integrated amp - jumper between preamp and amp

[sarcasm]There will be a HUGE difference, but only if you also replace all the fuses with some of those "audiophile" ones.[/sarcasm]

In all seriousness, there is no objective difference in the sound by changing those jumpers. None.

@mofimadness +1      Emphatically, it always makes a difference AND improvement.  From the beginning, replacing horseshoe shaped steel bridging pins on an NAD 3120 dramatically improved everything.  Do it, report back.  Smile.

This was a while back, but I found it to be a fairly significant upgrade on my NAD 375BEE. It is a cheap tweak, give it a try.

The verdict so far: no consensus. With input from Audiogon and other research, my impression is that aftermarket jumpers range in price from a few dollars (DYI) to many dollars (e.g., AudioQuest or solid silver). What may shine through the diverse comments is that in some systems, there may be some change, which some who experience the change say is a good change. So, no consensus and a caveate: your experience may vary from that of proponents and naysayers, based on your system and preferences. I appreciate all the responses which have helped me think through taking the leap into after-market jumpers, and how much moolah I want to invest.

If you have a pair of RCA interconnects, plug them in to see if you notice anything. If you like what you hear, then you can consider buying a shorter "jumper" set.

The good news is that McIntosh had the wisdom to do this with jumpers instead of a mechanical switch with internal circuits.