The bridge is quite a stiff piece of wood (it's not spruce as is the soundboard) so that string vibration would be transferred almost instantly to the soundboard (2 ms maybe?).  From my structural engineering background, I would suspect that the bridge is much stiffer than the soundboard which means that the bridge would transmit its vibrations along at least 24 inches (610 mm) of  the bridge.

This is close to 1/2 the width of the 52 inches wide (1.32 m) soundboard - which would dilute any positioning of the sound from left to right.

My personal bias is that a strong observance of the bass coming from my left side is mostly a preconceived perception based on where the strings are, but I would gladly bow to any comments from the Pianoteq gurus (Edit - actually Guillaume has already commented on this).

The following video is interesting - starting a bit into the video it says "Note 70" which is fairly high up in the treble.  Even when the piano shape is changed radically, this high note always starts at the far/small end of the soundboard, and doesn't seem to propagate to the right side where it should if the high pitch sounds come from the right side.

http://www.youtube.com/watch?v=GL5f-EcqPOc

Glenn

Interesting indeed.
I suppose I could be interested in simulations that pan treble notes from right to left "appropriately" and bass notes from left to right, at least at some intellectual level.
First I would want to find a way to mount speakers horizontally and keep them "free" to radiate downwards from their backs as well as up towards - Ahh, I would need a "lid".
This room isn't big enough.

I do wonder what one could REASONABLY do with a very large speaker baffle to emulate a piano sound board and many small drivers strategically placed to excite it.
With many channels driving each small driver differently.

OK, back to reality - I need to PRACTICE !

This is close to 1/2 the width of the 52 inches wide (1.32 m) soundboard - which would dilute any positioning of the sound from left to right.

My personal bias is that a strong observance of the bass coming from my left side is mostly a preconceived perception based on where the strings are, but I would gladly bow to any comments from the Pianoteq gurus (Edit - actually Guillaume has already commented on this).

The following video is interesting - starting a bit into the video it says "Note 70" which is fairly high up in the treble.  Even when the piano shape is changed radically, this high note always starts at the far/small end of the soundboard, and doesn't seem to propagate to the right side where it should if the high pitch sounds come from the right side.

http://www.youtube.com/watch?v=GL5f-EcqPOc

Glenn

2.  Can anyone actually say the bass sounds definitely come from the left side of the piano as you are playing it?  Or is this an impression based on what we think it should sound like?  Keep in mind that the level of sound that comes directly from the strings is negligible so the position of the strings isn't very significant (if this is doubted, think of the sound that comes from a solid body guitar when the power is off).Glenn

But you initially said "as you are playing it," which means while sitting at the piano...

I would have to say that, even backed off from the piano some, I do notice that the left hand strikes come from the left, particularly on low strikes, and particularly because I can hear the sound of the hammer striking the strings on the left and to a lesser, but still noticeable degree, the vibrating strings. As the force increases, the sound spreads more rapidly to the entire soundboard, but the amplitude of the hammer strike and the vibrating strings also grow louder. My impression is that the sympathetic vibrations of nearby strings also increases the sense of where the sound comes from.

What I don't quite understand, though--for how long is the amplitude of the sound on the soundboard localized near where the string is coupled to the soundboard with the bridge? Of course the vibrations spread rapidly and the various modes on the soundboard vibrate at the various pitches, but isn't there at least a brief time--before the vibrations reach the outer edges of the soundboard and start back inwards--when the amplitude of the soundboard near the string is substantially greater than the amplitude anywhere else on the soundboard? (Just as the amplitude of the initial sound of the string is at first greater, before the several strings for the note start to go in and out of phase?) It may last only a very few milliseconds, but the ear can register a very few milliseconds.

Or does the bridge spread the vibrations along the length of the soundboard, so that the emphasis near the string is reduced? (Depends on the way the bridge is made and coupled to the soundboard?)

Hem... (embarrassed) ... You are perfectly right about the bass sound, one cannot tell that it comes from the left side as the whole soundboard is vibrating and exciting the air. The sound cannot be considered as a point source, because the surface of the soundboard is large compared to the wavelength (for example 10 centimeters at 3400 Hz in the air), thus their occurs complex phenomena, waves additions, cancellations, etc. This is a key point in the piano sound. The sound source is a true surface source, and that's precisely what we tried to model in Pianoteq 3.

After I made this post, I went to see my friend the piano restorer, and we did a crude test to check the stereo separation while sitting at the piano.  One of us would alternately strike a low bass note and a high treble note, while the other would move around poking his head under the lid to try to determine where the sound seemed to be coming from.

His ears are better than mine (he's 30 years younger) and he concluded that there might be a 10 to 15 percent stereo separation between left/bass and right/treble.  That's for the pianist.

The separation for someone fifteen feet/5 metres away is basically zero.

As for the point source comment, the soundboard is certainly large enough to not be a point source if one is close to the piano, but back up six meters (20 feet) and it's essentially a point source with no frequency separation at all.

As for the complex interaction of sound from the board, I would totally agree - changing the angle of the lid on an acoustic grand changes the sound quite a bit.

Glenn

NeilCraig wrote:

For anyone contemplating i7 for a workstation, remember that it has a triple-channel memory configuration so it can handle 12GB.

It can handle even more than that, it's 64-bit so it can handle up to 16 million gigabytes of RAM. It's all dependant on the motherboard, still. So, if motherboard supports 32 GB of RAM, that's what the CPU will use.

