Tuning up an Akai AP-206 turntable-overhang adjustment

jimbo1421

Hello,

I am trying to set the overhang on my turntable following the directions in the manual (see attachment). They don't work. The drawing shows the tone arm swung all the way to the center of the platter and aligning the stylus with a concentric indicator groove molded into the rubber mat. The trouble is I cannot move the tone arm that far to the center. I encounter resistance (not a hard stop) about an inch from the center. Do I dare force the tone arm any further?

My work around was this:
I marked the center of the pivot on top as best I could and used a pair of dividers to get the distance. I then moved the divider end to the top of the headshell and marked that spot. I then made pencil marks on the side of the cartridge, eyeballing my way around to the bottom. There are three pairs of screw holes 1/8" apart for the mounting screws (no slots) and I saw that the stylus aligned best with the pair that are farthest from the pivot. I think, as best I can tell by eye and my multistep measuring scheme, that I have the stylus within 1/16" of the where it should be. But I must admit that the whole method is pretty shaky. Does anyone have a better method?

Thanks,
Jim

jimmydep

Hi Jimbo,
I'm glad your getting into vinyl, I think it as a different sound from CD's, and the pops and hissing brings back memories.

You might try rotating the platter to see if you can get the arm to move to the center.

Jimmy

jimmydep

BTW, don't force it!!!

hearingimpared

Try this; http://www.elusivedisc.com/products.asp?dept=931 It's an old tried and true method.

jimbo1421

jimmydep wrote: »

Hi Jimbo,
I'm glad your getting into vinyl, I think it as a different sound from CD's, and the pops and hissing brings back memories.

You might try rotating the platter to see if you can get the arm to move to the center.

Jimmy

Thanks, Jimmy. I never got out of vinyl, but I had let SQ slip a lot in the last decade. Thanks to this forum I am developing audiophile tastes on a Craigslist budget.

Rotating the platter doesn't reveal an opening to center the headshell on the spindle. And no, I won't force it to go there.

Jim

jimbo1421

hearingimpared wrote: »

Try this; http://www.elusivedisc.com/products.asp?dept=931 It's an old tried and true method.

Thanks HI. I will check this out.

Jim

hearingimpared

jimbo1421 wrote: »

Thanks HI. I will check this out.

Jim

You may find it less expensive on another site.

jimbo1421

jimmydep wrote: »

BTW, don't force it!!!

I decided that the manufacturer's instructions had to be right so, taking my heart in my mouth, I gently pressed the tone arm to the spindle center. It sprung back and showed no apparent ill effects so I went ahead and set the overhang as instructed. Then I used the Stupid Protractor from http://www.vinylengine.com/cartridge-alignment-protractors.shtml to set the cartridge alignment. Following those instructions to the letter I got the Baerwald points aligned just right. This involved sliding the cartridge outwards about 2mm. Now the overhang is 17mm instead of 15mm that Akai specifies. After some more studying at Vinyl Engine's forums I could only conclude that this added overhang doesn't matter since I am using the Baerwald protractor's optimum settings and not Akai's. It does not seem possible to have both the Akai overhang and match the Baerwald null points at the same time. It seems to be just a matter of whose optimum I prefer. I may try setting it to the Akai setting, but for now it sounds better than it ever did.

I hope I did all this right. If so then I am on to the next tune up topic, setting the stylus pressure and anti-skate. But that will be another thread.

Jim

Andrei

Hello Jim! I'm quite new to the vinyl world. I have an Akai AP 206 as well, and I'm trying to adjust the overhang based on the page in the manual you posted. However, there is something I don’t understand. The image in the manual shows two circles surrounding the spindle, but the rubber pad (which is the original one) on my turntable shows three circles: a small one around the spindle, a second one and a third one, which is like a "boundary" circle. Now, my stylus is aligned exactly with this third boundary circle, with the boundary line. I really wonder which is the right circle to align the stylus with, as I got the feeling that my stylus is not on the right one, although the sound is really great… Thank you very much. Oh, and what is the stylus weight you use. Mine is 1,25. Is this correct? Thanks again.

jimbo1421

Andrei wrote: »

Hello Jim! I'm quite new to the vinyl world. I have an Akai AP 206 as well, and I'm trying to adjust the overhang based on the page in the manual you posted. However, there is something I don’t understand. The image in the manual shows two circles surrounding the spindle, but the rubber pad (which is the original one) on my turntable shows three circles: a small one around the spindle, a second one and a third one, which is like a "boundary" circle. Now, my stylus is aligned exactly with this third boundary circle, with the boundary line. I really wonder which is the right circle to align the stylus with, as I got the feeling that my stylus is not on the right one, although the sound is really great… Thank you very much. Oh, and what is the stylus weight you use. Mine is 1,25. Is this correct? Thanks again.

