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The really intriguing thing about this is that it is the first iPad app with sample streaming (i.e. the entire sample doesn't have to fit into the iPad's somewhat meager RAM at once). Even though iOS is derived from OS X which supports streaming, no one had come out with an iOS app that did this, so it was not clear that the hardware/software was capable. But here it is! I'm curious about how well it runs on different models. The 3rd and 4th gen iPads have more RAM than any of the others, and the 4th also has a faster processor speed... I wonder whether/how these differences will manifest themselves when running this app (i.e. whether some models have greater polyphony, or run with fewer glitches or increased reliability).
This page http://www.crudebyte.com/mobile/cmp_grand_piano/ lists the polyphony limitations with older devices. If I can get near some wifi to download it in the near future I might give this a try.
Thanks for the link to the polyphony chart. It does seem to vary with how much RAM the units have. There's no spec there for the 4th gen iPad that has a faster processor... I wonder if that might improve latency, for example.
I was curious about how they were able to do a streaming piano, where no previous sample-based apps on the iPad had ever streamed. Based on a post in another forum, it seems that what was required was for Apple to support it at the OS level, it's apparently a recent addition to the functionality provided within the Apple SDK (that is, developers couldn't do it until Apple supported it in the development environment).
This is from the post by Gospel Musicians (Neo Soul Keys), discussing their new EP for iPad:
"we are proud to say that we are one of the first developers to offer Real Sample Streaming using a brand new system in Apple's SDK. It's so new that we had to work with the developers directly.
As a result, we are able to make our sample libraries large with the same sample stream of EXS or even Kontakt. Here are the specs of the new APP:
1. Polyphony is close to 64 and even higher on the iPad 3 or 4 2. Latency right now is 20ms. Not bad, but not super, but remember you loose CPU the lower the latency 3. Velocity layers is 8, instead of 12 with Kontakt
There is a small bug in the first version if you sustain the samples for a long time, say 30 seconds, it will bend out of pitch a little. This is 100% Apple's doing and they hope to fix it in future versions. As we said, this is very, very new and we are one of the only developers working on this. ... in about 6-months we are guessing all of the bugs will be ironed out and remember iPads are getting more powerful as well!"
Better 32 key polyphony and max 5 ms latency, than 64 and 20ms - which makes the instrument unplayable. But with current speed at which tablets get faster, this will be an issue of the past sooner or later. Imagine a nice MIDI controller, simply connect iPad en play away with the software of your liking. A nice touch screen interface as a bonus - no longer need a Kronos or Physis for that - and very small footprint + ultra portability .
Tablets will be more and more common in a setup in the coming future and perhaps will replace laptops altogether in certain situations. For now - it's still in it's childhood. Like early software instruments on the - at that time - too slow computers.
Subsequent to the post above, Gospel Musicians added this interesting info about their streaming iPad EP:
1.23GB samples (328MB Apple Lossless)
("Apple Lossless" being a compression scheme for audio that is not "lossy" the way MP3 is, i.e. it maintains all the quality of the original.)
Since there is only 328 mb of actual data, it sounds to me like the app is not actually "streaming" much, if at all.
Every iPad after the first is capable of loading a 328 mb file into RAM, and I suspect not coincidentally, this app works only on 2nd generation and newer iPads. (The first iPad had only 256 mb RAM; all subsequent iPads have had at least 512.)
So it sounds to me more like it could be a kind of "simulated" streaming. Yes, you are accessing more sample data--1.23 gb worth--than can fit in RAM, but if all that data is resident in RAM within the 328 mb compressed file, then it is not streaming in the sense that we usually talk about it (i.e. accessing the device's storage component in real time, rather than keeping all the audio data in RAM).
I suspect what was really new about this, and what needed Apple's OS support, was the ability to keep an entire 328 mb compressed audio file in RAM and access (while decompressing) its contents randomly and instantaneously, while also being able to access multiple elements of its contents simultaneously.
Background for those who may not follow all of the above:
Normally, the OS keeps only a small portion of a large audio or video file in RAM. If you're simply watching a movie or listening to a long audio file, only a small amount of the data needs to be in RAM, since the OS has plenty of time to background-load the next part before the user needs to see/hear it. Even the very first iPod could do this. It is a kind of streaming, but too slow for real-time instantaneous access to any data within the file, as we would need for a piano application. Not only is this streaming linear rather than random access (the system always knows what bit of info you will nee next, unless you skip to another part of the song/movie), but this streaming only requires accessing one data stream at a time, rather than dozens. (You can think of a typical streaming song or movie as being equivalent to a device with one-note polyphony... it never needs to play so much as two parts of the file simultaneously, much less 64 parts of the file as would be needed for 64 note polyphony.)
For something like a piano, where the data is not being played linearly (start of file to end of file), but rather being accessed randomly as different keys are pressed (and that data must be available instantaneously), and where multiple sets of data need to be played simultaneously, the entire data file would normally have to be in actual RAM. A standard computer with disk-streaming gets around this by pre-loading the attacks of every note into RAM, giving the computer some time to fetch the rest of the needed data to complete the playback of the note. The iPad has not been able to do this, whether for reasons of limitations in the hardware, the OS, or both (though iOS is derived from OS X, which certainly can do it).
So getting back to the apps discussed in this thread, it looked like they had brought streaming to the iPad. But based on the info above, I suspect that the iPad is still not capable of true streaming from its flash storage, and still requires the complete data set to be resident in RAM, even if only in compressed from.
The CMP and Sampletank pianos represent good value for their money. I have them all but they are weak in a few areas including string resonance, dynamics and often basic tone (audible loops, stretching), although they provide some adjustment. So I would say OK at the moment for fun, practise, better portability than PC, laptop, but not yet, despite some claims, studio type quality. Garageband pianos, IMHO, are awful.
The CMP and Sampletank pianos represent good value for their money. I have them all but they are weak in a few areas including string resonance, dynamics and often basic tone (audible loops, stretching), although they provide some adjustment. So I would say OK at the moment for fun, practise, better portability than PC, laptop, but not yet, despite some claims, studio type quality. Garageband pianos, IMHO, are awful.
Garageband organ is pretty nice, though limited in its MIDI functionality. Garageband EP has a nice sound, but polyphony is awful, like 7 or 8 notes.
As for piano quality of any of the iPad options, I don't think anyone is expecting Ivory-type performance out of them, I wouldn't compare them to that. But for gigging (or home use where computer interfacing is impractical or undesirable for some reason), considering the convenient form factor, it would be interesting to compare them to the built-in piano sounds of the various slabs. Maybe dewster can run some tests if he picks up the DPBSD gauntlet again. And someday I'll get my own piano comparison site running... I have a ton of files for it and just haven't put it together! (Not analytical like what dewster does, just lots of pianos playing the same MIDI file for comparison.)
On the iPad 2 there is no way to reliably keep 328mb of audio data in RAM. iOS will terminate the app long before reaching 328mb.
Interesting. And now that I think about it, I can see why that could be. Originally, I was thinking that a 512mb iPad 2 would have to be able to load a file that was 256 mb bigger than what a 256 iPad 1 could load, so 328 seemed very reasonable in that context... but that assumes they are running the same OS. Neo Soul requires OS 6.1 -- and the iPad can't run anything newer than OS 5.1, very possibly because it doesn't have enough memory. So I can easily see where an iPad 2 would behave as you describe. And if that's indeed the case, maybe there is some kind of streaming going on after all, or maybe Neo Soul loads a smaller-than-328 mb version on an older device that doesn't have the 1 gig of RAM that the newer iPads do, or...?
