In line Attenuators with Passive Preamps

When I have used an attenuator, with an Audible Illusions MB3 and the 15db attenuated switch on my Lamm LL2.1 deluxe, it has been to reduce the gain by the said amount implied by the attenuator being used, I am not sure you will accomplish your desired goal other than running out of gain with the passive preamp you are using. 

Tooblue, yes, you may be right, at least in some circumstances. There are 10dB attenuators. If someone has a digital source outputting 3V, a 10dB attenuator would, if my thinking is correct, reduce the output to ~1V (Have not done the math). One volt may be enough to drive many amplifiers to the loudest desired level. There may be attenuators available that are of lower than 10dB attenuation. 

My primary concern is the capacitive issue when using a passive pre.

For what it is worth I had a set of adjustable attenuators made for me stepped in 2db steps so I could play around with things and also use as preamp per sey when driving a digital combo to my amp.

This might be what you are looking for!
http://www.schiit.com/products/sys

Donvito, Yes, the SYS is worthy product at it's cost. I own one and am currently using it. Need not get beyond 10 o'clock position for loudness. Was thinking I might remove so much potenteometer from signal path.

I believe I have over thought this issue. My best approach might be to purchase a better passive with different volume control. Luminous Audio with step ladder or Lightspeed. Will be used with a Nuforce STA200 or a Dynaco ST70 (original).  

My questions are: 1) Should a in line attenuator be considered when using a passive pre?

No not a great idea unless you know your I/O impedances are still good, as they will change depending (where you put them) the input or output impedance matching, always for the worse, than what you had without them when using your passive preamp..

The best resistance value for a passive preamp is series/shunt 10kohm.
This value is high enough input impedance to suit 99% of sources (except high impedance >2kohm tube output sources)
And low enough to suit most poweramps inputs that are 33k or higher.

Cheers George

Thanks George. I believe the SYS has a input impedance of 10K. In conjunction with the 51K input impedance of my Nuforce STA200, I have a combination having ~8.8K impedance. My source is a PS Audio Digital Link 111 DAC which has SS analog output. I haven't found an output impedance for this unit however feel safe it is very low. If, after exploring the use of a passive, and I wish to continue with this approach,  I will likely upgrade from the SYS and consider your Lightspeed. 

RE the in line attenuation, I have decided that I may have over thought this situation and no longer am considering the use of them. 

RE the in line attenuation, I have decided that I may have over thought this situation and no longer am considering the use of them.

I'm assuming the reason for asking about the inline attenuators is that maybe you feel your Schiit Sys volume control is coming on too fast still down low?
This could be a possibility if Schiit use a 10kohm pot, but a "linear one" and not a "logarithmic one", then it did only cost $49.
  
The Lightspeed is made so it behaves like a logarithmic pot, so it's volume will come on slow and build till you get to around 2o'clock after which it's volume increases far more rapidly.

Cheers George  

Thanks George! Exactly my concern. I am certainly interested in the Lightspeed. Yes, a logarithmic approach is what is needed with the gain and sensitivity of the STA200.