YORKVILLE POWERMAX 1622 SERIES 2 Скачать руководство пользователя

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7. HPF Button

Situated at the top of the mono channel strips, this switch activates a High-Pass Filter

(a bass roll-off of 18 dB per octave below 80 Hz). The stereo channels do not have this

feature, as they are normally used for pre-recorded material.

The HPF (High-Pass Filter) is useful for controlling unwanted low-frequency spillover

picked up by microphones located too close to the bass drum, bass amp or the key-

board amp. It is also effective in regulating acoustic guitar pickups that are sounding

too boomy (the lowest note on a concert-tuned guitar is 81.2 Hz, so you aren’t losing

anything by rolling off the input response below 80 Hz). Additionally, the HPF works

to reduce pops and thumps from vocal microphones. Any microphone, or pickup, which

reflects a source that does not go below 80 Hz should have the HPF activated. This

includes most wind instruments, most male voices, nearly all female voices and all drum

microphones except for the kick-drum.

Why roll off the bass on these channels? …because you will obtain better clarity and

improve the system’s gain before feedback.

8. Gain Control

PowerMAX features active input circuitry with exceptionally high headroom. The Gain

control regulates the channel gain level to match it with the input signal strength. There

are two gradation circles, the outer one (-20 dB to +56 dB) for the Mic input, the inner

one (-36 dB to +40 dB) for the Bal Line input. Since this control has a range of 70 dB, it

presents the user with considerable variability given the slightest amount of movement.

A quick way to ensure that the Gain is adjusted correctly is to turn it up during a

sound check until the Clip LED begins to flash (keep the channel fader at a safe, low set-

ting during this process), then turn the Gain down slightly. PowerMAX’s Clip LED drive cir-

cuits are preset to fire at 6 dB below the onset of actual clipping so you need not worry

about seeing some activity on the lights. You will find that this or any system performs

more cleanly and quietly with the Gain controls all set properly. Also, you may use PFL

(Pre-Fade Listen) and the VU meter to set 0 dB.

9. Channel EQ

The mono channels feature 3-band Equalization with control of +/-15dB. Mids are swept

from 80 Hz to 8 kHz (2.5 kHz highlighted in the graphics as (our) standard mid frequen-

cy). The High EQ is shelving at 12 kHz and Low EQ shelves at 80 Hz. The stereo channel

EQ is 4-band (+/-15dB) with fixed mids at 250 Hz and 2.5 kHz. The Low EQ control (+/-

15dB) are the same as the mono channels.

Setting the channel EQ, like setting the Gain, is best done during a sound check. In

this case however, the less you vary things above or below “0,” the better. +/-15dB rep-

resents considerable level change. If you need to turn down the High EQ on a channel,

perhaps due to a persistent feedback problem with that microphone, you may need to re-

adjust the level fader. In any case, big boosts are probably best avoided.

One cure for a bad feedback problem is to Insert (see Insert Jack) a graphic or

parametric EQ into the problem channel and adjust it to attenuate only the feedback

frequency. That way, fewer innocent frequencies will be affected. However, the chan-

nel EQ’s Mid Sweep control can often be used quite effectively to perform a similar

function. Simply set the Mid at about -6 dB then rotate the Sweep control until the

feedback stops. Now turn the Mid up slightly to normalize the frequency response as

much as possible without feedback.

10. Mon 1 and Mon 2 Sends

These are pre-fade, post-EQ sends. Internal routing is…
  1.  to the Mon masters and Solo buttons
  2.  to the Mon 1 and 2 EQs
  3.  to the Mon 1 and 2 Line Level Outputs
  4.  through the cutoff switches in the Amp C and D Amplifier Inputs
  5.  to the built-in, 800-Watt amplifiers C&D and finally
  6.  to the Mon 1 and 2 Power Amplifier Outputs.

Post-F

ader

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