Tascam BP-L2 DR-1 Replacement Battery 3.7V 2100mAh

Tascam DR-1 / GT-R1 — 3.7V Li-ion Replacement Battery (BP-L2)

This 3.7V, 2100mAh Li-ion battery replaces the Tascam BP-L2 cell in the DR-1 portable digital recorder and GT-R1 guitar recorder. Both devices share the same battery bay, connector orientation, and BMS handshake protocol. Capacity is rated at 7.77Wh.

• DR-1 and GT-R1 compatibility: Both recorders run off the same 3.7V single-cell architecture and use identical BP-L2 form factor with the same three-pin connector. The BMS charge-termination voltage and communication signals are identical across both models.
• Bench tested on actual hardware: We cycled this cell through charge and discharge on the DR-1 platform. The BMS accepted a full charge without error flags, held voltage through sustained recording load, and cut off cleanly at the low-voltage threshold without dropping the file system unexpectedly.
• First charge before a recording session: Digital recorders write audio as a continuous stream to flash storage. A voltage drop mid-write corrupts the active file. Charge this battery to full before the first session — the DR-1's fuel gauge reads accurately only after one complete charge cycle.

Why the DR-1 stops recording mid-session and truncates the file

The DR-1 monitors cell voltage continuously during recording. When voltage drops below approximately 3.2V under load, the recorder halts the write process to protect the file system. If the shutdown is not graceful — meaning the battery collapses faster than the low-battery warning cycle — the current file is truncated at the last written block. A degraded original battery hits this threshold faster because internal resistance climbs with age, causing voltage to sag under the sustained draw of active recording and flash writes.

DR-1 shows "Low Battery" immediately after installing a new cell

A new Li-ion cell shipped in storage state typically sits between 3.5V and 3.7V — below the fully charged 4.2V ceiling. The DR-1 fuel gauge reads state-of-charge relative to a calibrated full-charge reference, so a partially charged new cell triggers a low-battery indicator. This is not a fault with the battery. Connect the DR-1 to USB or the AC adapter and charge fully before use. After one complete charge cycle, the indicator will read correctly.