Mic Preamp

The SPL Crescendo uses SPL’s 5th generation SUPRA op-amps to create a 120-volt power rail, resulting in more 10dB of additional headroom and 3dB less noise. It also makes it extremely difficult to overload the preamps.

Housed in a 3U rack, each of the mic preamps includes an analogue VU meter, -10dB calibration switch, +48V phantom power, polarity reversal switch and a -20dB input pad. A gain control is also included offering a range of 52dB. The preamp offers 18dB to 70dB of gain which is reduced to -2dB to 50dB with the -20dB pad switched on.

Differential amplifiers at the input stage are designed with transistor pairs which are consolidating in a dedicated housing. Transistors are precisely matched and thermally coupled to offer superior common mode rejection. Discrete op-amps are used at the output stage and are designed to drive long cable paths. Active Servo circuits have also been employed to eliminate DC voltage. Finally, the built-in toroidal transformer power supply is shielded using a special Mu-metal sheet to avoid any electrical interference.

On the back, are eight inputs and eight outputs over XLR as well as eight additional outputs via D-sub (DB25) for easy connectivity.

SPL Crecendo Manual