Sound Devices - 633 Field Mixer/Recorder

The 633 is a compact, six-input mixer with integrated 10-track recorder featuring PowerSafe technology. It offers six analog inputs and records to SD and CompactFlash memory cards. The 633 is designed for audio professionals requiring go-anywhere portability, without compromising recording or mixing capability.

Input and Output Flexibility

The 633 offers three high-bandwidth mic/ line inputs on XLR connectors (3+3), complete with phantom power, high-pass filter, input limiter and variable pan. Three additional line-level inputs on TA3 (mini-XLR) connectors offer flexibility for more complex productions. All inputs are assignable to its six output buses, left/right plus Aux 1/2/3/4.

10-Track Recording

All six inputs plus output buses left/right and Aux 1/2 can be recorded to individual tracks. The 633 offers 10-track 24-bit, 48 kHz uncompressed WAV recording (96 kHz and 192 kHz sampling up to six tracks) to SD and CompactFlash memory cards. The two cards can be set independently, recording either identical material for a real-time backup, or combinations of WAV and time code stamped MP3 files.

Quad Power

Powered by a unique Quad Power supply with PowerSafe technology, the unit is operational from any of four power sources. Sources can include external DC (12-18 V), two removable 7.2 V L-type lithium ion cells, and six internal AA batteries. The 633 automatically switches from one power supply to the next when power is exhausted or removed. With its combination of power sources, the 633 can operate for a full production day on batteries alone.

PowerSafe Technology

When all power sources are removed or depleted, the unit’s PowerSafe circuitry is activated. PowerSafe keeps the 633 operating for up to 10 seconds and ensures that all file operations are fully closed and the unit gracefully shuts down.

Two second power on-to-recording. Never wait on sound!

Ease-of-Use & Full Size Controls

Clear, fast, easy to navigate controls and interface; visible in all light conditions, configurable metering and display.

Integrated Time Code

The 633 integrates a rock-steady Ambient time code generator, supporting all common rates and modes. In addition to time code, the 633 supports extensive file metadata. Metadata is entered from either the front panel or from an attached USB keyboard.

Built for the Field

Designed to withstand the extremes of field production, the 633’s small, lightweight, compact chassis is made from molded, metalized carbon fiber. It is built on Sound Devices strong heritage of high performance audio mixers, audio recorders, and video recorders.

Additional Features

AES input, two-channel AES3 or AES42, four channels of AES output.
Clear, fast, easy to navigate controls and interface; visible in all light conditions, configurable metering and display.
Stereo Linking, MS and L/R.
Input delay selectable on all six inputs plus output bus delay on all six buses.
User-configurable headphone presets plus a headphone favorite mode for quick source selection.

633 Specifications

Analog Inputs

Frequency Response

10 Hz to 40 kHz ± 0.5 dB, -3 dB @ 65 kHz (192 kHz sampling rate reference 1 kHz)

THD + Noise

0 .09% max (1 kHz, 22 Hz–22 kHz BW, fader at 0, 0 dBu output)

Equivalent Input Noise

-126 dBu (-128 dBV) maximum. (22 Hz – 22 kHz bandwidth, flat filter, trim control fully up)

Input Types

XLR Mic: active-balanced for use with ≤600 ohm mics, 4k ohm actual; 12V or 48V phantom power, 10 mA max
XLR AES: AES3 or AES42 (10 V power), SRC
XLR Line: active-balanced for use with ≤2k ohm outputs, 10k ohm actual
TA3 Line: active-balanced for use with ≤2k ohm outputs, 10k ohm actual
RTN (3.5 mm): unbalanced stereo for use with ≤2k ohm outputs, 30k ohm actual

Maximum Input Level

XLR Mic: 0 dBu (0 .78 Vrms)
XLR Line: +40 dBu (80 Vrms)
RTN (3 .5 mm): +24 dBu (12 .4 Vrms)

Maximum Gain

Mic-In-to-Line-Out: 91 dB
Mic-In-to-Aux-Out, -10 Out: 77 dB
Line-In-to-Line-Out: 39 dB

High-Pass Filters

Sweepable 80 Hz to 240 Hz, 12 dB/oct at 80 Hz, 6 dB/octave at 240 Hz

Microphone Powering (each analog Input selectable)

