Jimi Hendrix’s Roger Mayer Octavia

Jimi started using this pedal around January 1967, after meeting Roger Mayer – an acoustic engineer working for the British Admiralty who as a hobby designed and built effect pedals for guitars, when they were still virtually unknown.

In case you’re unfamiliar with the functionality of the Octavia pedal, in Roger’s own words Octavia “produces a sound that is an octave higher than the note you are presently playing.” The effect is somewhat subtle, but if you watch a few YouTube videos, you should be able to tell the difference. A good starting point is this ProGuitarShop Demo video.

Jimi meets Roger, ‘Are You Experienced’

According to Roger Mayer, he first met Jimi at the Bag O’ Nails club in central London – probably around January 1967. This time frame is important to establish because by that time Jimi had already released Hey Joe, and was about to release Purple Haze and Fire. The tracks were mostly finished, but upon learning about the Octavia, Jimi decided to overdub the solos.

I first met Jimi a few days after my 21st birthday, after one of his shows at the Bag O’Nails club in Soho, London. […] He invited me along to a gig the following week, which is where he first listened to the Octavia backstage on a small amp. He was so impressed and excited with the new sounds he invited me along to the Olympic Studio later that week to overdub the solos on his second release—”Purple Haze”—and “Fire.”

Hendrix, Page, and Standing Out in a Crowded Effects Market: A Conversation with Roger Mayer

According to Roger, Jimi used an early version of Octavia on those two tracks, one of which had a separate fuzz box driving it, and after the tracks were recorded, this version of the pedal was never used again.

This Evo1 unit used germanium transistors and a ferrite transformer and also had limited drive capabilities. It was used in the recording of “Purple Haze” and “Fire” with another custom driver in a separate enclosure that also used germanium transistors. This driver was placed in front of Evo1 to give enough drive and extra EQ to satisfy Jimi and produce the sound you hear on the recordings. After the Purple Haze / Fire session recordings, Evo was never used again in its original form and I consigned it to the trash bin.

Roger Mayer – Octavia

The rest of the tracks on Are You Experienced are somewhat of a mystery in regard to whether they feature the Octavia effect or not. If you have a good pair of speakers and a good ear, give it a listen and try and see if you hear it anywhere else. I can’t seem to catch it anywhere myself.

Axis: Bold as Love

Roger and Jimi started collaborating more closely on Axis, and at that point, Mayer was pretty much responsible for setting up effects for Jimi. According to Roger, this version of the Octavia was somewhat different from the one used on Purple Haze, as Rogers continually made modifications and improvements.

Later in 1967 after we began recording sessions for the second album “Axis Bold as Love” which used the latest Evo of Octavia on several tracks and if you listen carefully the clarity and detail of the Octavia effect was much more defined. Of course, at the same time, I was updating, building and customizing the distortion units to complement the latest Evo of Octavia being now used.

Roger Mayer – Octavia

The effect was used on a number of tracks from the album, including Machine Gun, Little Wing, One Rainy Wish, and Little Miss Lover. This is all according to Roger; more detailed research will be done at some point but we’ll leave it here for now.


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