Thanks, but have you had any experience with the limitations of a passive pre-amp, if you read my original concern/question you will see my Source/Load situation that may need to be addressed (ie 10K pre-amp does nothing if it may not work adequately with the potential impedance matching problems I have). I still believe in the abundance of knowledge in the audio world I can still get a great working system given my choice of DAC.
This link may be useful to read, I just need some direction in where to find the right pre-amp:
http://audiokarma.org/forums/index.php?threads/passive-pre-table-regular-vs-haller-shunt.556704/
To anyone with an acquired knowledge of the combinations of source output impedance, potentiometer impedance and amplifier input impedance an how to properly implement these parameters and recommend the right product.
Thanks.
just use a 10K balanced passive attenuator. otherwise by a passive monitor controller. There won't be any loss, because the dac is not driving into a lower impedance load that would cause lack of bass response. btw the thread you are referring to is for an unbalanced circuit. The two types that are used are the PI atternuator ( also called "o" attenuator), and "T" type. Typically T-types are used for adjustable attenuators. The monitors are 10K on the input. That is why it states 10K. Also, you have to understand a couple of things about the output stages, the output impedance is the smallest impedance that will guarantee the specifications. Its always better to find the optimal load, on tl071, tl074, types 10K seems to be the optimal load and the norm in electrically balanced systems, but this is not a fixed point somewhere as 2K-10K is the final resulting impedance in an balanced chain (in your system, the terminating resistance on the output of the dac in parallel to the input of the genlecs that we put in parallel an attenuator). I've seen zillions of times interconnecting different pro gear, 600 ohms is the norm for transformer balanced systems this impedance interconnect is a fixed point. Btw, I wire radio stations, pa systems, and pro recording studios for the past 20 years. yes there are other impedances, but 10K is not going to cause the tl071 to pull excessive current and cause white noise, low impedance will. There's maybe 35 different studio setups I've done and about half of them have a 10K attenuators because of these powered monitors. I've hooked up your model before this way, along with Yamaha hs80, Neumann KH80... etc, all of those self powers are like this. So if I go by the 10X rule, the terminating resistance is 12.5K on the dac's output, then 10K is parallel, to another 10K and if we do the parallel formula, we get 3.57K as our ending impedance.
Just giving you some professional advice, recommendations, and a little bit of whats going on in the background for you....
edit: here is some light reading on the subject:
http://www.radio-electronics.com/in...n/attenuators/balanced-rf-attenuator-pads.php
and
https://en.wikipedia.org/wiki/Attenuator_(electronics)
Unless you want to build one out of some high end resistors (like z-foil resistors), a standard, off the shelf 10k attenuator is going to work.