Playing with Klipsch Forte iv's and Zu Soul Supremes right now.
Impedance and Sensitivity
Hi All,
I have made a move from inefficient speakers and large amps with high current supply to smaller amps and more efficient speakers. Think like 300 to 500 WPC at 8 ohms changing to 25 or 50 WPC at 8 ohms and speaker efficiency increasing to 98 or 100 Dbl from 87 Dbl.
I have always kept an eye on the output impedance of the preamp compared to the input impedance of the amp. I understood that if the input impedance of the amp was not at least 10X of the output impedance of the preamp, I could experience a negative impact on the bass response of my system.
As I try different preamps and amps with more efficient speakers, I have run into a new problem. This problem is that the gain of one of my preamps is 26dbl and, pairing it with a tube amp with an input sensitivity of 0.5 volts, results in not being able to adjust the preamp volume control so that my system plays more quietly. I run out of clicks for it to play more quietly.
I realize that either a preamp or a amp change can fix this. Not sure if in line attenuators is an answer as I suspect it adds a distortion or tonal coloration.
In the meantime...does this "gain" imbalance impact sound quality or is it just a loudness problem?
Thanks for listening,
Dsper
Showing 5 responses by dsper
My CJ 17LS2 is probably twenty years old and has 26 dB gain with no switching to a lower gain. My CJ LP66S tube amp (50wpc) is also about twenty years old with 0.5 V input sensitivity. Interestingly, my newer First Watt F7 is 0.53 V input sensitivity and 25 wpc. I was thinking that, for example, a pair of Quicksilver mid monos at 1.5 V input sensitivity might do the trick. My problem is that I do not know how to relate amp input sensitivity to preamp gain. One Volt less of amp input sensitivity equals how many preamp dB? Whoopee, this is fun! Thanks for listening. |
Benjamin at Mojo Audio, who made my DAC (1.5 V), also suggested that a passive might be the way to go. I do have a Luminous Axiom passive that I can try.
Can you share your thoughts on why the horn mono's would be a better choice than the mid monos? Everyone, I appreciate the feedback. Thank you! |