SPL SMC

5.1 Surround Sound Monitor Controller

• Analog monitor controller for 5.1 surround sound and stereo sources
• 6-channel analog volume control with speaker management
• Two 5.1 sources and two stereo sources for comparing productions
• DB25 balanced input for direct connection to a DAW
• Automatic -10 dBV consumer-level compensation for DVD and Blu-ray players
• Global mute, per-speaker mute, and mono function for front and rear pairs

The SPL SMC is a 5.1 surround monitor controller considered a standard in multichannel listening. It combines 6-channel analog volume control and speaker management in a compact desktop unit, allowing you to work on both 5.1 and stereo mixes using the same listening system. It is designed for post-production studios, audiovisual mixing, broadcast control rooms, and project studios that produce surround sound content.

6-channel surround volume control for 5.1 and stereo mixes

In a 5.1 system, the levels of all speakers must vary together; otherwise, the balance between the front, center, rear, and subwoofer channels shifts as you adjust the listening level. The SMC manages all 6 channels with a single analog volume control, keeping the surround image stable at any listening level.

Source selection: two 5.1 inputs and two stereo inputs

During monitoring, you’re constantly comparing two productions—for example, the mix you’re working on and a reference track. That’s why you can connect two 5.1 sources and two stereo sources to the SMC and switch between them in an instant.

DB25 input for the DAW

The DAW connects via a balanced DB25 input. In the output routing, assign channels 1 through 6 to the 5.1 mix and channels 7 and 8 to the stereo mix—so with just one cable, you have both formats ready for listening.

Level Compensation for DVD and Blu-ray Players

Consumer DVD or Blu-ray players are often used for comparisons; they operate at a nominal level of -10 dBV, which is approximately 7.8 dB below the studio standard of 0 dBu. The SMC automatically compensates for this difference, allowing you to compare your mix to a commercial reference at the same volume level.

Speaker Control: Mute, Mono, and Safety

Each speaker can be turned on or off individually to monitor one channel at a time or isolate the subwoofer. The front and rear stereo pairs can be switched to mono separately, which is useful for checking compatibility and phase. The Mute All button instantly mutes all outputs: if your DAW accidentally sends a full-scale signal, you can protect your speakers and your hearing in an instant.

Slave Out for Multichannel Metering

The balanced inputs are passively routed to the Slave Out on the DB25 connector, where you can connect, for example, a multichannel metering system without interfering with the listening path.

Balanced Speaker Outputs via TRS Jacks

The speaker outputs are balanced via TRS jacks. If you use mono TS connectors, the signal is automatically unbalanced, allowing you to connect monitors with unbalanced inputs without adapters.

SPL SMC Technical Specifications

• Type: 5.1 surround and stereo monitor controller
• Sources: 2 x 5.1, 2 x stereo
• Connections: DB25 and balanced TRS jacks, RCA
• Slave Out: DB25, passive feed-through of balanced inputs
• Speaker Outputs: Balanced TRS jacks
• Functions: 6-channel analog volume control, per-speaker mute, Mute All, front and rear mono, -10 dBV level compensation
• Maximum input level: 21 dBu
• Input impedance: 50 kΩ (DB25 and jacks), 10 kΩ (RCA)
• Frequency response (-3 dB): 10 Hz – 100 kHz
• THD+N (10 Hz – 22 kHz, 18 dBu): 0.002%
• Noise (A-weighted): -98 dBu
• Common-mode rejection (1 kHz): 70 dB
• Dynamic range: 119 dB
• Analog audio operating voltage: ±15 V
• Power supply: internal linear power supply with toroidal transformer
• Mains voltage: 230 V AC / 50 Hz or 115 V AC / 60 Hz
• Fuses: T 315 mA (230 V), T 630 mA (115 V)
• Power consumption: max 10 W
• Dimensions (W x H x D): 272 x 91 x 220 mm
• Weight: 2.3 kg
• Weight with packaging: 3.25 kg