Circle Labs products are the outcome of 25 years of research, careful design and passion in perfect amplification of sound. This came from the need for sound which could bring the full expirience of music to the listener without losing any of its charm, harmony or elegance.
For years Circle Labs has been producing and designing specialised devices dedicated to research in microbiology. Our equipment can be found in many vanguard scientific facilites in Poland and around the world. However, the constructor and owner of the company Krzysztof Wilczyński, always had a keen interest in audio devices. In 2019 original Circle Power technology drew the attention of top polish producers of hi-end audio equipment, which resulted in the birth of reference monoblocks. That was the spark which ignited a fire of dynamic development for the company and the bringing of our products to a wider audience.
CIRCLE LABS A200
This amplifier uses proprietary solutions from Circle Labs. The minimalist preamplifier based on the Siemens nos tube is combined with a solid-state power amplifier in Circle Power technology. Final stage ensures appropriate dynamics and good drive for most of the loudspeakers available on the market. The amplifier is equipped with a remote control.
The A200 is a hybrid integrated amplifier that offers power output of 120W/8Ω, 200W/4Ω and is equipped with a balanced XLR input, four pairs of RCA inputs and a direct power amplifier input that bypasses the preamplifier.
The A200's preamplifer is designed around a NOS Siemens vacuum tube with stable polarisation; this minimalist solution allows for the lowest possible number of passive components: one vacuum tube, a resistor, and a state of the art capacitor made of solid copper foil. The extremely short signal path directly influences the neutrality of sound and dynamism of transmission.
The A200's "Circle Power" topology is an original development of Circle Labs and we believe is the best combination of tube and transistor devices. This design uses a single-ended input stage with current steering of a BJT output stage and combines the detail and precision of single-ended systems with the efficiency and dynamics of balanced systems. The A200's power amplifier is a true dual-mono design with separate toroidal transformers and power supplies with a combined capacitance of 200,000µF
CIRCLE LABS P300
The P300 preamplifier is a fully balanced design from input to output. The idea behind the construction of the P300 was to build a preamplifier as neutral to the signal as possible. With the shortest possible signal path. Internal cabling length is minimal.
It was designed around the newest JFET and BJT transistor types and uses a proprietary Circle Amp topology. Volume is controlled by a relay operated resistor ladder and offers 63 step resolution. An aluminum remote is supplied. We designed a specially built, low noise power supply based on two independent channel transformers with LL cores and Elma SILMIC II capacitors. The power supply has two cascading steps of stabilisation. The stabilisers use an LED matrix as a source of reference current, characterised by remarkably lower noise than traditional merged Zener diodes. The frieze-finished aluminium 5754 casing is crafted using digital CNC machines.
CIRCLE LABS M200
CIRCLE LABS V1000
The V1000 is a reference-grade phono preamplifier designed for demanding vinyl enthusiasts who want absolute control, purity, and musical realism from both MC and MM cartridges. It supports two cartridges independently, offering fully adjustable impedance from 10 to 1000 Ohms and capacitance from 0 to 320 pF, allowing precise matching with any pickup. At the heart of the design lies a proprietary Step-Up Transformer — developed entirely in-house — placing the V1000 among the few phono stages built around a truly original SUT architecture. Its primary winding uses Lica wire in a 25-strand configuration with silk insulation, while the secondary winding is crafted from high-grade copper, resulting in exceptionally low resistance and minimal signal loss directly from the cartridge.
From the transformer, the signal enters a no-feedback MM stage built on four ECC88/6922 tubes, chosen for their musicality, detail, and natural dynamics. The entire unit follows a true dual-mono layout, with completely isolated circuitry for the left and right channels to preserve channel separation and soundstage integrity. Power is supplied through a dedicated external unit housing the transformers, using Mundorf polypropylene capacitors and a cascaded, two-stage stabilizer for ultra-clean, interference-free operation.
On the front panel, users can select between standard RIAA equalization or apply custom adjustments — ideal for collectors of pre-RIAA pressings who want historically accurate reproduction. Additional controls include MC/MUTE/MM switching and arm/insert selection, giving the listener full command over every aspect of playback. The V1000 is engineered for one purpose: to reveal the full emotional depth and analogue truth hidden in every record.