I am of course a creator of chord packs however I will spend $10 – $20 here and there for mainly drum samples loops etc. However I have seen sample packs for $1,000 and upwards. I tell you no lie I once saw some sample pack here in Japan for over $8,000, I didn’t check out the full details however I know that is definitely a lot of money to spend on packs. If you have the cash then fair enough but personally if a sample pack is getting close to the $1,000 mark then I would rather buy a piece of hardware. For example a good synthesizer for even less than $1,000 would be packed with high quality sounds and samples. Pay a little more and you would get a better key-bed and weighted or hammer action keys but that would only be important if you were actually a keyboardist.
Brass instrument samples are always are tricky one. Playing samples that are mapped through the keys (MIDI) may not sound authentic or natural enough. High quality recorded loops will sound professional but you are still limited to fixed melodies composed by the creators.
It may be a good idea to either hire or get a friend to play a piece for you as a digital recording to use in your productions. I was in the studio the other jamming the guitarist who was a friend of a friends played some awesome licks. I could just pay for his travel, lunch, studio time and record his guitar licks and solos.
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