Hi friends,
First of all I want to explain my sound system and situation after that I will ask my suggestions.
My source is: Clock Modified Asus Xonar STX having 100ohms output impedance
My preamp is: DIY Aikido 12vac with stepped attenuator and input selector in front of it. (I dont know but this also have low output impedance, like my source)
My poweramp is: DIY 2x bang&olufsen 125asx2 modules bridged using a unbalanced to balanced converter in front of it. (10kohm input impedance)
My problem is with Aikido line stage has a slight hiss in the background that I can not solve, and when I connect my source directly to the poweramp I feel the music is much more neutral and natural. I like it more, but when I connect my source directly to poweramp there is too much gain so simply I cannot set the volume up to %10. I also need input selector because some times I switch to Playstation and TV
SO I need an active or passive preamp in front of my power amp simply to control several inputs and volume.
Last several days I read nearly all of the from post is the "analog line level" forum but I can not find the answer.
If I use passive preamp, because of the low input impedance of my DIY poweramp, I think I can not get proper results.
IF I use active line stage, this time there will be unnecesarry gain and I dont want this.
All I want is extremely transparent preamp to use as input selector and volume controller.
Stepped attenuator + buffer is a way to go? Or only passive pre?
Should I use LDR based passive pre?
OR nelson pass b1 is a good choice for me?
I am so confused
need immediate help 
First of all I want to explain my sound system and situation after that I will ask my suggestions.
My source is: Clock Modified Asus Xonar STX having 100ohms output impedance
My preamp is: DIY Aikido 12vac with stepped attenuator and input selector in front of it. (I dont know but this also have low output impedance, like my source)
My poweramp is: DIY 2x bang&olufsen 125asx2 modules bridged using a unbalanced to balanced converter in front of it. (10kohm input impedance)
My problem is with Aikido line stage has a slight hiss in the background that I can not solve, and when I connect my source directly to the poweramp I feel the music is much more neutral and natural. I like it more, but when I connect my source directly to poweramp there is too much gain so simply I cannot set the volume up to %10. I also need input selector because some times I switch to Playstation and TV
SO I need an active or passive preamp in front of my power amp simply to control several inputs and volume.
Last several days I read nearly all of the from post is the "analog line level" forum but I can not find the answer.
If I use passive preamp, because of the low input impedance of my DIY poweramp, I think I can not get proper results.
IF I use active line stage, this time there will be unnecesarry gain and I dont want this.
All I want is extremely transparent preamp to use as input selector and volume controller.
Stepped attenuator + buffer is a way to go? Or only passive pre?
Should I use LDR based passive pre?
OR nelson pass b1 is a good choice for me?
I am so confused