Technical Details
Brand: Ferrograph
Model:Series 6
Category:Mid High Fidelity
Application:Consumer
Electronics:Hybrid
Equalization:NAB
Country of Manufacture:United Kingdom
Release dates:1966 - 1969
Original Price: $132
Tracks:1/2 Rec/PB
Speeds: 1 7/8, 3 3/4, 7 1/2, 15
Max Reel Size("): 8"
Number of heads: 3
Dimension: 17¾ wide x 18¼ deep x 9¾ ", with lid (451 x 463.5 x 247.5 mm)
Head Composition: Permalloy
Head Configuration: Stereo
# Motors: 3
Auto Reverse?:No
Voltage(s): 110-120v
Frequency Response:7½ ips: 30Hz - 15kHz (3 dB)
Wow and Flutter:0.16% at 7.5 in/s
Signal-to-Noise Ratio:52dB
Sound quality rating:6 / 10
Long-term reliability rating: 7/ 10
Additional Details
Description
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.
Additional Info
Year 1966
Price when new (in the UK) £ 132
Track system Half track stereo, quarter-track also available
Heads Three
Motors Three
Maximum reel size 8¼”
Tape speeds 15, 7½ & 3¾ ips OR 7½ , 3¾ & 1 ips
Frequency response (all 3 dB) 7½ ips: 30Hz – 15kHz; 3¾ ips: 30 – 10kHz; 1 ips: 30 – 5kHz
Wow & flutter 0.16% at 7.5 ins/sec
Signal to noise ratio Unweighted, including hum, 52dB
Bias frequency 68 KHz
Valve complement 3 x EF86, 1 x EL84, 1 x ECC82 & 1 x ECC83 plus transistorised output stage of 2 x V30/201P (Newmarket)
Audio output power 2½ watts into 15 ohms
Speaker(s) Internal 10″ x 6″, socket on front panel for external speaker
Dimensions 17¾ wide x 18¼ deep x 9¾ “, with lid (451 x 463.5 x 247.5 mm)