Pani, from an earlier discussion; you may find it helpful:
Frogman, very interesting post! Thank you.
I have been struggling with the same idea of eliminating
(at least one of the) RCA-RCA joints: I'm thinking
of rewiring my SME3012R with AN wire ommiting the SME
RCA base, leaving a +/- 1m continous run of the cable from the arm's cart socket, terminated with an RCA at the input of my DIY EAR834 (I'd like to keep at least some flexibility and not solder the wire directly to the SUT).
The problem I have is how to properly make the cable from the tonearm base on. There are 2 problems I see:
1) The wire is super thin, how to make the cable robust enough having good electrical parameters? What I'm thinking is as follows:
AN twisted pair -> 16ga teflon tubing -> PTFE foam sealant tape 5mm thick to add space -> heavy copper braid as the screen -> shrink tubing terminated with Vampire 800C RCA
2) How to fix the cable at the toneram base so that cable manipulations will not affect the thin AN wire (some soert of strain release)?
I'm curious of your thoughts. Did you also wire your EAR input and SUT's with the AN wire?
Hi Bydlo, IMO you are on the right track. I also put twisted pairs of the AN
in Teflon tubing, EACH covered with a copper braid shield, then covered
with polyester braid in order to insulate the copper braid and for aesthetics.
I suppose you could use a single copper braid tube for both pairs of wires
(in Teflon). If you use the copper braid, you should make provisions for
connecting it at the preamp end to the grounding lug of your EAR. I
soldered wire pigtails with spades to the braid.
Please keep in mind that I am not familiar with the construction of the SME;
but I have done this to a Syrinx PU3. For strain relief at the base of the
tonearm what you suggest would work, but foam tape tends to deteriorate
over time and can be messy even when new. I would be inclined to (after
completing the construction of your "phono interconnect") use
pieces of increasingly wider diameter shrink tubing around the first, say,
1.5-2 inches of the portion of wire in Teflon tube/braid, until you can get a
fairly tight fit inside the portion of the arm (pillar) where the wire exits arm;
leaving about one inch, or so, outside the arm.Then, use heat shrink tubing
to secure this exposed portion to the arm pillar itself. Once you terminate
the wire at the other end with RCA's and use appropriate strain relief there,
the entire length of AN should be well protected from strain.
A couple of other thoughts: I soldered the AN wire directly to the circuit
board of my EAR, also bypassing the SUT's since I have been using MM's
almost exclusively lately. Also, if your set-up and particular environment is
clean of EMI/RFI, I suggest you don't shield the wires. Mine, as I said, are
shielded, but that is because I have issues with EMI/RFI in the urban area
that I live in. I have found that the wires sound best un-shielded if you can
get away with it. Lastly, if you have not worked with AN before, I found that
the best way to solder the wires is to first tin the ends by running the wire
through a bead of molten solder on the tip of the iron; not too hot as it can
actually melt the thin wires along with the insulation.
Good luck and I think you will be very pleased with the sonic results.
Hey Frogman! Thank you for your reply. One correction: I wanted to use 5mm PTFE foam tape around the whole cable.
I'd ike to have some "high quality distance" between the teflon tubing with the AN wire and the braid. In other words, I'd prefer not to put the braid directly outside the teflon tubing carrying the wire. The reason is to minimize with a the capacitative coupling between the wires and the shield. At this level of signals all the dirt from the ground may couple via the shield to the signal.