I have certainly done my share of mods and totally agree with Undertow.
First, if you're going to do any mods it is only going to be cost effective in the long run if you do them yourself. You can usually get back the extra price of parts but can never recoup the cost of labor for this, and that is where you will spend a lot of money.
Second, doing this yourself is a learning experience. You will find out over time what works and what doesn't, what is worth the cost and what isn't.
Third, modding something expensive is a lose-lose situation. Nobody will buy it in the aftermarket and the improvement will likely only be a matter of minor flavoring. Modding something cheap is fun, you don't have to put up much cash and the improvement in sound can be dramatic.
Fourth, digital is constantly changing, so units that are 5 years old and sold for a lot of money can be matched by far less expensive units today. The place to look for upgrades are the power supply (which is always a good place to start) and the analogue output stage. Without completely redesigning either you are looking at caps, diodes, connectors and op-amps probably. Power supply conditioning/filtering also seems to improve digital performance moreso than in other places.
All in all, if you're going to do it, do it yourself and have fun taking this hobby to the next level of understanding and enjoyment.
First, if you're going to do any mods it is only going to be cost effective in the long run if you do them yourself. You can usually get back the extra price of parts but can never recoup the cost of labor for this, and that is where you will spend a lot of money.
Second, doing this yourself is a learning experience. You will find out over time what works and what doesn't, what is worth the cost and what isn't.
Third, modding something expensive is a lose-lose situation. Nobody will buy it in the aftermarket and the improvement will likely only be a matter of minor flavoring. Modding something cheap is fun, you don't have to put up much cash and the improvement in sound can be dramatic.
Fourth, digital is constantly changing, so units that are 5 years old and sold for a lot of money can be matched by far less expensive units today. The place to look for upgrades are the power supply (which is always a good place to start) and the analogue output stage. Without completely redesigning either you are looking at caps, diodes, connectors and op-amps probably. Power supply conditioning/filtering also seems to improve digital performance moreso than in other places.
All in all, if you're going to do it, do it yourself and have fun taking this hobby to the next level of understanding and enjoyment.