Active vs Passive preamps…or 2 Buffers and a Preamp. – by Henry G.
A year or so ago someone created a poll on this subject. I voted for Passive.

I should point out that my passive system is excessively passive. After my dac chip to the power amp, I have no active components. The most unusual item is the passive output stage of the dac. That paired with a passive tvc (Promitheus audio) gives a real clarity but a thiness to the sound. It seems that the power supply for the dac has a hard task to drive the tvc and 2 I/Cs. I had noticed that trialling active dacs had more low-mid but the tops were always sibilant or rolled off.

I have always felt that clarity, in particular sibilance, was an important thing. It is one of the obvious cues that indicates “no live performance here” just a bunch of electronics. As clean as the sound is, my system has always lacked power and sounded somewhat thin.

Recently pursuing some info re a stepped attenuator, again for clarity-sake, Zaphod pointed out that my passive front-end has terrible impedance characteristics. So taking his advice, I borrowed a couple of buffers. A valve buffer which had no highs and a loose bottom, definitely could use some better valves. The Burson buffer which had much more treble, slightly less bass but some sibilance up top, was a mile better than the valve buffer and “bang for the buck” award, a good improvement for my passive system.

Then Zaphod offered me an active preamp (does active equal a passive pre + buffer?) – a “refreshed” ME24, which I was hoping might work well with my ME550 amp.

Well the ME pre was just great, cleaner tops and better everywhere, not surprising, being about 4x the cost of the Burson. Final check, comparing the ME24 to my passive setup found that the passive has a tiny bit less sibilance up top but this small gain is so insignif, compared to the power and authorithy throughout the rest of the range. The bass has never been as good and the dynamics (“separation” “blackness”, etc) are vastly improved.

Previously, after listening to my system, A9X said he was still not a fan of ESLs.
(Poor man- no wonder he is off wandering).
Likewise, Orpheus who has ESLs, was critical of my amp, (how close he was). Well now I can say that the problem was in fact the extremely passive inputs, not the power amp and not the ESLs. I have a new, improved hi-fi with the ME24. The only bad thing is I have to return it on the weekend.

So although this looks like a victory to the Active camp, I should point out that the wonderful system I have now, only has 1 active stage, the preamp.

IMO – each active stage comes with a cost in terms of distortions, so if you have a cd player and an active preamp, then you may (or may not) get better clarity by using a passive preamp. For the very few who have cdp -> buffer -> active preamp, then you must surely ditch the buffer and get a better preamp or cdp (what ever caused you to get the buffer). 3 active stages is too much.

I get the impression listening to others, that interconnects play a bigger part than I gave them credit. If they are long, then perhaps 2 active stages are required. If they are short then the old “cdp into a couple of resistors(volume control) into the power amp”, (no preamp) may be a great solution.

I have tried to cover a couple of things, hope I haven’t made it hard to follow.