16+16 Channel MADI Interface


Which AD/DA converters are used in Madison?

High quality professional grade analogue to digital and digital to analogue converters are used surrounded by SPL's analog 36V rail environment. This combination creates the synergy for Madison's unique high-quality sound.


What sample rates does Madison support?

44.1, 48, 88.2, 96, 176,4, 192 kHz.

With the front panel RATE button you select both the base sample rate (44.1 or 48kHz) and the multiplier (x2, x4) to easily specify one of the 6 available sample rates.


What bit depth are the Madison convertors?

24­ Bit.


What are the audio performance figures for Madison?

Analog Inputs

  • S/N: 115 dB (A-weighted, 48?kHz)
  • Dynamic Range: 115 dB (-60?dBfs, A-weighted, 48?kHz)
  • S/(N+D): 102 dB ( -1?dBfs, 48?kHz)
  • Interchannel Isolation: 110 dB (48?kHz)
  • Passband Response: 22 kHz (-0.02dB, 48kHz)
  • Passband Ripple: +/- 0.005 dB (Decimation-LPF, 48kHz)
  • Stopband Attenuation: 100 dB (Decimation-LPF, 48kHz)

Analog Outputs

  • S/N: 115 dB (A-weighted, 48kHz)
  • Dynamic Range: 115 dB (-60dBfs, A-weighted, 48kHz)
  • S/(N+D): 100 dB (-1dBfs, 48kHz)
  • Interchannel Isolation: 110 dB (48kHz)
  • Passband Response: 21.8 kHz (-0.04dB, 48kHz)
  • Passband Ripple: +/- 0.06 dB (Digital Filter, 48kHz)
  • Stopband Attenuation: 70 dB (Digital Filter, 48kHz)


Can Madison operate at various analog reference levels?

Yes, four reference levels are available via the front panel Ref button: 24dBu, 22dBu, 18dBu, 15dBu. These are provided to enable you to globally change the Madison analog reference level to match your studio analog equipment.


How do I interface unbalanced equipment with Madison?

You can establish unbalanced connections easily and without adaptors. It is important to pay attention to the correct wiring of the three balanced lines per channel: for an unbalanced wiring, pin 1 (GND) and 3 (cold) must be connected.

Notes: Connections to RCA and TS Jack inputs or outputs are always unbalanced. Connections to TRS inputs or outputs may be balanced or unbalanced. In any case we recommend to use readily configured cables from DB25 to the respective RCA or TS/TRS connector to dispense with adaptors. Ask your dealer for configured cables. With the DB25 pin configuration diagram (see answer to next question) any audio expert can ensure to select or configure appropriate cables.


Which wiring scheme do the Madison DB25 connectors follow?

The analog DB25 sockets follow the TASCAM standard.


What type of metering does Madison have?

Ergonomic, distance­-readable 3 state LED meters for clear level status indication of any analog I/O channel.

  • Green LEDs indicate a signal is present (level ? ­-42dB)?
  • Yellow LEDs indicate the level is optimal (level ? -­6dB)?
  • Red LEDs indicate an overload at the input and a clipping at 0dB at the output (level ? -­0.1dB).


What is the Madison USB port for?

The USB port on the Madison is a service port for SPL engineers. It may also be utilized by the user to update the internal operating system/firmware of the Madison whenever such updates become available.

Important: The USB port is not an audio interface!


Is the Madison power supply auto­sensing?

Yes. Make sure your local power outlet operates within these specs: 90-264 V AC, 50 Hz / 60 Hz, P max. 36W.


How heavy is Madison?

3,05 kg (3,17kg with 2nd Power Supply)
6,72 lbs (6,99 lbs with 2nd Power Supply)

Can SPL recommend any MADI cards or interfaces to use with Madison for MAC or PC?

There are plenty of MADI cards with PCIe interface and also a growing number of USB devices featuring MADI I/O. And all of them should work flawlessly with Madison over MADI.


Which MADI modes does Madison support?

Today, two general MADI modes are known, 56CH and 64CH mode. And there are two different ways to wrap up channels at higher sample rates: High Speed and Low Speed mode (also known as Legacy or SMUX mode).

All supported by Madison.


About MADI Modes

56CH mode: At "normal" sample rates (44.1 & 48kHz) the MADI stream contains 56 audio channels and allows to varispeed the signal +/- 12.5%.
64CH mode: At "normal" sample rates (44.1 & 48kHz) the MADI stream contains 64 audio channels and does not allow positive varispeed values.

High Speed Mode
Only selectable at "double" (88.2-96kHz) or "quad" (176.4 or 192kHz) sample rates.
Example at 96kHz in 64CH mode: In order to carry twice the amount of information per channel, the MADI frame rate is transmitted at higher speeds at 96 kHz, but the frame size is reduced to 32 slots (one data slot per channel). Since the frame and the speed increase, MADI still consumes the same bandwidth. In High Speed mode each channel is allocated one data slot. At 96kHz MADI can carry 32 channels of audio (16 at 192kHz).

