I recently came down with a case of the DIY bug. I wanted to do something fast and affordable to satisfy my itch, and I needed to replace my old IC's. I had ordered a set of RAM Electronics Silver-Flex RCA cables http://www.ramelectronics.net/FLEXSA.aspx. Nice interconnects, but the two cables are bound together close to the ends. The plugs cannot be separated apart more than a few inches without damaging the jacket, thus preventing me from connecting them to my Emotiva amp. I figured I could build my own to get around this, and maybe even up the quality.
After extensive research I settled on Jon Ritch's "Belden 89259 DIY Hi-Fi Interconnnect Cables" on diyaudioprojects.com.
This project uses Belden's 89259 RG59U Coax cable and allows for your choice of RCA plug, solder, and jacket. I went with the following for my 2 meter cable pair.
- Belden 89259 Coax (13 ft.)
- Cardas GRMO Rhodium over Silver RCA Plugs
- Cardas Quad Silver Solder
- Techflex .25 in. Expandable Sleeving- red
- Heat Shrink 12mm 3:1 6 in. x 4- black
- PVC Electrical Tape 1/2 in.- multi-color
- Soldering Iron
- Measuring tape
- Utility Knife
- Digital Multimeter
- Vice Grip
- Phillips Screwdriver
- Hair Dryer
1) Prep cable- I straightened the Belden Coax, then measured and cut two 2 meter (~6'6") lengths. I cut back the outer jacket on one end of each cable, combed back and twisted the copper shield, and carefully cut away the white insulation from the center conductor. I was careful not to touch the center conductor with the razor, exposing only about 3/8 inches.
2) Prep plugs- Using a phillips screwdriver and a hammer, I centered the tip of the screwdriver on the top of the narrow bridge on the plug. I tapped the screwdriver gently with the hammer until the bridge was bent in far enough to accommodate the copper shield.
3) Solder plugs to one end- I set the vice grip to hold the spliced coax cable still. I fed the copper shield over the top of the bent bridge and fed the center conductor in to the tit of the plug. I soldered both by holding the tip of my iron to the top of the copper while feeding the solder till enough was applied. Gravity pulled the melted solder down around the copper and filled the bridge and the tit.
Tip: Cutting about 1/8 inch off the end of the twisted copper shield will improve visibility of the center conductor and tit. It will also allow more room to get the tip of the soldering iron and solder in to the center of the plug.
4) Add Techflex and heat shrink- I slid the open end of the coax cable into the heat shrink and cut it about a half inch short of where my splice began. After doing this for both cables I cut four 3 in. pieces of black heat shrink. I slipped both the Techflex and two cuts of heat shrink over each cable.
Tip: I would recommend cutting the Techflex long enough that it slides up in to the plug barrel on both ends. If it is cut a bit short, as was mine, it will show through the heat shrink. Fortunately, I was able to hide this with some PVC tape later. Also, if you want to use red or white heat shrink to indicate Left and Right cables I would install it in this step. My 1/2 inch heat shrink would not fit over the Cardas RCA plugs once they were soldered.
5) Repeat step 1 on the unfinished end of each cable.
6) Repeat step 3 on the unfinished end of each cable.
7) Install heat shrink- I pulled the heat shrink 1/2 inches over the barrel of the plug. After making sure that all four ends were even I heated and shrank it with a blow dryer on high setting.
8) Label Left and Right cable- I used red and white 1.25 cm PVC electrical tape to indicate left and right cables by wrapping it around the heat shrink just behind the back of the plug barrel. This gave the cables a plastic-like looking ring which I think gives them a nice finishing touch.
9) Test for shorts. Using a digital multimeter I tested both cables for a possible short.
10) Plug and enjoy! This was a fun project. I was able to complete it in one afternoon once I had the parts. If I wouldn't have been taking pictures I would guess that two hours or less is all it would have taken. My wife had the bridge camera, so all of the pictures were taken with my phone.
How do they sound? Well, they sound terrific! And because I made them myself I believe they sound as good as anything I've heard, DBT and measurements pending of course. :T