home phonographs which, with their lateral-only playback systems, would only produce silence from a vertically modulated disc. After 33 RPM recording had been perfected for the movies in 1927, the speed of radio program transcriptions was reduced to match, once again to inhibit playback of the discs on normal home consumer equipment. Even though the stylus size remained the same as consumer records at either 3 mils or 2.7 mils, the disc size was increased from 12-inches to the same 16-inches as those used in early talking pictures in order to prevent the practice even further. Now, not only could the records not be played on home equipment due to incompatible recording format and speed, they would not even fit on the player, which suited the copyright holders. Two-channel high fidelity and other experiments During the same period engineers got a bright idea. Split the signal into two parts, bass and treble, and record the treble on its own track near the edge of the disc in a lateral format so that there would be no high-frequency distortion, and then record the bass on its own track in a vertical fashion to get rid of the rumble. Unfortunately, vertical grooves take up more space than lateral grooves; so when the bass track was full, starting halfway through the disc and ending up at the center, the treble track had a large amount of unused space at the end. The alternative was to record it at a wider pitch i.e. lines-per-inch in order to match up with the bass track and keep both styli in the same place, limiting the playing time to slightly longer than a single even at 33 RPM on a 12-inch disc. Another failed experiment in the late 1920s and early '30s involved recording the left channel on the left side of the disc (when held vertically with its edge facing the user) and recording the right channel on the right side of the disc. These were manufactured on twin film-company recording lathes which ran in perfect sync with one another with no variation, and were capable of, not only outside-in as well as inside-out recordings (see Radio Programming Vinyl Sequence under Gramophone record), but also counter-clockwise as well as conventional clockwise recording by mounting the cutting head wrong-way-out with a special adapter. One master was recorded conventionally and the other was recorded counterclockwise, each master was