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Rega RB 250 Tonearm RewireNOTE: if you follow these instructions, it is at your own risk. Please do not hold me responsible for anything that goes wrong. Be very careful of your tonearm bearings. Do not exert any force through the bearings (like holding the tonearm base and wrenching on the tonearm tube!). I bought a Rega RB 250 tonearm new from Origin Live complete with their structural modifications. I chose to do the rewiring myself, both because I wished to save money, and because I wanted a simpler philosophy than their rewire. Rather than rewiring the tonearm only, and keeping the interconnect from tonearm base to phono amp, I wanted to use the tonearm wire all the way from the cartridge to the phono amp. This will eliminate one solder joint. Also the signal will be able to stay in the very fine wire all the way to the phono amp. For very low voltage signals (the Shelter 501 moving coil cartridge has only 0.4 mV output), I believe a fine wire to be superior to big fat wires. Said another way, what you gain in resistance from the thin wire is less important than what you lose in inductance (and perhaps capacitance). I bought four feet of each color Cardas 33 gauge tonearm wire and a Van den Hul cartridge clip kit from Michael Percy. In keeping with the "less metal is better" concept, I used Radio Shack 274-319a RCA phono plugs which are very light, some metal, lots of plastic. I read thoroughly the article on rewiring the Rega tonearm at Hi-Fi.com but this link is not stable. Most of Hi-Fi.com has disappeared. First I had to buy a new Allen wrench set that included a 1.5 mm wrench. I unscrewed the Allen screw at the base of the tonearm and removed the black plastic plug. I unsoldered the five wires (four signal wires and a ground) and removed the Rega interconnect. Using the soldering iron, I stripped the insulation from the end of the Cardas wire. It is difficult to effectively remove all the insulation and to tin the wires. Unlike the Hi-Fi.com article, I decided to try using the original wires to pull the Cardas wires through. So I soldered the Cardas signal wires to the original tonearm wires that emerge from the tonearm base. I was going to try and keep the Rega ground wire, which is attached to the tonearm tube and comes down through the mounting base. I pulled out the rubber stop at the end of the tonearm tube next to the cartridge (pull out the center plastic plug first, then the rubber stop). I pulled the four original signal wires at the cartridge end of the tonearm and started to draw the Cardas wire into the tonearm base. I attempted to keep a grip on the Rega ground wire, but lost it. Next time I would solder a wire to this to anchor it. As I pulled the original signal wires through, the small rubber tube got pulled out of the tonearm base and into the tonearm. I didn't worry about it. Being very gentle, I managed to get all the four Cardas signal wires successfully through. However my Rega ground wire was pulled into the tonearm and I couldn't retrieve it. The tonearm is now "ungrounded". I also did not follow the Hi-Fi.com advice about adding a fifth wire for a ground. Maybe I should have done that. If doing this over again, I might buy a fifth section of Cardas wire to use as a ground (in case I lost or broke the Rega ground). Now I unsoldered the Cardas wire from the original wire. I removed the rubber stop and threaded the tonearm wires through it in a configuration to match the new cartridge pins and pushed the stop back into the tonearm. So now my four signal wires are through. I soldered the cartridge clips on (tinning the clips first with the clip in an "upright" position). Then I pulled the wires back through the tonearm until there was about 25 mm of wire left poking out. Next I took two 3 foot lengths of 30 gauge solid copper hookup wire and soldered these to the inside brass base of the tonearm. Then I pulled the two left channel signal wires and one of the 30 gauge ground wires tight together, cut them off to the same length (3 feet) and put the three wires into the chuck of an electric drill. I wound them together until they were lightly twisted (approx. 2 to 3 twists per inch). Then I repeated this for the right channel. Then I soldered the phono plugs onto the two signal wires, leaving the ground shield unattached at that end. Finished! I hooked up the tonearm and immediately noticed an improvement. The music appears louder than before, as if more voltage is making its way through to the phono amp. Tone and harmonics are wonderful. Vinyl is now supremely satisfying. Beautiful!! Top
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