The SP-23 external speaker has been designed for use with Icom basic amateur radio transceivers, but especially the IC-7400 and the new SDR IC-7300 transceiver. It includes built-in high-pass and low-pass filters to obtain the maximum audio characteristics of the received signals. Four separate audio network filters equipped for maximum control of audio characteristics of received signals High pass filter 1: Cuts audio output frequencies of 300 Hz or less. High Pass Filter 2: Cuts audio output frequencies of 600 Hz or less. Low Pass Filter 1: Cuts audio output frequencies of 2.4 kHz or higher. Low Pass Filter 2: Cuts audio output frequencies of 800Hz or higher. Similar height and depth dimensions of the IC-756PRO2. One headphone jack, two audio input jacks allow connection of two amateur radio-style transceivers.

Features
Features	Metal construction 5.75 x 4.25 x 11.2 inches 3.6 lbs. (145x111x283mm 1.65 kg). The bottom panel of the speaker features a pull-out tilt stand if you wish to angle the speaker. A single audio cable is supplied with a mono mini plug at both ends.