Is my preamp useless?

Charles1dad,
That "specific" situation that you mention is correct, at least in my experience. Below are the situations when I feel that a passive will not work:

1. The source signal is very low
2. The amplifier sensitivity is more than 1V for full output
3. The speakers are less sensitive (less than 87 db and 4 ohms). Generally the BIG monsters with 10-15" woofers and 4+ drivers will most likely not work with passives.
4. You need more than 2 meters of ICs between source and amp
5. You need more than 15 feet speaker cables

I am sure that speaker wires also will make a huge difference. But I have not looked into that measurements.

On the other hand, if you carefully assemble a system around a passive - it is all bliss!

Slanski62, try the passive! The complaints about lack of drive, thinness or lack of involvement using a passive are completely system dependent. I am currently using a passive (Audio Synthesis) to Manley tube monos via 5m (!) of Nordost, driving 93db efficiency speakers and the results are fantastic. There will be exceptions to every "rule" proposed in the posts above which will depend on the particular components in your system, the particular passive you use, and your own sonic tastes. For instance, in my system, the passive brought significant improvements in the areas of transparency and tonal refinement with no loss of dynamic verve; there was a reduction in tonal fullness compared to my active pre, but the change was a welcomed change since my system was overly full sounding to begin with. You will never know the real answer to your question until you try it.

Re Nelson Pass and the integrity issue: Isn't it obvious that even if a manufacturer believed that a good passive is potentially superior to any active (I believe it can be) in a specific system, that given the fact that an excellent active will work well in many more systems than a passive will with its much more specific requirements, that this is the reason that a manufacturer such as Pass chooses to offer active preamps?

Slanski62, did I say "try it" :-)

+1 Frogman. If the OP is still around, remember that Frogman is a musician who is intimately familiar with what real instruments sound like and is fully committed to maintaining the tonality, drive and emotional impact of a performance. I think the takeaway message is try it, you might like it. If you do, you're way ahead of the game. If you don't, then you might want to consider a lower gain active.

And w respect to Nelson Pass' quote- I agree completely w Larryi. And of course there are lots of people who have systems that do not meet the criteria for using a passive. For example, George's LSA (a great product, I own one) does not have source switching or a monitoring circuit. All passives have limitations with respect to matching upstream and downstream components. If you are of the camp that believes that eliminating the need to attenuate the source signal is the "ne plus ultra" of system building, then go passive. If you have other criteria, then go with them. Think of system-building as a design exercise (which of course it is). There are always design trade-offs. ALWAYS. Even in "cost is no object" kit. Your final design will be based on how you value the different elements involved in each trade-off. If cost:performance ratio and transparency are your most important design criteria then an LSA might be the way to go, and then you need to base the rest of your design around that element. If a control center providing source switching and RIAA equalization in one package is your primary criterion, but you also really value transparency and channel tracking at low volume, you might want to consider a full-function pre w a phono stage and a TVC. If you have to have source switching, an RIAA equalization circuit and a remote, then you're probably going to want an active w a motor driven volume control. Add transparency to the list and it's going to have to be a very high end active. Etc, etc.

Hi. Original poster here. I’ve been following this discussion with interest, and I didn’t know it would become so controversial!

A couple of thoughts:

Trying my DAC direct into my amps is certainly a good idea. I need to re-arrange my equipment so that my interconnects will reach both amps. I’ll try to do that some time this week.

Is the Luminous Audio Axiom a decent passive? It uses a conventional resistive ladder network for attenuation. It’s not a lot of money, so I won’t be risking much.

Finally, there doesn’t seem to be a lot of love for BAT in this group. I expect their next to top-of-the-line (at the time) would be pretty decent. If you disagree, please tell me why. Thanks!

"03-23-15: Slanski62
Hi. Trying my DAC direct into my amps is certainly a good idea. I need to re-arrange my equipment so that my interconnects will reach both amps. I’ll try to do that some time this week."

This is the most sane comment in this thread so far, as it will cost nothing, and the gains could be massive.

Cheers George