  Accurate and precise measurements of spectroradiometric temperature are
crucial for many high pressure experiments that use diamond anvil cells or
shock waves. In experiments with sub-millisecond timescales, specialized
detectors such as streak cameras or photomultiplier tubes are required to
measure temperature. High accuracy and precision are difficult to attain,
especially at temperatures below 3000 K. Here we present a new
spectroradiometry system based on multianode photomultiplier tube technology
and passive readout circuitry that yields a 0.24 $\mu$s rise-time for each
channel. Temperature is measured using five color spectroradiometry. During
high pressure pulsed Joule heating experiments in a diamond anvil cell, we
document measurement precision to be $\pm 30$ K at temperatures as low as 2000
K during single-shot heating experiments with $0.6$ $\mu$s time-resolution.
Ambient pressure melting tests using pulsed Joule heating indicate that the
accuracy is $\pm 80$ K in the temperature range 1800-2700 K.
