Do I really need a preamp?


As I continue to upgrade my system, I keep asking myself this. I'm looking at the Benchmark DAC2. Since it acts as a preamp, do I really need one? Currently I'm using Peachtree 220 with the NovaPre and it sounds nice, but like the way these things go, I think it could sound even better. With the upgrade, I'm thinking I can eliminate the Pre and run the DAC2 with a new amp (thinking D-Sonic maybe)but I'm not sure.

Any useful information would be appreciated. Pretty new to all this, but deeply obsessed.
robcentola
Marqmike, I have always seen it as a statement of how bad many active line stages must be for a passive to beat them. I can't use a passive in my system- the result would sound broken- no bass, no impact. The active preamp I use has more detail as well.

So much depends on setup! My interconnect cables are fairly long, something that is not a good idea with a passive. I find though that by keeping the amps by the speakers and the speaker cables short that I get a lot more resolution. The front end equipment- preamp, tt and digital, reside on an equipment stand that is located in a room nadir where there is the least bass. It is also not too far from my listening chair.
Its all about synergy as usual I think. Passives make sense to me if properly mated to suitable sources electronically. That might even be one of the best ways to go if done right, at least from the "purist" point of view, a simple signal path that mates well to gear upstream.

What's not to like?

Mating of active pre-amps, especially tube gear, opens up a similar but different can of electronic mating issues to address. Plus the preamp itself becomes more of a potential sound tweak.

There are so many ways to tweak and do it right. Active/passive, who cares really? Just choose your paradigm and do it right! Passive pre-amps offer a different way to do things. Options are good. Just get it right.
The problem you are usually facing with passive controls is the interconnect cable. An active line stage will usually be less sensitive to the cable. In fact if done right, the active line section will control the cable so well that it will have no sonic effect at all.

Passives OTOH require that one be very careful about the cable. Some passives are lower values, such as 10K, which make them less cable sensitive but then you have the problem that not all sources can drive the 10K properly.

I have presented some of the math about why passives can put you at a disadvantage elsewhere on this site, and the math shows that the quality of the control has nothing to do with it.

This is not to say you can't get a passive to work quite well, just that you do have to be careful and results vary quite a lot. Generally speaking though, it means short cable runs.

'Just get it right' is indeed excellent advice.

Mapman is right with proper mating with passives.

And as I have stated many times.

If you decide to give a 10kohm passive a try, such as the very affordable $49.00 Schitt SYS passive pre. http://schiit.com/products/sys-passive-preamp,
the only proviso to look for to give them a great match are.

1: Interconnect to power amp to be low capacitance (<100pf per foot) which most good quality one are, and 3mts or less long.

2: Tube output sources can be a problem if higher than 1kohm output impedance, solid state sources are normally never a problem.

3: Input impedance of the power amp should be 33kohm or higher, which most are (47kohm being the standard).

If you have these, which 99% of systems are, then you can reap the benefits of the transparency and dynamics that a passive will bring to your system.

Cheers George
George is mostly correct here, just watch out that some solid state amps have a 10K input. 47K is not a standard.