12 V Phantom: through 680 ohm resistors, 10 mA per mic available
48 V Phantom: through 6 .8k resistors, 10 mA per mic available

Analog Input Limiters (Inputs 1-3)

Affects the output of the mic preamps only (‘Trim’ stage) · +16 dBu threshold (fixed)
20:1 limiting ratio
1 mS attack time
500 mS release time

Digital Input Limiters (Inputs 1-6)

Post-fader
+6 dBu to +18 dBu threshold (adjustable) · 20:1 limiting ratio
1 mS attack time
500 mS release time

Digital Inputs

AES42

AES42 Mode 1, provides +10 V Digital Phantom Power

Analog Outputs

Output Type

XLR Line: Active Balanced for use with ≥600 ohm inputs
XLR -10: Active Balanced for use with ≥10k ohm inputs
XLR Mic: Active Balanced for use with ≥600 ohm inputs
TA3 Active Balanced Mic/Line: pin-2 and 3 driven, for use with ≥3k ohm inputs · X3,X4 (3 .5 mm): Unbalanced, stereo, for use with ≥6k ohm inputs
Headphones (1/4”): Unbalanced, stereo, for use with 8-2k ohm headphones

Output Impedance (ohms actual)

XLR and TA3 balanced outputs: 100 ohms at Line setting, 3 .2k ohms at -10 setting, 150 ohms at Mic setting
TA3 Balanced Outs: 1k ohms at Mic and Line settings · X3,X4 (3 .5 mm): 100 ohms
Headphones (1/4”): 100 ohms

Line Output Clipping Level (1% THD)

20 dBu minimum with 10k load

Maximum Output Level

Line: +20 dBu (7.8 Vrms)
-10: +6 dBu (1.5 Vrms)
Mic: -20 dBu (0.078 Vrms)
Aux 3/4: +6 dBu (1.5 Vrms)

Output Limiters

Affects the outputs of the mixer
Threshold selectable from +4 dBu to +18 dBu, 1 dB steps · 20:1 limiting ratio
1 mS attack time
500 mS release time

Maximum Gain – Typical (Trim, Fader, Master, Phones, RTN fully up)

	MIC Level Input	LINE Level Input	RTN
Master Outs (XLR) @ LINE	91 dB	51 dB	–
Master Outs (XLR) @ -10	77 dB	37 dB	–
Master Outs (XLR) @ MIC	51 dB	11 dB	–
X3, X4 Outs (3 .5 mm)	77 dB	37 dB	–
Headphones (1/4”)	107 dB	67 dB	5dB

Digital Outputs/Recorder

AES3 Output

Transformer-balanced AES Out A,B on XLR
110 ohm, 2 V p-p, AES and S/PDIF compatible with RCA adaptor

Sampling Frequency

44.1 kHz
47.952 kHz
48 kHz
48.048 kHz
88.2 kHz
96 kHz
192 kHz

A/D

24 bit

A/D Dynamic Range

114 dB, A-weighted, typical

Recording Storage Type

SD, SDXC, SDHC Card
FAT32 or exFAT formatted, will format media on-board
CompactFlash (CF)
FAT32 formatted for CF and SD <32 GB, exFAT for SD cards >32 GB, will format memory cards in-unit

File Type

Record: WAV (Broadcast Wave File format), polyphonic or MP3
Playback: WAV (Broadcast Wave File format), polyphonic or MP3

Timecode and Sync

Modes Supported: off, Rec Run, Free Run, 24h Run, External
Frame Rates: 23.976, 24, 25, 29.97DF, 29.97ND, 30DF, 30ND
Accuracy: Ambient generator, 0.2 ppm (0.5 frame in 24 hr)
Time Code Input: 20k ohm impedance, 0.3 V – 3.0 V p-p (-17 dBu – +3 dBu)
Time Code Output: 1k ohm impedance, 3.0V p-p (+12 dBu)

Sample/Timecode Accuracy

± 0.2 ppm (0.5 frames per 24 hours)

Power

External: 10-18 V on locking 4-pin Hirose connector, pin-4 = (+), pin-1 = (-).
Removable x 2: 7.2 V (nominal) Sony L-type Li-ion, operational from 6.5–8.5 V,
Internal: accepts 6 AA-sized (LR6) batteries, 1.2-1.6 V nominal (NiMH rechargeable compatible)