Funk Tonstudiotechnik SAM-1C, Руководство по эксплуатации

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EINGANG LINKS
VERSTÄRKUNG LINKS 0..-20 dB
VERSTÄRKUNG RECHTS 0..-20 dB
XLR-FEM ALE
OUT L
OUT R
CINCH SYMMETRISCHE EINGANGSSTUFE LINE AUSGANGSSTUFE
MASSE
SYMMETRISCH
EINGANG RECHTS
SYMMETRISCH
J1
J3
VERSTÄRKUNG 0 (+6) dB MASSE CHASSIS
J8A
J9A
J8B
J9B
SUMMIERUNG
R24
R25
J10
J11
3 2
1
3 2
1
J2
J3
MASSE CHASSIS
AUSGANG LINKS
SYMMETRISCHE AUSGANGSSTUFE EINGANGSVERSTÄRKER
J2/J3 VERSTÄRKUNG FIX 0 dB
VERSTÄRKUNG 0..24 dB
XLR-M ALE
AUSGANG RECHTS
CINCH
SYMMETRISCH
SYMMETRISCH
J4
J5
DÄMPFUNG
DÄMPFUNG 0...-X dB
MASSE
R1
R2
R1b
R2b
22kOhm
22 kOhm
EINGANG 1R
EINGANG 1L
J6A
J7
SIGNAL PATH AMPLIFIER MODULES SAM-1C
_____________________________________________________________________________________________________
2-CHANNEL DIFFERENTIAL AMPLIFIER MODULE SSIM-04Mc
On analogue balanced audio lines, the signal level is often higher than on unbalanced cabling. When
converting from balanced to unbalanced technology, an adjustable level reduction is therefore usually
desired. The differential amplifiers (desymmetrical amplifiers) of the SAM-1C normally allow an
attenuation in the range of -20...0dB, depending on the setting of the spindle trimmers. For special
cases, however, amplification of the audio signal is also possible. For this purpose, solder jumpers J1 for
the left and J3 for the right channel are provided on the SSIM-04Mc modules. If these are closed, the
corresponding channel works with +6 dB amplification in the input stage. The gain adjustment range is
then approx. -14..+6 dB. The max. permissible input voltage decreases by 6 dB to approx. +18 dBu
when the jumpers are closed. Jumpers 8..11 allow summation or distribution of the input signals within
the module.
Circuit zero and chassis are separated from each other in the SAM-1C. Pin 1 of the XLR socket is
connected to circuit zero and the ground connection (shown in black in the diagram) of the
corresponding RCA socket, the XLR housing is connected to the chassis (protective earth connection
green).
2-CHANNEL BALANCING AMPLIFIER MODULE SSOM-04Mc
On unbalanced audio lines, the signal level is often lower than on analogue balanced cabling. When
converting from asymmetrical to symmetrical technology, an adjustable gain will therefore usually be
required. The SAM-1C's balancing amplifiers normally allow a gain in the range of 0...+24 dB,
depending on the setting of the spindle trimmers.
For special cases, attenuation of the audio signal is also possible. For this purpose, solder jumpers J4
for the left and J5 for the right channel are provided on the SSOM-04c modules. When these are closed,
the resistors R1 and R1b (R2 and R2b) work as voltage dividers of the corresponding channel. The
attenuation achieved depends on the resistance ratio of these two resistors and must be calculated
accordingly. The resistors R1b/R2b are 22 kΩ. For an input attenuation of 6 dB, for example, R1/R2
must also be changed to 22 kΩ. R1 and R2 have a resistance of 330 Ohm in the standard version.
Suitable resistors of the type "Micromelf" or SMD-0204 can be requested if required. After setting the
damping jumpers, the input impedance of the corresponding channels is reduced to values between
22...220 kΩ, depending on the dimensioning of the resistors R1 or R2. Jumpers 6 and 7 enable the
distribution of an input signal to both amplifier trains.