RD-9 Review
Build Quality
The country of manufacture is China on my unit. The RD-9 has a metal bottom base, and the rest of the sides are plastic. Although there is a lot of plastic used in the housing, the RD-9 feels solid.
The RD-9 is made to look like a TR-909, and the row of 16 lit step keys appears to be mechanical in photos. However, the RD-9 does not use mechanical switches, or any type of computer keyboard-quality switch. The RD-9 step keys feel and operate like all the other membrane keys on the unit. The covers for the step keys are plastic, and the mechanism underneath those covers feels just like the other membrane keys on the unit.
The "imitation" computer step keys are so far away from any type of real computer keyboard, that if you gave an office worker a keyboard with only RD-9 keys to type with, they would quit their job within a couple hours.
In direct sunlight, it can be hard to see which step keys are lit, and the farther the viewing angle is, the harder it is to see the LED lights.
The keys on the RD-9 feel stiff and wobbly, kind of like the membrane keys you might find on a cheap outdoor electronic keypad. When you press them and they snap down, the membrane sometimes doesn't collapse evenly, especially on the bigger keys. I find it easier to use 2 fingers on the bigger or wider keys. However, the keys still work electrically like they should.
It would have been nice to have been given actual mechanical keyboard switches, or at minimum, actual membrane computer keyboard switches for the step keys, or buttons that don't require you to press down so hard. The rest of the membrane keys could have been less stiff, more like the keys you would find on a calculator, would have been nice. Even 12 USD calculators have far better keys, so why didn't they just use keys from a cheap calculator?
Other than the keys being "just barely good enough to not want to return the unit", the build quality looks good for the price.
User Interface
The RD-9 is supposed to be a better, more enhanced TR-909. While I don't like the RD-9 keys that much, the layout of the interface is well thought out for live performances. This is a very playable instrument. The RD-9 features many things the real 909 does not offer, like mute and solo buttons, and built in effects. The best part about the RD-9 is that it is brand new, and you don't have to deal with the maintenance problems of a drum machine built in the 1980s.
If you see people twisting the level knobs really quickly on TR-909s during performances, don't expect to do this on a RD-9, as the RD-9's knobs have high turning resistance.
To switch patterns while playing, you'll have to smack the stiff keys, basically. You'll have to kind of think of the keys as MPC drumpads, and use similar force.
The RD-9 sequencer is limited to only 4 measures. While that is more than the real 909, a maximum measure limit of 16 measures would have been better. The autofill cannot be set to automatically add a fill every 4, 8, or 16 measures.
Sound
When you first hear the RD-9, it becomes obvious why the TR-909 wasn't commercially successful. A 909 does not sound like a real drummer. However, the 909 was the drum machine that was used on countless tracks, and people want a RD-9, because they want something that sounds like an authentic TR-909, without paying the collector price.
I don't own a real 909 to compare between the two, but the RD-9 sounds close enough to a real TR-909 to me, in comparison videos. In a mix, I don't think anyone would tell the difference. Also, real 909s don't sound exactly the same between each other.
The sound of the RD-9 is good, dynamic, and punchy. Be careful with headphone volumes, as the RD-9 has more punch than a sampler playing a sample of a 909.The effects give extra flexibility to the sound.
When it comes to sound, no complaints. Just be careful with your ears.
Conclusion
A TR-09 is another option from Roland, but it doesn't have individual outputs for each voice, does not use analog circuits, and the user interface is tiny like a toy for kids.
A real TR-909 costs thousands of USD, while replicas from Dinsync and Steda cost about 1000 USD, for a kit you have to assemble yourself. With a Dinsync or Steda replica, you get the nice mechanical switches and an "authentic" 909 experience. The catch is you are given a bare board with hundreds of tiny electronic parts that you have to solder in yourself. If you make one mistake, your replica may not work right or at all, and you have to find where you went wrong. If this sounds like a fun time to you, or you solder PCBs for a living, why not get a replica, if you have the money and time?
For the rest of us, a RD-9 is currently the only real hardware analog-digital option to get a new pre-assembled 909-sounding drum machine for under $1000 USD. And it comes with more features than a real 909, and it's interface wasn't made for kid's hands like a TR-09.
Only one question remains for me: who at Behringer, was responsible for those frustrating RD-9 buttons?
PROS
Good sound for the price
Mute and solo keys
Features extras not found on TR-909s
Housing feels very solid
Layout made for live playing
CONS
One of the worst buttons you'll ever see on any electronic device
Stiff knobs
No true autofill
No built-in reverb/distortion
Some may prefer the original 909 sequencer