Hi Andrei, and welcome to Club Polk in the wee small hours. Elsewhere in my manual, the overhang is specified at 15mm. So whichever circle has that radius is the right one according to Akai. However, as I said above, I used the Baerwald points on the Stupid Protractor from http://www.vinylengine.com/cartridge-alignment-protractors.shtml. This resulted in an overhang of 17mm. Either one could be "right", just whatever sounds best. Geometrically, there are one, or at most, two points on the path of the stylus across the record where the long axis of an elliptical stylus is exactly aligned perpendicular to the groove, which is the way the record was cut originally. Which two points are best is a matter of debate. Since this was the first time I used a protractor, I chose the easiest.

My stylus weight is specified at 3/4 to 1-3/4 grams. I ended up near the high end at 1.7 grams as measured on the tone arm counterbalance (I don't have a stylus gauge). Others have also recommended the heavier weight to keep the stylus from skittering over the more complex wave forms. So look up your cartridge specs, start in the middle of the range and work up from there, without going over the maximum. I am still not sure that I have the optimum anti-skate setting; I am still playing with it.

There is lots more good info at Vinyl Engine.

Jim

SCompRacer

jimbo1421 wrote: »

I may try setting it to the Akai setting, but for now it sounds better than it ever did.

I hope I did all this right.

Jim, also from the Engine (if you didn't see it):

Which is the best?
I won’t tell you there is one better than the others. Make your own opinion.


Simply, the equation you need to solve to find optimal alignment is undetermined: there are too many unknown parameters. Baerwald, Loefgren and Stevenson apply different objective constraints to the problem to allow a solution:

Baerwald The distortion at the beginning, the middle (where it’s high) and the end of the record must be equal

Loefgren Alignment must minimize the distortion across the record

Stevenson Distortion is more important at the end of the record so let’s minimize it by assuming a null point at the end of the record, i.e. at 60.325 mm (IEC standard end of the record)

So there you go. Whatever works best for you.

Andrei

Hey Jim, thanks for answering. Seems that I just have to experiment a little more with my turntable. I am so happy with it. For now, I just had the overhang set at 15 mm, and the stylus weight at 1,5. The sound seems to be a little cleaner..
I would have another question: what type of cartridge / stylus do you use with yours? I have no clue what cartridge I have, the guy that I bought the TT from didn't know either...I'm willing to experiment with it, and change the cartridge / stylus to see if I could get even better results. Thanks.

jimbo1421

Good Morning Andrei. 1.5 grams seems like a good guess, but I believe you should at least replace the stylus, unless the seller persuasively assured you that the stylus was pretty new. If the make is not visible, you will need to remove the cartridge from the headshell. The make and model are usually printed on the top. With that information you can look up the stylus weight at http://www.cartridgedb.com/. You can order replacement styli from http://www.jukemania.com/ or http://www.needledoctor.com/. Avoid stereoneedles.com. It took them two months to replace a defective stylus they sold me.

My AP-206 was a freebie and came with an Audio-Technica AT14Sa cartridge, which is long out of production. Since I have been paying more attention to the speaker end of my system I haven't looked for a new one. I have heard good things about one of the Shure models, but can't remember the model. You can search CP to find it.

You should check the azimuth to make sure it is perpendicular to the record surface. Get a small mirror and with the turntable off, gently set the stylus on the mirror. When viewed from the front, the cantilever should line up with its reflection.

Enjoy your records,

Jim

hearingimpared

jimbo1421 wrote: »

You should check the azimuth to make sure it is perpendicular to the record surface. Get a small mirror and with the turntable off, gently set the stylus on the mirror. When viewed from the front, the cantilever should line up with its reflection.
Enjoy your records,

Jim

I think you mean the stylus here. The stylus should line up with its reflection. Don't use the cantilever tube as a guide as it could be slightly rotated and the stylus would not be perpendicular to the record.

jimbo1421

hearingimpared wrote: »

I think you mean the stylus here. The stylus should line up with its reflection. Don't use the cantilever tube as a guide as it could be slightly rotated and the stylus would not be perpendicular to the record.

Hello HI,

Well, yes, but viewing the stylus with the naked eye, or even with a magnifying glass, is hard to do with the cartridge and headshell mounted. My vision certainly isn't good enough. I have attached a PDF illustrating some of the possible misalignments. #1 & #2 show what one should see. #3 shows the cantilever rotated about the Z axis at the rubber bushing. But since the bushing is above the record surface there would also be some component of rotation about the Y axis as well, as shown in #4. #5 shows my recent experience with a replacement stylus. The cantilever was both rotated and twisted in the bushing.

