Revox A77

11
11
II
I.
Reproducer Test Tapes NAB 7 1/2 ips for
REVOX A77 Dolby 50/3180 µsec
(recording of Nov.30 1971)
The tapes contain the following frequencies and levels:
1 kHz 30 s AMPEX Operating Level
1 kHz 8 s — 10 dB
10 kHz 60 s — 10 dB
Frequency response test section: all levels — 20 dB 8 sec.
1k, 40, 63, 125, 250, 500, 1k, 2k, 4k, 6,3k,
8k, 10k, 12,5k, 14k, 16k, 18k
1k — 10dB
DIN 19 S ( 70 µsec) Standard Test Tape issue 1970,
No. 5608 was used as the frequency response reference.
An Ampex Test Tape ( Nov. 71) was used as a level reference.
Distortion measured off tape, 500 Hz
To obtain the correct frequency response the following Peak Level ( assumed to be + 6 VU )
correction factors were used ( 70 µsec. to 50/3180 µsec).
REVOX A77 with DOLBY Noise Reduction System,
Additional Technical Data
All measurements taken with REVOX 601 tape, DOLBY
electronics switched on.
2- Track Version ( values for the 4- Track Version are shwon
in parenthesis)
Signal to Noise Ratio, off tape, weighted as per CCIT:
At 7 1/2 ips. better than 67 dB ( 65dB)
At 3 3/4 ips. better than 64 dB ( 62 dB)
Weighted as per ASA A:
At 7 1/2 ips. better than 70 dB ( 67 dB)
At 3 3/4 ips. better than 67 dB ( 65 dB)
40 Hz
60
125
250
500
1 k
2
4
6,3
8
10
12
15
+ 3,6 dB
+ 1,8
+ 0,1
— 0,4
0,2
O
+ 0,7
+ 1,7
+ 2,1
+ 2,3
+ 2,4
+ 2,5
+ 2,5
The DIN Standard Test
Tape was used because
the Ampex tape con-
tains different frequen-
cies and it does not
extend beyond 15 kHz.
At 7 1/2 ips. better than 1.0 % ( 1.5 %)
At 3 3/4 ips. better than 1.5 % ( 2.0 %)
Operating Level 0 dB ( 100 %):
At 7 1/2 ips. better than 0.5 % ( 0.5 %)
At 3 3/4 ips. better than 0.5 % ( 1.0 %)
All other performance data are identical with the data for
the standard version of the A77 recorder.
12.1.4.