Good and bad w/ replacing stock preamp jumpers?

"My experience has been that when someone states

it seems as though there has been a sonic improvement

there hasn't been any change, just what they had hoped to hear."

Isn't that what happens when someone adds any new piece of equipment, whether it is a $10,000 amplifier or a $60 silver preamp jumper? You hope to hear something different and hope that difference is an improvement.

My experience has been that changing the preamp jumpers on my modest AMC SS integrated makes a very significant change to the overall sound of the system. At least on the same level as changing power cords, ICs, fuses or digital sources.

I have three types of jumpers that I can swap out: the stock metal bars, Audioquest premade PSC+ copper jumpers, and custom made silver jumpers. The sounds of these three are very different, and the two aftermarket jumpers sound considerably better than the stock bars.

I would describe the sound of the three jumpers this way:

-stock bars: brittle, compressed and "shouty"

-Audioquest PSC+: smooth, warm and a bit midrange heavy

-custom silver: Detailed, airy and a little forward

I have been listening with the silver jumpers in for a long time and have made several other modifications to my overall system in that period. I just yesterday put the Audioquest jumpers back in for fun and my immediate impression is that both the bass and treble lost some definition and the sound stage collapsed a bit as well. The flip side is that violins are not as edgy or etched sounding and the overall sound is more relaxed.

Since the Audioquest jumpers have been sitting in storage for a while, they probably need to warm up a bit, but the difference in sound between the silver and copper jumpers in this application is even more pronounced than I remember it, perhaps because other improvements in the overall system have allowed me to hear these differences better than before. In any case, my experience is that preamp jumpers can provide a noticeable improvement in experienced performance. And as with other cables, materials make a huge difference, even if it is only a 2-3" piece of silver in a sea of copper wiring!

I own a Parasound Halo based 2-channel system, a P 3 preamplifier, A 21 amplifier and D 3 universal disc player driving Paradigm Reference Studio 100 v.4 speakers. I recently upgraded interconnect cables from 1.0m BetterCables.com Silver Serpent II RCA and XLR to 0.5m PS Audio xStream Transcendent XLRs. The Transcendent cables use solid silver wire. I also upgraded my speaker cables from BetterCables.com Premium III bi-wires to PS Audio xStream Resolution Reference 10 gauge PCOCC bi-wires and replaced the stock power cords on all three Parasound pieces with PS Audio xStream Plus SC 10 gauge PCOCC cables. When I did so I noticed my P 3 preamplifier had jumpers between the preamp in and amp outs that looked to be simple chrome plated U-shaped pieces of some indeterminate metal. From their stiffness and the sound they make when you drop them I suspect they are some sort of pot metal. I looked at commercially available jumper cables and did not like any I found. The Parasound jumpers do not have RCA jacks but merely connect the center pins of the preamp in and amp out.

I looked up the spec for the RCA center pin and found it to be 3.2±0.1mm or basically 1/8". I found a source for .9995 1/8" silver rod and purchased a foot at $5 an inch. I then cut 2 pieces 2.5" in length (the length of the U-shaped pot metal piece when rolled on a ruler), bent them to shape using pliers and polished them. I put them in my system last week and could not believe what I heard. I had to swap them out several times to see if what I was hearing was real or imagined. It was real. I played a song I am very familiar with, the opening track from Sarah McLachlan's Afterglow Live. What I heard was a deeper soundstage placing Sarah closer to me and her backing band further back with airier high frequencies and deeper, tighter bass. I consider the difference as significant as that I heard after changing the other cables. During the last week I have been enjoying my system immensely and notice subtle differences for the better with each recording (CD, SACD, DVD-A or LP) that I play.

The upgrade definitely improved my system especially considering the $25 price tag.

Martin

IMHO... Its all about conductivity. Most of the stock jumpers you see are plated with nickel which does not give you the conductivity you get from pure copper, gold plated copper, silver plated copper or pure silver. Nickel may have a sound characteristic that people desire, or are use too, in some amps, (there lies the subjective nature of wire) but in my experience, the better the conductor = a healthier signal to amp = improved sound stage. Even cleaning these in out jacks makes a big difference. Again, this is just my experience with my ears..
James

I love these responses. I am also a believer in everything matters. I think some percieved differences in sound quality are very slight and may not even be happening and certainly not measurable. However, there is no denying many of us claim to hear changes where others say is impossible. Like art our own perceptions vary greatly. Synergy and the human body are things no one understands completely. I think we should all agree if we think something is happening than it just may be and even if it is not, tweaking is a lot more fun.   

I tried the Audioquest RCA pre-amp jumpers and could not hear any discernible difference between them and the metal pins that came stock on my McIntosh MA6900 integrated amp. For reference, the metal pins are insulated and looks a lot like these here, except they are gold plated and stamped McIntosh. I was hoping for something as it would have been an inexpensive upgrade. Alas, nothing.