2. tech-talk
  3. 999049858

Problems with Passive Preamp, please Help

I recently added a single input pre amp to my system and even with the volume turned all the way up the sound level is not what I would call loud, it sound like it is in the 11oclock position in most systems, I was wondering if this is a component matching issue or if it could have anything to do with my large room and small speakers, my system is a CAL CL10 (3v output) to an Anodyne passive (the only spec on the passive I could find was 5.50k writtn on the bottom), into a Marsh A400 (input impedance 56kohms for unbalanced, input sensitivity 1,4 Vrms), into Castle Severn 2s (single 5.5" mid/woofer, 1" tweeter)
mkaes
mejames
986 posts
 
what length Interconnects are you using? Passive dictate the use of short [2 meter] or less length interconnects.
Ag insider logo xs@2x
audiophobe
3 posts
 
The CAL is a tube DAC? If that is the case, then 5.5K is probably way too low. I have heard that tube output stages commonly require more like 50K or even 100K impedance on the passive. I have run into this myself when using a 25K passive with a CJ dac: the sound lacked bass, and generally sounded small and compressed. When I changed the (very expensive) passive to a cheap home made one that was 50K, there was a huge sound improvement.

Hope this helps. Passive preamps are a real bear to get working sometimes.
marakanetz's avatar
marakanetz
5,473 posts
 
I think that there is nothing wrong with impedance matching. the input sencitivity of the power amp has to be <=500mV@1Khz in order to be able to operate 3V output from DAC with passive preamp.
More to discover