Help Setting Up A Turntable: Marantz 6100

orthobiz · « **on:** 9 Apr 2009, 11:26 pm »

OK, so a few months ago I buy this Marantz from my local audio dealer. A used Marantz, decent condition, new stylus on the Grado, and the same guy who set up my Linn adjusts it. Finishing touches on the antiskate with a Shure record.

Now I'm getting more into the TT DIY thing, set up a Denon DD in place of the Marantz. As I look at this TT, I'm thinking the cartridge is wildly skewed. I go to VinylEngine and check out the owner's manual: You are supposed to use the 45 RPM adapter. Align the large arrow to point directly to the back of the unit and line up the stylus with the little crosshair dot marking on the adapter.

So, is the manufacturer right? Or is the setup jig my audio guru used wrong (I forgot what it was exactly, I believe a metal thing that fit on the spindle with an alignment dot)? Are the two screws in the slots on the headshell supposed to be equal so the cartridge is parallel to the headshell?

Pics:

I mean, is that stylus off, or what?

Paul

Wayner · « **Reply #1 on:** 10 Apr 2009, 11:25 am »

Paul,

Your arm is not made that far off. I think you should reset your cartridge so that the front of the cartridge is parallel with the front of the head shell. Then, bring the arm assembly to the 45 rpm adaptor with the pointer on the adaptor in-line with the spindle and the tonearm pivot center. Line the stylus up with the pointer, but still keeping the cartridge "square to the world". The arrow should be on the outside, pointing outward. Since the 45 RPM adaptor is 1.50" in diameter, that makes the overhang .75" (or half of the RPM diameter). This then makes me think that Marantz went with the classic 8.25" spindle to pivot center distance, adding on the overhang, makes for a standard 9.00" effective tonearm length (stylus to tonearm pivot center).

Wayner

orthobiz · « **Reply #2 on:** 10 Apr 2009, 11:51 am »

Thanks Otis and Wayner! I'll check it out and take new pics sometime this week. I'm taking the kids (14, 16, 19) to see Mates of State in Chicago this weekend, so no TT stuff going on (even though my VPI SDS is supposed to arrive today!!!).

My cartridge adjustment does raise a couple of questions:
1. Since my audio shop used a protractor, how is it possible that it could be so far off?
2. If it's that far off on my kids table, what about my Linn Sondek? I know he used all Rega dedicated setup stuff and that the armboard was predrilled by Linn for the Rega. As best I can tell, the spindle to Rega pivot is the 222mm it's supposed to be.

Wayner, if you have absolutely nothing else to do, I'd love a protractor for my Linn (and maybe even the Marantz). Maybe when you start doing tests with the metric version of your universal, I could be a test volunteer. After all, there is no better "untrained man on the street person chosen at random with no previous experience" than I!

Paul

Wayner · « **Reply #3 on:** 10 Apr 2009, 01:49 pm »

If your salesman dude set up 3 different makes/models of turntables with the same tool (a Rega), He knows not what he is doing.

Wayner

Wayner · « **Reply #4 on:** 10 Apr 2009, 01:54 pm »

Paul,

I made a little diagram on the white board. This should help you figure out how to set the cart up.

Wayner

orthobiz · « **Reply #5 on:** 10 Apr 2009, 08:09 pm »

The arrow IS supposed to point directly backward according to the vinylengine manual scan. Before I looked (the TT did not come with a manual), I had no idea what the hieroglyphs on the 45 rpm adapter were for. There is still a little subjectivity in setup, however, as subtle rotations of the platter and eyeballing the exact perpendicular point of the big arrow is not super accurate.

Paul

Wayner · « **Reply #6 on:** 10 Apr 2009, 08:26 pm »

That wouldn't make any sense, and I know the vinyl engine stuff isn't always right. If you are suppose to align the stylus to the arrow and it's between the spindle and the tonearm pivot center, that would be a -.75" overhang. That is why your stylus looks so f'd up in the picture. Trust me, I'm pretty sure the vinyl engine manual is wrong.

Prove it yourself. Take a ruler or tape measure and just eyeball the distance between the spindle center and the tonearm pivot center. If it's real close to 8 1/4", then the vinly engine manual is definitely wrong.

let me know......

Wayner

orthobiz · « **Reply #7 on:** 10 Apr 2009, 08:33 pm »

The vinylengine manual is a scan of the original. I'll check into it next week and will post pics when I do the deed. How would a custom protractor compare, Wayner? Or even one of the generic protractors, like the DB? Do I trust the manufacturer in general? Or did some of them make compromises that thirty years later go against current knowledge? I think I asked too many questions...

The arrow points to the back of the table, the alignment to the crosshairs.

Paul

Wayner · « **Reply #8 on:** 10 Apr 2009, 08:51 pm »

Perhaps it's a misinterpretation of the intent. I will find the specs and make you a card.

W

Wayner · « **Reply #9 on:** 10 Apr 2009, 08:53 pm »

I looked at the picture again. What is the little + sign for? Maybe the arrow is suppose to point at the pivot and you are suppose to align the stylus up with the + sign?

Wayner

Wayner · « **Reply #10 on:** 10 Apr 2009, 09:02 pm »

Ok Otis, If the pointer is suppose to point straight towards the back of the table, does that put the + sign in line with the spindle and the tonearm pivot center?

W

Wayner · « **Reply #11 on:** 10 Apr 2009, 09:06 pm »

And I looked again and it looks like it does!!!!!

Now the puzzel is getting clearer. You guys are suppose to align your stylus on the + thingy when the arrow is pointed straight back. That changes the overhang number so it's less than .75", which is OK. When you align your stylus on the + keep the front of the cartridge parallel with the front of the headshell. This will keep your offset angle in tow.

Wayner

Wayner · « **Reply #12 on:** 10 Apr 2009, 09:11 pm »

OK. It reminds me of the pointer that Acoustic research used to set the stylus. They had a plastic arrow, that you pointed at the tone arm and then a dimple to set the stylus in....very simple.

Wayner · « **Reply #13 on:** 10 Apr 2009, 09:17 pm »

Here is how AR did it:

Wayner

Wayner · « **Reply #14 on:** 10 Apr 2009, 09:19 pm »

Close up of the dimple:

W

Wayner · « **Reply #15 on:** 10 Apr 2009, 09:22 pm »

With an alignment jig like this, the error rate was extremely small because the stylus "dimple" was on the other side of the spindle, even gross errors at pointing at the tonearm pivot center still put the user in the ballpark.

Wayner

Wayner · « **Reply #16 on:** 10 Apr 2009, 09:44 pm »

I haven't run the numbers in awhile, and I ain't going to tonight. But will tomorrow. We've started the BBQ and interests are changing towards wonderful Cajin Chicken, Potatoes and Beets......

Wayner

orthobiz · « **Reply #17 on:** 11 Apr 2009, 12:14 am »

Some numbers on the 6100:
Effective length: 213mm
Overhang: 11mm

Paul