The
Presonus ADL 700 All Tube Channel Strip Mic Preamp incorporates a single-channel version of the award-winning PreSonus ADL 600 two-channel tube preamplifier, which was codesigned with famed tube-circuit designer Anthony DeMaria. PreSonus and DeMaria teamed up to create a distinctive Class A, discrete design that employs one 12AT7 and two 6922 vacuum tubes per channel, operating with ±300V power rails for maximum headroom and superb tone. The dual-transformer design ensures low-noise operation, with maximum common-mode rejection. This results in an ultra-low-noise tube preamp with a big, warm, smooth, clear, distinctive sound.
Among the hallmark features of ADL series preamps is an Input Source Select switch with variable mic-input impedance. This switch enables you to choose among signal sources and patches the selected input through the signal chain, completely bypassing the other two inputs. It also provides a choice of four mic-input impedances: 1500Ω, 900Ω, 300Ω, and 150Ω. Lowering or raising the ADL 700 mic-input impedance can create subtle coloring and filtering effects, enabling you to get a wider variety of tonalities without using the EQ.
The ADL 700’s FET-based compressor and semi-parametric EQ were custom-designed by Robert Creel, the mastermind behind many of PreSonus’ most beloved analog circuits, including the XMAX preamp. FET (Field-Effect Transistor) compressors use transistors to emulate a triode-tube sound. This type of compressor generally provides a faster attack time and better repeatability than the optical compressors that are more commonly found in channel strips in this price class.
The ADL 700 compressor features include fully variable attack, release, threshold, ratio, makeup gain, and bypass. When Threshold is turned fully counterclockwise to the ST position, the onboard compressor controls are bypassed, and compression is controlled externally via a Stereo Link connection to a second ADL 700.
Of course, the preamp offers 48V phantom power, polarity reverse, and a -20 dB pad. In addition, it provides variable mic-input gain, employing an 8-position rotary switch that provides 35 dB of gain in 5 dB increments. A Trim potentiometer (±30 dB) allows you to make fine adjustments to the final preamp stage of the ADL 700 input.
You also get a -12 dB/octave high-pass filter whose frequency threshold can be set at 20 Hz, 40 Hz, 80 Hz, or 200 Hz, or it can be turned off completely.
The ADL 700’s FET-based compressor and semi-parametric EQ were custom-designed by Robert Creel, the mastermind behind many of PreSonus’ most beloved analog circuits, including the XMAX™ preamp. FET (Field-Effect Transistor) compressors use transistors to emulate a triode-tube sound. This type of compressor generally provides a faster attack time and better repeatability than the optical compressors that are more commonly found in channel strips in this price class.
The ADL 700 compressor features include fully variable attack, release, threshold, ratio, makeup gain, and bypass. When Threshold is turned fully counterclockwise to the ST position, the onboard compressor controls are bypassed, and compression is controlled externally via a Stereo Link connection to a second ADL 700.
The 4-band semi-parametric EQ was designed with musicality in mind, combining isolated filters and optimized, per-band Q to provide subtler signal shaping without harsh artifacts. All bands have Gain (±16 dB) and Frequency controls, with overlapping frequency ranges and fixed Q (0.6). The low and high bands are switchable between shelving and peak.
Dual-mode analog VU metering enables monitoring of output and gain-reduction levels. A -6 dB switch offsets the meter for use with hot source signals. A master level control adjusts the overall output from -80 to +6 dB.
With its extensive feature set, ultra-low noise (-100 dB S/N ratio), >73 dB gain, extended frequency response of 10 Hz to 45 kHz, and top-of-the-line sound, the ADL 700 is a superb creative tool for serious recording engineers and musicians.