Princeton Plexi 964


  • Model No. PP964

  • Push-Pull 6V6 Guitar & Bass Amp

  • Multi Power Level  25 - 12 - 6 Watts

  • 4-8-16 Ohm Speaker Switch

  • Dual Channel Princeton & Plexi Preamps

  • Separate Gains With Bright Switches

  • Deep Bass Switch

  • 3 Band Tone Stack

  • Classic Vibe Tremolo

  • Presence With Edge Boost

  • Post OT Line Out With Level

  • Tubes: 4 -12AX7, 2-6V6, 5AR4

  • Custom Upgrade Options


Guitarist Description:  This little amp really is amazing! The F channel cleans are very crisp and clear, great for country or blues type tones, especially with single coils...think Eric Clapton tones. The M channel will rock...tight dynamic high mids with smooth saturation.  Billy M. (Texas)



The FRENZEL  "Princeton Plexi 964"   is the newest version of our Mini Guitar amp series. It was "INSPIRED" by the  50's Fender Princeton...but it is a much more than a clone.  It has two separate preamp channels, one voiced like  the Fender Princeton Blackface  and one voiced like the Marshall Plexi.  The F and M channels have separate input jacks and gain controls which allows you to use an AB/Y switch to select one channel for Clean and one for Lead or  to combine the channels together for your own unique tones.  The voices are contoured by a modified Fender  style three band tone stack accentuated with a modified Presence control which has an "Edge" boost pull-switch to control the negative feedback for dynamic soaring leads. We also  added a Master control which allows you to control and shape the preamp and output stage overdrive tones.  A classic  vibe tremolo oscillator modulates the bias on the output stage  which uses   a pair of  push-pull 6V6's that produce the warm blues and jazz tones that made the  Princeton one of Eric Clapton's favorite amps. For those that prefer the Marshall rock tones, we  added a EL34/6V6 bias switch that allows you to use EL34's in place of the 6V6's. The  output transformer is a heavy duty  extended range type with 4-8-16 ohm outputs designed to produce with crystal clarity all the high, mid, bass the harmonics that your instrument creates. The output transformer feeds a passive three power level attenuator that provides a selection of 1/4, 1/2 or FULL power. When playing clean, this amp will faithfully reproduce what you put into it...and when you stomp on  will produce tones you have never heard before!  It works great with guitar, mandolin, bass, organ, piano, harp and strings. 

Standard Features:

  • Normal (Type F) Bright (Type M) inputs with separate preamps and Gain controls for the unique smooth Fender Princeton Blackface warm tones or the Marshall Plexi great high mid-tones....or you can use an AB-Y switch and create your own distinct tones.

  • Classic  Fender  style 3-BAND TONE STACK for extended flexibility in shaping your tone.

  • Master level control so you can crank the GAIN's up and overdrive the preamp without overdriving the output tubes.

  • Presence control  - used to adjust the high-frequency response and damping factor of the power amp section.

  • Unique NNFB "Edge" boost switch on the PRESENCE control that transforms the power amp section into a No-Negative-FeedBack style amp for soaring dynamic leads. 

  • Bright Pull-Switch on F and M Gains

  •  Deep Pull-Switch on Bass

  • Classic Bias Modulated Vibe Tremolo with foot pedal control.

  • Line Out - post output transformer LINE OUT with LINE OUT LEVEL control for recording or driving a power amp, Auto switched internal load to simulate speaker if speaker is  not plugged in. Inject great tone directly into the PA system with the Speaker Simulated Direct Interface.

  • Custom heavy duty output transformer for extended low frequency performance with 4 - 8 - 16 ohm outputs selectable by a rotary switch.

  • Three Power Level Selector Switch - Provides three power levels. 1/4 -1/2  FULL.

  • EL34/6V6 Bias Selector Switch - Allows you to use either 6V6 or EL34 power output tubes.

  • Standby Switch - Protects tubes from cathode stripping during warm-up. 

  • Tube Complement: comes standard with 4 - 12AX7,  2 - 6V6, 1 - 5AR4, but you can substitute 12AT7's or 12AU7's in the preamp and driver for different tones and overdrive sounds. You can also substitute EL34's  when using the EL34/6V6 Bias Selector Switch  in the output stage for different sounds....and yo can substitute a 5Y3 for the 5AR4 if you want more sag.

  • Electrical Specifications: 

  • Input Power  120 VAC 50-60Hz - 155 Watts Standard IEC plug-in three prong grounded power cord. (100VAC & 240VAC available. See Upgrade Options) 

  • Output Tubes - Class AB Push-Pull 6V6's - Fixed Bias

  • Output Power  -  20 watts

  • Output Power Selector Switch - provides three power levels. 1/4 - 1/2 - FULL power. 

  • Speaker Output Impedance - selected by switch 4-8-16 ohms.

  • Line Out Impedance - 10K ohms

  • Instrument Input Impedance - 1 Megohm

Physical Data: 

  • Open Chassis Dimensions - 12" Wide x 8" Deep x 2" High. (Add 6" clearance for tubes)

  • Weight - 15 lbs. 

  • Chassis - Heavy gauge aluminum with welded corners.

  • Retro Vintage Cage Mini Head  - heavy duty lightweight steel mesh cage provides protection and excellent ventilation for tubes. Comes with easy carry Fender style strap handle. Overall Dimensions - 12" Wide x 10" Deep x 10" High 

  • Rock solid point-to-point hand wiring with military style tie-wrapped wiring harnesses for long life and reliability.

  • DC on filaments to eliminate 60 hz hum.

  • Star ground system to eliminate induced current chassis noise.

  • Input and Output Jacks isolated from chassis for low noise, eddy currents, and hum.

  • Components - Only the highest quality parts are used including heavy duty transformers, low noise tubular polypropylenes capacitors, metal film resistors, Micalex sockets, Neutrik jacks. All parts are rated for commercial high use conditions. Wherever possible we use parts made in the USA.

  • Front Panel Controls - F Input Jack, M Input Jack, F Gain, M Gain, Bass, Middle, Treble, Presence/Edge Boost Switch, Pilot Lamp, On-Standby-Off Power Switch

  • Rear Panel Controls -  Power Cord Connector, Fuse, Output Power Level Switch, Line Out Level, Line Out Jack, Speaker Output Jack, Speaker 4-8-16 Impedance Selector Switch 

Upgrade Options:

These options allow you to  customize your amp to meet your special individual requirements.

EFFECTS LOOP -  pure tube buffered serial effects loop designed to perfectly match the low impedance solid-state pedal levels with high impedance tube levels..  Add $75.00. 

HIGH GAIN  JCM800 PREAMP - High gain stage added to both channels with pull switch on M Gain Control   to select between  low gain or JCM800  high gain.  Add $60.00​

DUAL RECTIFIER POWER SUPPLY - Power supply has both tube rectifier mode for smooth compression on peaks or a FRED  high voltage solid-state rectifier mode for sharp pick attack and dynamic bass. Switch on rear panel to select mode of operation. Add $50.00 

100 VOLT POWER TRANSFORMER - for operation outside the USA  where 100VAC line voltage is used. Add $55.00

240 VOLT POWER TRANSFORMER - for operation outside the USA  where 240VAC line voltage is used. Add $55.00