The Mackie SRM450 is a great speaker but I think it be better to have a separate mixer. Here's why:
1. Ability to plug in up to 8 line-in devices like 4 mics, a keyboard, a cd-player, a cassette deck for recording, etc.
2. You can apply more Mixer DSP effects over the whole system or on just the devices you want. You can tailor your sound very precisely. The Mackie 808S and the Yamaha EMX800ST are stereo mixers that can really take advantage of our stereo keyboard's abilities.
3. Upgrading - If you want to upgrade speakers or the mixer later you can without sacrificing the whole system.
4. Price - The price for good speakers and a stereo mixer is about the same as just buying two SRM450s (running $750 to $799). The Mackie C300/C300i is nearly identical to the SRM450 but without the built-in mixer.
Two SRM450s will cost $1598. The Mackie C300/C300i speakers cost $389 each. A Mackie 808S Stereo Mixer delivers a lot of power (1,000 watts into 4 ohms) and costs $799. So, for $1578 you can buy the mixer and two C300 speakers. You'll have more power, more useable inputs, (yeah, one more piece to carry but each piece is lighter), and can be easily upgraded as you need (when the next generation of speakers hits the market).
Well, probably nobody will agree with me but that's where I am right now. If Mackies are too expensive, you could go with a Yamaha EMX860ST stereo mixer ($549) and two Yamaha S112-IV 12-inch speaker cabs ($259 each) for a total of $1069. Then upgrade the speakers to Mackie later when you've got more cash.
I'm expecting some money to come my way sometime before Xmas. If it does, then I'm going for the Mackie system. If it doesn't, then I hope I can afford the Yamaha system before the end of the year.
Sorry, didn't mean to write book . . .
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