Modern Linestages

Active preamps are to me a dinosaur left over from the analogue days, when one needed an riaa stage in the preamp and then another gain stage to get the voltage up to the input sensitivity of the poweramps they were to drive.
Today's sources cd, tuners, ipods, phono stages. etc: have enough output to drive the poweramps directly even into overdrive.
So all that's needed is an attenuator between them to attenuate the level, there is no need for active preamps with gain stages as there is no gain needed between today's sources and poweramps.

Cheers George

The secrete to having the perfect passive attenuator without losing or adding anything to the sound of the source (being true to the source)
1: Is to make sure the sources ouput impedance is 5 x or less the attenuators input impedance.
2: To make sure the power amps input impedance is 5 x or more the attenuators output impedance.
This then will give you the sound that you would get if you pluged the source directly into the power amp, yet with control over the volume.
Cheers George

"08-22-11: "Unsound
While I understand that passive pres are more system dependent than active pres, I find it interesting that some would suggest that simpler is better and yet choose a system that doesn't maximize the potential for a passive pre.Unsound"

You can try this experiment yourself, put your cd straight into your poweramp and play a known quiet starting disc, so you can stop it before it gets too loud.
This is the purest way you will hear that disc, any active pre in the system will sound different to this as no active pre is a straight wire with gain, they all have a signature to their sound, call it coloured, or distortion they all sound different, none sound like the direct conection between the source and poweramp. The passive pre will if implemented right sound the closest and the truest to the source. You may not like that purity of sound, you may wish to introduce an active preamp that gives you the colouration your seeking to counteract a problem elsewhere in the system, but this is an expensive band-aid fix

Cheers George

No that implies that a correctly implemented passive will be true to the source, just like a direct source to poweramp connection is the best you can get.
It's up to you to get the best source you can. Then if you have to spend $15,000 -$35,000 on an active preamp to change the sound of the source, then you are colouring/distorting what the source gives, and all you are doing is an expensive bandaid fix of the source.

Cheers George

TBG back a few posts
http://forum.audiogon.com/cgi-bin/fr.pl?aamps&1313773451&openfrom&51&4#51
is the way one would make sure he/she has properly implemented a passive.

Cheers George

Grannyring: George, I like your passion and I do see things differently it seems :Grannyring

Nope, no passion here with this, it just Ohms Law, Kirchoffs Law, and the maths that goes with it.
The passion comes as a result of listening to the music through the purest most transparent form of controling volume there is, and there's no voodoo at all involved.

Cheers George

"Charles1dadYou could certainly conclude also that the passive units are`nt passing the"complte" signal,thus there`s some degree of subtraction of musical information.Charles1dad"

This statement is not correct and only valid if one has not implemented the passive correctly.
As I've stated in my 2nd post on the 08-22-11, if followed then you will get it "all" as the source wanted you to hear it, even more than any actives preamps.

Once again here is the impementation that's needed to make a passive become electricly transparent to the source.

1: Is to make sure the sources ouput impedance is 5 x or less the attenuators input impedance.
2: To make sure the power amps input impedance is 5 x or more the attenuators output impedance.

Cheers George

Grannyring you go on that a good active preamp can mystically make a system sound "better", yet you deny the fact here and in other posts that it will be coloured or adding distortions to change this sound for the "better" You cannot have it both ways Grannyring.
The prefect preamp has be always touted as being a "straight wire with gain" this says no colourations and no distortions and to be "true to the source". A properly implemented passive comes closest to this, and direct connection from source to poweramp is a "straight wire but with no gain" as it is not needed.
If you think your source "sucks" then change it for the better, don't try to band-aid fix it with a $30k preamp.
The best quote in audio history was made by Ivor Tifenburm of Linn Sondek fame, "the most important part of a system to get right first is the source".

Cheers George

"08-25-11: Liguy: The perfect linestage can be imagined as simply a wire with gain. If you do not need gain a passive preamp will do. So, you ask what about matching impedances? Well a simple buffer can be used. Enter the First Watt B1, a passive volume control with buffer. The buffer makes the passive preamp more versatile because the impedance issue is handled by the buffer. Expensive? Not in the least and very good sounding. Here is Nelson Pass's thoughts:Liguy"

Nelson Pass first designed that buffer for my Lightspeed Attenuator (passive attenuator) in early 2008 on "diyaudio" forums, it was so the Lightspeed could drive some of his very low input impedance amps that were 10k-30k input impedance that he and others were making. With his/others amps that are 47k and over there was no need for the buffer as the best sounding buffer was no buffer.

Cheers George