Low Speed Mode
Only selectable at "double" (88.2-96kHz) or "quad" (176.4 or 192kHz) sample rates.
Example at 96kHz in 64 CH mode: In Low Speed mode the frame rate stays at 48kHz and the frame size is also kept at 64 slots, however each channel uses two consecutive data slots. Thus, the frame is larger but the speed is slower, so MADI still provides the same bandwidth. Since each channel is allocated two consecutive data slots, MADI can still provide 32 channels of audio at 96 kHz (or 16 at 192kHz).
Low Speed Mode is not often required and High Speed Mode is most common when you need to operate at double or quad sample rates. However, in environments with MADI equipment from different generations, and also in mixed digital environments, Low Speed Mode may prove necessary.

NOTE: High Speed and Low Speed Modes are only selectable when double or quad sample rates are selected (88.2-192kHz).


How many channels are available over MADI?

At 44.1/48kHz = 64/56 channels (64/56CH Modes)
At 88.2/96kHz = 32 or 28 channels (64/56CH Modes)
At 176.4/192kHz = 16 or 14 channels (64/56CH Modes)


How many Madison units can be used simultaneously and how does it handle latency compensation?

Up to four Madison units can be daisy-chained on 1 MADI connection for a maximum of 64 I/O. The units should be assigned the appropriate position inside the MADI chain via the front panel CHAIN button and clocked properly via either Word Clock or MADI.

Earlier units in the chain are appropriately delayed to compensate for the extra latency induced in the MADI chain, resulting in up to 64 analogue I/O being sample accurately in sync. If only one Madison device is present the Chain number should be set to 1.

Sample Rates 44.1 and 48 kHz

Position64CH Mode56CH Mode

Sample Rates 88.2 and 96 kHz

Position64CH Mode56CH Mode

Sample Rates 176.4 and 192 kHz

Position64CH Mode56CH Mode

NOTE: At 88.2 and 96kHz up to two Madison units can be used simultaneously to provide up to 32 MADI channels. At 176.4 & 192kHz, MADI capacity provides 16 channels so that only one Madison unit can be used.


What type of MADI connectors does Madison have?

Madison provides optical MADI SC connectors. The MADI cables used to connect MADI should be multimode, 50/125 or 65/125, with SC connectors. Single mode cable is not compatible.

If you need to connect Madison to devices that use coaxial/electrical MADI connectors then you will need to use an appropriate optical/coaxial MADI converter.


How far can optical MADI cables run?

The fibre MADI links used inside Madison are capable of transmitting up to 2km/ca. 1.5 mile. This allows for a substantial distance between the Madison and other MADI equipment. This distance can be increased by using active MADI repeaters.


Does Madison support Varispeed operation?

Yes, in 56, 28 and 14-channel MADI mode ±12.5% varispeed is supported.


How can Madison be clocked?

Madison can be clocked in 3 ways chosen via the front panel CLOCK button

  • INT: the internal clock is used and distributed across Word Clock and MADI outputs. All other connected MADI devices must be set to clock from this signal in Slave mode via either Word Clock or MADI.
  • WORD (Word Clock): Madison can be set to clock from a Master Word Clock source via its Word Clock input. The correct sample rate should be chosen using the RATE button.
  • MADI: Madison can lock to an incoming clock signal embedded in the MADI stream from another device. The correct sample rate should be chosen using the RATE button.


Why is the CLOCK button flashing?

If the currently active sample rate LED is flashing, it means that the Madison cannot lock to the selected sample rate.? When switched to INT clock, the sample rate that Madison is measuring at the MADI input does not match. If this happens and an external Clock (Word or MADI) is selected, the clock source is either not active or not connected at all, the external clock operates outside of the Madison's standard sample rates, or it exceeds the maximum deviation of ±12.5% for varispeed.


Why is the MADI Mode LED flashing?

If the currently active MADI mode LED is flashing, the Madison has detected a MADI mode mismatch between the current setting and the connected device (monitored at the MADI input).
Press the MADI button until the conflict has been resolved and the LED stops flashing, or change the external device's MADI mode to match Madison's settings.


Can the Wordclock Input be terminated?

A termination switch is available on the back of the unit to provide proper termination. If no connection is made on the Word Clock Input and the Wordclock Out is used to clock an external device the switch should be engaged.


Is Madison compatible with Frame Clock?

Yes. At higher sample rates (88.2­-192 kHz) Frame Clock is used as soon as the MADI Lo Mode is selected.


What is the latency from AD In to MADI Out and from MADI In to DA Out?

The ADC-side has the following latencies :

@ 48kHz : 39 samples : 0.812ms

@ 96kHz : 39 samples : 0.406ms

@ 192kHz : 36 samples : 0.187ms

The DAC-side has the following latencies :

@ 48kHz : 70 samples : 1.458ms

@ 96kHz : 70 samples : 0.729ms

@ 192kHz : 70 samples : 0.364ms

Can I use Madison to integrate my outboard gear into my DAW?

Yes you can. Most DAWs provide an I/O plug­in with latency compensation to handle this type of situation. In the PDF "DAW Integration" (right column/Manuals) we describe the integration for the four common DAW softwares Logic®, Cubase®/Nuendo® and ProTools®.

The outboard unit should have its analog inputs and outputs connected to Madison. For information on connecting to unbalanced inputs and outputs see "Features and Specificatons" > "How do I interface unbalanced equipment with Madison?" above.