The ISA One microphone preamplifier delivers Focusrite's prestigious ISA transformer-based preamp in a rugged and portable chassis, at a groundbreaking price. ISA One features the classic vintage microphone preamplifier topology from the original ISA110 module, which formed the cornerstone of each channel of Focusrite's legendary Forté console. The preamp is complemented by a line input and an independent D.I. channel, complete with dedicated gain control, active or passive impedance switch, a TRS Jack output for routing to an amp and an independent XLR output on the rear.
This flexible independent D.I. makes the ISA One ideal both for engineers wishing to blend a D.I.’d guitar signal with a mic’d guitar cabinet, and for demanding performers who require a single classic solution for both guitar and vocals.
A variable impedance circuit has been added, allowing the user to switch between four carefully selected input impedance settings. In addition to the original ISA110 impedance, three further impedance settings allow perfect matching, or creative mismatching of the preamp with any microphone. ISA One also features an insert point, should the need arise to place extra processing between the preamp or D.I. and the optional converter. Phantom power, phase reverse and a 75Hz, 18dB/octave high-pass filter are also available from the angled front fascia.
Independent input metering for both channels is provided in the form of a moving coil VU meter with variable calibration to suit analogue and digital recording media, alongside two six-LED peak meters; inputs can be metered either pre- or post-insert. The meter calibrations utilise all the same reference points as Avid's Pro Tools HD system, allowing effortless line-up.
ISA One’s headphone output features a dedicated volume control, which delivers an external stereo cue mix (a simple click track or a stereo mix feed from an interface or a live console) fed to the headphones via two TRS jack inputs on the rear of the unit.
An optional state-of-the-art stereo A-D converter is also available (the same card as used with the ISA430 MkII).
ISA series transformer-based preamplifier: Encased in a rugged and portable chassis, ISA One offers the classic Focusrite microphone preamplifier at its lowest cost to date
Flexible independent D.I. channel: ISA One is ideal for both engineers and demanding performers alike, featuring independent gain control, an output for routing to an amp, an independent XLR output on the rear and routing to the optional A-D converter
Switchable impedance: Choose one of four carefully selected input impedances, including the original ISA110 setting, to suit any microphone
Headphone output with volume control: ISA One can feed either a sum of the two inputs to the headphones output, or an external stereo cue mix (such as a stereo mix feed from an interface) via two TRS Jack inputs on the rear of the unit
Dedicated insert point: Allows you to place extra processing between the preamplifier or D.I. and the optional converter, such as an EQ or compressor
Optional stereo 192kHz A-D converter: You can choose to upgrade your unit with an optional digital card that delivers the best A-D performance in its class (dynamic range of 118dB). Alternatively, the ISA One Digitalcomes with the A-D converter as standard.
Mic Input Response
Line Input Response
Instrument Input Response
High Pass Filter
0 = +22dBu
-2 = +20dBu
-6 = +16dBu
-12 = +10dBu
-18 = +4dBu
-42 = -20dBu
Analogue Channel Inputs
Analogue Channel Outputs
Analogue Channel Additional I/O
Dimensions and Weight