FOLLOW THE RESTORATION: brass Edison Needle Type reproducer

[MicaMonster]

Much like the Victrola #2 reproducer, the Edison Needle Type (NTP) reproducer is VERY VERY VERY under-rated, primarily because it is often repaired incorrectly. This specific reproducer would not only make a perfect replacement on the Needle Type Portable (NTP), P1 or P2 portable, but alone by itself it is very Art Deco. The reproducer is VERY well made, with lots of plates and screws, and gasketry. The one part which everyone misses when repairing is the mounting flange....which was originally very soft latex rubber. It isolates the vibration of the reproducer from the tone arm, and also eliminates reflexive feedback to the needle which increases record wear and strident tones. These NTP reproducers are absolute monsters of sound.

This reproducer had an enlarged hole in the center of the diaphragm, so I cut a small piece of duralumin, formed it to the curve of the diaphragm cup, and bonded it into position with a very strong but lightweight adhesive (cyanoacrylate), a permanent repair. The needle bar is bearing suspended, much like a Viva Tonal, with ball bearings on cone screws. The allloy diaphragm is suspended with soft rubber (now butyl rubber) gaskets. Whenever I install gaskets, I install with GENTLE clamping pressure, to allow for a good seal, but to also allow the diaphragm to move with low frequencies. TOO MUCH PRESSURE STRANGLES THE ABILITY FOR THE DIAPHRAGM TO WORK.

The mounting flange gasket, I have replaced with silicone (GE Silicone II). In the excitement of the work, I failed to take a picture of the application of silicone. I spread two circular paths onto the back plate. One around the center hole, and another midway between the center hole and the outer edge. I then sandwiched it together, using three pieces of card stock as a spacer to allow a proper gap to keep the vibrations isolated. After the silicone cures, we will have a perfect isolator!

The three shoulder screws that hold the back flange onto the body also had rubber washers and insulators...all which have turned rock hard from age. I cut some surgical latex tubing for each screw to isolate them from the flange. Tonight the silicone will cure. Tomorrow I'll remove the cardstock shims.

And that's how it's done!

[Oceangoer1]

I am so excited to see this process! I would love to see a video demonstrating how it sounds once it is fully rebuilt.

I have this same reproducer (and the portable to match). The design looks similar to the Columbia Viva Tonal reproducer. Keep the updates coming!

-Connor

[MicaMonster]

Alright Mr. DeMille, I'm ready for my closeup! Sound fabulous, but I don't have a machine to put it on.

[Lucius1958]

I wonder how that would compare to the Prime reproducer on my P-1? Much better, I should think.

Bill

[MicaMonster]

I wonder how that would compare to the Prime reproducer on my P-1? Much better, I should think.

Bill

The pot metal reproducers on the P-1 and P-2 sound HUGE. As I recall, the difference is in the pivot of the needle bar. The NTP reproducer uses bearings, whereas the pot metal reproducers use a thin piece of spring steel held to the body with two screws. I've found that sometimes when the pot metal bodies swell slightly, you will need to loosen the screws and back the needle bar away from its mounting block, because sometimes the bar touches the block, muting the sound transmission.

[fran604g]

Some very fine work there, Wyatt! This is a wonderful post, thank you for finding the time to show us how it's done.

Best,
Fran

[Victrolacollector]

I have been on the lookout for one of these as an adapter for my Edison machine to play regular 78's. Thank you for sharing with us. Looks like you are doing a good restoration and I am sure that the results will be great.

[MicaMonster]

This will be in the Yankee Trader soon.....