Are Pre-Amps necessary?


With all the advances in digital sources, do we still need a $5,000 pre-amp?

All we need is a switching device and maybe a Phono preamp/RIAA curve device.

Tone controls are another thing of the past. Room correction has taken over if that is something you want to use.

Thoughts?
vanson1
Just looked overa  few DAC's, that I like, None have vol pot.
I have to cancel my above opinion,. Linestage are necessary as now you get more opportunities to pick which CD player/DAC you want.
So yes linestage are valid and necessary.
Thanks for all the great discussion.

The collective knowledge of this forum is fantastic. 
I tried my Bricasti M3 direct in place of a Lamm L1. The noise dropped and my perception of resolution increased. The first minute I thought the change was for the better. Percussive instruments were sharply augmented over vocals (like a bad mix) and the tone was worse. While I already know the Lamm is not the standard in transparency, it sounds better. I have read similar experiences from others. You have to solve for the preamp no matter what. It makes a huge difference.
This thread goes to show you many paths to audio satisfaction. Passives, actives, no pre, resistor based, pots, transformer coupled; seems all have their adherents.

It makes sense no pre would be most transparent, resolving, the straight wire concept. But some prefer flavoring, and bit stripping can be concern.
At one time or another I've tried all the above volume controls, I could see how one would prefer one over another. At present and highly likely long term, I'm keeping my present transformer coupled active pre. Adds flavor I prefer and virtually no loss of transparency, resolution. Also gives me added input for vinyl setup.
It makes sense no pre would be most transparent, resolving, the straight wire concept.
Go back earlier in this thread to see what a straight wire isn't always the most neutral. The problem is that a passive volume control isn't a bit of wire. If it were, it would not have a resistance value.


Math and engineering principles are at play here- when you put a resistance in series with a source impedance which is expected to drive something to the best of its ability, its rarely a good thing. This can cause an audible and measurable loss of bass and impact. Put simply, its an example of a thing that is too simple to to its task properly.


This is not to say that you can't get it to work. To do that you have to be sure that your source has a direct coupled output and is capable of driving the load (the input of the amplifier) properly. And the interconnect cables will have to be kept short, and RCA only (balanced lines can't be executed with a passive volume control and observing the balanced line standard at the same time).