Model 750

Record/Talk Back External Audio Input

The Model 750 contains an internal micro- phone which is used by the setup section for voice recording, as well as by the talk back functions. In special cases it may be desirable for an external source of audio to be used in its place. A ¼-inch 3-con- ductor phone jack allows the connection of a line-level signal, with a nominal level range of –20 to +4dBu.

Prepare the mating connector (plug) so that tip is signal high (+ or hot), ring is low (– or cold), and sleeve is shield. With an unbalanced source connect the tip to high (+ or hot), and both the ring and sleeve to shield. If connecting to an unbalanced source in this manner results in hum or

Figure 4. Detail of back panel showing voltage configuration chart

noise, connect tip to high (+ or hot) and ring to shield; leave the sleeve unterminated.

It is intended that a microphone associ- ated with an intercom system headset will serve as the external audio source. Inter- com station’s often provide an amplified, line-level version of the mic signal. It is often referred to as a “hot microphone” output.

A trim potentiometer is associated with the external audio input, allowing adjustment of the input sensitivity. Refer to the Con- figuration section of this guide for details. Information is also provided on how to set the front panel DIP switch to select the external audio input.

Connecting AC Mains Power

The Model 750 is factory configured to operate from AC mains power of either 100, 120, or 220/240V, 50/60Hz. In most cases, units shipped to North America are factory configured for 120V operation and are supplied with an internal 0.5A,

5 x 20mm fast-acting fuse. Units config- ured for 100V also utilize a 0.5A fuse. Units configured for 220/240V operation are supplied with a 0.25A, 5 x 20mm fast- acting fuse.

Before connecting the Model 750 to mains power, determine the actual mains voltage and confirm that the Model 750 has been configured correctly. As could be ex- pected, an incorrect mains configuration could seriously damage the unit.

Should it be necessary to change the unit’s operating voltage refer to the Ser- vice Guide, a separate document available upon request from Studio Technologies.

Model 750 User Guide

Issue 3, May 1997

Studio Technologies, Inc.

Page 15

Page 12
Image 12
Fostex 750 manual Record/Talk Back External Audio Input, Connecting AC Mains Power

750 specifications

The Fostex 750 is a premium closed-back headphone that has garnered attention for its combination of advanced technology, comfort, and sound fidelity. Designed primarily for studio applications, the Fostex 750 delivers an exceptional listening experience that caters to both professionals and audiophiles alike.

One of the main features of the Fostex 750 is its dynamic driver technology. The headphones are equipped with large 50mm titanium-coated drivers that provide a powerful and clear sound reproduction. This driver configuration is engineered to deliver a wide frequency response, ranging from deep bass to sparkling highs, ensuring that every detail of the audio is captured. With an impedance of 25 Ohms, the headphones are highly efficient and can be easily driven by a variety of devices, including portable music players and digital audio converters.

Comfort is another highlight of the Fostex 750. The headphones feature plush ear pads made from soft polyurethane, which provide excellent cushioning for extended listening sessions. The adjustable headband offers a customizable fit, allowing users to achieve an optimal acoustic seal that enhances sound isolation. This is particularly beneficial in studio environments, where external noise can interfere with critical listening.

In terms of build quality, the Fostex 750 boasts a robust yet lightweight design. The combination of high-quality plastics and metal components contributes to its durability, while the foldable structure makes it portable and convenient for travel. This practicality is further enhanced by the detachable cable, which allows for easy replacement in case of wear.

Another notable technology integrated into the Fostex 750 is the use of new acoustic engineering principles. These headphones feature a closed-back design that minimizes sound leakage and provides an immersive listening experience. This design is complemented by the innovative bass reflex system, which enhances low-end response without compromising clarity in other frequency ranges.

Overall, the Fostex 750 is an impressive headphone that combines advanced sound technology, comfort, and durability. Its dynamic drivers, ergonomic design, and acoustic engineering make it an ideal choice for both professional monitoring and casual listening. Whether you are mixing in a studio or enjoying music on the go, the Fostex 750 delivers an unmatched audio experience that is sure to satisfy even the most discerning listeners.