Ultrafide Amplifiers
Professional Sound. Engineered for Home.
Ultrafide amplifiers bring professional-audio engineering, high-current power delivery and a music-first approach into the home. Designed and manufactured in the UK, Ultrafide combines decades of pro-sound experience with refined hi-fi performance for listeners who want greater clarity, dynamics and emotional involvement.
From the highly configurable U4PRE pre-amplifier through to the U500DC, DIAS-U8 and SP500 power amplifiers, the Ultrafide range gives you a flexible route to powerful, transparent and highly controlled music systems.
The Ultrafide approach
Engineered for Musical Authority
Ultrafide designs focus on the aspects of amplification that make the biggest difference to real-world music listening: stable current delivery, low distortion, direct signal paths, controlled noise levels and the ability to retain composure as music becomes more demanding.
Ultra Sigma Technology
Ultrafide’s in-house Ultra Sigma output topology combines high efficiency with the speed, control and musical confidence required for serious loudspeaker systems.
High-Current Power Supplies
Large custom toroidal transformers and substantial linear power-supply arrangements help preserve control, dynamics and bass definition during demanding musical peaks.
DC-Coupled Signal Paths
DC coupling through key sections of the signal path is used to preserve accuracy and reduce unnecessary interference between input and output.
Professional Connectivity
Balanced XLR, RCA and flexible output arrangements make Ultrafide suitable for high-end home hi-fi, multi-amplifier systems and more specialist installations.
The Ultrafide range
Build an Amplifier System Around Your Music
Ultrafide offers a clear progression from advanced pre-amplification and flexible stereo power through to statement Class AB performance. Each model is designed to partner demanding loudspeakers while preserving the drive, detail and emotional scale of music.
The control centre of the Ultra Sigma system
Ultrafide U4PRE Pre-Amplifier
The U4PRE is Ultrafide’s advanced quad-output pre-amplifier, designed to become the central control point of a highly capable and expandable hi-fi system. It provides extensive analogue connectivity, a configurable phono stage and the flexibility to support multi-amplifier loudspeaker systems.
- Four simultaneous line outputs for multi-amping and flexible system expansion.
- Class A circuitry with a short, direct signal path.
- Highly configurable MM and MC phono stage for a broad range of cartridges.
- Six RCA and four balanced XLR inputs for source flexibility.
- Discrete Class A/B headphone amplifier with twin headphone outputs.
- OLED display and remote control for volume, balance, source selection and standby.
Ultra Sigma stereo power amplification
Ultrafide U500DC Power Amplifier
The U500DC is a powerful stereo amplifier designed around Ultrafide’s Ultra Sigma Class D platform. Combining serious output capability with dual-mono power architecture and selectable sonic character, it provides exceptional control for high-end passive loudspeakers.
- 500W per channel into 4 ohms and 250W per channel into 8 ohms.
- Ultra Sigma Class D topology using Delta-Sigma modulation.
- Dual-mono design with separate bridge rectifiers for each channel.
- 500VA custom toroidal transformer supporting a linear power supply.
- Pure Timbre and Vintage modes selectable from the rear panel.
- Balanced XLR and RCA inputs, with twin binding posts per channel.
Statement-level Class AB authority
Ultrafide DIAS-U8 Power Amplifier
The DIAS-U8 is Ultrafide’s statement power amplifier: a substantial dual-mono Class AB design created for music systems that demand exceptional current, grip and composure. It combines classic engineering principles with highly developed output-stage and grounding technology.
- 2kW of Class AB power across two independent amplifier channels.
- Dual-mono power architecture with separate high-tension and auxiliary rails.
- Twelve premium output devices per channel with equal-current-sharing design.
- 1000VA custom toroidal transformer for serious linear power delivery.
- Fully balanced topology with XLR inputs and passive link outputs.
- 50kg premium chassis with meticulous attention to grounding and noise control.
Compact form. Serious stereo power.
Ultrafide SP500 squaredPOWER Amplifier
The SP500 brings Ultrafide’s Ultra Sigma output technology into a compact, minimal 350mm-wide chassis. It is a powerful and highly flexible stereo amplifier for listeners who want reference-style grip and musical engagement in a more space-conscious system.
- 500W per channel into 4 ohms and 250W per channel into 8 ohms.
- Ultra Sigma Class D output topology derived from the U500DC platform.
- 500VA linear power supply for consistent, controlled performance.
- DC-coupled input-to-output architecture for clean signal transfer.
- RCA, XLR, binding-post and speakON connectivity for broad system flexibility.
- Rack-mount capability for studio, custom-install and specialist applications.
Product availability, finish options, connection requirements and the best Ultrafide configuration for your loudspeakers should be confirmed before purchase. We can help specify an appropriate pre/power combination around your sources, room and long-term system plans.
A flexible system foundation
From Stereo to Multi-Amplifier Systems
Ultrafide amplification has been designed to suit both high-performance stereo systems and more complex installations. The U4PRE’s quad-output capability, alongside the balanced and single-ended connections found across the range, gives you room to create a system that can evolve over time.
- Build a powerful stereo system with U4PRE and U500DC or SP500.
- Use multiple amplifier channels for bi-amping or more advanced loudspeaker control.
- Connect analogue and digital-era sources through extensive RCA and XLR provision.
- Match MM or MC cartridges through the U4PRE’s configurable phono platform.
- Choose DIAS-U8 where statement Class AB power and dual-mono control are required.
“Exceptional amplification should deliver the intimacy of the studio, the energy of live performance and the emotional scale of the music.”
At Brian & Trevor, we can help match Ultrafide amplification to your loudspeakers, turntable, streamer and room, then demonstrate the difference a carefully specified pre/power system can make.
Choose with confidence
Which Ultrafide Amplifier Is Right for You?
The ideal Ultrafide setup depends on your loudspeakers, preferred sources, room size and whether you want a flexible stereo system or a more ambitious high-power installation.
Choose U4PRE + U500DC
A highly flexible high-end pre/power combination with configurable phono capability, exceptional stereo output and a clear route towards future multi-amplifier expansion.
Discuss Ultra SigmaChoose DIAS-U8
The statement option for serious loudspeakers and listeners who want exceptional Class AB authority, full balanced operation and true dual-mono amplifier architecture.
Discuss DIAS-U8Choose SP500
A compact but powerful Ultra Sigma solution for systems where 500W-per-channel capability, professional connectivity and minimal casework are all priorities.
Discuss SP500Hear Ultrafide properly
Experience Power With Feeling
A personal demonstration is the best way to understand the scale, control and musical engagement Ultrafide amplification can bring to your hi-fi system.
Book a Demonstration
Hear Ultrafide pre/power amplification in a carefully matched music system.
Book an AppointmentMatch Your Loudspeakers
Discuss power requirements, balanced connectivity and the right amplifier platform for your system.
Ask for AdviceBuild a Better System
Explore pre/power, phono-stage and multi-amplifier possibilities around your music and room.
Speak to a Hi-Fi Specialist