You do not have to get a new oneAlso Apple have refurbished ones from the Apple store. Most people do more on their tablet than they thought they ever would because of the diverse range of apps available.
It can be a little small for notation, it depends on the staff size and complexity. Many orchestral players are using them now. You do not need the (white margins) on each side of a printed page, and you crop so the music is at maximum size (depending on the aspect ratio of the tablet.) (And using notation software you can specify margin size.) Setting up a PDF app with all your music sheets can take a while (cropping, titling, keywords, categories, composer, key, band or whatever) but once done is very convenient, especially for searching, organising, set lists, rehearsal, practice sessions.
If you have a friend with an iPad, get them to take a photo of some printed notation for you with cropped margins and test with your instrument.
True, as I said, I think Acer (android) have some (had some) available and I have seen a few cheaper models also. Some newer android tablets are coming out in 12 inch sizes although I have not checked to see if a ‘normal’ printed page (with cropped out margins) displays any bigger than on a 4:3 device at 10 inches (although theoretically you could work it out, mathematically at least). There have been rumours Apple might release a bigger tablet size than the current iPad range. If this happens, I am sure many musicians will purchase this, because you are right, although 10 inch works well having notation a little larger would be better. Again it can depend on the distance of the device and if you can move it closer (depending on your instrument) to compensate. There are android devices up to 21 inches size now (HP Slate 21 for instance).
If a music PDF reader app does not work (or install) on a small device, you might be able to use a general PDF reader with your music notation then mirror to a larger screen. I have not tested this to check if there is a resolution problem—it might depend on that specific device.
Many people just use the headphone out for recording, connecting to amps, sound systems etc. but as you know, digital has better clarity.
We have recently been testing iReal Pro with a few interfaces connecting directly to iOS devices providing digital out with the lightning (or 30-pin on older models) connector.
A couple of links:
http://www.apogeedigital.com
http://global.focusrite.com
Generally they are used for recording to iOS devices but there might be some offering S/PDIF output etc.
For android, digital out would involve research to get it working for a specific device, possibly using a USB or HDMI interface for audio output. We have not tested this with iReal Pro.
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