Aphex 1100 Mic Preamp Announced

October 4, 1999 -- Aphex Systems Ltd. has introduced the model 1100 Discrete Class A Microphone Tube Preamplifier. Offering the lowest noise possible, 24-bit 96 kHz digital outputs and Aphex’s exclusive MicLim protection circuit, the dual channel 1100 is designed for professional recording, broadcast and production in the digital or analog domains.

Aphex innovations and patents allow the 1100 to deliver an EIN specification of -135dB. The MicLim circuit adds an additional 20dB of headroom, making it virtually impossible to overload the preamp. Since the A/D converter is scaled to clip at the same point as the mic preamp, the digital conversion will be at the highest possible resolution without overload. Aphex’s patented tube circuitry provides the open, present, real and warm sound.

“Our goal with the 1100 is to offer a mic preamp which fulfills all the specifications of a world-class preamp, but goes beyond this in terms of sonic performance and features,” stated Aphex founder and president Marvin Caesar. “The 1100 exhibits clearly superlative features, specifications and performance that are unsurpassed by any preamp today.”

The 1100’s EIN specification of -135dB is as much as 10dB better than some of the esoteric preamps on the market. An additional 20dB of headroom is available due to two Aphex innovations. First, the exclusive MicLim intelligently detects and limits the microphone signal prior to preamplification to prevent clipping. Second, the exclusive low frequency cancellation filter (LoCaf) allows up to 20dB of low frequency cut without using any headroom or triggering MicLim. The filter is tunable in 11 steps from 30 to 195 Hz.

Full featured AES/EBU digital audio output is standard on the 1100. Clock synchronization options allow locking to standard “word clock” and to AES/EBU clock received via back panel BNC input. The internal clock may be set at 44.1, 48, or 96kHz sample rates. When set for external clock reference, the BNC input jack directly links to the BNC output for easy daisy-chaining of multiple 1100s. All digital audio settings are controlled and displayed on the front panel.

Aphex’s patented A/D converter in the 1100 eliminates the need for a high pass filter in the digital domain, which all other A/D converters require. Since the A/D converter is integrated into the system, input to the converter is scaled to be at the maximum output of a particular gain stage. Therefore the input will never create a digital overload. In essence, the MicLim assures that the mic preamp will not be overloaded and the A/D Converter is internally optimized, so the digital output can never be overloaded.

Other features include an all discrete Class A PNP first stage and the patented Reflected Plate Amplifier (RPA) tube circuitry in the second stage and in the output stage. These circuits provide the 1100 with unique sonic characteristics while maintaining low noise and high common mode rejection.

Each channel has a tunable low cut filter (30-195 Hz), tunable gain from 21 to 65 dB and multi-turn output trim. Both channels have individual switches for 20 dB pad, polarity, test tone, phantom power on/off, mute, MicLim, Clock Source (Internal at 44.1, 48 or 96 kHz and External). The headroom meter is a 20 segment LED. The back panel includes (for each channel) XLR In, XLR balanced Out, 1/4" balanced Output, AES/EBU Out (XLR), Word Clock In/Out (BNC), remote mute control jack. The 1100 has an internal linear power supply which is easily switchable to any mains voltage.

The Aphex 1100 Discrete Class A Microphone Tube Preamplifier will be available Winter 1999/2000 with a US Suggested Retail Price of $1995.

For more information, visit the Aphex web site at www.aphex.com.