DIY: Music Hall MMF-2.1 Tonearm Rewiring

This month’s DIY project wraps up something I started a few years ago. I’d purchased a used Music Hall MMF-2.1 turntable from a fellow member of a forum I frequent. I knew that the cartridge clips had snapped off, and one of the wires had broken off at the end of the tonearm near the headshell. Well, it certainly was broken off when I got it! The wire was too short to attach another piece to, so that meant one of two things: 1) get a different tonearm, or 2) rewire the tonearm. What’s it gonna be, Santa Claus?

As for replacing the tonearm, Music Hall wanted $150 for a replacement. Not only was that a bit steep, it was more than I had paid for the table! The MMF-2.1 sells new these days for around $300, so roughly half was in the tonearm. (Or as I’ll explain later, half the price is in marketing…)

My other replacement option was to find a used Grace G707-II tonearm, the same one I have on my “big rig” turntable, and just use that. Thing is, complete G707s are hard to come by. The anti-skating weight or line are often missing, or the cable, or whatever…I rarely see a nice one that is complete. A Rega arm would be good as well, but they are in demand, and expensive. Too expensive for this project, at any rate! Other arms I looked at did not have the high quality I was looking for.

So, that left rewiring.

I had no idea how to go about it at first, since tonearm wires are notoriously thin, and notoriously fragile. Especially these! I did not want to take apart the tonearm either–I could have removed both pivot assemblies, but I did not have a correct spanner wrench to undo these, and did not want to botch up the arm by using whatever I could find.

And then, where would I get the wire? Electronics stores would want to sell me an entire spool of wire, and I need four colors (red, white, blue and green). I looked around online, finding a source for tonearm wiring as a set, but it would have set me back about $15. This had to be a low-budget fix.

Enter the Pack Rat. That’s me. Several years ago, someone gave me three free computer mice, and as I shortly found out, none of them worked. (They were returns.) Someone mentioned that I should try the mouse cable. That I did! I snipped off one end, removed the insulator, and found six strands of very fine wire–two white, one brown, one orange, one blue and one green. Orange was close enough to red for me. So, now we had our wire!

But…how would we get the wire through the tonearm tube? You can’t shoot pool with a rope. And you can’t shove flimsy wires through a tube, no matter how hard you try. Digging through my hardware, I found some picture hanging wire: that strong, braided wire that you use on the back of framed pictures. I cut off a length, and I was all set.

Now we just need some patience. And good eyesight. Despite being short of both, I managed to get the job done with minimal fuss. I’ll outline it here in steps, in case you have your own MMF-2.1 tonearm to rewire. Wish I’d taken pictures, but such is life. You will need a #1 and #2 Phillips screwdriver to remove parts of the turntable, a couple of small jeweler’s flat blade screwdrivers, a low-wattage soldering iron and solder, a desoldering bulb or wick, wire cutters, tweezers, and needle-nose pliers. You’ll need the new wiring, and also a length of wire or cable that is stiff enough to push through the tonearm tube, and yet slim enough to fit through the openings. (Picture hanging wire, a guitar string, etc. are all good choices.) Also, if you have a small work vise or holding clamps to hold a wire and connectors, that will help you assemble the pieces again. Finally, a multimeter will help you test your finished wiring.

Here’s the procedure:

