IGS Audio Thermidt Code 3530 – High-End Tube Amplifier

OVERVIEW

Studio Precision Meets Hi-Fi Passion

The Thermidt Code 3530 represents a completely new chapter in IGS Audio‘s approach to high-end tube amplification. This is not an experiment – it is a fully refined, mature design where nothing is left to chance. Backed by 20 years of audio engineering expertise and thousands of hours of critical listening in professional studios and showroom environments, the TRM 3530 is a masterclass in tube technology. Designed with raw passion for music, it stands as our ultimate statement in sound reproduction. Simply flawless.

Pure Polish Engineering. Uncompromised Sound.

Sound & Application

Created for audio enthusiasts who demand clarity, speed, and emotional depth, the Thermidt Code 3530 utilises a unique Negative Cathode Feedback (NCF) topology. This delivers exceptional detail, firm bass control, and remarkable stability, revealing the true, natural character of every recording. Whether rediscovering classic pressings or evaluating a complex master, Thermidt Code brings music to life with effortless dynamics and openness.

With its robust current delivery, the amplifier effortlessly drives both 4Ω and 8Ω loads – handling everything from compact bookshelf monitors to demanding floor-standing loudspeakers with absolute authority and grace.

Construction & Components

Thermidt Code 3530 is a push-pull Class AB (fixed bias) stereo amplifier delivering 2 x 32W of pure power with ultra-low distortion (under 0.03% at full power). The power stage is driven by four 5881 power tubes, guided by two 6BL8 triode-pentodes in the driver stage.

By optimising the operating point of the input stage, IGS Audio achieved an astonishing frequency response of 10 Hz to 50 kHz (+/- 1 dB, APx) – an elite-level metric reserved strictly for true reference-grade audio equipment.

No Hi-End amplifier is complete without uncompromising components. The signal path features premium Mundorf Silver Oil capacitors paired with ultra-precise Vishay Dale 0.1% resistors throughout. At its heart lie our divine, custom-designed output and power transformers, manufactured locally by UTM Industry.

For precise control, the front panel features a classic RCA input selector (CD, DAC, AUX) paired with a 24-step ELMA attenuator (Swiss Made, backed by a lifetime warranty). To satisfy true low-end connoisseurs, IGS added a 4-step bass boost switch (from 0 to +6dB at 100 Hz and shelf below), offering tailored low-frequency contouring without degrading mid-range clarity.

Built Rigid. Plays Effortlessly.

Chassis & Craftsmanship

The Thermidt 3530 debuts an all-new, ultra-rigid chassis manufactured entirely in Silesia, Poland, by our trusted production partners in MJK Zabrze. Machined from premium duralumin, the enclosure combines lightweight properties with extraordinary structural strength, effortlessly supporting the heavy UTM transformers without structural deflection.
The top plate features a CNC-machined panel that shields internal components while lending the amplifier a timeless, functional elegance. Strategically engineered thermal vents create a natural „chimney effect,” ensuring optimal cooling and extending tube life. The rear panel is fitted with gold-plated input Cinch sockets and rugged speaker terminals, making daily operation clean, intuitive, and reassuringly tactile.

Designed to Last a Lifetime.

Enduring Reliability & Usability

Built like a tank and designed for seamless integration into any high-end audio chain, the Thermidt 3530 is engineered to serve for decades. From the indestructible ELMA switch and industrial-grade UTM transformers to the rock-solid duralumin chassis, every element has been selected to ensure uninterrupted performance day after day. It is not just an audio component – it is an investment in timeless sound quality.

“Try Thermidt in your own system. We are confident you won’t be disappointed.”

KEY HIGHLIGHTS

Pure Polish Engineering

Designed and manufactured in Poland, the Thermidt Code 3530 combines more than two decades of audio engineering experience with meticulous craftsmanship and premium construction.

Unique Negative Cathode Feedback Topology

The proprietary NCF topology delivers exceptional detail, controlled bass and remarkable stability while preserving the natural character and emotional depth of your recordings.

2 x 32W Class AB Tube Amplification

Its push-pull Class AB power stage uses four 5881 power tubes to deliver 2 x 32W of refined, dynamic power, with the ability to drive both 4Ω and 8Ω loudspeakers.

Reference-Grade Frequency Response

With a measured frequency response extending from 10 Hz to 50 kHz at ±1 dB, the Thermidt Code 3530 provides exceptionally wide and linear bandwidth for high-end music reproduction.

Premium Mundorf & Vishay Dale Components

The audio signal path incorporates Mundorf Silver Oil capacitors and ultra-precise Vishay Dale resistors, selected to complement the amplifier’s high-performance tube circuitry.

Custom UTM Industry Transformers

Custom-designed power and output transformers manufactured by UTM Industry provide the robust current delivery and controlled performance required for demanding loudspeaker loads.

Swiss-Made ELMA Attenuator

A 24-position ELMA attenuator provides precise, repeatable volume adjustment, complemented by high-quality construction and a lifetime warranty.

Adjustable Bass Contour

A four-position bass control provides Flat, +2 dB, +4 dB and +6 dB settings at 100 Hz, allowing the low-frequency response to be tailored to your system and listening preferences.

Ultra-Rigid Duralumin Chassis

The custom enclosure is machined from premium duralumin, providing exceptional structural rigidity while supporting the amplifier’s substantial transformers without unwanted chassis deflection.

Designed for Long-Term Reliability

From its industrial-grade transformers and durable ELMA controls to its robust chassis and carefully engineered thermal ventilation, the Thermidt 3530 is designed to provide dependable performance for decades.

FEATURES

• 2 x 32 W Class AB (5881 tubes)
• IGS unique Negative Cathode Feedback (NCF) topology
• Custom-designed UTM Industry power and output transformers
• Mundorf Silver Oil capacitors and Dale resistors throughout the audio path
• 8 Hz to 50 kHz (±1 dB, APx) bandwidth
• 24-position ELMA attenuator (Swiss Made), 0.1% resistors
• Bass Contour adjustment (Flat to +6dB @100Hz boost)
• A completely new enclosure, proudly manufactured in Poland

TECHNICAL SPECS

HARMONIC

Harmonic Distortion: Max 0.15% @32W, 100Hz

Engineer’s Custom Tube Set: Yes

INPUT & OUTPUT

Inputs: 3 Pairs of RCA Connectors

Input Sensitivity: 0.775V

Input Pad: 3 Pairs of RCA Connectors

DAC: LDAC APTX HD/APTX-LL/APTX/SBC/AAC with 24bit/96kHz (Optional)

Output Impedance: 4 or 8 Ohm

QCC5125 Bluetooth: (Optional)

LEVELS

Max Input Level: 2V RMS

Dynamic Range: 98dB

TIME CONSTANTS

S/N Ratio: >97dB

BANDWIDTH

Frequency Response: 10Hz-50kHz +/-1dB

DISTORTION (@ 20 HZ – 20 KHZ)

THD: 0.01% @ 1W, 1kHz

THD+N: 0.03% @ 1W, 1kHz

IMD: Max 0.35% at @1W, 1kHz

Crosstalk: >89dB @ 1kHz

POWER

Voltage: 115V or 230V AC, 50 or 60 Hz

Power Consumption: 180VA

PACKING BOX

Dimensions: 80 cm x 60 cm x50 cm (EUR half pallet)

Shipping Weight: 35kg

OTHER

Tone Control:

• Flat
• Bass (+2, +4, +6dB@100Hz)

Tubes:

• 2 x 5881
• 2 x 6BL8