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fran604g wrote: I realize now that the diaphragm string on mine is too long.

Fran

Are you sure?

Your reproducer is unrestored, and has the original linkage. I didn't notice any problem with it, but I'll be happy to take a look at it next time I'm over.

If your pin isn't centered in the limit loop, there are other adjustments to fix that - - I can show you.

George P.

phonogfp wrote:

fran604g wrote: I realize now that the diaphragm string on mine is too long.

Fran

Are you sure?

Your reproducer is unrestored, and has the original linkage. I didn't notice any problem with it, but I'll be happy to take a look at it next time I'm over.

If your pin isn't centered in the limit loop, there are other adjustments to fix that - - I can show you.

George P.

Thanks George,

I certainly would appreciate you taking a look next time you're here.

I'm glad you pointed that out. After reflecting a bit and reading through my copy of the Edison Laboratories, "Edison Disc Motor Manual", I realised that this was the wrong approach for me to take. I was putting the cart before the horse!

I was getting some skipping from the limit pin contacting the limit loop at the very bottom of the loop. I then commenced to adjust the reproducer height as instructed in the manual. The reproducer height needed to be lowered and the lift handle needed to be adjusted, too. A nice lesson in Diamond Disc motor design and operation!

She's all adjusted now, and plays nicely.

However, with the proper (as instructed) reproducer height adjustment; the limit pin centered in the limit loop as shown in figure 1, the stylus bar is not anywhere close to being parallel to the record surface when playing as outlined in the same manual. This leads me to believe that the string is actually too short to allow the rearward end of the stylus bar to "drop" far enough to allow it to be parallel. Instead, it is indeed parallel to the angled bosses on the weight that the stylus bar pivots on.

Fran

Fran,

I put up on one note to you about his before but it never showed up, I must have hit the wrong key or something.

Is the diaphragm a newer one using a string or thread type linkage? If the rear is up at an angle then most likely it is too short, that is what was going on in the OP's report.

Larry

larryh wrote:Fran,

I put up on one note to you about his before but it never showed up, I must have hit the wrong key or something.

Is the diaphragm a newer one using a string or thread type linkage? If the rear is up at an angle then most likely it is too short, that is what was going on in the OP's report.

Larry

No Larry, it's completely all original. The link appears to me to be a woven fibre of some sort. Almost looks like hair to me.

Thanks,
Fran

Just curious, you are looking at the top edge of the stylus bar? The lower edge will slope since is tapered to the back.. All those adjustments can be a bit tricky. I have found some original diaphragms that do have a shorter linkage than others, and sometimes as that manual mentions the diaphragms can be warped with age causing them to not level correctly. I noticed at Ralph's that the latter LP used a thinner weight which may have needed a shorter linkage, but not positive of that.

Larry

I advise anyone owning a 90-100 yr old piece of tiny, delicate string NOT to twist it for any reason.

Does anyone really believe that in all the years of Edison's men testing everything in thousands of ways, that they never twisted the link & listened for a difference, or that different "angles of attack" (a scary idea, given the delicacy of century-old records!) were never tested? Second-guessing Edison is not a great idea.

larryh wrote:Just curious, you are looking at the top edge of the stylus bar? The lower edge will slope since is tapered to the back.. All those adjustments can be a bit tricky. I have found some original diaphragms that do have a shorter linkage than others, and sometimes as that manual mentions the diaphragms can be warped with age causing them to not level correctly. I noticed at Ralph's that the latter LP used a thinner weight which may have needed a shorter linkage, but not positive of that.

Larry

Ahhh, yes, it is the bottom edge of the bar. Thank you, Larry for pointing this out.

Before too many people get the wrong idea, I am all about observing first. I have much to learn and I'm not going to go about messing with anything that is original and works. I will, however, do the best I can to understand as much as I can. The pointers that many share here at TMF are a great help. The more discussions we have on the myriad topics related to our hobby, and to some their livelihood, helps further us all, I think.

Fran

Hi all,
Have been lurking a bit; plus had a busy week last week. It's good to let these conversations develop without the initiator jumping in to comment at every point.

Edisone, I'm not at all bothered about twisting a 90-100 year old string as all my diaphragms are NEW (including Larry's spectacular design). Larry's strings are white, tough, and will bear many twisting and untwistings in the years ahead as I pursue the best sound. Do I accept that the Edison guys worked their problems countless times and figured things out as best as they could? Absolutely. But that doesn't mean I lose my right to make adjustments to suit my ear, in search of the sweet spot on any stylus.

Fran, don't worry about being a heretic for pursuing this matter. You're not. It's all a learning process and multiple points of view can be helpful--even if they are not always reconcilable. As Pontius Pilate said at one point, "What is truth?"

coyote wrote:Ralph,
I concur with your findings, if I am reading them correctly. While the needle bar in my reproducers are more or less horizontal when the limit pin is in the middle of the loop, I think the sound is better when the angle is a bit steeper, that is, maybe a pin diameter closer to the BOTTOM of the limit loop when in playing position. It also seems to me that different angle "sweet spots" are dependent on the particular diamond being used as well. The set-down levers in my machines have enough friction so that they will stay in almost any position off the vertical, so even though the horn height is set to be "correct" per the manual with the limit loop at the center when the lever is fully vertical, I find myself keeping the lever at some degree less than vertical, which slightly changes the stylus angle while still fully engaging the worm gear.

Coyote, I actually should have replied right away to this marvelous report of yours so that I can say that I concur in turn with YOUR findings. You have described yet another way that one can approach the "sweet spot" on one's Edison DD stylus: the set-down lever does allow for some variability while still fully engaging the worm gear; I was just experimenting with that a few minutes ago. Not only can one search for the "sweet spot," but one can also angle the stylus to best advantage in eliminating as much surface noise as possible.

Given all these ways that Edison DD styli can be adjusted re. "rake," why not?

Ralph

I have multiple Diamond Disc machines and have been playing them for 48 years, so I have a few opinions, right or wrong.

Assuming there is no wear to the diamond, the profile of the diamond is a cone with a perfect hemisphere tip. Therefore the angle of the stylus bar should not super critical to be within the "sweet spot" zone, and in my actual experience, it isn't. However, if the diamond is worn and has a flat spot, changing the angle can cause the facet's edge to cut the record. Changing gaskets will do that, as I discovered.

Ideally, 1) the stylus T bar should be parallel to the record, and 2) the weight limit pin should be centered within the loop when playing the average record. If those two conditions cannot both be met, then either the diaphragm has become cupped, or the interior gasket is too thick or thin, or the link has been replaced with something too short or long.

I have replaced broken links before with homemade replica links, right down to the brass end hooks made from scratch. It can take a lot of trial fitting to get the link's length just right.