LM3875, minimum input sensitivity (gainclone)

[mAJORD]

Hi peeps

I was wondering, if it would be possible to design an LM3875 gainclone amp with an input senstivity of line level.. in my case aiming for say 150mv/150k for a 40 watt output. into 8o , allowing me to hook a CD player straight up to it,

I would use Rin as the volume pot of course, as per NS typ applicaton schematic


If this is possible, can anyone think of major disadvantages?

the reason i ask this in the first place is, A. if i can avoid using a preamp in front of it i will , as im trying to make a very compact system. and B. i cant find any simple line level- typical 0.8v amp level preamp designs on the net that take my fancy.. nor find any decent pre-designed stereo preamp pcb kits ( so i dont have to make a PCB) , they seem to not exist, except in very complex form with bass treble balance controls etc , which i dont need!

so that leads me to a bit of a side question.. if i DO need a preamp, can anyone point me in the direction to a VERY simple but effective preamp to bring that level up to what ill need. ,

thanks in advance!.

Jimmy

[BlackDog]

Just use a volume pot. That's what most people do.
You don't need an active preamp at all.

Steve

[S.C]

for the pre amp problem, you should go to Solid State, or search here for some simple design.

[garbage]

you might want to check out DACT site for a preamp kit.

[peranders]

You can decrease the gain to 10 and increase it up to 300 (with bandwidth of 20 kHz). If you increase the gain you may experience problems with too high output offest voltages.