The Talking Machine Forum — For All Antique Phonographs & Recordings

I recently purchased a C19 and it came with about 40 DDs. A little over half have some type of damage to them. I understand that deep scratches or chips would probably damage the stylus but what about light scratches or dimples in the surface? Does your finger nail have to catch in the scratch to cause problems? What about small dimples in the surface vs outright chips?

How fragile are these DD stylus? Some internet chatter sounds like any imperfections are cause for great concern. Mine is yet to come back from being rebuilt and I'm a bit paranoid now. Thoughts?

Hi Joe, I treat my DD reproducer similarly to my modern audio gear. If there is obvious damage to a record, I don't use it.

Perhaps I'm being over cautious, but a scratch diminishes the playback to some greater or lesser degree anyway. Personally, I don't find much enjoyment listening to a record and being aware (paranoid) that I could damage the stylus. It stinks, for sure, but I resist the temptation.

If it's audible, it's too damaged, IMHO.

Just my $0.02, YMMV.

Best,
Fran

Thanks.

Since these are hill and dale recordings how deep does the scratch/dimple/etc have to be to cause problems? Or are the grooves so shallow it doesn't really matter?

Honestly, there are too many variables to make a definitive statement. I would think that even the shape of a defect could determine damage. Sharp edges vs. smooth dimples, etc. This is such a subjective topic, I'm sure pages can be (and probably have been) written on it.

I'm sure you're aware that even dirt can cause eventual damage, from just normal wear and tear.

With vinyl, the "finger nail" test is how I determine whether or not I will play something (if you can feel it, it will be audible.) Obviously, Diamond Disc records are quite different and I don't know if anyone can predict how a particular minor defect will affect a diamond stylus.

I hope folks with much more experience (time playing records) will weigh in on the topic.

Best,
Fran

over the last decade or so i have digitized about 50,000+ recordings ranging from the 1890s to the 1950s
for this i amounted about 4000 sapphires of different mu's so if i want to digitize a record that might damage the good set i simply build my own
in my experience the real danger comes from cracked records the ruff bit on dd's doesn't seem to do too much damage to the needle indeed it rather seems to do more damage to the record since the material of the sapphire is far harder than the surface of the dd but then again i only play such a record once just for digital archiving playing such a record over and over would lead to some damage but i think you would have to play it hundreds of times before such damage would become evident i wouldn't worry to much about it because you probably won't play a record that much in a lifetime and certainly not with the same sapphire or diamond

digitizing the early vulcanized rubber berliner records is far more of a challenge to your stylus than a damaged dd can ever be the grooves are ruff and the material slightly warped i had a broken off sapphire on those once or twice and warped edison blue amberols are no walk in the park either i digitize those at low speeds

tino

I have been playing DD's for 48 years and have yet to damage a diamond. In my younger years, I foolishly played some heavily scratched records and even a few with tight radial cracks. It simply did not occur to me then that a "hard" diamond might shatter. It comes down to luck, I suppose. As I understand, diamonds have a grain, like wood. Strike a blow at the right angle, and a piece will flake off. In conclusion, I don't play heavily scratched records for fear of damaging an original diamond. Maybe when the new Bruce diamonds become available I could afford to be more reckless, but I simply try to avoid buying scratched or pitted records in the first place.

Diamond is the hardest substance known to man, but it is very brittle as well. Drill bits, a regular high speed steel drill bit will not remain sharp as long as a cobalt which is more brittle, the carbide bits are much harder than cobalt, but they are so brittle they will snap easily in the small #65 to #80 range that I use.

I spoke with Bruce diamond today. Edison started out with bare diamonds he silver plated and soldered in the bar. These broke easily with careless lowering. Edison then made a diamond assembly by plating the diamond in tongs with nickel which will plate under pressure. This nickel diamond assembly made his diamonds much stronger.

Bruce has gone two steps further, since they make scribers they will orient the diamond in relation with its grain and their diamond is smaller and held onto stainless steel via vacuum brazing. Since the diamond is smaller it will be stronger as there is less of the brittle material. Early Edison diamonds were large, the later ones were quite small in comparison and I have worked on 2 Edison diamonds that were loose and 2 that were in at an angle and not straight. The Edison diamond assemblies hugely vary in length, taper, and are not consistent at all when compared with the drawing. The total Edison diamond assembly height is supposed to be between .1543 and .1584 but that is not the case.

Always remember diamond is very hard, but also very brittle. At work the Apex bits we use to remove screws off the aircraft are very hard, but they are brittle as well. When using an impact Dewalt you will eventually fatigue the tip and it will break off in the screw unless you replace them regularly. Because the Apex is so hard even a cobalt drill bit will not remove the broken tip so a carbide grinder is necessary.

So the bottom line is that although Bruce diamonds are stronger because they have continued the evolution of technology Edison started, diamonds are still very brittle.

Please let me know if you have questions, remember I do not know it all and I am happy to learn which I did today. I am keenly aware that there are a huge multitude of people more knowledgeable that I and I never mind being corrected.

I started collecting various talking machines, gramophones, Diamond Disc machines at a very early age. My Edison DD Laboratory model Chippendale upright I have owned since I was about 11. (I'm 63 now) One time, not long after my father acquired it for me (for $20 I believe) I was winding it up, while playing a disc. I wound it up almost all the way, and the catch did not hold and I let go the crank and it spun violently, unwinding the spring creating a huge vibration as it did so. (It really scared me) The diamond needle cut several gouges in the disc while this happened. Interestingly enough, even though the disc was ruined (I've since acquired another copy of this disc), the stylus survived!! It still to this day, 40 years later plays Diamond Disc records without any damage to them whatsoever. Although this is not my best reproducer, it is interesting that it survived and plays equally to before the "accident".