London to protest about the Chinese Government's ongoing violent oppression of the people of Tibet, and sneaking down into the concourse at Liverpool Street station to kick off the underground party on the last night before the alcohol ban came into effect. The system also set off from London to Brighton for the Carnival Against the Arms Trade but as I understand it the pilot lost control of the tandem and flipped the trailer. Being a sturdy beast, Son of Pedals survived with apparently minor damage but then never made it to Brighton because one of the cyclists on the ride, Marie Vesco, was tragically run down and killed by a car. On Saturday June 7th I went to London to collect the system and take it to a community cycling day in Waltham Forest and realised that there was a big hole in the cone of the bass driver. I bodged it with gaffer tape but after the event I decided to take it home for a refit, which required getting it on the train myself and then enlisting help to carry it over the footbridge at my home station. Since the bass driver was the non-standard 4 Ohm version of the SN-15B it was not possible to get it re-coned at short notice so I decided to buy a new driver and try to get the original one re-coned at a later date to have as a spare. It turned out that P-Audio did have a few 4 Ohm SN-15B's in stock as of a couple of weeks ago but interestingly they had sold them all to people who were ordering the exact same three speakers I used for Son of Pedals - it appears that a few people are in the process of building clones! So I ordered the very similar SN-15MB which they did have in stock in a 4 Ohm version and it was delivered the following day. When I took the old driver out I saw that it was in a far worse state than I had thought. Clearly battery acid had spilled on the cone, probably when it flipped over on the Brighton ride.

Anyway, I replaced the driver on Thursday, did a sound check, and took the system back down to London yesterday. When I got to the South Bank it was reunited with the tandem and DJ Eon arrived just in time to jump aboard for London Critical Mass. The Mass headed South this month and pulled up outside the Library in Brixton where Marie used to hand out free food every Sunday with the Brixton Reclaim Your Food group. One of her close friends took the microphone to say a few words, after which the whole Mass observed a minute silence. We then headed back North, crossed the Vauxhaull bridge and cruised along the embankment towards Parliament Square. The police brought the Mass to a standstill in Parliament square by attempting to enforce the "no loudspeakers" clause of SOCPA. After a twenty minute stand-off during which all traffic ground to a halt in the area, the pilot and DJ agreed to move off without music playing and then turned it back on once we were out of the square. We then raced off along The Mall and pulled up outside Buckingham Palace where the Mass ended in a mini rave. Doug was videoing and has put his footage up on the Internet Archive.


The fact that this page has not been updated recently does not mean that Son of Pedals has not been in action, but I have not been involved much myself. The last event I used it at was Reclaim Love in Piccadilly Circus on February 16th. There is a link to a video on the Reclaim Love website.


The soundsystem was at Lincolns Inn Fields in London this morning for a ride to Parliament Square to meet up with the National Climate March. I had been told that the tweeter had been cutting out so I took some tools along to try to do a repair. It turned out that one of the terminals on the tweeter had come loose and it had eventually come right off, resulting in an insulating washer being lost. On dismantling it I accidentally broke one of the connections on the voice coil so it was out of action. Without the tweeter the system would only have gone up to about 4kHz. Luckily I had a spare phono cable and was able to bypass the crossover and put the full signal into the mid-range channel of the stereo amp. That way we got frequencies up to about 7kHz and the built in high pass filter in the amp would have prevented really low frequencies getting to the mid-range horn (it is a lower order filter than the one on the active crossover circuit but it was good enough to avoid blowing the horn). So we had music on the ride, which helped keep spirits up in the cold wet weather. Despite the rain there were a couple of hundred people on the bike ride and about 10,000 on the march, which was just one of many demonstrations around the world, coordinated by the Global Climate Campaign to coincide with UN climate talks in Bali.


The system appears at least once in this report on today's demonstration against lack of cycle provision at the newly opened St Pancras international station.


Son of Pedals was used to support blockades at Aldermaston.


I helped build Pedals back in 2005 and have been on lots of events where it was used. This year I took on the job of designing and building a similar system for Bicycology, and the result was a system that is currently known as Son of Pedals. It made it's debut at the June 2007 Critical Mass in London, even though it was not quite finished.

Son of Pedals After a busy Summer I got the system back home for repairs and refurbishment. I made a few improvements, incorporated the new mid and top speakers that it was designed to use, and gave it a shiny green paint job. I also wrote up a page of design notes. Ian Gregory 2010