Good and bad w/ replacing stock preamp jumpers?


In the past several days I replaced the stock preamp jumpers on my integrated ($2800 retail) with aftermarket jumpers. I was told once by an audiophile he felt that removing the stock jumpers on my integrated (the amp in question was an expensive one-$5k) for aftermarket jumpers can change the tonal balance of an integrated, thus changing the designers intended sonic presentation. What are your thoughts on this? What's your experience with aftermarket jumpers? Also, aren't the preamp jumpers perfoming the same function as interconnects do between a separate preamplifier and separate power amp? And if they are, why do most of these manufacturers use cheap pieces of metal to connect an integrated's preamp to amp? This occurs even in some of the better more expensive integrateds? Why not provide a quality connection that could conceivably improve the sonics of the unit? I've read where audiophiles with integrateds routinely replace these cheap metal jumpers with a quality interconnect and gain improvements. It makes no sense that a manufacturer spends the money on R&D to build a quality integrated with quality parts and then compromises it with a poor quality connection between the preamp and amp when there is all this hubbub in audiophilia about better and more exotic interconnects that will take your system to the next level. If the quality of interconnects are considered by almost everyone in the audio world to be so vital to an audio systems performace why is the quality of the preamp jumper no less important? Or am I way off base here? Thanks for your perspective.
foster_9

Showing 1 response by mhconley

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