alang
One Spring Motor
Posts: 43
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Post by alang on Nov 13, 2009 12:26:07 GMT -6
I am new to this forum and relatively new to the hobby. I have several lateral disk machines (Grafonola, Victrola, HMV), but recently my wife brought home an Edison Diamond Disk machine (BC34) from an auction. The technical and cosmetic clean up etc was no problem, it runs and looks great now, but the disks still sound terrible. I'm going to replace the gaskets and maybe the diaphragm in the reproducer next, but I am struggling with how to identify if the diamond in the stylus is good or not. With a magnifying glass I can see that there seems to be a diamond there, at least a pointed tip like I see in pictures on different web sites. But there are also horror stories around about cracked diamond tips etc. So can anyone advise how to tell if the diamond is good or bad? Or could it just be that all my 20 or so Diamond Disks are bad? None of my regular shellacks sound that terrible. It is not a very valuable machine, so I don't want to invest lots of money. I prefer "do it yourself". Any help is highly appreciated.
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Post by barnettrp21122 on Nov 18, 2009 23:56:22 GMT -6
The quickest way to determine if the diamond point may be damaging the grooves is to play a disc in the inside "run-off" blank area. If you observe the stylus making a definite fine groove of its own then there's a good chance the tip is blunted or rough. I use a lighted magnifier I bought at Radio Shack awhile back that helps better determine stylus condition. The best tips will look nicely rounded and shiny. You might get by with some "shouldering" of the sides of the stylus, but not for very long. Replacement stylii are available through various parts dealers, and I believe most if not all are supplied from Expert Stylus in England. You can expect to pay at least a hundred dollars nowadays for a new replacement. Quality control has been an issue in the past, and some collectors prefer picking up used reproducers on Ebay, hoping to find good used stylii to swap out. Nearly every Edison reproducer will benefit from a good rebuild. I would recommend not discarding the original diaphragm for modern material until you have first replaced just the gaskets. Beyond the need for the diaphragm to be airtight I feel there are others that could give better recommendations for adjusting the tightness of the gasket ring, etc., for best sound. Finally, Edison records are notorious for varying suface and pressing quality. The etched-label variety of the World War I era can look new and still have an objectionable amount of surface noise. It's generally accepted that the very first etched discs and later paper label discs were of better overall quality, though still not always consistent. Don't play any discs that have damaged surfaces or warped or swollen inner cores. You'll risk real damage to the diamond point. I hope this helps! Bob
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Dan G
Two Spring Motor
Posts: 55
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Post by Dan G on Dec 2, 2009 19:34:17 GMT -6
Get a small hand-held microscope from Radio Shack (dig through their catalogue). You can examine the point of the diamond stylus very easily at as low as 50x power.
What you need to look for are chips and sharp edges on the point of the stylus. The stylus itself can be obviously worn but still not damage the records, per se, unless the tip has a flatted area from wear - in which case you examine the stylus from head-on to look for sharp edges and chips. The 'dead wax' check is a good test, but the hardness of Diamond Disc surfaces varies to the point that you might not get a needle score on one particular record, but might get one on another particular record.
If you buy a new stylus, try to get a new diamond mounted in an original bar as the new bars have different specs on the length of the diaphragm end of the lever.
Also - check to see if the needle arm moves freely on the pivot pin and that the lateral motion of the hinge-block is good. And also check to see if the leaf spring on the hinge-block isn't fatigued or cracked.
Gaskets aren't that critical in the compliance department but a warped diaphragm can cause even a perfect stylus to cut a record to shreds if it causes the mechanical compliance to be too stiff or too soft. Too stiff and you chew the record grooves and too loose and you have a 'hopping stylus' that eats the peaks of the grooves and the faces of the upwards sides of the groove undulations.
Edison phonographs and records are extremely tolerant variations in specs despite some claims (they were designed to be so). If something is really wrong and you are minimally observant, you will notice it with flashing lights and red flags. But wear does occur and it's just a matter of knowing what is normal and what isn't.
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alang
One Spring Motor
Posts: 43
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Post by alang on Dec 21, 2009 15:48:40 GMT -6
Gentlemen, thank you very much for your detailed advice. I was away for business the last few weeks, but hope to find some time over the holidays to try your suggestions. Happy Holidays to all Andreas
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