Of course, you're right, the theoretical limits are ridiculous, but motherboards available now have 2x3-slot memory banks and 8GB RAM sticks are hideously expensive and actually aren't truly 8GB, rather 2 x 4GB "pretending" to be 8GB, so currently the practical limit is 12GB.  At least this was true a few months ago.

Best//Neil

1.  If we are trying to imitate an acoustic piano, then we should remember that the piano is essentially a point source of sound that in itself has very little significant reverberation. True, it's larger than a violin, but compared to the size of a concert hall, it's a point source of sound.
2.  Can anyone actually say the bass sounds definitely come from the left side of the piano as you are playing it?  Or is this an impression based on what we think it should sound like?  Keep in mind that the level of sound that comes directly from the strings is negligible so the position of the strings isn't very significant (if this is doubted, think of the sound that comes from a solid body guitar when the power is off).
I'd be interested in hearing from the experts - the people that created Pianoteq know more about it than all of us combined, and certainly a lot more than I do.  Maybe I'm right off the mark.

Hem... (embarrassed) ... You are perfectly right about the bass sound, one cannot tell that it comes from the left side as the whole soundboard is vibrating and exciting the air. The sound cannot be considered as a point source, because the surface of the soundboard is large compared to the wavelength (for example 10 centimeters at 3400 Hz in the air), thus their occurs complex phenomena, waves additions, cancellations, etc. This is a key point in the piano sound. The sound source is a true surface source, and that's precisely what we tried to model in Pianoteq 3.

For anyone contemplating i7 for a workstation, remember that it has a triple-channel memory configuration so it can handle 12GB.

It can handle even more than that, it's 64-bit so it can handle up to 16 million gigabytes of RAM. It's all dependant on the motherboard, still. So, if motherboard supports 32 GB of RAM, that's what the CPU will use.

You want to buy now, somewhat cheap and updating is not important, Q6600

I would agree.  I built a Q6600/8GB Server 2008_64-workstation system for my brother to run East/West QL Pianos on and whilst even with a Velociraptor it won't cope with this (!) for PTQ purposes it is ridiculously over-specified.  In fact if QLP hadn't been so unusable I'd not have discovered PTQ.

Having said that, my own machine is a 3-year old Pentium-M 1.86GHz and it handles the Rach Prelude in C# minor with aplomb.

For anyone contemplating i7 for a workstation, remember that it has a triple-channel memory configuration so it can handle 12GB.

Best//Neil

I think you're right with your assertion that 5.0/1 audio isn't going to give an accurate representation of an acoustic grand.  Even trying to recreate a piano in an acoustic through a 5.1 system in a room is problematic and I would say that sitting at a keyboard in the middle of such a room would be very disconcerting. 

I think the results would be far more realistic using 5 or more speakers of *mono* sound spaced around the "soundboard".  Whilst this won't be perfect, as a loudspeaker is extremely very directional at frequencies with wavelength < diameter of the cone, if the speakers pointed upwards at, say, a lid, the sound should be pretty diffuse.

Best//Neil

My ramblings on this:

1.  If we are trying to imitate an acoustic piano, then we should remember that the piano is essentially a point source of sound that in itself has very little significant reverberation.  True, it's larger than a violin, but compared to the size of a concert hall, it's a point source of sound.

2.  Can anyone actually say the bass sounds definitely come from the left side of the piano as you are playing it?  Or is this an impression based on what we think it should sound like?  Keep in mind that the level of sound that comes directly from the strings is negligible so the position of the strings isn't very significant (if this is doubted, think of the sound that comes from a solid body guitar when the power is off).

I suppose the relevance of this discourse to the OT is that a 5.0 or 5.1 system would be very expensive, and wouldn't come very close to a real grand piano sound.

I'd be interested in hearing from the experts - the people that created Pianoteq know more about it than all of us combined, and certainly a lot more than I do.  Maybe I'm right off the mark.

Glenn

1) Get a cheap AMD motherboard + CPU combo from somewhere like Fry's. I picked up a motherboard with a Dual Core 3.1 GHz (second fastest for the dual cores). By now, the quad cores are a lot cheaper so its up to you. You could always buy a dual core and drop in a quad core on an AMD motherboard until its cheaper and programs start using it as standard. Since you said cheap I mentioned AMD. Better dollar to speed ratio.

2) All CPUs sold currently are 64 bit. Its worth it to have a 64 bit operating system but don't remove your 32 bit OS yet. You can find out if everything you need right now is supported by the 64 bit OS and if it fits your needs. 64 bit allows you to have more than 4 gigs of ram.

3) Answered already, each core will run at 2 ghz.

4) The e5200 is OK, but I don't know if you're going to be able to drop in the newer and more powerful CPUs that are coming out.

5) Core-2 is the designation given to the line of Intel's newer CPUs like Core-2 Duo, Core-2 Quad.  The newest line, the Core i7s are something worthy of consideration if you want to upgrade.

Take a look of in this video. This guy made a adaptartion of his triton digital piano to his old real upright piano:

http://www.youtube.com/watch?v=0N4XacwfD5Y

Now that pianoteq have 5.1 sound, and ability to control the sound in each channel, by mic position, let's supose someone it's trying to place a 5.1 speaker system inside the Grand piano wood body.

That would be a challenge, to find the optimum adjustment and speakers placement to get very colse to the real thing.