Sound Devices 302 - Manual (Page 22)

302 User Guide and Technical Information
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v. 3.6 Features and specifications are subject to change. Visit www.sounddevices.com for the latest documentation.
Advanced Gain Structure and Interconnection
The 302’s unique output attenuator circuit is adjusted in the Setup Menu. This can be thought of as
a master gain control which comes after the 302’s output meter. This circuit allows the user to match
the 302’s output level to any recording device. When properly set, the dynamic range of the system is
maximized and the 302’s meters will “match” the recorder’s meters.
For simple interconnection the following three setting are identical to setting the output switch on
the 442 mixer to “Line”, “Tape”, or “Mic.”. 0 dB – Line , 10 dB – Tape , 40 dB – Mic .
However, to tailor the 302’s outputs exactly to the recording device, the 302’s output can be
attenuated from full line-level in 2 dB steps from 0 to 16 dB (line/tape levels), then in 2 dB steps from
40 to 56 dB (mic levels). So if 40 dB of attenuation is “too hot” for a given device’s mic input, the
attenuator could be set to 50 dB or more.
When interconnecting the 302 to any recording device, the best way to set the level between them is
to match the 302’s output clipping level with the recorder’s input clipping level. When this is done
and the recording device’s input gain controls are kept fixed, two things will happen:
1. The dynamic range of the recording is maximized.
2. All level metering can be done via the 302’s meter.
The recorder’s level meter can be ignored since the only way for the recorder to clip is for the 302
to clip. The 302’s meters match the recorder’s meters in that the clip points match. Because most
recorder’s meter ballistics and scale are different, it is impossible to make the 302 meter exactly
match a given recorder’s meter. However, this is irrelevant if the clip levels match.
Full Scale Tone
The following information is intended for users with advanced knowledge of interconnection and gain
structure.
To facilitate matching the clipping levels of the 302’s output to the recorder’s clip level, the 302
includes a full-scale tone output function. “Full scale” is the same as “clipping level.” To activate this
full scale tone, turn on the tone switch while in the Setup Menu –30 position. Be extremely careful
when doing this, as a full-scale tone is extremely loud and can hurt the operator’s ears. Make sure to
turn down the headphone level and the level going to any amplifiers, etc. from the 302.
The advanced way to set gain structure is as follows:
1. Connect 302’s XLR outputs to the recording device.
2. Enter Setup Menu (
see The Setup Menu ).
3. Turn down headphones and any amplifiers connected to the 302’s other outputs.
4. Turn on the tone oscillator via its switch.
5. Turn the recording device’s input gain control to its detented point (or half-way if no detent).
6. Adjust the 302’s output level via the up/down buttons until the recorder is just shy of
clipping as indicated on its meter.
7. If the 302’s Output level is at 0 dB and the recorder is not to its clip level, increase the
recorder’s gain control until it is to the clip level.
8. Fix the recorder’s gain controls with tape so that they do not get bumped.
9. Exit the 302’s Setup Menu by pressing the PK/VU switch until the startup sequence happens.
Note: The Setup Menu must be exited in this manner or else the setting will not be saved.
10. It is recommended that the 302’s limiters be turned on at all times, as they will not activate
until just before clipping.