The Yamaha EMX312SC powered mixer just may be the model you need.  It features dual 300 watt power amps and the added advantage of one-knob compression on mono channels. The Yamaha EMX312SC mixer is built to the same standards of sonic performance and rugged reliability that make Yamaha the first choice for live sound applications from schools to stadiums around the globe. Yamaha is a leader in the field of professional live sound for a very good reason: they deliver the sound and performance that the pros demand. The EMX312SC powered mixer is no exception.

One-knob Compression on Mono Channels
All four monaural mic/line channels on the EMX312SC feature built-in compressors that can help to bring vocals to the front of the mix, give your guitars extra smoothness. The compression also delivers more authoritative bass sound, and generally refines your mix in a multitude of ways. These one-knob compressors are simple to use, too. There's no need to juggle multiple attack, threshold, makeup gain, and other controls - just set the COMP control for the amount of compression you need

Feedback Channel Location
FCL (Feedback Channel Locator) indicator LEDs at the top of each channel light if the corresponding channel goes into feedback, so you won’t have to fumble around searching for the channel that needs adjustment.

SPX Digital Effects
The EMX312SC features a selection of 16 top-quality Yamaha SPX effects – including reverb, echo, chorus, flanger, phaser, and even distortion – that can add the final touch to your live presentation. Yamaha SPX digital effects are widely recognized as being some of the finest available, and the effects provided in the EMX mixers live up to that reputation.

Built-in Graphic EQ
Graphic equalizers are provided for both the main and monitor channels, so you can effectively control feedback or tailor the sound the match the room and program material.

Stand-by Mode
When you're done with a set simply engage the stand-by mode to mute all mono channels while leaving the 2-track inputs active for background music playback while you're taking your break.

12 Inputs
The Yamaha EMX312SC offers a total of 12 input channels – four for monaural microphone or line input, plus four pairs that can function either as monaural microphone inputs or stereo line inputs – providing you with a versatile mix of input capabilities for a wide range of applications. If you need only microphone inputs you can use up to eight mic channels. Or if, for example, you want to play recorded background music during breaks (that’s one stereo channel), and you have a keyboard player with a stereo output keyboard (that’s one more stereo channel), you still have six mic/line inputs. If you use all four stereo pairs to handle stereo line sources you have four channels available for mono mic or line input.

This is a very versatile system that can adapt to your needs. High Power For Main and Monitor Speakers The EMX312SC doesn't skimp on power with 300 watts per channel. The mixer also features a power mode switch that lets you use the two power channels as a stereo amplifier, or you can use one of the channels for the main speaker(s) and the other to drive monitors with a separate monitor mix set up via the channel MONITOR controls.

Durable, Lightweight Design
The EMX312SC powered mixer offers the ideal combination of outstanding sound performance and easy handling. It's lightweight and features conveniently located handles for maximum carrying comfort. It's built tough to withstand the rigors of use on the road.

Yamaha Speaker Processing
Yamaha Club-series speakers are fine performers in their own right, but with Yamaha Speaker Processing built into the EMX312SC, you get extra-smooth highs and enhanced low-frequency output.