Feeding an integrated amp with a preamp

will I listen to just the amplifier section of the integrated amp?

depends on whether you use an auxiliary input or a main in which bypasses the volume pot (not a great deal of difference really).

you will simply be feeding the LFD with an additional gain stage. If the LFD gain structure is adequate you will gain nothing. I would imagine the LFD is competently engineered in that regard.  

Unless you definitely know that you are failing to achieve full rated power out of your amplifier due to inadequate gain (highly unlikely) I wouldn‘t bother. You will probably just add another veil to the sound.

You could with a switch on my KA-4002.  

That LFD Integrated amp is a very highly regarded, world-class integrated amp from about 15 years ago. It is purposely a very simple, minimalist architecture in order to not have any components that may taint the sound quality. If it is in proper working order, I doubt that adding an additional pre-amp in front of it is going to improve the sound.

I think that would be a mistake, and not yield very good results.     The integrated needs a fixed output from your sources .   By driving the int with a preamp,   you are likely to saturate the integrated amps input with way more than the "standard" 2.0 volts or so output that the integrated amps inputs.   So in addition to too much gain,  you now have two volume controls in the mix .... that can't be good. 

Unless you’re after some functionality that the LFD doesn’t have, there’s really no point in doing this. But if you want to do it, feeding the integrated from the Tape Out jacks on the Bryston will bypass the Bryston’s volume control and gain stages, and enable you to avoid saturating a line-level input on the integrated. That would work best.

Thank you all for your input! There is nothing wrong with the LFD, actually I like it a lot. I was just curious about the outcome feeding the integrated amp form a preamp.