Goldmund Telos 690 Integrated Stereo Amplifier

The Goldmund Telos 690 Integrated Stereo Amplifier brings Goldmund's proprietary Telos Class A/B amplification, digital processing and preamplifier functionality into a single reference component. The current Telos 690 combines substantial loudspeaker-driving capability with eight analog RCA inputs, USB Audio up to 32-bit/384kHz, S/PDIF and Toslink digital inputs, making it capable of anchoring both traditional analog systems and modern high-resolution digital playback systems. Goldmund

Goldmund's latest Rev. D specification sheet rates the Telos 690 at 190 watts per channel into 8 ohms and 260 watts per channel into 4 ohms, backed by dual 350VA toroidal transformers, a 46,000µF capacitor bank, 35dB gain and a damping factor of 600. Those current figures supersede earlier Goldmund documentation that listed 250W/8Ω and 320W/4Ω, so I would use the current Rev. D numbers on The Grid's listing. Goldmund

Goldmund Telos Class A/B Amplification

The Telos 690 is built around Goldmund Telos amplification technology, a circuit architecture introduced in the 1990s and continuously developed since.

Telos operates in Class A/B using highly linear analog components and a high-bandwidth circuit. Goldmund focuses heavily on reducing output impedance so the amplifier maintains electrical control over the connected loudspeaker, particularly the large excursions of bass drivers. Goldmund

The objective is not simply high output power. Low output impedance helps control woofer overshoot, while the high-bandwidth circuit is designed to minimize group-delay distortion. Goldmund also separates high- and low-current stages to reduce interaction and unwanted feedback between different sections of the amplifier. Goldmund

190 Watts per Channel Into 8 Ohms

The current Telos 690 specification is:

2 × 190W RMS into 8Ω at 1% THD
2 × 260W RMS into 4Ω at 1% THD

Maximum unloaded output before clipping is specified at 170V peak-to-peak at 1% THD. Goldmund

That combination gives the Telos 690 considerably more authority than its integrated-amplifier format might suggest and makes it appropriate for sophisticated passive loudspeakers where current delivery and driver control matter as much as nominal wattage.

Dual 350VA Toroidal Power Transformers

Goldmund equips the Telos 690 with two 350VA toroidal transformers, providing a substantial dedicated power foundation for its stereo architecture. Goldmund

The transformers feed a 46,000µF capacitor bank, while Goldmund's redesigned power-supply board increases available energy reserves and improves efficiency. The capacitor banks are specifically configured for stereo amplification. Goldmund

This reserve becomes particularly important during fast musical transients, where an amplifier must move quickly between relatively low output and large instantaneous power demands.

Damping Factor of 600

Goldmund specifies a damping factor of 600 at 1kHz into 8 ohms. Goldmund

That number is especially relevant to the Telos design philosophy. An amplifier doesn't simply need to accelerate a loudspeaker driver—it must also control its motion when the musical signal changes or stops.

The extremely low output impedance of the Telos architecture is intended to improve this control, particularly with large woofers, where uncontrolled movement can soften transient response and bass definition. Goldmund

Analog Preamplifier & Integrated Amplifier Architecture

The Telos 690 isn't simply a power amplifier with a volume control added to the front.

Its integrated architecture combines source selection, level control and Telos power amplification in one chassis, allowing a high-end system to eliminate the separate preamplifier and associated interconnects.

The current rear-panel configuration provides eight stereo analog RCA inputs, giving the Telos 690 unusually extensive connectivity for analog sources. Goldmund

That makes it particularly attractive for systems combining multiple source components while retaining the simplicity of a single amplification chassis.

High-Resolution USB Audio

Digital sources can connect directly to the Telos 690 through its USB Audio Class 2.0 input.

USB supports:

PCM sampling rates up to 384kHz
Bit depths up to 32-bit
DSD64 via DoP
DSD128 via DoP

Goldmund specifies native driver-free operation with compatible macOS and Linux systems, while Windows requires the appropriate driver. Goldmund

This means a computer or compatible digital transport can feed high-resolution audio directly into the Telos 690 without requiring a separate external USB DAC.