  • Remove your cartridge! No, don’t cover it up, don’t remove just the stylus assembly…remove it completely! You’ll want it out of the way, and you certainly don’t want to damage it.
  • Remove the counterweight and anti-skating weight.
  • Use a twist tie to secure the tonearm to the tonearm rest.
  • Remove the tonearm from the plinth. First, loosen the phono cable strain relief under the table, then free the cable from it. Using a 1/4″ socket, locate the two holes under the tonearm and, using a screwdriver from the top, loosen and remove the two screws. At this point, the tonearm will come free from the plinth.
  • With the tonearm out, locate two screws at the bottom of the tonearm post, where the cable exits from the bottom. You’ll find two small screws. Using a jeweler’s screwdrive, loosen both screws until you can pull the cable out of the bottom of the tonearm. Do it carefully, as you do not want to break off any of the wires.
  • Note the location of the wires and the terminals to which they are soldered. If you look at the terminals with all of them on the bottom (like a smiley face), from left to right, you have your red, green, ground, blue and white wires. The middle ground lead should have a thicker green wire, and a bare copper wire attached to it. The other four are your tonearm wires. Unsolder all of these wires from the terminals, and put the cable assembly aside.
  • From the cartridge end, pull the old wires out. When you do so, a small piece of foam should pop out with the wires. This foam is simply used to hold the wires in place.
  • With the old wires out, loosen your twist tie, and with the headshell end of the tonearm facing you, reposition the tonearm so it goes as far down in front, and to the right, as you can get it. This will raise the back of the tonearm sufficiently so you can work on the wiring easily.
  • Cut your “fishing” wire to more than twice the length of the tonearm.
  • Turn the tonearm around. From the back end, find the slot through with the wires entered the tonearm tube. Push your fishing wire through this slot, until it protrudes a couple of inches from the headshell end. Note that you are not fishing the wire up through the tonearm post–the corner is too sharp to fish wires through. You want a straight shot through the tonearm tube.
  • Prepare your four new wires for the tonearm–they should be more than twice as long as the tonearm. Or, about as long as the fishing wire you’re using. Strip one end of each wire about 1/2″ and twist the loose strands together.
  • Now, you will want to solder the ends of the wires to your fishing wire. This is where the braided picture hanging wire comes in handy–it will “wick” the solder and help the tonearm wires adhere to it. Now, what you want to do is solder one wire to the fishing wire about an inch or two away from where it enters the tonearm tube. For the next wire, solder it about an inch or so further down, so the solder joints do not overlap. Repeat for the third and fourth wire. You do this staggering so that you can more easily pull these through the slim opening.
  • From the headshell end, gently start pulling your fishing wire through the tube. Guide the wire into the slot or give it a gentle push, or move it around, so the fishing wire and tonearm wires all make it through the tube. If you’ve soldered well, you can tug a little harder. If you’re successful, all four wires will make it through unscathed.
  • Snip the wires off of the fishing wire. Pull the wire through so the arm is centered on it, and even up the ends. Tie a broad, loose knot in the end by the headshell, so that you can work on the other end without your wires slipping through.
  • On the back end of the tonearm, you will need to fish the wires through the slot so they come out of the bottom of the tonearm post. You may need the tweezers here, but you may be able to work them through one at a time by hand. Pull them all the way through.
  • From the tonearm post end, cut the wires just a little bit longer than the existing thick green grounding wire, and strip the ends about 1/4″. Using the color guide above, solder the wires to the posts. And remember to resolder the green and copper grounding wires to the center terminal.
  • From the headshell end, snip and strip the wires, so they extend to about the end of the headshell. You want ample length to easily attach the cartridge, but you also do not want to make them too long so that they hang down too far or look awkward. Eyeball it! Once you’re ready, solder the tonearm clips onto the wires.
  • Tuck the small piece of foam into the headshell end of the tonearm until it is just past the opening. This will secure the wires in place…not too tightly though, so be careful with the other end!
  • Loosen the twist tie, and move the tonearm through its entire path, making sure the wiring does not bind as you move the arm.
  • If the arm moves freely, then you can put the terminal piece back into the bottom of the tonearm post. Snug up the two screws, and again, move the arm to make sure it is not binding. If it is binding, you may need to remove the terminal piece again and try rearranging the wires. You do not want them to “bunch up” within the arm pivot area. The slot is sufficiently wide in the arm that the wires have room to move freely.
  • Using your multimeter, check for any shorts in your wiring. From the RCA plugs, check for no continuity between the shields and posts, and across the channels as well. (Make sure the cartridge clips are not touching each other!) Also, check each tonearm clip for continuity to the RCA plug. This will ensure your wires are not shorting, and that they are soldered properly.
  • Put the tonearm back on the plinth, mount the cartridge, and replace the anti-skating weight and the counterweight.
  • If all has gone well, hook it up and give it a spin!
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