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Controls: Front panel

 

· +48 V

Switches phantom power on and off at the Mic input connector. Internal provision is made for other voltages by changing a zener diode. Contact the manufacturer for details. Always switch the phantom power off when it is not needed as it can damage single ended signal sources. The internal build out resistors of 6k8 provide for the IEC recommended current limiting, but do not provide adequate protection against idiocy.

· Input Selector

Switches between the mic and line inputs as well as establishing the gain structure for the unit. The extremely wide dynamic range is in part made possible by the judicious use of gain setting relays that allow us to manipulate the gain structure by modification of the gain stages and internal attenuation.

· Input overload LED

This LED lights when the output of either the first or second stage exceed +34 dbv.  ccasional lighting still allows an additional 6 db of headroom!

· Insert Bypass

Provided at the rear panel is the output of the preamp and the input to the gain cell. These signals isolated from the main signal path with high voltage op-amps. When the insert points are not being used, we do not want to degrade the purity of the audio path with any solid state devices so we sense the insertion of a jack in either the insert send or return

connector. When the system is hard wired into an installation, such as a rack in a control room, we wanted to offer the provision of bypassing the insert silicon from the front panel. When there is no jack inserted in the inserts, the signal is automatically bypassed, and the front panel switch provides no function.

· Input trim

This control provides ± 5 db of trim for the front end gain. Used in conjunction with the input selector, you set the input level to read

approximately "0" on the Audio Meter, and then establish your threshold setting.

· Phase reverse

Provides for 180" shift of both the Mic and Line Inputs. The Phase Reverse switch point is post insertion and Pre gain cell.

· Meter zero

Trim pot for setting the "0" Gain Reduction meter position. This is done by removing all signals from the unit, and adjusting until the

meter is at "0"

 

 

· Limiter Tip In

Because the Mu of the tubes employed in the manufacture of the device vary significantly, we must provide for adjustment of the gain cell  transconductance point.  Adjustment of the unit is accomplished as follows;

1. Feed in a steady tone of any amplitude.

2. Adjust the input selector and trim so the

input meter reads "0"

3. Depress the "Gain reduction Bypass" switch

4. Select Output metering on the Audio Meter

5. Adjust the output trim so that the Audio LED meter reads "0"(Yellow LED is lit)

6. Set the threshold control to fully Clockwise.

7. Insert the gain reduction by depressing

the gain reduction bypass switch.

8. Adjust the Gain Cell Tip in so that the audio

remains at "0" and does not change level

· Input meter select

This switch determines the source for the Audio Metering. When depressed, metering

of the input gain stage is accomplished, and when it is out the meter is looking at the output of the unit as it feeds the outside world. "0" is equal to +4 dbu

· Gain Reduction bypass

This switch hard bypasses the gain cell by completely cutting it off. This is accomplished by driving the cathode to >6 volts above the

grid, (Clamped by zener diode).

· Preset/Manual

5 presets are provided for your ease of use and listening enjoyment. The Presets on the top of the selector switch provide an alternate setting to each of them to allow you to trim the values of attack, release and ratio. The bottom settings bypass the front panel adjustment. (The threshold is always available

for your amusement.) Additional presets are available from the manufacturer on plug in cards in the PCMCIA size format. Custom presets are available as well. Contact your dealer for details.

· Threshold

The point the limiting is initiated is set with this large and sexy control. The range of limiting is adjustable from -40 to +20 ref. +4

· Gain Cell Clip

The clip LED indicates that maximum attenuation of the gain cell has been reached.

This indicates when the amount of requested gain control requires that the transconductance cell act as a diode. This sounds really shitty, so we warn you when

it is about to happen. If this light is blinking, you're a dumb fuck and shouldn't be

allowed near a tool as powerful as this in the first place. [ALT WORDING ED]Operating the unit with this indicator lit will result in distorted sound. So avoid operating at these signal

levels unless colored sound is desired.