Gilderfluke & Co. has offered digital solid state audio repeater cards for well over 20 years. Many of their audio cards have landed in theme parks and museums around the world. Some of their early audio cards and bricks include the 8-bit DR-50, DR-100, DR-300, DR-400, DAS-100, CC-3250, AB-50, and AB-100. Their early 16-bit audio repeater cards include the AB-3000 and DR-3000. These early cards used EPROM chips that required a separate progrmmer to record the sounds.

More recently, Gilderfluke released their MP3-50 cards which play .WAV or .MP3 encoded audio files saved to compact Flash media cards. This eliminated the need for an expensive EPROM burner and added more capacity since the media size is larger. The MP3-50 line also included the MP3-50/8 and MP3-50/40, which added show control to the audio, providing a complete solution for small shows or single animatronic figures. Gilderfluke has updated the MP3-50 line to the SD-50 cards to support cheaper SD media. They have also added the inexpensive SD-10 and SD-25 audio repeaters. The SD-10 stores audio tracks on SD media and has trigger inputs, but no access to specific sound files, show control, or amplifier. The SD-25 audio repeater adds more input control and a Class D audio amplifer.

SD-10 Audio Repeater

The Sd-10 is Gilderfluke's entry-level sound controller. The Sd-10 audio repeater is an amazing little device for the cost. Files are stored on a full-size secure digital (SD) flash memory card as .MP3 or .WAV audio files. RCA line out plugs supply audio out for the show. There is left and right audio out so the sounds can be set up as stereo tracks or two mono audio tracks. A separate amplifier is needed to boost the output signal. If two audio tracks (mono) are used, then two separate amplifiers may be needed. The SD-10 has 3 optically isolated trigger inputs. The inputs are electronically controlled, not push buttons. The input controls are similar to a CD player. They control play/pause of the audio track, play next or previous audio track, and increase/decrease the output volume.

SD-25

The Sd-25 is a step up from the Sd-10. It will do everything a Sd-10 will do, and more. The Sd-25 includes a Class D amplifier with 20 watts per channel (2 channels). The built-in amplifier has at least a 90% power efficiency and distortion less than 0.1%. This is important, particularly for mobile shows or shows that run off of limited power supplies like solar power.

SD-50

The SD-50 line is Gilderfluke's top of the line audio repeater card. It comes in two version including the SD-50/8 and the SD-50/40. The SD-50 includes all the features of a Sd-25, but also adds show control and improved access to sound files from the Gilderfluke PC-MACS software. It features DMX-512 input and output, MIDI trigger inputs, the ability to add GPS, and an Atomic clock option for long-term show scheduling, automated clocks, chimes or bells. The SD-50/8 has 8 digital outputs for controlling relays or switches. The SD-50/40 has 40 digital outputs for controlling relays or switches.