QA470 Low Noise Mic Pre-amp [Retired]

NOTE: The QA470 has been replaced by the QA471, which is the same product with 10 dB of mic gain instead of 20 dB. There were many cases where mics with high acoustic overload points (AOPs) were requiring the attenuator to be engaged on the QA401 at 125 to 130 dBSPL. The lower gain will help with that. Since the QA401 input noise floor is -115 dBV (20 kHz, no weighting), there's still plenty of margin to measure the at the noise floor even with just 10 dB of gain. The QA471 will be begin shipping the week of September 14. The QA470 is a low-noise, fixed gain (20 dB ± 0.2 dB typical) microphone amplifier, with a switchable +48V phantom supply. The QA470 also features two general purpose amplifiers (with 30 and 10 dB of gain) based on ultra-low-noise OPA1612 opamps and powered from split ±12V rails, with nearly 18 dBV = 8 Vrms of signal output. The amplifiers inputs are AC coupled and can withstand up to 50V of DC, making them the perfect choice for measuring the noise on DC power suppli