Who needs a Preamp??

The reason an active line section can sound better than a passive has a lot to do with interconnect cables. Passive controls have poor output impedance- usually quite high, which allows the interconnect cable to do its worst mathematically speaking- and this is audible as others on this thread have already pointed out.


If the line section has a low output impedance it can swamp the characteristics of the cable- in other words its output impedance dominates that math I mentioned. So less effect. If you've ever had to audition interconnect cables to pick the one that sounded right then you know exactly what I'm talking about.


Now this problem was identified and dealt with by the recording industry decades ago and resulted in what we know as the balanced line standard (AES48). If you equipment conforms to this standard you'll find very little difference between cables. Most high end audio products do not, but if you have one that does, interceding it between your sources and amps can easily increase transparency if you keep the connections to your sources short. 

Now of course such a line section could be built into a DAC- but then you have the issue of if you ever want to improve the DAC or the line section, you have to replace both (and its often not a good idea to have a DAC and line section run off of the same power supply). DACs are notorious for going out of date; this is a very real issue.

Seriously, if you’ve already set your reference point so low, you are probably seeing the expense of adding a decent preamp, power cord etc. a waste of money, right?

The VC in players or DAC are purpose built. IMHO, they can never equal or replace the SQ upgrade comes from a high quality preamp not to mention the increased functionality.

Buy a cheap pre and it will degrade or yield no improvement in the SQ vs going direct. Buy a high quality preamp and you will never go back to serviceable VC in OPPO or PS Audio.

Direct without preamp is better, except when it isn't.  :) 

douglas_schroeder2,015 posts10-28-2019 11:02amDirect without preamp is better, except when it isn't.  :)

Hey, I was about to say that, no fair !!!

Doug said it best. I will say The Truth preamp has been a revelation to me over the last three weeks. It is a zero gain, active input preamp that for the first time in my audio experience, sounds better in many ways, to many big dollar active tube and SS preamps I have owned. It has an output impedance of some 3 ohms and an input impedance in the stratosphere! No caps or resistors or volume control in the signal path.

It seems to deliver all the sonic benefits of a great passive without most of limitations of system synergy. The dynamics are there and is doesn’t suffer from the thinner sound I find with many passives.