Hi - I'd like to find out your thoughts and opinions on optimal external speaker placement for a DP - in my case, a Yamaha P155.

I've got two external speakers (60W sound system) attached to my P155. Each speaker cabinet is approx. 14"(h) x 7"(w) x 9" (d), and each contain two stacked speakers (3.25" and 5.25"). The amp I am using has all sorts of surround sound options and an equalizer, but I've left all of that stuff off (flat equalizer) with the assumption that I'd start with the sound coming out of the P155 as it is.

I currently have the speakers on 27" tall speaker stands, on each side of the P155, about a foot away on each side. The front of the speakers generally align with the back of the P155.

The odd thing is that it seems I get the "best" sound when I point the speakers towards one another (or even a tiny bit towards the wall behind them), such that the sound is crossing back and forth just behind the P155. "Best" is of course highly subjective. If I point them directly forward, or a bit more towards me, it seems a little harsh, but perhaps I'm doing something else wrong. I was also wondering if the should be sitting behind the P155 pointing straight up, or in some other position.

I know this really falls into the category of "fiddling around with unimportant stuff", but it's also kinda fun too. I thought I'd ask what others thought would be the optimal position of these speakers, if I should continue to use the onboard speakers too, equalizer settings, etc.. (If I turn off the onboard speakers, I lose a bit of the vibration feedback that results from the onboard speakers vibrating a bit, so I've left them on.)

Thoughts? Again, I know this is close to nonsense. I can always use a good set of headphones. :-)

Thanks!

I think it depends on the acoustics of the room. When my speakers were on stands, I had them pointing about 20 degrees away from the front, as I found that pointing straight didn't sound right, pointing towards the player was too blarring, pointing up was too anemic. Now I have them here in my homemade case: http://imgur.com/K9xzx.jpg
Inside the case they are pointed almost straight upward, and outward a little bit. The wing at the top of the case open at about a 45 degree angle provides optimum dispersion of the sound in the room and envelopes the player too... having the wing open once again was too anemic, and having it fully closed gave too much reverb. So it seems for me pointing upward and having an angled surface for the soundwaves to bounce off of is the ideal solution.

I play my Kawai ES6 through a Motion Sound KP-500SN Stereo Keyboard Combo Amp which sits on the floor behind me. It sounds full range and natural. I use no eq.

As mentioned it depends primarily on the acoustics of the room and your placement of the piano. If you think about traditional music halls the space is oblong with the piano at the end with the shorter dimension. If your piano is along the longer wall the sound will disperse and you lose a lot of the secondary harmonics, which might explain the better sound you experienced by aiming the speakers inward and having their wave patterns overlap. Speaker distance from the wall can also impact the lower registers significantly and is worth experimenting with as well.

Thanks for the helpful replies!

Directly behind my P155 is a wall that is essentially a white cedar tongue-and-groove internal wall - there is no drywall or insulation behind it, and it simply separates a room from a storage room. I wonder sometimes if it might tend to resonate a bit, but I think its too thick.

Elhornsun: if you could elaborate a bit on your statement about speaker distance from the wall it would be helpful. Are you saying that the lower registers might be reduced the closer the speakers are to the wall, or the farther away?

Thanks again...

Your ear hear the sound direct from the speaker cone as well as the reflected sound. If the path length from speaker to wall to your ear is exact 1/2 wave length different from the path from your ear directly to the speaker then the two sounds are 180 degrees out of phase and cancel.

But every frequency has a different wavelenght so the cancelstion effect is always frequency dependent

One way that works for this case is to set it up so that ALL of the sound is reflected. However this has the effect if "muffling" the highes.

Notice on most DPs the speaks aim straight up? this is a good compromise because you get some direct sound and some reflected off the fron walls back walls and ceiling. Also I think this is most like a real acoustic piano

try placing the speakers facing up with the speaker grill about as high as keyboard. If yu have a nice hardwood floor you might even try speaker grills facing down.

Keep in mind tere is the concept of "late" and "early" reflections. Early means the sound did not travel far from the speaker before being reflected. You may want to try and eliminate early reflections although some can be used to re-enforce the bass (just get the waves to add in-phase)

Has anyone tried using self-equalizing surround sound systems to account for the effects of room acoustics?

... just a quick Thank You to everyone who responded.

See this from SAE Institute
http://www.saecollege.de/reference_material/audio/pages/Speakers.htm

Speakers are flush mounting, but you can use the recommended angles for the near field monitors.