Most of these have long since made their way to the scrap heap. I found three recently, so if you look, and are lucky, a few more may turn up. This is the phonograph reproducing unit used to pick up the sound from the Vitaphone discs, which was one of the first methods used to provide sound tracks for talking pictures. It was a professional instrument, and the state-of-the art for disc reproduction, in the late 1920's.

I have discovered that it is GREAT for recording records that were made between 1900-1930. The reproducer is magnetic, and has a very clean, linear quality. The signal output is huge, with peak output perhaps reaching nearly a volt. This means that it can be attached directly to most computer sound cards, and used with no pre-amplification. AC hum, and electronic noise is so far below the actual signal level, that it will never be a problem in the recording.

It easily fits with steel phonograph needles. It will also track with some weight, very similar to the conditions used when playing the records on their original, acoustic equipment (which is what they were designed for). The result of all of this is a much quieter recording, much more in line with the actual tonal quality originally intended.

The spectral display, shown above, is from a 4 second sample, recorded with this system. The record was issued around 1928, so it was electrically recorded. This spectrum represents the signal, which was picked off of the playing record, rather than being an example of the potential frequency response of the reproducer, itself. The record had useful signal between 200-4000 Hz. Notice how well the recording rides above the higher frequency surface noise, above 3000 Hz.

One note, for those of you who are using the lightweight, small signal magnetic cartridges. Most phono pre-amplifiers perform RIAA equalization, which did not exist, in these early recordings. Recording, with such a pre-amp, will boost your bass, and limit your higher frequency tones. If you use such a system, you will need to post filter your recordings, in a way opposite to what the RIAA equalization changed.

The above two examples are excerpts from Edward M. Favor's 'Theodore', recorded around 1905. The record is loud and clear, but does have a normal amount of surface noise and wear. The spectrums shown above are each from this same record, showing the same slice of time, about one second. Time is represented from left to right, and frequency is displayed from the bottom, to the top. Color shows how intense the energy of a given frequency is, at a given time. Black represents no energy, while yellow indicates the greatest energy. This record's meaningful signal is mostly between 250-3000 Hz. Most of the color displayed should be below the 5000 level, as seen at the right, in the spectrum graphs. Color seen above this level, will indicate noise.

Notice how immune the second example is to the surface noise, and minor defects! The light weight, modern cartridge requires a large amount of amplification, and is very sensitive to every inflection in the surface of the record. The 4A reproducer is much heavier, and plays with a fresh steel needle. The actual recording in the record's groove produces a very high voltage signal, with the 4A, compared to the Pickering. The much smaller amount of surface noise cannot produce nearly the same level of signal, so the result will be a much quieter recording.

These modern magnetic cartridges are designed for stereo, and require a large amount of pre-amplification. They are designed to pick up the vibrations produced from vinyl LP's, which were far weaker than the massive vibrations produced by playing an old acoustic record. Stereo LP's use both lateral and vertical modulation, on the record surface. In other words, one channel is 'shaking', while the other channel 'bounces'. Modern cartridges are sensitive to vibration in both directions. Victor and Columbia type 78's only use lateral, or 'shaking' modulation. Any vertical modulation is probably only noise. The 4A reproducer is designed only for lateral modulation, and is very immune to anything else, so the result is a quieter recording.