SL-1600 tonearm rewire

[kenwood61]

This is my first tonearm rewire, and I must admit, I was a bit nervous about taking this on. I think the main reason I was willing to do it was simply that it's not my main table. However, at the conclusion of the project, I will tell you that with a SAE 1000e cartridge mounted, this is almost as good as my AR XA with Rega RB250 tonearm (mod by Audio Origami) that Steve Frosten put together for me. That doesn't mean the AR is a slouch. It means that Technics made some really nice, somewhat under-appreciated tables. I'm telling you, I finished this project just after 1 AM last Saturday, and I stayed up another hour just trying to figure out which table was better. That is saying something!!

So on to the rewire. I have a ton of photos and won't post them all. But I do want to have a photo gallery showing the process well enough that it will hopefully encourage anyone trying to decide if this is something they want to take on. Part of the reason I think this is worth a post is that I was looking for helpful posts, but only found picture-related how-to's for newer models which have different base designs. So here goes . . .

Phase 1 - Remove the headshell and lock the tonearm in place. Remove the mat and platter. Unscrew the black metal coverplate for the motor. Remove pcb connectors. One is on the circuit board for the motor. The other, is to the large circuit board to the left. Now you are ready to unscrew the four feet underneath (which hold the tt together). Carefully hold the top plate so it doesn't fall away. Once you've done this, you can pull the turntable apart. However, now, you will need to unlatch the tonearm so it can move freely. As you pull the top plate off, you will see that you need to carefully maneuver it over and off without damaging the tonearm.

Here's what you should have.

Top plate - top



Top plate - underneath



Base - take pictures of the gearing. It's a good idea to note where the top plate controls are set to.





Here's a shot of where the Start/Stop lever connects with the main mechanism.

[kenwood61]

There are three black screws that hold the tonearm in place. Once you remove those, this is what you'll see underneath the tonearm base.





Notice the corkscrew-shaped wire that holds the tonearm wires away from moving parts.



Here's the tonearm pcb you will need to heat-up solder to remove the wires. I was able to reuse the existing solder. There is plenty, and it made the job easier.

[kenwood61]

Here is the pcb that the stock wires are soldered to. You don't need it. Remove and keep the screw. You'll need it later.

[kenwood61]

Flip the tonearm over so you can remove the two small screws that hold the bayonet in place.



Use a firm grip and take your time. Once removed you need to use some carefully moderated force to pull the bayonet out. I had to resort to a little sideways back and forth force to loosen.



Then cut those wires close to the bayonet. Leave enough length so the main wires won't go back inside the tonearm. Don't worry about the orientation. You can't put it back in wrong.



SPECIAL NOTE: You want to solder wires to the headshell BEFORE running through the tonearm so you know how much you have to "play" with.

Put an empty headshell back on the bayonet to act as a heat sink.



Pull the insulators off the cartridge pins and slip down on the new wires, away from where you'll solder. You want to reuse these. Or if they are in bad shape, get some 3/16" heat shrink so you can protect the solder points from each other. I have a pair of needle nose pliers that are round points and smooth, so I was able to pull from the end of the insulators without tearing them.

Solder one wire at a time. I was able to melt the end of the new wire about 1/8". Then heat up the solder on the tag, holding the wire close enough to slip into the molten solder. I had to do a little touchup to get the solder on each wire clean and smooth. Some of this was finished after I took photos.



All soldered.



Insulation back on.



Now you need to solder the end of the new wires to the old. Actually, you should try one to one wire. I tried the whole bunch and the connection broke twice. I figured that if I soldered to ONE wire and it didn't work, I'd have three more . . . more on that later.



It's "later" already, so here's what happened. After unsuccessfully trying twice, I just pulled the four main wires out. In this case, I left the stock ground wires in place. I took a piece of the stock external ground wire and soldered the new Cardas wire to it. Then I put some heat shrink on it.



I love this cool heat gun I bought at Fry's Electronics for $15. It has a nifty metal stand and switch. (I want to heat shrink more stuff, anything!!)

