I decided to take a cue from Roger Russell and rewire my SDA SRS 1.2TL's with Cardas copper Litz wire in 15.5 gauge. The Cardas wire is slightly larger than the stock wire, which is 16 gauge. This Cardas wire is the same wire that Mr. Russell uses in his $18,000 IDS-25 loudspeaker system. However, Mr. Russell does not believe the Cardas wire offers any sonic advantage over ordinary wire. He just uses it for marketing reasons. [Link: Cardas wire and the IDS-25]
There is nothing wrong with the stock wire. I just wanted to see if the better wire would make a difference in this application. The Cardas wire is a lower noise design due to the Litz configuration (reduction of strand interaction by insulating individual wire strands) and due to the polished surface of the conductors. AudioQuest uses similar technologies in their cables.
The wire was conditioned for four days (96 hours) on the Audiodharma Cable Cooker prior to assembly.
The Cardas wire measured better with respect to conducted noise, but actually sounded much worse than the original wire.
Figure 1. Main ingredients: wire and connectors.
Figure2. 1/4" WBT quick disconnects, which are gold plated copper.
Figure 3. I found that I could use the WBT disconnects with the narrow tab on the RD0198 tweeters if I
gently pried up the middle band on the back of the disconnect and insert the tweeter tab under it.
Cardas wire has each individual strand coated with a clear polyurethane varnish. I tried two different Dremel attachments to remove the varnish:
428-Carbon Steel Brush - "Remove dirt, rust, and corrosion from most surfaces. Clean electrical connectors and other metal parts, remove buildup from faucets, clean camp stove burners and more."
530-Stainless Steel Brush - "Use on stainless steel, pewter, aluminum, silver and other white metals. Use for cleaning, deburring and surface finishing."
The carbon steel brush worked faster and better.
Figure 4. The carbon steel brush is attached to the Dremel. The stainless steel brush is at the lower left.
The work surface is the bottom of an aluminum baking pan.
Figure 5. Driver wiring harnesses - Cardas on left, original on right.
Figure 6. Tweeter wiring harness.
Figure 7. Binding post and SDA inductor wiring harness.
Figure 8. Cardas wire installed in the right 1.2TL.
Grinding off the clear, invisible insulation from each end of a piece of wire was a very tedious process. Added to that was the need to test for continuity with a multimeter after grinding.
Figure 9. Cable Cooker output signal.
Figure 10. Cable Cooker output signal from original internal wiring.
Figure 11. Cable Cooker output signal from Cardas wire after four days of conditioning.
The conditioned Cardas wire showed less ringing than the original wire.
The right speaker was done first. However, since the results were not favorable, Cardas wire was not installed in the left speaker. With Cardas wire in the right speaker the following sonic results were obtained:
1. The sound stage on the right contracted 4 feet.
2. The right side sound level was apparently lower.
3. Less tactile sensation on the right side.
4. Less image weight on the right side.
5. Less bass definition on the right.
6. Less overall detail on the right.
7. Less tactile sensation on the right.
I was expecting the Cardas wire to either sound better or the same as the original wire, not worse. I don't mean to discourage anyone from using this wire as many people, even members of this forum, have achieved good to excellent results with it. It just didn't work for me in this particular application.