Ashly XR1001, XR2001, XR4001 manual Output Level, Clip Indicator

Operating Manual - XR1001, XR2001, and XR4001 Electronic Crossovers

The purpose of this control is to help offset the inaccuracies inherent in typical loudspeakers, thereby helping you to achieve a flat system response. If you use a spectrum analyzer to set up your system, adjust the re- sponse control to obtain the flattest response through the crossover region before any equalization is applied to the system. If adjusting by ear, we recommend an initial set- ting of 6dB. Adjust from this point if the system appears to have an excess or deficiency of level at the crossover point.

NOTE: The Response control is not a “slope” control. A 12dB/octave crossover will always have a slope of 12dB/octave regardless of the setting of this control. Likewise, a 24dB/octave crossover will always have a slope of 24dB/octave. The Response control only affects filter response shape in the immediate vicinity of the cross- over frequency; the ultimate crossover slope is a fixed parameter.

5.5Output Level

The crossover’s output stage operates at unity gain with the output level controls set at “U”. Max gain of the output stage is +15dB. In a typical setup, power amplifier input level controls should be run “full-on”, with level control being accomplished at the crossover. Adjust the crossover level controls for best system balance. Keep

in mind that in any multi-amplified system, the higher fre- quency speakers tend to be more efficient. Expect to run the higher frequency level controls at a somewhat lower setting than the low frequency level controls to obtain proper frequency response. Note that horn and compres- sion driver combinations are much more efficient than cone speakers, often by 12 to 20dB! When cones and compres- sion drivers are used together, you should expect a much lower level setting for the horns (all other factors being equal) to compensate for this difference and obtain proper balance.

Output Mute switches allow you to isolate indi- vidual or grouped outputs for listening tests without af- fecting the settings of any other outputs.

5.6Clip Indicator

Ashly crossovers feature a peak detection circuit which monitors signal level at several critical points in the crossover: input, filters, and outputs. The LED will flash when signal levels of +20dBu are reached anywhere in the crossover. Since our crossovers have a nominal 23dB of headroom referenced to a standard operating level of 0dBu (.77 Volts), a flashing LED warns you that you are only 3dB from clipping.

Since peak levels are monitored at several key circuit points, the clip LED can be used to isolate the source of any overload. If the LED flashes even though all input and output levels are turned down, the signal being fed to the crossover is excessive. If the LED flashes when you turn the Input level control up (with the out- puts still turned down), the overload is occurring in the filter sections, and you should back the Input level down a bit. If the LED first flashes when you turn the output level controls up, then the overload is occurring in the output stage. In this case, if your power amplifier con- trols are at full gain, you are probably severely overdriving your amplifier.

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