Every generation has an instrument which defines its sound, and for those whose formative musical years lie in the 1980s, a very strong contender to the crown is the Roland TR-808 percussion synthesizer. Its sounds can be recognized across a slew of hits from that era and every decade since, and though the original instrument wasn’t a commercial success it remains accessible through sample packs, emulations, and clones. The 808 was an all-analogue device that didn’t use samples, thus [Mark Longstaff-Tyrrell] has been able to reproduce its distinctive cowbell sound with reference to some of the original circuitry.
It shouldn’t come as too much of a surprise to find that the circuit is refreshingly simple. The trigger pulse is converted into an envelope which controls a pair of oscillators. The mixed output passes through a bandpass filter to create the distinctive sound on the output which you can hear in the video below the break. The circuit is recreated on a breadboard with the only concession to modernity being a microcontroller taking the place of the Schmitt trigger oscillators in the original.
Altogether it provides a fascinating insight into the synthesis behind a classic sound, and gives us an increased appreciation for the design skills of those Roland engineers who created it. We’ve looked at the 808 before a few times, including an explanation of the famous faulty transistors which contributed to its sound.
That headline sounds suspect, but it is the most succinct way to explain why the Roland TR-808 drum machine has a very distinct, and difficult to replicate noise circuit. The drum machine was borne of a hack. As the Secret Life of Synthesizers explains, it was a rejected part picked up and characterized by Roland which delivers this unique auditory thumbprint.
Pictured above is the 2SC828-R, and you can still get this part. But it won’t function the same as the parts found in the original 808. The little dab of paint on the top of the transistor indicates that it was a very special subset of those rejected parts (the 2SC828-RNZ). A big batch of rejects were sold to Roland back in the 1970’s — which they then thinned out in a mysterious testing process. What was left went into the noise circuit that gave the 808 its magical sizzle. When the parts ran out, production ended as newer processes didn’t produce the same superbly flawed parts.
This is an incredible story that was highlighted in 808, a documentary premiered at SXSW back in 2015. The film is currently streaming on Amazon Prime (and to rent everywhere else) and is certainly worth your time just to grasp how seminal this drum machine has been in hip hop and several other music genres.
For modern product developers, betting your production on a batch of reject parts is just batty. But it was a very different time with a lot fewer components on the market. What worked, worked. You do have to wonder how you stumble upon the correct trait in an obscure batch of reject parts? Looks like we’ll be adding Ikutar Kakehashi’s bookI Believe in Music: Life Experiences and Thoughts on the Future of Electronic Music by the Founder of the Roland Corporation to our reading list.
If you spent the 1980s hanging out at your local record store, and you don’t have a hankering for spandex and bouffant rock-god hairstyles, the chances are you’ll have more than a few pieces of electronic music from the period in your collection. The proliferation of electronica during that era came through the arrival of relatively inexpensive mass-market digital polyphonic instruments, edging out the sounds of monophonic analog synthesisers for a subsequent generation to rediscover in a later decade. Individual instrument models became icons and entered the musical vernacular of the day, the Ensoniq Mirage sampling synthesiser, the Yamaha DX7 FM synthesiser, or the Roland TR-808 drum machine.
It is the Roland TR-808 that inspired today’s subject, the MR-808 robotic drum machine, from [Moritz Simon Geist]. A percussion sequencer featuring real instruments all built into a cabinet styled to resemble a huge Roland 808. Originally built as a performance instrument, but since reinvented as a piece of installation artwork that visitors can program for themselves.