The Model 7622 Dual Microphone Preamplifier is based on designs that have stood the test of time and has been built with the budget conscious in mind. This unit is made with 100% discrete components, hand wound transformers and was fabricated to precisely match vintage counterparts manufactured in the early to mid 70’s. It has been designed to complement the Model 7602 Preamplifier / Equalizer for those who desire two channels of preamplification in the same size chassis, but do not need external equalization.

Model 7622 Features

• Fully balanced transformer mic and line inputs
• Balanced XLR outputs
• Hi-Z direct inputs for instruments on the front panel
• 48VDC phantom power selectors on the front panel
• 180 degree phase reversal switches on the front panel
• 20 position gold contact ELMA rotary gain switch for both Mic and Line sections
• Output level controls function as faders when going straight to tape
• Oversize power supply provides many times the current needed for optimum sound quality
• One-year warranty

Electronics

By employing classic circuit design, polystyrene capacitors, a gold contact ELMA gain selector and custom wound transformers, Chameleon Labs ensures that the Model 7622 will exhibit classic audio sound.

The Model 7622 has a transformer balanced input with a range between 20dB and 80 dB of gain. The separate line input is transformer balanced and accepts input levels from -20 to +10dB.

The CPS-1 (included) is a 1U rack mountable, regulated, toroidal power supply for the 7622 and is required for operation of the unit.

Model 7622 Specifications

Input impedance:          Microphone – 1,200 ohms
                                   Line – 10,000 ohms
                                   D.I. – 100,000 ohms

Sensitivity:                   Microphone – -80dBm to -20 dBm in 5dB steps for 0 dBm output.
                                   Line – -20 dBm to +10 dBm in 5 dB steps for 0 dBm output.

Noise:                          Measured at 80 db of gain with 200 ohm input termination, without 20Hz to 20kHz to assist in filtering out noise.
                                   -49dbu with final output stage at 50% EIN -129 dbu;
                                   -46dbu with final output stage at unity EIN -126 dbu;
                                   -56dbu without final output stage EIN -136 dbu.

Output:                        Balanced and floating to feed a 600 ohm load.
                                   Maximum output +26 dBm into 600 ohms, or +20dBm into 150 ohms.

Output impedance:        600 ohms, balanced (source impedance 75 ohms).

Frequency Response:    11 Hz – 77.65 kHz – 3 dB.
                                   Level variation is less than 0.2%.

Distortion:                    1kHz = 0.0245%