Behringer DSP8024 user manual The FEEDBACK DESTROYER

ULTRA-CURVE PRO DSP8024

When the limiter threshold is exceeded, the indication LIM will appear in the level meter display to indicate that the limiter is attenuating the output.

With softkey A you leave the level meter, and return to the main EQ window.

With softkey B you erase the maximum levels from the memory.

With softkey C / you switch the display from the ULTRA-CURVE PRO input and output.

With key D you can choose between three different tables of reference levels. The 0 dB point is indicated by a bold

marker, while at the same time, the numerical display changes. refers to the digital peak level. This level may not—under any circumstances—be exceeded! This will result in a very noticeable form of distortion, which occurs much faster, and sounds very much more unpleasant, than the familiar distortion associated with analog devices. refers to the operating level found in professional audio equipment (analog inputs and outputs of the

ULTRA-CURVE PRO). refers to the operating level found in homerecording and domestic audio equipment, a typical example being tape recorders with RCA connectors. When setting the ULTRA-CURVE PRO internal level, or when using the optional AES/EBU interface, the peak level display of the DIG MAX scale is the only one to use. The +4 dBu and -10 dBV scales serve to monitor the analog inputs and outputs of the ULTRA-CURVE PRO.

Please note that the RMS level will usually be quoted in the technical specifications of analog devices for example, for the input sensitivity of power amplifiers. The effective level always lies below the peak level.

+The difference between them depends on the signal characteristics for a static sine wave, the effective level is about 3 dB below the peak level. For a dynamic signal the difference is in the region of 8 dB.

The DIG MAX level is, of course, related to the analog input and output levels, as 0 dB DIG MAX corresponds to the maximum output level of the ULTRA-CURVE PRO. The following example, using a sine wave at maximum amplitude, clearly illustrates the relationship between the various scales:

Scale		Reading
	RMS		PEAK
DIGMAX	-3 dB		0 dB
+4 dBu	+6 dB		+12 dB
-10 dBV	+21 dB		+24 dB
Maximum level:		+16 dBu

Tab. 2.1: Level meter scale correlation

As can be seen from the above table, the ULTRA-CURVE PROs maximum analog output level is +16 dBu, or +14 dBV.

The ULTRA-CURVE PROs analog inputs can handle signals of up to +21 dBu, but it is important to remember that, in case of such high input levels, the digital limiter may operate if the level in the equalizer is not appropriately lowered. Please refer to the operation of the digital limiter explained in section 2.1.6.

2.1.3 The FEEDBACK DESTROYER

By pressing softkey B you leave the main EQ window and go into the FEEDBACK DESTROYER menu.

Fig. 2.4: FEEDBACK DESTROYER menu

The display will show the current settings for all six of the ULTRA-CURVE PRO parametric equalizers (selected frequency, bandwidth and degree of boost or attenuation). Additionally it will show whether the parameters are fixed (PAR), or are set for automatic search, to function as the FEEDBACK DESTROYER (AUT or SGL). Auto

10 2. OPERATION