Country of Manufacture:United Kingdom
Speeds: 3 3/4, 7 1/2, 15
Max Reel Size("): 10.5"
Number of heads: 3
Head Composition: Permalloy
Head Configuration: Stereo - Stacked
# Motors: 3
Frequency Response:7½ ips: 30Hz - 15kHz (3 dB)
Wow and Flutter:0.16% at 7.5 in/s
Sound quality rating:7 / 10
Long-term reliability rating: 7 / 10
This machine was a half-track stereo machine, and it was also produced as a quarter track version. It had 3 speeds, 7½ , 3¾ and 1 7/8 ips OR 15, 7½ and 3¾ ips.
Three tape heads meant off tape monitoring was possible, and a mono-only transistorized amplifier of 2.5 watts output fed a single speaker, the monitoring could be switched between the left or right channels or the sum of both.
The groups of knobs were left to right, ganged microphone levels, ganged line input levels, and line output level. Inputs and output was on quarter inch mono jack sockets on a rear panel.
The single recording level meter was a peak reading device, not quite true peak program metering, but very reliable, allowing consistent and repeatable recording levels to be achieved with ease. It was damped, so that it rose fast and dropped slow, so that the true peak reading could be established.
Incidentally, the series 632 was one of two machines produced using the same deck. The other was the Vortexion CBL. This had separate record/play amplifiers placed either side of the central deck, which made it rather a large machine.
Although it had peak reading meters, unlike the Ferrograph, they went berserk, having no damping at all, which made setting a consistent level a nightmare. However, the main difference between the Ferrograph and Vortexion was the fact that the latter was designed to operate vertically, even before Japanese got in on the act. The proper use of the Ferrograph hublock reels made this possible.
It also had variable bias, and this could be measure using the meters. The microphone inputs were true low impedance, 30 ohms. and a high impedance line input. This too was a great machine.
Returning to the 632, 634, these were the last of the tube stereo tape recorders produced by Ferrograph, and were quite superb. Reliable, consistent quality recordings at all times.