Echoplex Pre-amp Pedal Clone Project

PLX · Post by **PLX** » Mon Aug 16, 2021 1:47 pm

Mike Battle invented the Echoplex in 1959. His ideas were based on Les Paul's pioneering work with reel-to-reel tape machines to create "echo" or what was called early on, the "sound-on-sound" effect.

The Echoplex was used by Sun Records founder Sam Phillips on several of Elvis Presley’s first recordings. Other notable echoplex users were Chet Atkins, Steve Miller, Jimmy Page and Ed Van Halen.

Steve Miller's early "red face" EP-1:

Many guitarists learned that the Echoplex had an interesting and desirable tone altering effect when in bypass mode (not using the tape delay). Specifically, the solid state (EP-3) version used a TIS-58 transistor as a pre-amp on the input signal, which imparts a slight upper mid-range boost as well as a subtle frequency shift to the original signal.

Enclosure paint - 3 coats Rust-Oleum Hammered Copper. Parts sourcing:

PLX · Post by **PLX** » Mon Aug 16, 2021 1:54 pm

Project Schematic:

I have an NOS TIS-58 transistor for Q1 in this project, but I've also collected a variety of suitable replacement transistors, such as..

2N5484
2SK30
2N5953
2N5256
J113

The device can be powered with 9V ~ 12V which is then doubled via internal charge pump to 18V ~ 24V.

PLX · Post by **PLX** » Mon Aug 16, 2021 1:55 pm

Faceplate art mock-up:

Post by **RockyStar** » Mon Aug 16, 2021 3:40 pm

Good stuff man! That EP that Steve Miller has is dead sexy in that red.

PLX · Post by **PLX** » Mon Aug 16, 2021 3:48 pm

RockyStar wrote: ↑Mon Aug 16, 2021 3:40 pm Good stuff man! That EP that Steve Miller has is dead sexy in that red.

Right ?

PLX · Post by **PLX** » Tue Aug 17, 2021 12:21 pm

populating boards:

PLX · Post by **PLX** » Tue Aug 17, 2021 8:20 pm

Caps:

Post by **RockyStar** » Tue Aug 17, 2021 8:30 pm

Beautiful work my friend! You have a real gift with this stuff.

Post by **harddriver** » Tue Aug 17, 2021 10:07 pm

As I owned an actual EP3 echoplex it's not a myth on the effects of the preamp circuit on guitar tone. Zeppelin and EVH and many others...

I still use my Clinch and CHase Secret preamp still.... I think you will be pleased when you are done.

PLX · Post by **PLX** » Tue Aug 17, 2021 10:17 pm

harddriver wrote: ↑Tue Aug 17, 2021 10:07 pm As I owned an actual EP3 echoplex it's not a myth on the effects of the preamp circuit on guitar tone. Zeppelin and EVH and many others...

I still use my Clinch and CHase Secret preamp still.... I think you will be pleased when you are done.

Yeah, I have had the Badgerplex AC for some time, and it's one of those effects you just leave on all the time.

Not really a boost, just does some difficult-to-describe colorization of the tone.

I want to run two in series the way Jimmy Page and EVH did, to see what that sounds like.

The Truth (About Gear Forums)