The AMS S-DMX is a dual independent channel, microprocessor-controlled digital audio processor. It features two completely independent channels with precisely controlled delay times, adjustable without compromising the 18kHz bandwidth, which remains constant regardless of the selected delay amount. The unit allows for a total delay of over thirty-two seconds, distributed across the two channels.
Its modular and software-based design supports the integration of new technologies and techniques, ensuring the system remains up to date as advancements occur. Standard memory backup prevents data loss during power downs.
Adjustable input and output levels accommodate units with non-standard signal levels. An intelligently spliced, de-glitched pitch change is included for both channels, enabling pitch shifts of up to one octave above or below the original frequency.
Regeneration controls are available for both channels, with an option to switch to single line input (channel ‘a’ feeding both delay lines) and a switch for mixing outputs for special effects. The ‘Nudge Buttons’ feature enables silent delay sweeps in 25µS increments and allows for nudging of pitch ratios and loop extremities.
Additional functionalities include phase switching for channel ‘a’ relative to the original and channel ‘b’, a reset switch for computer initialization, and a complete store clear instruction (D0). Optional flight cases are available for the AMS S-DMX, accommodating multiple AMS Neve systems.
Designed for rack mounting (3.5”/2U high and 12.7” deep, excluding knobs and connectors), the AMS S-DMX features high-quality components and construction. Its motherboard system with plug-in circuit cards and ribbon cables minimizes maintenance issues, maintaining the high standards of the AMS S-DMX range with advanced programmability, repeatability, and storage capabilities, putting engineers in full control of system functions.
The balanced inputs of the AMS S-DMX are first processed into unbalanced signals by the input cards. These signals undergo low pass filtering to prevent aliasing. Buffered drive signals are then sent to the input level controls on the front panel, which feed preset gain stages on the input cards. The outputs from these stages are directed to the stereo sampler card.
The stereo sampler card in the AMS S-DMX mixes the input and feedback signals into balanced stages to prevent common mode interference. Each channel is processed by a sample and hold device at a 40kHz sampling rate. The output is scaled to optimize the signal-to-noise ratio, generating a two-bit exponent number to track the scaling factor. The card also drives the channel ‘b’ traffic signal LEDs.
Control and timing signals for the stereo sampler card come from the memory control board, with clock inputs from either a crystal oscillator or a voltage-controlled oscillator (VCO). The ADC conversion command triggers the latching of the correct exponent for each sampling period. The sampled analogue output is fed through a buffer amplifier to the ADC, initiating a conversion with the twelve-bit result stored in memory. The ADC card of the AMS S-DMX also generates the VCO, which adjusts the sampling rate.
The memory control card provides timing signals and manages read/write addresses in the RAM array, loaded via ribbon cables from the pitch changers.