90%
Thrax SPARTACUS 300
The Spartacus 300 is not just an amplifier—it’s a celebration of the legendary 300B tube, reimagined for the modern era. Combining the timeless warmth of Directly Heated Triodes (DHTs) with cutting-edge engineering, the Spartacus 300 delivers a listening experience that is both powerful and pure. With its minimalist signal path, innovative power supply, and meticulous craftsmanship, it stands as a testament to what tube amplification can achieve.
The Legendary 300B Tube, Perfected
At the heart of the Spartacus 300 lies the 300B tube, renowned for its exceptional linearity and harmonic richness. This iconic tube is used exclusively throughout the amplifier, ensuring a consistent and captivating sonic character. The Spartacus 300 employs only two amplification stages, preserving signal purity and delivering a sound that is both transparent and emotionally engaging.
Minimalist Signal Path, Maximum Fidelity
The Spartacus 300 features a transformer-coupled input and output, with no capacitors in the signal path. The input stage uses a silver/permalloy step-up transformer to add gain, while the output stage is driven by a phase-splitting transformer. This design ensures that the signal remains pure, free from the coloration and distortion often introduced by capacitors.
The output stage consists of four 300B tubes operating in a parallel push-pull configuration, centered around a custom transformer wound on a unique core material. Biased in pure Class A, this configuration delivers 50 watts of power with exceptional clarity and control, even on the most demanding loads.
Innovative Power Supply for Explosive Dynamics
The Spartacus 300’s power supply is a masterpiece of engineering. Based on a shunt regulator design, it utilizes another 300B tube to ensure stable power rails and instantaneous clipping with no modulation. This design allows the amplifier to deliver explosive dynamics and transparency, even under the most challenging conditions.
A nano-crystalline choke power supply filter further enhances performance, reducing noise and ensuring that the amplifier operates at its absolute best. The result is a level of clarity and speed that redefines what a 300B tube can achieve.
Auto-Bias and Microprocessor Control
The Spartacus 300 is designed for ease of use and reliability. A microprocessor manages the startup sequence, monitors tube operation, and oversees the regulated power supplies. The auto-bias systemcompensates for tube aging and ensures correct operation with any 300B tube, making tube replacement effortless.
Harmonic Richness and Tube Protection
A special filament heating circuit not only enhances the harmonic richness of the 300B tubes but also protects them, ensuring long life and consistent performance. Combined with the modular design, which allows for easy in-field servicing, the Spartacus 300 is built to last.
Safety and Stability
The Spartacus 300’s generously sized chassis encloses the tubes for safety and reduces airborne microphony. It also acts as a giant heatsink, ensuring optimal thermal performance. The amplifier’s torque binding posts provide secure connections, protecting your cables and ensuring the best possible signal transfer.
A New Benchmark in Tube Amplification
The Spartacus 300 is more than just an amplifier—it’s a revelation. Its combination of minimalist design, innovative engineering, and the legendary 300B tube delivers a sound that is both powerful and pure. Whether you’re listening to delicate acoustic passages or powerful orchestral crescendos, the Spartacus 300 brings your music to life with unparalleled clarity and emotion.
Experience the Spartacus 300
The Spartacus 300 is not just an amplifier—it’s a gateway to a new level of musical enjoyment. Its combination of timeless tube technology and modern engineering makes it the ultimate choice for those who demand the best.
Discover the power, purity, and passion of the Spartacus 300—and hear your music like never before.
WATT RECOMMENDS
Save your favorites. Compare them anytime.
Create a free HiFi Hub account to save products to your Wishlist and compare your favorites side by side.
Professional Reviews 90/100
Nicely Roasted
Sound Quality
91/100
Build Quality
93/100
Value for Money
84/100
The pure class A triode presentation of the SPARTACUS 300 stands out immediately, with Best of High End calling it an engineering-heavy 300B design that lets listeners hear the tube’s character with unusual clarity. Its 50W output, zero-capacitor signal path, and custom transformer work give it rare authority, purity, and musical pull.
What Reviewers Are Saying
Pros
Exceptional 300B purity and clarity, with a highly revealing triode character.
Strong for a tube amp, delivering 50W of pure Class A power with real authority.
Careful engineering and a minimal signal path support transparency and musicality.
&
Cons
Spatial performance is not described in much detail, so imaging strengths are less clearly documented.
Value for money is left largely unaddressed in the review, making cost justification hard to judge from the evidence available.
SOUND QUALITY PERFORMANCE 91/100
Reviewers are very enthusiastic about the amplifier’s overall sonic character, saying it lets listeners hear what a 300B can really do and calling the result “amazed”-worthy. The sound is described as pure class A triode presentation with strong praise for its naturalness and engagement, while the spatial description is much thinner than the rest of the commentary.
Transparency Resolution
93/100
The amplifier is presented as highly revealing, with reviewers saying you can “actually hear what a 300B really sounds like” and praising the sense of purity in the signal path. The language suggests excellent clarity and a low veil, though the reviews do not go into granular detail about micro-detail or edge definition.
Tonal Balance Musicality
94/100
This is where the strongest praise lands: the SPARTACUS 300 is portrayed as a deeply satisfying 300B design with a captivating, natural triode character. The reviews frame it as highly musical and emotionally compelling, with tone and texture clearly central to its appeal.
Dynamics
92/100
The quoted 50W of pure class A triode power and the “engineering overkill” language point to substantial authority for a tube amplifier. Reviewers clearly admire its confidence and scale, though they do not provide much direct commentary on grip under difficult loads or explosive transient attack.
Soundstage Imaging
86/100
The reviews do not give much direct description of width, depth, layering, or image precision. There is no specific claim of holographic staging or pin-sharp placement, so this remains more implied than well documented.
Assessments of Build Quality, Usability, and Overall Propositions.
Build Quality
93/100
Reviewers describe the amp as “engineering overkill” and praise the use of custom transformers, a shunt-regulated supply, and a very simple signal path. The modular design, sealed chassis, auto-bias system, and microprocessor control also suggest careful execution and thoughtful real-world engineering.
Value for Money
84/100
None of the reviews clearly discuss whether the asking price is justified or competitive versus alternatives, so there is little direct value commentary to work with. At this level and with this kind of ambitious tube implementation, the price will likely be a serious consideration for buyers, but the review set itself does not frame it as either a bargain or a rip-off.
Reviews
Online Reviews & Mentions
YouTube Reviews
Forum Mentions
No forum mentions found yet
Verified Dealers
Online Dealers
All Dealers
Zoom out the map to see more dealers
Authorized dealers for Thrax SPARTACUS 300
- 3mA Audio — online and in-store — Houston, Texas, United States (website)
- Ana Mighty Sound — online and in-store — Paris, Île-de-France, France (website)
- BELHIFI — online and in-store — Meise, Vlaams Gewest, Belgium (website)
- Cake Audio — in-store — San Clemente, California, United States (website)
- Design Audio — in-store — Aix en Provence, Île-de-France, France (website)
- Dr Vinyl — in-store — Middle River, Maryland, United States (website)
- Dream Audio Components — online and in-store — Dunaharaszti, Hungary (website)
- Madformusic — in-store — Arese, Lombardia, Italy (website)
- Rhapsody — in-store — Ravenstein, Noord-Brabant, Netherlands (website)
- Stellar Home Audio — in-store — Commack, New York, United States (website)
and 2 more verified dealers