So I picked up one Svelte (with a capital S!) looking turntable a little while back: the Marantz 6100. It had been up on Craigslist for quite some time and I had been eyeing it up, especially since it would match my Marantz amp I like so much. Finally I pulled the trigger. Immediately when I got it home I started noticing a series of issues. This post chronicles all that I’ve done to upgrade and fix it, for anyone who should want to do the same to theirs.
First thing wrong with it was that only one channel worked. Yikes, that’s a showstopper! Step one was to diagnose: swap the L/R channels as they were connected to my amp to make sure it was the turntable at fault and not the amplifier. It was the turntable. I took the bottom off and used the “beep”/continuity test setting on my multimeter to see where the signal was getting lost. Note that on older turntables like this, with no internal pre-amps, the four connecting pins off your turntable needle/cartridge are, electrically, connected directly to your receiver/amplifier. That means if you’re missing a channel, it’s a continuity problem: The guts of the turntable are simply wires.
First, I checked the continuity between the connections right at the needle and the solder joints on the inside of the deck. All beeped, so they’re good. Then I checked the solder connections to the end of the RCA ring/tip connectors. Sure enough, one was bad! I was surprised that old RCA jacks would actually fail like that. Hmph. I took a spare RCA cable, and cut off one end. Then I stripped the wires, revealing four different wire paths. I unsoldered the old one and soldered in the new one, making sure to leave a stress-relief knot, so the cable couldn’t be yanked out by accident.
Second thing I noticed was that the speed of this turntable is slightly slow. I searched around online and found that this is a well-chronicled issue with the model 6100 turntable. It’s driven by an AC motor, so a simple adjustment of the input voltage to the motor won’t remedy this issue. Somewhere online in a forum I saw someone recommend getting a slightly shorter belt. I called a few hi-fi stores and came to the conclusion that 25″ belts are common but 24.9″ belts, in fact, do not exist.
Then I got the idea of adding something to make the motor shaft very slightly larger in diameter, since that would effectively make it turn the belt faster. Scotch tape, maybe?? Sure enough, it works! At first I added two layers of tape and now my speed went from like 5% slow to like 5% too fast–a thin layer sure goes a long way. I took off one layer of the scotch tape so now it’s just a single loop around the motor shaft. With only one loop, now the turntable runs very, very slightly fast; maybe like 1-2% faster than normal. It’s the kind of thing where, if you’re listening hard for it, you could pick it out with effort, but if you sat down not knowing that the table was ever so slightly fast, you’d probably never notice.
At first I wondered if it would annoy me (5% too slow DEFINITELY annoyed me!) but after listening to a whole bunch of albums, I think I actually enjoy everything sped up by an almost imperceptible amount. It’s not enough to affect the pitch of familiar records; or if it is, being slightly sharp is less offensive to my ear than being flat. It does add a subtle extra ‘kick’ or energy, having that increase in tempo–an extra bpm or two. I’m digging it!
Lastly, I was getting distortion in the sound, like the signal was being overdriven or something. I figured since the turntable is nothing more than wires and mechanical support for the stylus, it was probably the stylus. Spoiler alert: it was. The old stylus was a Pickering VX-15 with a dust brush on the front. That dust brush seems like a great idea in theory, but it sort of sucks in reality: seems like it makes the record skip more, and you need lots more tracking force to prevent that. I’m not sure how old that needle was, but from the looks of it… OLD.
The Pickering was swapped out with a Grado “Green 1″ cartridge. Ka-BAM! This baby breathed a whole new life into the 6100. The anti-skate weight was missing from my deck, so I improvised with a couple zinc washers and some thread. I kept getting skips at the very start of every record, even when I had a lot of tracking force on the arm. Adding the anti-skate weight got rid of those skips at the beginning and allowed me to dial back the amount of tracking force needed. It’s still probably too much right now, but it is nice not getting any skips at all even on records which have known spots prone to it. I’ll keep dialing it back in the weeks to come.
The 6100 has two simple but nice features that I’ve enjoyed: auto-return and auto-shutdown, and buttons to toggle between 33/45 rpm. My other deck, the venerable Pro-Ject Debut III doesn’t have either of these. Auto return/shutdown means that you don’t have to worry about accidentally letting the turntable skip on the last groove all night because you forgot to shut it off, which I’ve totally done. The 33/45 buttons are a very basic feature the Pro-Ject lacks–you actually have to remove the platter and move the belt by hand, which gets old. Maybe that sounds lazy, but you end up yanking on the spindle too much to get the platter off, and I worry about long-term wear that might be causing. It just makes me nervous doing it, so I listened to less 45s on that deck. No longer!
But oh man, this Grado Green cartridge is awesome. The Pro-Ject Debut III has an Ortofon OM 5E cartridge, and that turntable sounds excellent. For the Marantz, I wanted to get a different brand, for the sake of sonic variety. Since I love my Grado headphones, it was a logical choice to try out their cartridge line. I’d describe the Ortofon as the “cleaner” of the two, and the Grado as the “warmer” of the two. That said, it’s not a jaw-dropping difference between them.
I hooked up the headphone extension cable and put on my Grado SR-225 headphones for a long listening session this last weekend… now that was really enjoyable!! Laying on the carpet with my eyes closed, blasting familiar recordings and oh yes, hearing a bunch of new details within them, thanks to yet another different listening setup. It’s chicken soup for the soul, just doing nothing but soaking in the awesome sounds of your favorite albums. After the soldering, reassembly, and tweaking this is the reward; not critical listening but blissful listening. I’m going to make it a point to just hang out and listen to records over the next few weeks, reaquainting myself with the collection again and enjoying the tunes. That’s what it’s all about!