Focusrite
Focusrite AMS-ISA-ONE Heritage Mic Preamp with DI
★★★★★
XLR
Capture Pristine Audio with the Focusrite ISA One Heritage Microphone Preamp The Focusrite ISA One Heritage delivers the classic Focusrite microphone preamp sound in a rugged and portable package. Featuring a Lundahl input transformer, variable impedance selector, and independent DI channel, the...
$699.99*
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Overview
Capture Pristine Audio with the Focusrite ISA One Heritage Microphone Preamp
The Focusrite ISA One Heritage delivers the classic Focusrite microphone preamp sound in a rugged and portable package. Featuring a Lundahl input transformer, variable impedance selector, and independent DI channel, the ISA One is a versatile tool for recording vocals, instruments, and more.
Specifications:
- Brand: Focusrite
- Model: AMS-ISA-ONE
- Type: Microphone Preamp
- Preamplifier: ISA series transformer-based
- Input Transformer: Lundahl LL1538
- DI Channel: Independent, with gain control and amp output
- Impedance: Switchable, four settings
- Headphone Output: With volume control
- Insert Point: Dedicated
- A/D Converter: Optional stereo 192kHz
- Metering: Backlit VU meter, six-LED peak meters
Key Features
ISA series transformer-based preamplifier: Encased in a rugged and portable chassis, ISA One offers the classic Focusrite microphone preamplifier in a highly cost-effective and flexible package
Flexible, independent DI 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 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 DI 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, with a dynamic range of 118dB
Lundahl LL1538 Input Transformer: The original mic transformer used in the original Red modules helps to provide the unique sound and performance of this ground-breaking design
Backlit VU meter with variable calibration: ISA One has 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
Specifications
Preamplifier Type
ISA series transformer-based
Chassis
Rugged and portable
DI Channel
Flexible, independent with gain control
DI Output Options
Amp routing, independent XLR output
Input Impedance
Switchable (4 settings, including ISA110)
Headphone Output
With volume control, sums inputs or external cue mix
Insert Point
Dedicated, preamplifier/DI to optional converter
Input Transformer
Lundahl LL1538
Metering
Backlit VU meter with variable calibration, two six-LED peak meters
Metering Options
Pre- or post-insert
Pros & Cons
👍 Pros
- Encased in a rugged and portable chassis, making it suitable for both studio and mobile recording environments.
- Features a flexible, independent DI channel with independent gain control and multiple output options for instruments.
- Offers switchable impedance with four carefully selected input impedances, including the classic ISA110 setting, to match various microphones.
- Includes a dedicated insert point, allowing for additional processing like EQ or compression between the preamp and optional converter.
- Equipped with a backlit VU meter with variable calibration and two six-LED peak meters for precise input monitoring.
👎 Cons
- The stereo 192kHz A-D converter is an optional upgrade, meaning the unit does not include digital conversion out of the box.
- While portable, the "rugged" chassis may still be subject to wear and tear in demanding field use without additional protection.
- The independent DI channel's routing options, while flexible, may require a learning curve for new users to optimize their setup.
- The inclusion of only one preamplifier means it is not suitable for multi-microphone recordings without additional units.
- The "classic Focusrite microphone preamplifier" sound profile, while revered, may not be the preferred sound for all audio engineers.
Frequently Asked Questions
Does the Focusrite ISA One include a built-in A-D converter?
The ISA One has an optional stereo 192kHz A-D converter available for upgrade, which delivers high-performance digital conversion, but it is not included by default.
Can I use this preamp for recording instruments directly?
Yes, it features a flexible, independent DI channel with its own gain control, an output for routing to an amp, and an independent XLR output on the rear.
How does the ISA One cater to different microphones?
The unit offers switchable impedance with four carefully selected input impedances, including the original ISA110 setting, to best suit various microphones.
Can I add external audio processing gear to the signal chain?
Yes, there is a dedicated insert point that allows you to place extra processing, such as an EQ or compressor, between the preamplifier/DI and the optional converter.
How accurate is the metering on the ISA One?
It features a backlit VU meter with variable calibration for analogue and digital recording media, alongside two six-LED peak meters, which can monitor inputs either pre- or post-insert.
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