The MFX are what is termed ‘insert effects’ whereas the reverb and chorus are ‘send’ effects.

Basically, the reverb and chorus (which can also be delay instead) are the usual type of effects you get with a mixer, where every channel has a ‘send’ and the ‘return’ from the effect is blended back into the mix.

But the MFX effects are the type where the entire signal from the Part (or multiple Parts) is run through the effect, or ‘inserted’ into the signal path. So, for instance, a guitar amp simulator would affect the entire signal, not just get a portion of it ‘sent’ to. However, there’s a certain degree of crossover because some effects (like the MFX choruses and reverbs etc.) have a balance control where you can mix the effected signal with the dry…

But in practice, you tend to use the send effects for stuff most things need like a bit of reverb and either chorus or delay, and then the MFX for things one specific Part needs, like a tremolo for a Wurlitzer piano, or a phaser for a Rhodes, or an amp sim for an electric guitar, etc..

If the MFX Part Link parameter is on, calling up a factory sound will load a factory default MFX setting for that Part (but you only have two for all four Keyboard Parts, so you will have to decide which needs them on a per-Performance basis… normally they are set to be on UPR 1/2). You can learn a lot about the MFX by taking a look at their settings, turning them off to hear the difference, and also messing with the two MFX adjust sliders (the brown ones) which usually are set to adjust something on the fly in the MFX.

Although you CAN route multiple Parts into one MFX, be aware that there is no separate wet/dry mix for each Part, so if for instance you sent both UPR Parts to a phaser, you couldn’t have a little phaser on one and a lot on the other. One mix for the entire MFX. And there’s no ‘stacking’ of MFX’s… you can’t run the output of one MFX into the input of another. So you couldn’t for instance run through the phaser into an amp simulator. This is why you’ll see some ‘combo’ effects like PHZ>DIST which do both effects in one MFX, but usually with less control and less quality (as one MFX is having to do both effects).

I know it seems a bit complicated at first, but do some playing around and you’ll get it quickly. A great place to find out what you can do is the styles themselves. There are three MFX dedicated to just the Style/SMF section (accessible through the Makeup Tools) but virtually none of the factory styles use them! So you can experiment putting different MFX on different Parts and just listening to what they do while the style plays…

Try a phaser on a Rhodes. Try a flanger on a synth sound, mess with the parameters. Try an Exciter on a brass section to make it pop out of the mix. Sky’s the limit…

Or try my favorite use of the MFX…

I HATE sampled distorted guitars! That’s not how distorted guitars sound… notes aren’t distorted individually and then combined. Each combination of notes you play and each dynamic you play at distorts in a different way with a real guitar and amplifier. So try this… find a rock style with a distorted guitar Part. Using the Makeup Tools, change the distorted guitar to a clean one (Strat, Tele, Les Paul, whatever you feel like!) and then insert the Amp Simulator MFX on that Part. You then go into the sim and, while the style plays (this is a good time to use the chord sequencer so you aren’t stuck listening to the same chord over and over!) you can play around with changing the amp type (maybe a big Marshall stack, or maybe a Fender Twin Reverb, or perhaps a Soldano amp, experiment!) and then the amount of distortion, the overdrive, the EQ shapes, etc. etc..

What you end up with is usually FAR more realistic that the awful sampled distorted guitars. After all, that’s EXACTLY what guitarists do. Start with a clean guitar, put it through an amp!

The MFX are an incredibly useful way to make a sound, a style, a sequence totally YOURS. Don’t settle for sounding like everybody else! The BK-9 sounds damn good out of the box. But you CAN make it sound a whole lot better by getting creative with the MFX…