Hi! At a long distance what I’m planning is to fit the RD-700NX inside a grand piano cabinet, including amplification and speakers.
By now I succeeded in making what I consider a very good selection concerning the amp and the speakers: Behringer A500 and B&W 603-S3.
I’ve been using the RD-700NX with a very good PA and tested some other PAs from different renamed brands, but all of them have in common the cooling fan that I don’t like for my purposes.
Beyond that, PAs are very satisfactory if one is playing in a band context or in a noisy environment and they offer great connectivity and control (a mixer with lots of inputs for microphones, CD players, guitars, and lots of control knobs for balance, etc.).
Since my aim is to play at home, as close as possible as I was playing an acoustic baby grand piano, I need a sufficient sound volume with very good quality, without any noise.
I tried my of old Hi-Fi speakers B&W 603-S3 with the different PAs and get disappointed with the sound quality I get: apart some improvement in the response against the PA speakers I noticed the presence of a hum or blowing specially accentuated when playing the keys and during the notes decay time. Also the piano bass notes sound a little bit like produced by an acoustic double bass without the percussion effect present in an acoustic piano.
Of course I also tried keyboard amplifiers, but hey are terrible bad for my aim, since they sound like boxes.
I couldn’t try any monitors, but I realize that many people confirm that active near field monitors are the best choice concerning sound quality – anyway I fear that they don’t spread the sound as an acoustic baby grand piano does.
Finally I decided to buy and test the Behringer A500 – well I know that the web is fool of alerts against Behringer, saying the worst about their products. Sometimes curiosity kills the cat, but I was looking for something with enough power and without a cooling fan and get curious about the A500.
I have some other equipments from Behringer and since they are not expensive and I’m still happy with them, I decided to run the risk and bought the A500.
Surprise! It sounds beautiful with my RD-700NX, with my old B&W speakers and an old mixer I have and is good to boost a little bit the output level from the RD-700NX – this seems to be a characteristic at least with the different Roland digital pianos I tested: all of them offer a very low output level as regards the acoustic piano sounds (and an annoying unbalance between the acoustic piano sounds and all the other sounds, EPs, organs, etc.. We have to be careful when moving in a performance from acoustic pianos to other instruments!).
Well, about the sound quality I have now with the A500 and the B&W: a very clear and pure sound, let’s say "What I Hear with headphones Is What I Get" from the A500 and the B&W … WIHIWIG! No noise at any frequency and the low frequency notes sound really like hammers knocking the strings in an acoustic grand piano without any boom or artificiality.
About the A500: So far so good. I admit that the components inside may be not so durable as in an expensive amplifier. I will use the A500 very pleasantly while it lasts!
About the B&W speakers: I was afraid that they might not respond so well with an amplifier like this, but fortunately I believe that I will not need other speakers. Anyway one of these days I will also try with my Focal-JMlab Chorus 726 S.
About the RD-700NX acoustic piano sounds: Now I’m happy!
My recommendation: test various solutions and let your ears choose the best one!