Yesterday I picked up a near mint condition Yamaha FX900 Simultaneous Effects Processor for my second Yamaha DX-7 mki. I had already been using a Yamaha FX500 (little brother) with my first Yamaha DX-7 and thought the FX900 would work nicely. I was lucky to find one for sale at the used music shop I frequent. The Yamaha FX series works great with the Yamaha DX-7 because they were released during the time Yamaha was pushing the envelope with new digital technology in effects processing. Many effects processors today are emulating analog or amplifier sounds and while that is cutting edge of today, I wanted something around the time the Yamaha DX-7 was flourishing. The FX900 comes with 100 pre-set programs, 100 user-memory locations, and is based on 11 algorithms ‘built’ from four algorithm blocks. It’s a very warm but digital sounding effects processor that works wonderful with the Yamaha DX-7. It’s amazing how much the DX-7 comes to life with a decent set of effects.
While the FX900 is an excellent solution for Yamaha DX-7 effect processors it does have a couple of drawbacks. The first I found is that it doesn’t have a phaser effect. One could likely create one with the existing modulation effects but there isn’t a plain and simple dedicated phaser effect. Second, many of the presets use distortion so you’ll need to edit those to make them better for keyboards. Many don’t find the distortion to be all that great, but for the Yamaha DX-7 I actually think they are quite good especially if you custom program them to your liking. Guitar players are particularly strict about what they like with distortion and most people who review the FX900 are guitar players so keep that in mind. With regards to keyboards, particularly the Yamaha DX-7, the FX900 works extremely well with all effects on board. The Yamaha FX900 was a very expensive professional effect solution back in the day so it definitely delivers quality pro effects.
A few other vintage alternative effect processors that I feel that would work great with the Yamaha DX-7 are the Yamaha SPX90, SPX50D, Boss SE-70, and the Korg A1. I used to have a Boss SE-50 and while it was very good with the Yamaha DX-7, I didn’t particularly like the interface much. I’ve heard the SE-70 is a bit better. I haven’t seen a Yamaha SPX90 around here in my neck of the woods in Nagano, but there is a brand new looking Yamaha SPX50D sitting in a used shop down the street. I may pick that up as I’ve heard it’s very similar to the SPX90. It may be fun to try that with the Yamaha DX-7 and see how it fairs. I also have a Korg A1 which I like with the Yamaha DX-7 but I also use that for a lot of other instruments so it’s pretty well tied up at the moment.
Right now I am perfectly happy with the Yamaha FX900 and it’s probably the best multi effects processor I’ve used with the Yamaha DX-7mki thus far. The sound is just amazing, especially in stereo. Note I run the Yamaha DX-7 mono out to a single input of the Yamaha FX900. I then run stereo out from the FX900 to two inputs on my Yamaha Mixer. I then pan the two channels to get a stereo sound and wow! it’s fantastic.
If you are looking for a good digital effects processor produced around the time of the Yamaha DX-7, the Yamaha FX900 would be one of many great choices. The smaller FX500 would also work very well. Without effects, the Yamaha DX-7 can sound really dry. If you haven’t heard a Yamaha DX-7 through a decent effects processor you need to fast! It’s wonderful and definitely lifts the level of the DX-7 to a much more usable status in today’s music. I now feel the Yamaha DX-7 is back in business with the big boys! Have fun!