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My Columbia no 8 soundbox has been fully rebuilt, new gaskets sealed the diaphragm screw with a bit of wax and cleaned and lubed the ball bearings.

Yet it is blasting and I have adjusted EVERYTHING, the pivots, how tight the diaphragm is clamed by the needle bar screw and the diaphragm isn't touching the metal in the soundbox I even trimmed the diaphragm about 0.5mm all around the edge to ensure it didn't touch the inside of the soundbox as it was very close to it.

HELP!!!

I've worked on several No. 9's, so can't speak to your particular problem with the No. 8, but imagine they are similar in construct. Have you determined if the needle bar is properly positioned between the pivot points on the soundbox? By that, I mean it can't be too loose or too tight, but just right, i.e., where if the needle bar were detached from the diaphragm and attached to the pivot points, that the bar would swing freely between them, but not such that it was loose. Improper tension there could create the blasting you're referring to. It's a trial-and-error type of adjustment, but perhaps worth a try. As well, in my experience, the Columbia soundboxes provided with the Viva-Tonals of this period tend to be very loud. I have found that using soft or half tone needles is more than sufficient with them.

I have tested the reproducer on other machines and there is no blasting i wonder if pot metal tone arm and horn could affect the sound? I have made plastic adapter and it plays perfectly on my 102 test machine.

Any thoughts?

12jslater wrote:I have tested the reproducer on other machines and there is no blasting i wonder if pot metal tone arm and horn could affect the sound? I have made plastic adapter and it plays perfectly on my 102 test machine.

Any thoughts?

Not the soundbox then !

is there a possibility the potmetal swelling has caused this?

Check that nothing is loose and rattling around in either the arm or the internal horn. I had the same problem, and blamed the soundbox, but it turned out to be a tiny bit of pot-metal that had flaked off, and was vibrating in the arm on loud passages.

12jslater wrote:is there a possibility the potmetal swelling has caused this?

Maybe. How loose are the joints in the tone arm? You just have to play detective and look at everything from the tip of the needle to the opening of the horn.

Here's another possibility. Like many of us, I have several phonographs in one room. When I play my Orthophonic, it causes the reproducer in the cylinder phonograph directly across from it, to rattle, pretty loudly too. I just lower the reproducer onto the record and it stops. Anything like that a possibility?

No its a portable Columbia 112 and im still looking for more suggestions, thanks

12jslater wrote:No its a portable Columbia 112 and im still looking for more suggestions, thanks

When you say, "blasting" do you mean rattling, buzzing, overly high-pitched, loud and garbled?

If the needle-bar allows side-play -- a slight shake or movement toward the set screws -- that will cause a buzzing sound on some louder notes.

If the tone is garbled or harsh, the diaphragm may be suspended too tightly in the gaskets. When you insert a needle, you should be able to feel the entire diaphragm plunge VERY slightly. The same is true if you insert a needle and flex it back and forth, GENTLY. If there is no detectable movement, there may be too much force exerted by the gaskets, and softer, or thinner gaskets may be needed.

Another thing to check out is whether the metal horn is dampened properly so it does not vibrate in sympathy with the music. Put a few layers of felt, or heavy fabric, under and on top of the horn to test.

HTH,
OF