AGD Gran Vivace MKIII
Best monoblock amplifier for audiophiles seeking high-efficiency power and tube aesthetics.
Experience unparalleled audio performance with the AGD Gran Vivace MKIII, a state-of-the-art monoblock power amplifier. This amplifier family introduces the revolutionary GaNTube™ technology, integrating Gallium Nitride power stages within a vacuum tube for the most advanced design available. It delivers a robust 400W into 4Ω with an impressive 50A peak output, capable of driving demanding loudspeakers and filling large rooms with rich, musical sound. Crafted in the USA, the Gran Vivace MKIII represents a significant leap in high-fidelity audio amplification.
$18999.00
Owner Satisfaction
4.8
/ 5
Category Rank
37
/ 1719
#37 in Power Amplifiers
Price vs Category Average
+130%
Above average
Maximum Output Power (CEA-2006), 4Ω
400
/ W
Who it's for
- Audiophiles seeking cutting-edge efficiency and transparent signal delivery
- Listeners prioritizing natural, uncolored soundstage reproduction
- Design-conscious collectors valuing unique, high-end aesthetic craftsmanship
Who should skip it
- Budget-focused buyers looking for entry-level or mid-range pricing
- Shoppers preferring convenient, mainstream retail availability
- Owners of mismatched or lower-quality audio components
Performance breakdown
Power Delivery
Effortlessly drives demanding loudspeakers with 400 watts of clean, stable power.
Signal Clarity
The ultra-low noise floor ensures a pristine, transparent listening experience.
Efficiency
High-performance GaN technology minimizes heat while maximizing energy conversion.
Build Quality
Innovative glass tube design combines modern engineering with premium craftsmanship.
Dynamic Range
High-speed PWM switching captures every nuance of complex musical passages.
System Protection
Comprehensive safety circuits provide peace of mind during high-output sessions.
Key Specs
Maximum Output Power (CEA-2006), 4Ω
400W
THD+N 10W/1KHz
<0.0075%
Signal to Noise ratio at 1kHz
>110 db
Bandwidth ±0.5dB
20Hz÷20KHz
Efficiency%
>94%
Output Noise (A-weighted)
≤ 45μV
PWM Frequency
800kHz
Dimension
11"x11'x5" (279x279x127mm)
Features
- Single Channel Class-D Amplifier
- Fully integrated into Glass Tube Enclosure
- Gallium Nitride 600 V MOSFET Power Stage
- Up to 400 W 4 Ω (GaNTube 120KT model)
- 800 kHz PWM
- ≥ 94% Efficiency
- Noise floor at ≤ -130 dB
- Fully protected (OVT, OVC, DC)
What customers say
Customers consistently praise the AGD Gran Vivace MKIII for its exceptional sound quality and sophisticated design. Reviewers highlight its ability to deliver a remarkably clear, dynamic, and immersive audio experience, often describing it as a significant upgrade. The meticulous build quality and elegant aesthetics also receive high marks, reinforcing its premium standing. Enthusiasts appreciate the innovative engineering that contributes to its stellar performance, making it a highly regarded component in high fidelity systems.
Know before you buy
The GaNTube technology integrates Gallium Nitride MOSFETs directly into a glass vacuum tube enclosure. This design combines the high-speed efficiency and precision of Class-D amplification with the aesthetic and sonic characteristics traditionally associated with tube-based audio equipment.
Yes, the Gran Vivace MKIII is designed for demanding loads. It delivers 400W into 4Ω and features a 50A peak output, providing the necessary current to drive complex loudspeaker designs with ease.
The high 800 kHz Pulse Width Modulation frequency allows for a wider bandwidth and more accurate signal reproduction. This results in a cleaner, more detailed sound with a very low noise floor of ≤ -130 dB.
The Gran Vivace MKIII is a single-channel monoblock amplifier. You will need to purchase two units to achieve a stereo configuration.
The unit is fully protected against common electrical issues, including Over-Voltage (OVT), Over-Current (OVC), and DC offset. These built-in safeguards ensure both the amplifier and your connected speakers remain protected during operation.
The Gran Vivace MKIII operates at an efficiency of ≥ 94%. This significantly reduces heat generation and power consumption compared to traditional Class-A or Class-AB amplifiers, allowing it to run cooler while delivering high power output.
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