PBX Preamplifier

Plexon’s PBX Preamplifier can operate either as an important component of the Multichannel Acquisition Processor (MAP) Neurophysiology System, or as a stand-alone hardware component for use with third party data acquisition systems.

The PBX Preamplifier (PBX) includes spike boards for isolating the spike action potential signals, field potential boards for isolating the low-frequency field potential signals, and wide-band boards.  These boards are designed to process the signals from depth electrodes in the brain or peripheral nervous system, or from EMG signals.

The preamplifier is scalable from 16 to 128 channels. It offers both fixed reference and software-programmable reference selection, and low noise for improved SNR recordings.  Depending on the gain in the headstage (typically 1x or 20x), the PBX will be configured such that the overall fixed gain is 1000x (e.g. 1x in headstage and 1000x in preamp, or 20x in headstage and 50x in preamp).

Plexon PBX Preamplifiers have excellent common mode rejection capability of both fixed reference electrodes and up to five recording electrodes selected within software to be used as reference electrodes. The programmable referencing feature on the PBX is selected within the RASPUTIN suite of control programs for the MAP System.

Analog Programmable Referencing is a particularly valuable feature for recordings from freely moving animals. Artifacts caused by sudden movements, chewing, grooming, etc., can be effectively eliminated by selecting a recording electrode with artifacts (but no spike signals) to be the reference electrode for a subset of other electrodes nearby. In this way, the common artifact signal on both the reference and recording electrode is removed in analog circuitry before A/D conversion.

The PBX can be purchased and operated as a stand-alone hardware component for use with third party data acquisition systems.  It is also a standard component of the MAP System.  A Plexon Sales Engineer is available to provide additional information and to answer your questions.

The table below outlines selected technical specifications regarding the PBX Preamplifier. Click through if you need additional information on the MAP System. A Plexon Sales Engineer is happy to talk with you about any of your questions.

Features Specifications and Options Remarks
Channels 16 to 64 per PBX box PBX Preamplifiers can be combined to achieve higher channel counts.
Programmable referencing Up to 5 programable analog reference channels
Common mode rejection >100dB at 0-60Hz
LFP analog low-cut filter 0.07, 0.7, 3Hz (user selectable with jumpers)
LFP analog high-cut filter 8kHz – 3rd order Butterworth
Spike analog low-cut filter 150Hz – 1st order
Spike analog high-cut filter 8kHz – 3rd order Butterworth
Spike analog low-cut filter 50x, 250x, 1000x, selectable
Wideband analog low-cut filter 0.07, 0.7, 3Hz (user selectable with jumpers)
Wideband analog high-cut filter 8kHz – 3rd order Butterworth
Input referred noise 3μV rms with 3Hz low-cut, 8kHz high-cut, 8000x gain
Gain 50x, 100x, 1000x For use with various Plexon headstages
Power to headstage +/- 2.5V default It is possible to modify the board to achieve +/- 5.0V
Dimensions 4.0 x 2.5 x 8.5 inches
Input connector 26 pin male Harwin connector per 16 channel amplifier board

Although customizable at the time of order, the standard filter and bandpass settings are listed below.

Features Low-cut Filter Type Low-cut
Filter Value
High-cut Filter Type High-cut
Filter Value
Programmable Referencing
Spike 1-pole 150Hz 3-pole 8kHz Yes
LFP 1-pole 0.07, 0.7, 3Hz
(user selectable with jumpers)
1-pole 170, 300, 500Hz (user selectable with jumpers) No
Wide-band 1-pole 0.07, 0.7, 3Hz
(user selectable with jumpers)
3-pole 8kHz No
EMG 1-pole 100Hz 2-pole 4kHz