In situation #3 you could shift your eyeball as shown, but this is even harder than getting #2 right. I would suggest that if the stylus, cantilever, bushing and shell assembly are not properly aligned when it is snapped onto the cartridge body and viewed with a 10X hand lens, then a new replacement is in order.

Regards,
Jim

PS: I am open to revising the drawing to better show these relationships.

hearingimpared

Nice drawing. If the cantilever is such in block 3 then the zenith is off and will screw up the whole works. I use a magnifying glass (I forget what power) to line up the stylus with its reflection.

jimbo1421

hearingimpared wrote: »

I think you mean the stylus here. The stylus should line up with its reflection. Don't use the cantilever tube as a guide as it could be slightly rotated and the stylus would not be perpendicular to the record.

Here is another drawing where the cantilever is vertical, but the flattened part where the stylus is mounted is twisted. Is this what you mean by rotated? I would consider any of these situations a manufacturing defect, or damaged in use and replace the stylus. But I have never examined a stylus this closely until recently and maybe such precision isn't possible for $80-100.

Jim

hearingimpared

jimbo1421 wrote: »

Here is another drawing where the cantilever is vertical, but the flattened part where the stylus is mounted is twisted. Is this what you mean by rotated? I would consider any of these situations a manufacturing defect, or damaged in use and replace the stylus. But I have never examined a stylus this closely until recently and maybe such precision isn't possible for $80-100.

Jim

Yes, going by that drawing I would say there is a defect. However when mounting a cartridge if the two screws (most cases) are not torqued down equally you would get the same stylus appearance in the mirror thus the azimuth would be off and you would need to make sure both screws are tightened equally.

jimbo1421

So if the stylus, cantilever, shell and cartridge are all aligned properly, then one should be able to use the cantilever and its reflection to eyeball it for perpendicularity, not so? Then one can either adjust the cartridge in the headshell, or rotate the entire headshell assembly if that is possible (my headshell doesn't have that adjustment).

Regards,
Jim

Andrei

I tried to take some pictures of my cartridge as it is right now...
Jim, if by looking at these pictures you can figure out something, especially something that is not right, please let me know. Thank you. I tried the mirror azimuth alignment, but it looks right to me...
I tried to find something about the cartridge that I have, but couldn't find anything, nothing with those symbols on it, and I wouldnt venture right now to remove it...

jimbo1421

If you look at the drawings I posted, they show some of the ways a stylus can be misaligned. I use a 16x hand lens to examine mine.

I don't see anything wrong in the pics, but maybe someone else will.

Jim

hearingimpared

Andrei wrote: »

I tried to take some pictures of my cartridge as it is right now...
Jim, if by looking at these pictures you can figure out something, especially something that is not right, please let me know. Thank you. I tried the mirror azimuth alignment, but it looks right to me...
I tried to find something about the cartridge that I have, but couldn't find anything, nothing with those symbols on it, and I wouldnt venture right now to remove it...

It's hard to tell by the pics but it looks okay. Perhaps if you could take a picture of the cartridge head-on we could tell better.

Andrei

I'll try to take a few more pictures. I must say that I noticed a slight sound degradation towards the end of the LP, which leads me to the conclusion that something is not exactly right...What do you guys think that is the first thing I should check?
I tried to search the net for a compatible cartridge (as I said before I don't know what type of cartridge I have right now, nor if it is a new one. The guy that I bought the TT from said that he had the TT from somebody else and he only knew that the cartridge is not the original one).
Searching the net I found that the original cartridge is Akai RS-100. Another compatible cartridge seems to be the one Jim is using, but they're both out of production...
Anyway, considering that at the first songs the TT sounds absolutely amazing and only towards the end the sound seems to somewhat degrade, I would assume that it is not the cartridge, rather some alignment...or am I wrong?

hearingimpared

It could be the anti-skating is slightly off or the cartridge has not been properly aligned at the two null points.

A second thought here . . . does this happen on all LPs or just one?

Andrei

It happens on all LPs. And I can notice it only if I listen to it carefully, but it's definitely there.
There is something odd with the anti-skating though. When I bought the TT it was set at 1. While experimenting with the TT I set it at 2, but it came back, by itself, at something like 1.2 or 1.3, anyway right after 1 !! I just tried to set it again at 2, and it keeps coming back slowly to 1 while playing the LP...
By the way, very close to the stand I have the TT on, there is a subwoofer. Could this affect in any way the sound?

hearingimpared

Andrei wrote: »

By the way, very close to the stand I have the TT on, there is a subwoofer. Could this affect in any way the sound?

Absolutely! You need to isolate the turntable from the stand. I use Black Diamond Racing Cones and Isol-pads from Quest for Sound.

If you tell Steve at Quest for Sound you are a member of Club Polk he'll give you a discount.

BTW make sure your platter is perfectly level.