

Antelope Audio A4-1B Complete Edition
(B-Stock)
Ex demo unit. Full warranty.
Condition: Mint
Accessories: Box, USB and power cable
Voltage: 95-245V
A4-1B combines the legendary sound and design of analogue Opto-Tube compressor with modern-day workflow enhancements. Experience its signature hardware audio processing or take it a step further by accessing an array of contemporary functionalities.
A4-1B was designed to preserve vintage Opto-Tube units' highly praised smoothness and musicality. Even when pushed to the limit, the compressor remains transparent, breathing new life into vocal tracks, bass, keys, or percussion. A4-1B sounds and reacts just like the legendary hardware that inspired it allowing you to apply the legendary sound of Opto-Valve compression to your modern production.
High-quality components ensure A4-1B's superior sound and performance consistency across the whole frequency spectrum. This all-analogue powerhouse was made to last and faithfully follow the legacy it was built upon. Custom UK-manufactured transformers allow for a tight low-end and high-fidelity audio reproduction. The signature sound of the unit is achieved thanks to its premium tubes. Those provide A4-1B with extra analogue warmth and precision. Electricity is the heart and soul of high-end analogue gear so we packed A4-1B with an efficient PSU incorporating advanced automatic voltage adaptation for even greater stability and noise reduction.
A4-1B is the first in a series of automated outboard analogue units developed by Antelope Audio. We want to introduce high-quality audio hardware to the current generation of audio producers and artists. Thanks to proprietary digital technologies these units will not only be given a new life but will be adapted to the current standards of the professionals and enthusiasts. This all-analogue design allows the units to be used traditionally but the brand new digital features unlock their full potential.
The A4-1B digital control panel is available as a VST/AU/AAX plugin compatible with any modern-day DAW. The unit is easily integrated into fully digital, all-analogue, or hybrid studio setups. The intuitive software makes preset management a breeze so you can apply your signature settings to various sessions and access them from any place in the studio.
The A4-1B motorised potentiometers will not only instantly react to any change you apply on the hardware unit physically or digitally, those can also be fully automated in the app or control panel. The value of any parameter of the unit, including the compressor Attack, Release, Gain, Threshold, and Ratio can change throughout your session - just as if you are using a native plugin.
The software control panel allows for fast and easy preset recall but just like any other Antelope Audio plugin and unlike most analogue gear, it allows you to do A/B preset comparisons quickly and easily.
By modern-day standards filtering and side-chain are crucial features of compressors. The legacy unit that inspired A4-1B wasn't built with these requirements in mind so we added them as unlockable extras to the digital-only feature set of the unit. The available High, Low, and Band-Pass Filters are useful for targeted compression. De-essing capabilities and Side-Chain compression are crucial for a unit, known as one of the go-to compressors for vocal processing, and are also accessible via the software panel of the unit.
Among the many stand-out features of A4-1B are its calibration systems. These ensure consistent performance and long-term reliability of the tubes of the unit, a crucial feature when using dual units for enhanced stereo matching. A4-1B offers an Opto-Cell Test System, and self-calibration of the VU meters, and the meter reference level (- 10 dBu / 0 dBu / +4 dBu / +20 dBu). The motorised potentiometers can also be readjusted. All three calibration types are accessible in the unit's control panel.
-
Type: Analogue tube optical compressor with fully motorised potentiometers
-
Signal Path: 100% analogue with UK-built output transformers
-
Filters: Selectable high-pass, band-pass and de-esser modes
-
Attack/Release: Continuously variable
-
Ratio: Continuously variable from 2:1 to 10:1
-
Frequency Response: 20 Hz – 20 kHz (±1 dB)
-
Noise Floor: < –80 dBU
-
Threshold: Adjustable from +20 dBU (off) to –40 dBU
-
Timing Modes: Fixed, Manual, Hybrid
-
Output Gain: Off to +30 dBU
-
Input Impedance: 10 kΩ
-
Metering: VU meters switchable for input, gain reduction, or output
-
Connectivity: Balanced XLR & TRS I/O, two bus connectors for sidechain linking, USB-C for remote control
-
Software: Perpetual DAW plug-in licence (VST3, AU, AAX) for automation, filtering, and preset recall
-
Bonus Content: 2-year Synergy Core Native subscription with 70+ effects (compressors, EQ, reverb, delay, pitch correction & more)
-
Dimensions: 483 × 88 × 252 mm (W × H × D)
-
Weight: 4.4 kg
-
Included: Power cable, USB-C cable, “Get Started” sheet, plug-in licence info sheet
Product Overview
Product Specifications
Product Videos
Shipping Information
We provide free shipping on most items and Next Day delivery on all orders completed before 12pm (noon!) so you don’t have to pay extra or wait long to start enjoying your new equipment.
We use DPD to ship the majority of our orders within the UK. International locations will vary, learn more here.
Product Support
All of our B-Stock items are sold on behalf of our manufacturer partners and are under 3 month Make Noise Pro Audio warranty and in certain circumstances the original manufacturers warranty too. We pride ourselves on offering the best support both before and after sale. If you have any questions, please get in touch.
ANT-A41B

Antelope Audio A4-1B Complete Edition (B-Stock)
B-Stock Gear FAQs
What does B-Stock mean?
In the UK you can only sell items as New if they are in their unopened, original packaging. But what happens to the items that may have been sold and returned within the purchase cool off period? They can’t be sold as new anymore because the box has been opened. It’s not new, but it’s also not second-hand, so it is then classed as B-Stock and typically priced somewhere in between. The same also applies for items that might have been scratched or dented in the manufacturing process or during delivery.
All of our B-Stock items are sold on behalf of our manufacturing partners and are under 3 month Make Noise Pro Audio warranty and in certain circumstances the original manufacturers warranty too.
All units will have been either fully tested by us in-house or a factory QC by the manufacturer where appropriate.
What advantages are there to buying B-Stock?
B-stock units are usually in "as new" condition. You get the reassurance of being a relatively unused product with the lower cost vs buying new.
Do B-Stock units have any warranty?
3 month manufacturer warranty through Make Noise Pro Audio.
