EAR 822Q

The EAR 822Q Pultec type equalizer has been designed to be highly flexible and thus useful in a wide range of applications. Passive equalization networks combined with valve input and output buffers are used in order to minimize disturbing side effects such as phase shift and ringing. The audio circuitry conforms to the EAR principles of simplicity and subjective "transparency", with low distortion at all normal signal levels. A "clickless" bypass switch allows easy comparison between the processed and direct paths. Variations in response include low pass, high pass, band pass and high or low frequency shelf with variable Q and turnover frequency.


The recent trend towards ever-more-complicated equalizers and filters has not resulted in any real increase in flexibility, and certainly not in quality.

The EAR 822Q "Pultec"-type equalizer is a relatively simple passive device that has been designed to be highly flexible and therefore genuinely useful in any application. As always with EAR products, the highest possible sound quality is of the essence, and the filter circuits are used so as to introduce the minimum possible of disturbing side effects in the way of phase shift and ringing, thus preserving the essential qualities of the signal intact.

It is a characteristic of this device that subtle equalization changes are not masked in effect by the distortion often due to inadequate active filters. Variations in response include low pass, high pass, band pass and high or low frequency shelf, with variable Q and turnover frequency.


EAR 822Q Single Channel Passive Pultec Type Valve Equalizer Features :

• Operation - Passive equaliser with balanced valve output
• Low boost & cut frequencies - 20, 30, 60, 100Hz; 0, +14, - 18dB variable
• High boost frequencies - 3k, 5k, 7k, 10k, 12kHz; 0, +18dB variable
• Maximum output level (1% distortion) - +25dBm
• Input and output impedance - 600 ohm nominal, balanced and floating
• High cut frequencies - 6k, 10k, 20kHz; shelf 0, - 18dB variable
• Bypass switch - no level change, clickless
• Operation - Passive equaliser with balanced valve output

Alternatively, the EAR 823MQ is a variant of the 882Q designed for use in the midband. It is slightly simpler, with the frequencies set closer together in order to give more precise control over this critical spectrum.