My thoughts on discrete vs slider type passive preamplifiers

Comment: Hi there.I have a Graaf gm 20 otl amp and a zanden 5000 dac,which has about 1 or2 db of gain,i was looking at the luminous audio Axium before i saw your unit.Can you tell me if your passive would work with my components? Also what type of volume control are you using,and how is your design different from the luminous unit?
Talk soon.Thanks Eddie

Answer:Hey thanks for your questions. I see no reason my passive preamps would not work with your setup. Most , if not all DACs can drive amplifiers to full power output if driven directly. That is the reason passive preamps work so well, unless of course you want a bit more PUNCH or some type of coloring of your sound. 
My 10K ohm passive preamps have a slightly warm sonic signature and my 50K ohm models are very precise, clean and open. Almost akin to having no preamplifier in the signal path at all.
The 10K unit use Bourns pots and a few other manufactures. I myself cannot distinguish between the signatures of them. They are as I’ve said slightly warm compared to my 50k units. 
As for the differences, I believe the luminous units are ‘switched’ resistor type. Meaning that they use discrete resistors and switch between them with a set of contacts. 
To what I prefer… Well I’ve done / tried both. I prefer the regular potentiometers. They may not be as perfectly linear as far as lower volumes go, but that can be compensated by simply adjusting the pots accordingly. I have also noted that most people don’t have perfect hearing in both ears. And room acoustics are not perfect. You can’t really ‘fine tune’ switched passive preamps. As they are fixed by the selections of resistors. 
With slider type pots you can adjust to any level. And as long as they are decent quality pots the sound will be very good, with the exception of playing music as very low levels. At low levels discrete components do sound better.  IMHO.
I listen to most music at mid to loud levels so at those levels discrete vs slider is almost imperceptible. 
I only have one 50k passive preamplifier made up right now at the moment and it is painted with a burgundy colour. I haven’t taken pictures of it or put it up for sale yet but if you’re interested I could take some pictures of it for you.

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