d&b audiotechnik T-SUB

Trace the SUB path. T-SUB uses 2+/2− on NLT4/NL4, or pin 3 positive and pin 4 negative on EP5. T10 uses 1+/1−, or EP5 pins 1 and 2. A cable carrying only the TOP pair can leave the T10 working while the T-SUB receives no signal.

Both T-SUB connectors are wired in parallel. If T10 and T-SUB share a four-conductor cable, use Mix TOP/SUB with the correct setups: TOP on A and SUB on B for D12; TOP on A/C and SUB on B/D for each configured D80 pair. Also check each channel’s input routing.

In Dual Channel, the TOP and SUB contact pairs carry the same signal from that output’s amplifier channel. Do not link a T10 to a channel configured for T-SUB: it can receive subwoofer processing and be damaged.

1. Identify output mode, setup, channel and destination before changing the patch. The table below shows cabinet contacts; also check the amplifier’s output assignment table.
2. Switch off the amplifier and disconnect the cable at both ends before checking continuity and adapters. Check all four conductors in the shared path, including polarity. The connector type alone does not establish how the cable is wired.
3. With the patch verified, test TOP and SUB separately at an agreed test level. If SUB is missing, trace its input, mute, setup and conductor pair. If both work separately but not together, check the shared configuration before raising the level.

The T-SUB manual allows up to two cabinets per channel with the T-SUB setup and lists D80, D40, D12, D20 and D6 as applicable amplifiers. This limit applies to that model and setup. Check the total connected cabinet count before using the second connector.

For SenseDrive with D12, the cabinet manual requires EP5 connectors and five-conductor cabling. In Mix TOP/SUB, the sense reference is available only at OUT B. An EP5 connector at one end does not retain the extra conductor through a four-conductor NL4 section.

On the four-channel amplifier platform, LoadMatch compensates for the cable without a separate sense conductor. For D80, use its LoadMatch settings and the actual cable data. The J8 guide explains those amplifier parameters, but its wiring and cabinet limits do not apply to T-SUB.

1. Identify amplifier, firmware, connector variant and T-SUB count per channel. Keep the two-subwoofer limit separate from the four-T10 limit documented in the TOP guide.
2. If using D12 Mix TOP/SUB with SenseDrive, check the complete path from OUT B to the cabinet. Check the fifth conductor with the system switched off and disconnected; an adapter cannot create a sense path missing from the cable.
3. Record the configuration and result for each destination. NL8 and Ti-SUB are outside the wiring arrangement described here.

The 100 Hz mode lowers the T-SUB’s published upper frequency limit. The manual specifies 47–140 Hz in standard mode and 47–100 Hz in 100 Hz mode, both at −5 dB. The published lower limit remains 47 Hz.

If adding another subwoofer, identify the model, processing and position of both systems before deciding on the crossover arrangement. For a flown T-SUB or mixed array, use the rigging manual for the actual hardware and geometry.

1. Save the starting configuration: T-SUB setup, 100 Hz state, T10 CUT state, levels, polarity, delay and cabinet positions.
2. Compare standard and 100 Hz modes with the same signal, level and listening positions, first with T10/T-SUB and then with the additional subwoofer if planned. Check how the systems sum and whether the balance changes around the transition.
3. If you hear cancellation or excessive bass, test filter, level and alignment changes separately. Record what each change does. Do not assume the complete system is correct simply because each path works on its own.