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

 

 

 

 

dsper

@ditusa 

I get the horn monos with an all horn speaker.

I just worry that the amps would not drive the Forte's well given their 12 inch woofer and 15 inch passive radiator...

Will have to give Quicksilver a call.

 

@dsper Wrote:

I get the horn monos with an all horn speaker.

My speakers are hybrid with two 15'' woofers and a horn, system 4435. See below:

Will have to give Quicksilver a call.

I agree with calling Quicksilver and asking for their advice.

Mike

https://www.lansingheritage.org/html/jbl/specs/pro-speakers/1984-4430-35.htm