[kenwood61]

It took me about 5 minutes, but I finally got the ground wire fished through the tonearm pivot area so I could see the end inside the tonearm base. I used some suture (medical scissors) to grab the end and pull it through.

[kenwood61]

Try to match the length of the stock wires, which means you need to note how much slack was in there. In my case, I didn't think of that, so at this point, I used common sense and gave myself enough slack to not hamper tonearm movement, but not to get in the way of moving parts. Once done, cut and then solder wires to proper spots on the pcb. You will notice I have not yet run solder between the black ground wires (earth) and the Right channel ground.



Carefully wind the tonearm wires into the corkscrew-shaped holder.

[kenwood61]

Now solder new phono leads direct to this pcb. This shows where I replaced the solder from the black ground wires (earth) to the Right channel ground. I cleaned up a bit more after taking this shot, so it looks better. I used a tie strap to secure the phono leads to the pcb using the small hole the stock wire ran through. This worked perfectly.



Now it's time to check the gearing inside the table base to make sure you haven't moved anything. Presumably, you set this aside so that you didn't move anything.

Carefully put the tonearm base back on. You'll want to bend the phono leads so they go around the back side of the back post that you screw the tonearm into. Make sure your tonearm wires are not getting caught up in any moving parts. This is when you realize how nice that corkscrew wire holder is.

[kenwood61]

After getting the tonearm in place and secure, run the phono leads to the slot where the stock wires entered the deck. You will NOT be able to reuse the black plastic holder that screwed into the top plate. That would force the phono leads to bend too much. See the metal rubber-coated tiedown to run the phono leads through to hold secure.

[kenwood61]

Audio Origami built my phono leads using Cardas wire and Neutrik rca jacks that were modified slightly. The ground wire with twisted end for the tonearm pcb board and chassis lead came with it.

Remember the screw I told you to save after removing the stock pcb board on the top plate? Well, you will now put that screw in to connect the chassis ground to.
Here it is again.








At this point, you simply reassemble the deck in reverse steps. Pay attention to keep the new phono leads in the stock location going out of the deck base. Pretty simple at this point.

[kenwood61]

Once you get the phono leads out and the deck back together, it should look something like this.

[kenwood61]

Finished and spinning vinyl again!!

[kenwood61]

This is a pesky little booger. The arm lift for the tonearm. I actually waited and messed with this today (a week later).

You have to remove this screw.



And then carefully maneuver the whole arm assembly out of place.

You can see here where I unsuccessfully tried to get silicone fluid down the post. Today I found out this is NOT where you put fluid. Nothing is underneath.

[kenwood61]

At this point, I didn't take pictures, but I can tell you what I did. I removed the plate underneath. Yes, I had to take the table apart again, and remove the tonearm to do this. So you really have to want to do it. My goad was to dampen the rate the arm lift dropped. So I had to remove the plate from the underside. Simple, just two screws. Got that out, then pulled the machined brass post that has grooves made to hold silicone. Cleaned it off the 99% iso alcohol, dried then put the silicone in the grooves and post back in place, reassemble and done. It works better, but not much. It's no big deal for me so I'll leave it alone.

When I get some more spending money, I plan to get some SoundCoat damping material (in sheets) from Parts Connexion. I really like that stuff. It's thin and does a really good job. I used it in my NAD c521i project and it made a difference.

The next major project is to build a wood base out of exotic wood. I am mulling over a few designs and will hopefully buy material in two weeks. Fortunately we have a great wood shop in Seattle called Crosscut Hardwoods. I'll be looking at some exotic woods from either Africa or South America that are workable for this project. For those of you that don't know, some hard woods are not easy to cut and not intended for furniture or cabinet making, but more for turning on a lathe for small projects.

As I get deeper into that project, I'll hopefully land on a solution I like for adjustable feet.

If I'm still loving this deck when that is done, I'll order another dustcover from JMK Display and this project will be complete.

[gridleakrick]

Great tutorial. Excellent pictures and descriptive text. We need more of these kinds of things. Come on folks. Break out those digital cameras and document your latest turntable projects for us all to see.
Rick