Friday, March 6, 2015

Boss DD2, 1984


I started a collection of vintage pedals, so here is my first acquisition, a Boss DD2 from 1984. This little 32-years-old lady was the first produced digital delay pedal, and almost the first all- digital stompbox ! This is an early version, with a serial number that corresponds to the "blue label" era (Unfortunately, the label was removed by a previous owner like on many old Boss pedals... ) The paint has scratches,  the knobs and boss pad are polished, jack inputs are a bit rusted… No doubts, this is an old pedal !

Boss DD2 194Boss DD2 1984

It is based on the chip that had been engineered for a delay in rack format produced by Roland at the time, the SDE-3000 . They were pretty lucky because it turned out that the chip fitted perfectly in the width of a boss pedal format! One can quickly see that the development purpose of the pedal is to compact all the components in order to fit tightly in the enclosure. Everything is very close, the capacitors are ceramics that are not very space consuming, mylar capacitors for the same reason, and separate PCB for the power supply, knobs and switch which are disposed vertically above the main PCB!  

The circuit diagram is also quite eloquent on the space savings necessary to achieve such a pedal with conventional components in a Boss-type enclosure:
Boss DD2 schematic
When opening the pedal, the microcontroller is very distinguishable because it takes the entire width of the pedal enclosure:
Boss DD2 inside 
The PCB layout is really 80s-style, with really curvy, almost psychedelic tracks! Real PCBs have curves! Inside, it is quite a mess, there are a lot of joyful wires going everywhere, and we can see the crowded components above de PCB:
Boss DD2 inside

DD2 production was stopped in 1986, then reissued under the DD3 name. Indeed, the circuit was exactly the same during a certain period. This was because the price of the chip diminished a lot, so in order not be considered to overprice their products, Boss reissued the DD under a different name! 

Thus, there are DD3 that are technically identical to the DD2, which are called "long chip version" due to the size of the microcontroller. Then, the microcontroller was changed by a small size one, and the assembly was made more automatic with less wires to assemble. Today, the DD3 is using SMD components and a double-sided PCB, which solves entirely the space-saving problem. Today, it is still possible to find it for a reasonable price, so if you want the first numeric pedal in your collection, buy one now !



How does it sound?
Well, the sound is really the classic sound you would expect from a digital delay pedal: a very precise repeat of your input signal with no degradation. I heard that somehow this delay should sound more "analog" than others DD from Boss. Surprisingly, I have to admit that this is true! Sure, you can clearly hear that this is a digital delay, the degradation of the sound is absent, but still, the repeat are less clear / bright than the input signal. Apparently, this is due to the analog nature of the repeats that are sent back into the microcontroller. I will record samples as soon as possible !

0 Comment