Preamps - Active, passive...???


I have seen a number of comments in magazines as well as on-line about preamps as an "unnecessary evil", (my words).

There are products such as Volume Controls and Passive Preamps that are supposedly designed to be as simple as possible; thereby changes to the signal are to be minimal. My question is, "Why then would you buy an active preamp, IF these "simplistic" devices are "better""?

Let me state that I am not ridiculing anyone for there purchases. I am in a state a flux in my stereo and the preamp department leaves me scratching my head. Such as, is something simple, such as a Plactte passive the way to go or a highly rated active preamp.

Thanks in advance for your comments.
brianmgrarcom
PULEEZE. search on "passive" in the audiogon search engine. you'll come up with 498 threads. these repetitive, cumulative queries are getting REALLY annoying, at least to me. have our moderators disappeared? sure hope so. -cfb
Brian

you will find enough reading to last you a fortnight on this topic by doing a search in the archeives under "passive".
All I will say is I have the Placette Audio Remote Volume control and it is THE most transparent sound I have heard in my system in 20 years. I believe as long as your system is refined and you use short interconnects fron preamp to amp, Placette Audio passive preamps and volume controls with their vishay resistors are simply the best way to hear everything your system is capable of. It adds nothing to the sound.
Go out and listen to some high quailty pre-amps. Tube,SS, does not matter. After listneing to some of the equipment built by CJ, Krell, ARC, Levinson and (just as important) others, you will give up on the passive fad.
I'm in the same boat as you, have been looking at pre's in the 3 to 6 grand range and the only thing I can find that an active (tube only!) pre can do better is the midrange bloom thing. that's it. everything else is bettered by a passive as cheap as the creek- the placette is probably 10 times better than the creek on top of it all. And the matching concerns are way over-blown in my experience and I'm not just talking about the source driving the amp to full power- forget it - try your cd player directly into the amp and you will have to leave the room! I'm talking about midrange solid immages and presence along with solid bass and perfect soundstaging and musicality (that is;as good as your source and speakers will allow). But taking all this into account weather anyone agree's with me or not, it's still really hard to want to give up any of that midrange bloom even if your amp is a tube amp helping out in that department! I am personally looking for a DAC with tube output and high quality volume knob and skip the pre and if I can't find one I will still do a tube DAC with the Placette passive volume control. Good luck
greatly improved dynamics from an active
better transparency from a passive
only you can decide which your own ears prefer
Bob, aren't dynamics a matter of impedance matching? (output, pre vs. input, power: ratio of 1:10 at least?)
learn a specification of your source components and power amplifier in terms of output voltage and input sensitivity/impedance first.

Some of the Cary amps as an example, have an input sensitivity of 9v, and there is no source component that I do know that can provide such an output voltage(up to 12V adjustable) to drive this kind of amp(s) without preamplification.

Almost all tube amps have impedance >=100kOhms and can be easily driven with passive preamp. SS can go as low as 10kOhms on the input; in this case you will not be able to setup a passive volume control for a sufficient amplitude bandwidth to control your volume with just attenuator.
But some SS-amp have input impedace >=50k which is sufficient enough to use with passive preamp.

Once you've jumped to the conclusion of having a passive preamp meaning that you've matched your source components and power amplifier, you'll need just to listen and compare. If you'll be dissapointed, there is nothing to worry about since most of the SS-output suorce components have a negative feedback applied to stabilize the output voltage which gives you a large lack of the dynamics(which is corrected by an active preamp). In this case the tubed output source components will be your best bet with passive preamps since tubes do not need an application of large negative feedback.

The source that I've grabbed this explaination is a)other audiogon forums, b)DIY experience c)listening experience. It is OK to ask a question(s) to get answers on New Today forums.
I've had passives for ~10 years now. I keep trying pre-amps from CJ, Krell, ARC, Levinson, and others. Some are nice but a well made passive in my system is more open AND more dynamic than ANY of the active units.

I've come to the conclusion that if an active line stage is required then there is something wrong with the system, typically the source component. Case in point : My Pioneer DV-05 with its wimpy power supply sounds better working into my MF X-Can v2 as a preamp than it does working into the passive. There is some loss of detail but the bass is better and presentation is punchier & more involving. However, my Muse 9 Sig definately sounds better working into the passive.

The source components need to have low(under~200 ohm)output impedances AND be able to source some current into say a 2K ohm load.

Not all passives are the same. I've had the Adcom line controller, Line Drive, Line Drive Deluxe, & TLC-1. However, my Reference Line Premminances 1 & 2 are the best by far. Full of bloom, detail and shocking dynamics (actually, they let all of that stuff thru without editorial change). They are cheap too (~$600-800 on the net)which makes them a low cost/risk try out. I'd love to try the Adcom GP750.

I've driven a passively bi-amped settup with over 6 meters of combined cable length with no problem. Just don't use funky cables with funky boxes & stuff and make sure your amp(s) has about 26 DB or more of gain.

Good Luck
I was on a search for a new preamp to replace a veiled and closed-in sounding Rotel RC995 and tried the CJ PV14 (tubie and slightly rolled off), Krell KRC-3 (dynamic yet slightly grainy and expensive), Linn Kollector (worse than the Rotel, wooly and fatiguing), Musical Fidelity A3cr (fairly transparent, a little bass bloom) and Levinson 380 (bright, grainy and expensive). Finally I tried the Placette Passive Line Stage and it was the only thing that didn't muck up the sound in some way. Some of the other preamps are quite good, like the MF A3cr, but all I was looking for was something that was sonically transparent (smooth extended highs, clean natural mids and deep powerful bass) to switch sources and change volume. This might not work in all setups, ie. 20ft interconnects to your amp, but if your ics are under 2m and your components can drive your amp louder than you'd ever listen, why not go with a quality passive?
Never used a passive preamp, but tried my Monarchy DAC, which, says the manufacturer, was designed for direct-to-power amp, straight into my Meitner STR-55 driving 93 dB Tannoys and quickly switched back to my active preamp. The system had enough volume without using the preamp, but as others have observed, bass was flabby and muddy (if loud) and dynamics severely compromised. Has anyone tried the Meitner Bidat direct-to-power amp? Regards, Joel Tatelman
...Dr joe made a good point for passive preamp lovers:
It is true that you can compromise at high volumes in details and dynamics. Depending on your speakers, it can be any part of sound bandwidth especially bass.
Since I do not turn on high volumes, I realy enjoy the passive preamp's transparency.
The best preamp is no preamp. I am useing Wadia 16i directly connect to Classe CA400 to drive Eggleston Andra speakers. It is very transparent. Less is more.
I tried to insert a very good preamp BAT VK50SE in my system, it didn't increase the dynamic, which proof to me that less is more! Also please remember that additional gear in the music loop only will degrade not improve the sonic quality!
If you have an excellent digital source, excellent cables, an excellent amp, and want the convenience of remote control, you owe it to yourself to try the Placette Passive Linestage. It is absolutely phenomenal, with the above caveats. No kidding.