Ashly manual Operating Manual - VCM-88, VCM-88E, RD-8, RW-8 Level Controllers, Introduction

Operating Manual - VCM-88, VCM-88E, RD-8, RW-8 Level Controllers

1. Introduction

One of the many useful circuits to be developed for audio use is the VCA, or voltage controlled amplifier. A VCA circuit allows for accurate, low distortion level con- trol without signal degradations encountered when using mechanical controls or long signal paths. VCA circuits can be found in compressor/limiter/expanders, noise gates, noise reduction systems, automatic mixers, VCA-Bus consoles, and other places where remote control or fast automatic system response is required. Designers at Ashly felt there was still a need for high quality VCA control which could be incorporated into professional sound systems without unnecessarily high cost or complication.

The Ashly VCM-88 and the similar VCM-88E (euro-block connector model) provide eight fully-indepen- dent VCA channels in a single unit capable of limiting, re- mote level control, and mixing. When connected to the Ashly RD-8 (desktop) or RW-8 (wall-mount) remote con- troller, direct DC control, or Ashly's Protea System Soft- ware, the VCM-88(E) controls individual channel and mas- ter levels with a range of -75dB to +20dB. Each VCA chan- nel has separate input and output jacks for patching into line-level signal paths, and can be reconfigured to use single connector insertion for patching into mixing consoles. When using the VCM-88(E) as a mixer (using the master output), each channel’s input can be configured to “pass- through” to its output for daisy chaining multiple units to- gether.

The Ashly VCM-88E maintains the features of the VCM-88 while replacing 1/4" jacks with Euroblock con- nectors. It also adds bi-directional data communications, non-volatile memory of level settings, and uses all recessed face panel controls specifically for fixed installations.

The RD-8 remote controller is a compact slidefader remote level controller which can be desk-top situated or rack-mounted into two rack spaces (3.5 inches) using the RD8-RM optional mounting bracket. This remote control- ler is also available as the RW-8 for wallmounting into a standard 4-gang electrical box. The RD-8 controls the au- dio levels of the VCM-88(E) over a standard XLR snake cable or shielded twisted pair. As it is powered entirely by the VCM-88(E), no batteries or remote power supply are necessary for either RD-8 or RW-8. The RD-8 can com- municate to the VCM-88(E) over a 24 gauge snake cable in excess of 1/4 mile (400m). The RD-8 also pulse-shapes the digital waveform to eliminate digital crosstalk noise into adjacent audio channels.

2. Unpacking

As a part of our system of quality control, every Ashly product is carefully inspected before leaving the fac- tory to ensure flawless appearance. After unpacking, please inspect for any physical damage. Save the shipping carton and all packing materials , as they were carefully designed to reduce to minimum the possibility of transportation dam- age should the unit again require packing and shipping. In the event that damage has occurred, immediately notify your dealer so that a written claim to cover the damages can be initiated.

The right to any claim against a public carrier can be forfeited if the carrier is not notified promptly and if the shipping carton and packing materials are not available for inspection by the carrier. Save all packing materials until the claim has been settled.

3. AC Power Requirements

Astandard IEC-320 AC inlet is provided on the rear panel to accept the detachable power cord shipped with the unit. Units distributed within the United States are preselected for 120VAC, 60Hz and should be plugged into a standard NEMA 5-15 3-wire grounded AC receptacle. Most units distributed outside the US are preselected and labeled for 240VAC, 50-60Hz and are shipped with the appropriate power cord.

The VCM-88(E) will perform normally from 100 to 125 volts AC. An internal line fuse is used. In the event of fuse failure, refer to a qualified service technician for servicing. Maximum power consumption of the VCM- 88(E) is 18 watts.

4. Security Covers

For installations where it is desirable to protect the front panel controls from tampering or accidental misadjustment, use the Ashly security cover, which is avail- able in both single and double rack space sizes. Installa- tion is simple and does not require removal of the equip- ment from your rack. See your Ashly dealer for details.

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