Active/Passive Retro-Fit for P-Style Basses
The P-Retro is simple but flexible active/passive bass preamp equaliser which offers huge tonal variation to one of the most
popular styles of bass of all time, without the need to permanently modify the instrument itself. P-Retro features two stacked
knobs each with a pull switch, class A FET input stage and a high quality relay for pure passive bypass. Power is provided
by an internal rechargeable battery.
The normal volume control becomes the Volume/Tone Stack and works in exactly the same way as the P style bass original
controls, passing the passive signal directly to the jack. When the volume control is pulled up, the active circuit is switched
in, post passive tone control, and adds 2.5dB of gain, with a flat response. Additionally, the upper knob allows either a mid
boost, or a combined bass/treble boost. The lower knob sets the variable frequency points for either mode.
Summary of features for the P-Retro:
• Two Stacked knobs, both with Pull Switches.
• Original pure P style bass controls fully retained via passive path, using a high quality relay bypass.
• Class A FET input stage.
• Flat response active setting.
• Variable frequency mid boost mode.
• Variable frequency combined bass/treble boost mode.
• Deep boost switch with four frequencies, set via internal switches, and Bright option.
• Deep boost level set via internal preset trimmer.
• Rechargeable internal Li-Pol Battery, giving up to 40 hours use per charge.
• Battery charging is achieved using an AC/DC Adaptor, which plugs into the jack.
• Auto passive bypass if the system runs low on power.
• Easy to fit using screw terminals, with no solder connections to the P-Retro.
• Instrument can be returned to stock condition since there are no physical modifications to the bass.
• P-Retro Active circuit board approximate dimensions: L50.0 X W27.0 D15.0 mm (2.0” X 1.07” X 0.6”)
• P-Retro Volume/Tone & Li-Pol battery approximate dimensions: L50.0 X H29.0 X D19.0 mm (1.6” X 1.15” X 0.75”)
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