Phono cartridge wiring to do it all...?

Fran604g

Just Call Me Junior
Hey folks,

I use a variety of devices to listen to audio, from 2 and 4 minute cylinder record phonographs and early to late lateral cut records, to Edison and Pathé vertical cut records, to modern stereo LPs, etcetera. But my capabilities to combine the old with the new(ish) technologies are limited in regard to playing both lateral and vertical cut records on a modern turntable using any one of my stereo systems.

Currently I use 3 stereo systems; my 2 main systems each use a DUAL 12xx series TT, and have the capability for switching to "mono", but that doesn't help me with playing vertical cut records without rewiring one channel of the stereo cartridge to be out of phase in regard to the other. Hence, I have several headshells set up with single purpose cartridge and stylus combinations to swap as needed, but when it comes to using them, I still desire more possibilities between what I have, and what I'd like to do.

The remaining 3rd system I put together is for playing mostly 78s, it is also stereo using a Miracord 10H (with the automatic guts removed - manual on/off), setup with a Pickering U38 cartridge and 2 different stylii options - one is 3 mil, and the other .7 mil. This way, if I choose, I can play LPs (in stereo), and lateral cut 78s (through both channels) without too much difficulty, and too much fusing around. Sometimes it even sounds pretty decent. ;) However, when I'd like to play my Edison or Pathé vertical cut records, I would need to either rewire the cartridge (I don't), or combine both channels from the cartridge (Y-stylee), and use my power amp bridged for mono (I do) playing through a single speaker. I've elected to not buy another head shell and cartridge to rewire for vertical use only - I just don't use it enough to rationalize the expense, even though it might not be much $$$.

I'm familiar with many of the "how-to's" we've all probably seen for playing 78s using modernish equipment, but instead I want to try something else just for fun that makes sense to me; I found it in an old publication called The Antique Phonograph Monthly, featured in the Aug.-Sept., 1975 issue.

Another switch adds more fun! 🥳

I wonder if anyone here has ever built and used something similar? Problem is that I'm not sure how well it might perform without creating hum, or other signal issues.

Any thoughts?

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Greetings fellow shellac spinner. When I rewired my stereo cartridge for dedicated to Edison Diamond Discs and ReCreation discs service, I tried the one channel out of phase method, but applied a bit differently.

I surmised that if I add the jumper between the two + leads, I could take the signal from the two negative - leads. One channel is still reversed in phase, relative to the other. Hum was not an issue, grounding one of the negative leads, iirc...

Stereo fans should realize that when one channel gets phase reversed, we are inevitably connecting the coils in series with a jumper, attempting to retrieve the most vertical only info. Set up this way, playing a lateral shellac disc, which only has lateral modulations, is all noise with the vertically oriented setup. You might want to keep this in mind when fabricating and wiring the shielded switchbox, maybe leaving some space for a do-over yields lowest noise. I would leave space, since the switch and splice/solder connections will need the best shielding, surrounding them.

Series connecting the coils can also be a way some mono collectors rewire their stereo carts for increased output level, nearly doubling opt. Jukebox folks sometimes adapt stereo carts, connected in mono, because the stereo styli are not preciously priced.

Edison's pre-1929, vertically cut discs were amazingly designed by a man with severe hearing loss. Stereo carts, used normally, have half their signal vertically modulated while half the signal is laterally modulated, since the magnetic circuit is aligned at 45 degrees x 45 degrees to the stylus.

Whatever mono connection you try with a stereo cart, the noise inherent with the unwanted modulation is still amplified. In fact, it could still be half of the signal.

What results with this Edison or Pathe vertical usage of a stereo cart is some vertical info and some lateral noise, combined together. Thus, the noise floor is audible but any music is certainly listenable.

For my experiments with these heavyweight, 1/4 inch thick, historical discs I bought as many Edison discs which had the word "...Blues" in the titles or had the term "Dance" or "Fox Trot" on the label. While some of these sounded like early jazz, none sounded bluesy. I shelved most of these discs. Their historical, musical content is still virtuous.

The best way to play these vertically cut discs is with a very rare, vertically oriented, monaural cartridge. Only a few USA companies provided these now very obscure cartridges.

The Western Electric 9B and 9A early moving coil cart had four leads. Because the coils were arranged with one coil having vertical sensitivity mounted atop the other coil having lateral sensitivity, this Universal cartridge was actually one of the first carts employed for some of the first stereo experiments.

Western Electric's competitor in the entertainment field was RCA, who also offered a Universal cartridge. Both of these carts will undoubtedly require specialist reconditioning, unless you find a prime example.

In the earlier 1930s, RCA also offered Vertical only or Lateral only phono playback carts. In the later 1930s another phono playback company arrived, with the most art-deco looking transcription tonearm, the one with the finger lift in the front and top of the pickup headshell, Radio-Music Corp. They offered both universal types as well as Vertical only or Lateral only carts.

Any of these carts and tonearms are now very rare. Both RCA and WE encouraged their existing customers who later "upgraded" their theater, sound or broadcasting equipment to return the valuable tubes and destroy the soon to be unneeded equipment ! That makes procurement of this heavy tracking phono playback gear very unobtainium...

Lastly, I did own an Edison accessory which was "grafted" onto a tonearm, designed to electrify an Edison "Reproducer" pickup head. It had a large coil with reproducer parts and a diamond stylus ! As with all the arms and carts from that era, they track in ounces or pounds, not in grams.

Speaking with a sincere Edison restorer, he reminded me that back in the day, many disc spinners were also DIY folks, like many, if not most radio listeners then. Some of these crafty folks mounted their crystal and early magnetic carts horizontally on their tonearms, extending and bending the "cantilever/armature" to play the disc's vertical modulations. "How resourceful !" (spoken in a Wizard of Oz tone)...

Using the versatile stereo cart is the practical way to listen with these discs. Keep on Groovin'....
 
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240sx4u

Technically It's LexusGuy
Fran, I was going to suggest something like what you posted before I hit the end of the post you'd made. I bet hum won't be a problem if you put it into a metal box and use good quality switches.
 
The external switch box needs to be very close to the arm and especially the preamp. Shielding and the shortest leads are super important.

With 40db+ of phono gain, that is 100x input voltage. Any stray wiring inside the switch box could cause a hum field. It is doable, certainly...

Fellow disc collector "coffee-phil" uses a similar switchbox. He has described and posted his diagram, and OP-Amp preamp scheme at the vinyl engine and/or the audioasylum, years ago...
 
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