The SRP400s are the second smallest model from Sonodyne's lineup of budget-minded compact active monitors and feature the 4.5-in. woofer option. The full lineup features five versions, starting at a 3.5-in. woofer and going up to an 8-in. woofer. Quick detail: the SRP in the model name stands for Sonodyne Reference Professional. The front panel features the power switch and blue power light as well as the volume control. The volume control ranges from mute to +6dB and has a odB mechanical centre detent.The rear features recessed DIP switches for both bass and treble tilt, allowing for a -2, -4, or -6dB cut at 100 Hz for the bass and a -2dB cut at 4 kHz for the treble frequencies. On the back is a standard IEC AC power connector with both a TRS and an XLR connector for balanced input and lastly, the fuse. There are th readed M6 mounting holes - two on the back and four on the bottom -for attaching to an optional wall mount bracket with rubber plugs inserted in the bottom mounting holes for use as the feet, which provide a nominal amount of decoupling.
Price, Eric (2015) Sonodyne SRP400 Compact Active Reference Monitor. In: Professional Sound, Vol. 26, No. 2, pp. 24. Available at https://openmusiclibrary.org/article/847880/.