1. Function Introduction:

By blocking the formation of acoustic feedback through frequency shifting, it effectively prevents whistling caused by acoustic feedback in on-site sound reinforcement situations.

It can significantly increase the pickup distance of the microphone, increase the volume of the microphone, and improve the sound transmission gain.

The frequency response after frequency shift will not change, and the sound will still be full and powerful, without any dry sound or limited bandwidth.

It can effectively protect the downstream equipment and prevent damage to the amplifier and speaker caused by sound feedback.

There are two frequency shifting methods available: up frequency shifting and down frequency shifting, which can be flexibly selected based on actual acoustic feedback and can effectively cope with harsh usage environments.

The frequency shift frequency can be adjusted to 8 levels, which are 2.5/3.0/3.5/4.0/4.5/5.0/5.5/6.0Hz. Each level corresponds to a touch switch button on the front panel, making the operation very intuitive and convenient.

■ On the front panel, two digit Nixie tube displays the frequency of the current frequency shift in digital form. And accompanied by LED flashing display.

The front panel 8-segment code removal switch can be set to save the default frequency shift after startup, which is completely suitable for occasions without professional personnel on duty. Once set, there is no worries about the future.

The rear panel has four audio inputs and four audio outputs (two balanced and two unbalanced), and can also be used as a 4-way mixer.

2. Technical parameters:

Frequency shift frequency: 2.5/3.0/3.5/4.0/4.5/5.0/5.5/6.0Hz, with a total of 8 gears and a frequency error of less than 5%

Frequency shift method: up shift and down shift

■ Frequency shift frequency display: two red Nixie tube

Operation method: Touch lightly (frequency shift frequency is preset to use a dial switch)

Frequency shift frequency startup preset: 2.5/3.0/3.5/4.0/4.5/5.0/5.0/5.5/6.0, a total of 8 gears, dial switch setting, unit Hz

Balanced input impedance: high resistance 22K Ω, low resistance 12K Ω, @ 1KHz/± 10% Note: Please refer to 5.3 on page 9

Balanced input level: maximum+15dBu (input set to high resistance); Maximum+24dBu (input set to low resistance)

Balanced output impedance: 500 Ω/± 10%

Balanced output impedance: maximum+10dBu, load 10K Ω

Balanced output level: maximum+10dBu, load 10K Ω

Unbalanced input impedance: 50K Ω, @ 1KHz/± 10%

Unbalanced input level: maximum+12dBu

Unbalanced output impedance: single output 2K Ω, dual output 4K Ω, @ 1KHz/± 10%

Unbalanced output level: maximum+18dBu, load 10K Ω

Frequency response: straight through 20Hz? 20KHz, ± 1.2dB (0dBu input, output load 10K Ω)

Frequency shift of 20Hz? 20KHz, ± 1.8dB (0dBu input, output load 10K Ω)

Signal to noise ratio: direct 91dB (0dBu input, output load 10K Ω, A-weighted, 20Hz? 20KHz)

Frequency shift 85dB (0dBu input, output load 10K Ω, A-weighted, 20Hz? 20KHz)

■ Total harmonic distortion: pass through 0.07% (0dBu input, output load 10K Ω)

Gain: Balanced high impedance input is about -2.5dB, balanced low impedance input is about -13dB, unbalanced input is about -0.5dB, and load capacity is 10K Ω

Usage environment: temperature 0 ° C? 50 ° C, relative humidity 30%? 80%, altitude less than 3000 meters

Power specification: 220VAC ± 10% 50/60Hz

Specification of safety tube: 250VT0.5A

External dimensions: 430 × one hundred and eighty × 44mm (excluding rack), 485 × one hundred and eighty × 44mm (including rack)

Weight: approximately 2kg,

Test conditions: temperature 25 ° C ± 2 ° C, relative humidity 55%? 65%, 220VAC/50Hz, 30 minutes after startup