RB-Pro (Rockabilly Preamp)
Type: preamp
Features: 2 channels; package includes bridge pickup (SH951) and fingerboard pickup (SH2500); runs on 9V battery or wall adaptor; built-in tuner; phase;
bridge channel: EQ (Bass, Mid, Treble), Subsonic, fingerboard channel: Low cut, Treble control

BCP3 Electric Bass Cable Preamp
Type: preamp
Features: bass, mid and treble controls, gain control (in the battery compartment), shape switch for different sounds, on/off switch, integrated battery compartment

www.shadow-electronics.com

Sadowsky Bass Preamp
Type: preamp
Features: input 330K Ohms, treble/bass boost controls, footswitch active/passive/mute, XLR out, battery or AC adapter powered (low battery indicator LED)

www.sadowsky.com

D-Bass 210
Type: combo amp
Features: “FFP” with Active Speaker Control technology, “COSM®” preamp models (including Modern, Vintage, and Super Flat), Tube Logic function (produces the fat and natural compression of tube amps), 4-band EQ with dedicated Tweeter Control knob, Passive/active input and dedicated piezo input (!), neodymium-based speakers (2 x 10″ + tweeter), Output Power 400W (160W + 160W + 80W), BI-AMP Structure, balanced out, tuner out, headphone out, effects send/return, line out, casters

www.roland.com

SSB-1 Sound Shaper
Type: preamp
Features: 9V battery powered, volume/bass/trebel controls

SSB-2 Sound Shaper
Type: preamp
Features: mixed signal technology (combining digital control from an embedded processor and high precision audio analog circuitry), 5-band graphic equalizer (optimized to cover the bass and cello ranges), phase shift

Each band (and volume control) has 256 discrete adjustment points that are set at the touch of a pushbutton.  All settings are precisely repeatable upon each power up and all are saved in non-volatile FLASH memory on power down under control of the system processor.  On power up, all settings are automatically retrieved.  Additionally, the SSB-2 is capable of storing up to 8 sets of player settings.  Using a keyed pushbutton sequence, you can store and recall each set from memory at anytime.”
Both preamps are designed to mount directly to the pickup output jack.

www.rjp-enterprises.com

PMB-1 Professional Master Blender
(no longer available)
Type: preamp, dual channel/blender
Features: Instrument channel (10Meg Ohms) + auxiliary/microphone input (820K Ohms) with 9V phantom power, stereo input, phase switch; gain/bass/mid/treble controls, 2 x 9V battery or AC adapter powered

www.raven-labs.com

AP13 Acoustic Processor
Type: preamp, dual channel/blender
Features: piezo input, microphone input with phantom power, Low cut filter, 7-band graphic EQ, Pan control, phase invert switch

www.rane.com

Acousti-Q Tube preamp/blender
Type: tube preamp, dual channel/blender
Features: piezo input (10Meg Ohms), microphone input (3,2K Ohms, 12V phantom power), notch filter, semi-parametric midrange EQ, phase reversal, brilliance + bass controls, effects loop, AC adapter powered

Mini Brain
Type: amp head
Power rating: 120W@4 Ohms
Features: high gain/low gain inputs, Bass/Middle/Treble control, triple bright control-switch

Mini Brute I, II, III, IV
Type: combo
Power rating: 120W@4 Ohms
Drivers: Brute I/II: 12″ speaker
Brute III/IV: 15″ speaker
Features: high gain/low gain inputs, Bass/Middle/Treble control, triple bright control-switch, Reverb (Brutes II, IV & Mega Brute), 2 Inputs (High & Low), Effect loop
Size: Brute I/II – 15 1/2″H x 14″W x 10 1/2″D
Brute III/IV – 18 1/2″H x 17″W x 10 1/2″D
Weight: Brute I/II 24 lbs.
Brute III/IV 28 lbs.

The Polytone amps has been introduced in 1968. They are still popular among double bass players, but also jazz guitar players often play Polytone amps. The Mini-Brute III is provided with a 15″, the Mini-Brute I with a 12″ speaker.

www.polytoneamps.com