Boards of Canada

In the original album description provided by Boards of Canada's label (Warp Records) the Yamaha CS-70M is mentioned as their "trademark" synth.

via Bleep

"We have five or six samplers, but my favorite by far is still the Akai S1000. It's an old tank now, and the screen has faded so that I almost can't read it, but I know it inside out. It's the most spontaneous thing for making up little tunes. It adds something to the sound - maybe the lower bit depth has something to do with that."

From an interview w/ Michael Sandison.

Boards of Canada is stated to use Logic Pro in a 2005 interview called "Emotional Abuse". "Given BOC's apparent allegiance to all things vintage, it should be no surprise that the duo eschews the use of software — including plug-ins, instruments or synths — aside from the occasional convolution reverb and Apple Logic Pro for arrangement duties." Given the date of the interview, it's very likely that they used version 7.

"Whether they're working separately or together, getting ideas down is generally a result of recording extended jams to tape on anything from a Tascam MSR-16 reel-to-reel to an old Revox recorder to a Grundig machine to an ordinary cassette. Remix, 2005"

On Boards Of Canada Wikia page it states that "BOC use the SH-101 extensively."

The back of an Akai S3200 can be seen in this photo taken during a live performance of Boards Of Canada.

Michael Sandison of BOC states in this interview they they "have a lovely new Taylor Big Baby steel-string guitar".

In this photograph capturing a live performance by Boards of Canada, we see a Casio CZ-101 synthesizer positioned on the drum stands in front of Michael Sandison. The CZ-101 is visibly linked to other equipment solely through a MIDI cable, indicating its probable role as a MIDI keyboard within this live setup. Strikingly, the synth's audio output remains unutilized during the performance.

Identification of the synthesizer is possible thanks to its distinctive side profile, featuring two audio jacks, a DC jack, and a guitar strap peg. The Casio logo is concealed beneath tape.

In these photos of live performances of Boards of Canada we can see how they use the Spirit Folio SX mixer, you can recognize the mixer due to: its shape, the logo, the number of audio inputs, and the fader that can be seen in the photo on the left. For the time in which these mixers were marketed everything fits.

On the Boards of Canada Twoism forum, user oliveoil22 demonstrated that Boards of Canada utilized the Ensoniq VFX-SD (or similar SD-1/VFX), as evidenced by videos where the user plays the exact preset on "Everything You Do Is a Balloon" from the 1996 EP "Hi Scores". In addition, one can hear the same "saw-o-life" preset layered in the song "Oirectine" from their 1995 EP "Twoism."