TOA E1231

The TOA E1231 is a single-channel, 28-band, one-third octave equalizer, designed to provide clean and accurate audio equalization for permanent installations. The E1231 provides 12dB of boost or cut at each of its 28 frequencies, all of which are centered at ISO 1/3 octave increments from 31.5Hz to 16kHz. The E1231 comes with active bandpass/bandreject filters that are designed for minimum phase shift. Slide controls feature a precision-calibrated linear scale, noiseless operation, and center detents for easy and accurate adjustment. Filters are summed in parallel for reliability, so that the failure of one filter does not interrupt operation of the others. Continuously variable high-pass and low-pass filter can be set for either a 6dB or 12dB per octave slope and is variable from 15Hz to 300Hz. A Filter In/Out switch with an LED status indicator allows the user to bypass the high- and low-pass filters. In addition to an EQ In/Out switch, an automatic EQ bypass function provides complete signal bypass of the unit in the event of an AC power loss. An output muting function suppresses turn-on/turn-off transients. The input level control gives +/-12dB of adjustment to allow for a wide variety of input levels/sources. An LED indicator monitors both input and output levels and illuminates when either comes within 3dB of clipping. The input and output are electronically balanced and utilize terminal strip connectors. High quality, low distortion input and output transformers, providing 30Hz - 20kHz response (+/-0.15dB) are optional and installation requires no soldering.

A security cover is included with the E1231 to guard against disturbance or tampering. The E1231 occupies two standard EIA rack spaces.

Features

• 28 filters on ISO 1/3 octave center frequencies from 31.5Hz to 16kHz
• Continuously variable 12dB boost or cut at each center frequency
• High quality, minimum phase shift active filters
• Noiseless center-detent slide controls with precision-calibrated linear scales
• Continuously variable highpass and lowpass fitlers with wide control ranges and a Filter In/Out switch
• Low-pass filter can be set for either 6dB/oct or 12dB/oct
• EQ In/Out swith for manually bypassing equalizer
• Automatic EQ bypass circuitry in case of AC power loss
• LED peak indicator monitors input and output levels, for proper gain structuring
• Variable input level control allows a variety of input levels and sources
• Optional input and output isolation transformers
• Security cover is included