This is a bit of a technical one. I've done quite a bit of home recording, but have never actually done any sort of course on how to do it.

I've gradually been getting more ambitious and including more instruments such as hurdy gurdy, highland pipes and accordion. It tends to end up a bit of a mush with all the instruments and I've been told that you can separate the instruments by a technique called "frequency slotting", which means giving the instrument a boost on the EQ in the centre of its frequency range. For instance, acoustic guitar, apparently centres at around 800Khz.

Is there a source anywhere which gives these frequencies for folk instruments.I've tried online and can only find stuff which is very complex or charts for orchestral instruments.