Commutators — Standard and PRO
The X-Series commutators are two models of rotating joint for the tether between an X-Series headstage and XDAQ: the Standard, a passive mechanical commutator, and the Commutator PRO, motorized with active torque compensation.
What a commutator does and when a preparation needs one is under that entry; this entry compares the two models.
The Standard commutator is mechanical and needs no power. An off-center tether attachment converts the animal's rotation into the torque that turns the rotor, with animal-side cable management built in. It passes up to 256 channels per cable from a record (XR) headstage and 32 from a stim-record (XSR) headstage, with the DAQ connector on top and the headstage connector below, in a 42 × 42 × 87 mm body with a 3.2 mm mounting hole, sized for closely spaced animal racks.
The Commutator PRO replaces the passive mechanism with a low-noise motor and continuous active torque compensation, so the animal supplies no force. Rotation is sensed from an animal-side gyro/IMU on a 34 AWG bundle under 1 g, or from a rotor-side Hall encoder where no sensing mass can go on the head. It passes 256 XR or 64 XSR channels per cable, has up to four Neuropixels ports and up to nine GPIO lines, and can stimulate through a passive probe while recording a Neuropixels probe in the same session. It connects over USB-C to XDAQ or an imec-compatible system, validated with imec 5 m and Kontex 1 m cables, and takes Intan headstages and controllers through adapters. Options are a 5 mm fluidic or optical-fiber passthrough and a 6-hour battery pack. It is 99 × 105 × 150 mm and 800 g, mounted by a bottom thumb-screw or a 1/4-inch camera mount.
The PRO adds stim-record channels, Neuropixels ports, GPIO and the removal of the tether's pull on the animal, at the cost of size, mass and a power connection; a preparation in which the passive commutator turns freely enough does not need it.
Typical values
| Standard | passive · 256 XR / 32 XSR channels per cable · 42 × 42 × 87 mm · no power |
|---|---|
| PRO | motorized · 256 XR / 64 XSR · up to 4 Neuropixels ports · 9 GPIO · 800 g · plug-in or 6 h battery |
| PRO sensing | animal-side gyro/IMU or rotor-side Hall encoder |
| Compatible | X-Series headstages; XDAQ CORE2, ONE+, ALL-IN-ONE |