Coaxial & Optical Digital Inputs

In addition to USB Audio, the Telos 690 provides:

1 × 75Ω RCA S/PDIF digital input
1 × Toslink optical digital input. Goldmund

Combined with USB and the extensive analog input bank, this makes the Telos 690 considerably more versatile than a conventional analog-only integrated amplifier.

100dB Dynamic Range

The Telos 690 has a specified 100dB dynamic range, measured over a flat 22kHz bandwidth using true RMS methodology with the amplifier unloaded. Goldmund

Goldmund designs Telos amplification to preserve resolution not only during large dynamic passages but also at low playback levels. The company's objective is consistent transparency and microdynamic information across the amplifier's usable output range rather than an amplifier that only becomes expressive at higher volume. Goldmund

Low Noise & Distortion

The current published measurements include:

IMD (SMPTE): <0.02% unloaded
THD+N: <0.08% from 20Hz–20kHz at 30Vrms output
Output noise: <10µV from 20Hz–20kHz

Gain is specified at 35dB. Goldmund

Goldmund attributes Telos' low harmonic and intermodulation distortion partly to increased linearity throughout the individual amplification stages and isolation between high- and low-current circuits. Goldmund

Goldmund Mechanical Grounding

Mechanical behavior is treated as part of the amplifier's engineering.

The Telos 690 sits on Goldmund's distinctive Conic Feet, designed according to the company's Mechanical Grounding principles. Their function is to provide a controlled path for unwanted mechanical vibration to leave the chassis rather than accumulating within the component. Goldmund

Goldmund applies the same philosophy throughout its electronics and loudspeaker systems, treating mechanical vibration, electromagnetic interference and thermal management as interconnected aspects of signal integrity.

Micro-Blasted Aluminum Chassis

The Telos 690's enclosure is manufactured from an ultra-thick proprietary aluminum alloy with Goldmund's micro-blasted finish.

Its construction minimizes visible joints and screws while providing the structural rigidity, electromagnetic shielding and heat dissipation required by the internal electronics. Goldmund

The current standard finish is Grey, with Black available as a custom finish. Goldmund

Simple Reference-System Architecture

One of the strongest arguments for the Telos 690 is what it allows you to remove from a system.

A conventional reference setup might require a DAC, preamplifier and stereo power amplifier, plus additional interconnects and power cables. The Telos 690 can accept analog and high-resolution digital sources directly while providing the preamplification and Telos power stage within one chassis.

That makes it particularly compelling for a customer who wants genuine Goldmund amplification without building a large multi-component electronics stack.

Goldmund Telos 690 Technical Specifications

Current dimensional, performance and finish data are from Goldmund's latest Rev. D specification sheet. Goldmund

Important Specification Update

I would not copy the 250W/8Ω and 320W/4Ω figures found on older Telos 690 pages around the internet. Goldmund's original Rev. A material published those numbers, but the newer Rev. B manual and current Rev. D specification sheet state 190W/8Ω and 260W/4Ω. Goldmund

For SEO and customer confidence, The Grid listing should use the current manufacturer specification, while avoiding conflicting legacy figures.

Goldmund Telos 690 at The Grid HiFi

The Goldmund Telos 690 is an especially compelling foundation for a high-end system where the goal is to reduce component count without sacrificing reference-level amplification. With 190 watts per channel into 8 ohms, 260 watts into 4 ohms, a 600 damping factor, high-resolution USB audio and extensive analog connectivity, it can replace several separate electronics while retaining Goldmund's Telos architecture.

The Grid HiFi can match the Telos 690 with the appropriate reference loudspeakers, digital and analog sources, cabling, power and equipment support based on the room and listening priorities.

Considering the Goldmund Telos 690? Call The Grid HiFi at (713) 218-8120 to build and audition a complete reference system around it.