The J-RETRO 01 is designed to fit directly into standard “Jazz” style basses without modification, including a PP3 battery, in most cases. Its high quality circuit uses three stacked knobs and includes an active blend circuit plus a 3 band equaliser with bass, variable frequency mid, treble and bright function.
The J-RETRO comprises an Active 3 Band EQ with Sweepable Mid. Its design ncludes limited Passive Control. Designed to fit Standard Jazz Basses – 4s & 5s.
A very gentle built-in contour gives immediate colour without detracting from the basic sound of any bass.
The active blend circuit prevents the loss associated with many passive basses where, when both pickups are up full, the signal from one pickup feeds into the other and vice versa.
However, a switch is included to allow a passive equal mix of both pickups. A second switch – basic “get-you-out-of-trouble” passive mode is included in case the battery dies in crucial circumstances, and this mode allows some useful settings too.
EASY TO FIT, NO ROUTING OR MODS TO MOST J STYLE BASSES.
A STANDARD PP3 BATTERY FITS UNDER THE PLATE IN THE STANDARD CAVITY IN MOST CASES.
HARDWARE OPTIONS: Chrome, Black or Gold. (Can be mixed by special request)
Specifications
BASS & TREBLE
TREBLE (+12dB @ 3 kHz, -12dB @ 1kHz)
BRIGHT (+8dB @ 7kHz)
BASS (+15dB @ 50Hz)
MID LEVEL & FREQUENCY
BOOST/CUT (+/- 12dB)
FREQUENCY (150Hz – 3kHz)
User Manual
Installation & Operation
Videos
John gives a complete walkthrough on how to install a J-Style preamp.
What they Say
The J Retro preamp arrived yesterday and I was able to install it in about 30 minutes. I did solder up the battery box on my bass (holds 2, so I wired it for 18v) for use with the preamp. My gosh, this tone is what I’ve been searching for with this Mike Lull Jazz bass!
The J-Retro transformed my Geddy Lee Jazz and the pickups were well balanced. They really are great preamps. My home made bass which uses a status graphite jazz neck, seymour duncan p/j and a badass bridge is absolutely perfect and your circuit / bass beats the pants off a few high level instruments I’ve had!
Hello John, The J-Retro already arrived today and I just popped it in my bass within a few minutes. It sounds great.
I’ve purchased one of your J-Retro 01 preamps for my fretless ’98 Mexi Jazz, and installed with no problems.  I’m using Lindy Fralin split-coil pickups, with a 5% overwound bridge pickup. Oh my…I think this just became my favorite bass! Those Fralin pickups have all sorts of growly tones buried in there, and the preamp brings them out VERY nicely.
It arrived about 12 and I installed it after lunch. Thanks for such prompt service. Your retro pre-amp gives an amazing range of tones for me to play with, like having a totally different bass, but still a Jazz.  Can’t wait to see how it sounds in the band mix in a couple of days.
 I wanted to take a brief moment to thank you for creating a high quality product that delivers what it promises. I recently upgraded my Fender American Jazz V with some Nordstrand pickups and one of your J-Retro preamps. I am absolutely blown away at how good it sounds with only very minimal settings.
