Note that this is a discontinued product. You may want to visit the brand's page here to browse their newer products.
What reviewers think
Magazine reviewers and YouTubers have tried this product—so we've summarized their strongest opinions below.
Compared to their other products
We think it's helpful to understand how this product fits into the brand's full lineup (below). To learn more about these products, visit the brand's page.
Chubby Jinx
- Positioning: The entry-level stereo amplifier in the lineup.
- Description: Offers a sweet sound with its 6V6 tubes, providing warmth and texture. Unlike the Kenzie Ovation, which focuses on low noise for headphones, this is tailored for stereo listening with a more neutral and resolving sound, making it ideal for small rooms and budget-conscious users.
Kenzie Ovation
- Positioning: A mid-range hybrid amplifier designed for both headphones and speakers.
- Description: Praised for its romantic sound and low noise, making it perfect for high-efficiency headphones. It differs from the Bryce Monos by offering a more intimate sound with less power.
Stereo 17 - Little Nugget
- Positioning: A compact stereo amplifier offering a no-compromise entry into bespoke audio.
- Description: Known for its EL84 tube bliss, provides a stable 17 watts, making it suitable for high-sensitivity speakers in small rooms. Unlike the Nautilus, which offers more power and versatility, this focuses on delivering a liquid midrange.
Nautilus
- Positioning: A flagship personal audio integrated amplifier.
- Description: Celebrated for its dual-mono layout and ultra-wide bandwidth, offering a reference-class sound. It stands out from the Arch Monos by providing a more compact solution with excellent headphone compatibility.
Bryce Monos
- Positioning: High-end single-ended amplifiers in the lineup.
- Description: Deliver ultra-wide bandwidth and high output, making them suitable for most speakers. Compared to the Arch Monos, which offer more power, these focus on single-ended purity.
Arch Monos
- Positioning: The flagship monoblock amplifiers in the lineup.
- Description: Designed for ultimate fidelity and power, with a bandwidth of 2Hz to 110kHz. They surpass the Bryce Monos in power and transparency.
Read the reviews
Manufacturer's notes
The Black Pearl has no compromises. Our skilled team assembles each unit entirely by hand. There is not a single IC, voltage regulator, or silicon chip in the Black Pearl, this amplifier is built in accordance with classic techniques and will last a lifetime because of it. Like Calypso, each channel component is matched by hand throughout the entirety of the amplifier.
The front end of this amp is paired with a massive tube rectified dual mono power supply that ensures tight bass and earth-shattering slam. Our goal with the Black Pearl was to honor the 300B: to do so we did a classic implementation with a single gain stage, zero feedback, and close attention to grounding techniques. The result is a deeper connection with your music, and an inky black background on headphones with no hum noise.
The Black Pearl measures a shocking distortion figure of less than 0.5% which is even more impressive when you consider the aforementioned single triode gain stage and absence of feedba...
- Input sensitivity: 2V P-P
- Noise @ 8ohm: 530µV RMS
- Max Power @ 8ohm: 8 watts RMS
- Bandwidth: 8hz to 28khz @ 1 watt -2db
- Dimensions: 14"deep x 19"wide x 8"tall
- Weight: 98lbs (126lbs shipped)
- Speaker configurations: 4ohm/8ohm or 8ohm/16ohm
Our take on the brand
Used
ampsandsound
What if you spend a bit more?

Our Summary
Product Strengths
- Highly customizable, allowing users to request specific configurations and tube types
- Offers a wide range of tube rolling options to pinpoint the desired sound signature
- Price-to-performance ratio is excellent, competing with amps costing around $5,000
- Can drive high impedance headphones like ZMF, HD 800, and T1, as well as planars and low ohm headphones with specific tube configurations
- Can sound very good with inexpensive tubes, but can be elevated to a ridiculous performance level with higher end tubes
- There is a HeadFi thread to help with connectivity options
Product Considerations
- Ordering process is unconventional, requiring direct communication through a HeadFi thread
- There is a wait time for builds, potentially around six months
- Tube rolling can become expensive due to the variety of options and the cost of some tubes
Takeaway: The Glenn is a highly customizable amplifier that provides excellent performance for the price, especially for those who enjoy tube rolling and experimenting with different sound signatures. It is a versatile amp that can drive a wide range of headphones, making it a great choice for many audiophiles.
Video review
Our take on the brand
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Our Summary
Product Strengths
- They transport you to a new venue instantaneously, engaging every one of your senses the minute you flip their on-off switch
- They deliver nuance, grace, and thunderous force no matter the speaker or the source equipment
- They deliver a level of detail that is exceptional, allowing you to hear subtle nuances in music
- They offer an enjoyable listening experience due to the output tubes being triode strapped, providing a warmer sound that sits just to the right of neutral
- They are fast and capable of keeping up with complex music, delivering impact and transforming the listening experience into a visceral one
Product Considerations
- Setting up the Zions requires work and effort, including adjusting AC Balance, DC Balance, and power tube Bias, which can take about an hour and a half
- Adjusting AC Balance requires a total harmonic distortion analyzer or an oscilloscope and a signal generator
- Changing tubes requires bias checks after 10 hours, a full checkup after 100 hours, and a third adjustment at about 500 hours
- They require the user to operate it properly with no automatic or safety feature to prevent you from driving off the road
- Matched power tubes are really important because the Zions only have a single bias setting for both power tubes
Comparisons (according to reviewers)
- The Zions are Justin's take on Citation V and he improved the original design by splitting left and right channels into their own chassis and replacing the solid-state rectifier with a 5AR4 (or 5U4G) rectifier
Takeaway: The ampsandsound Zions are exceptional amplifiers that deliver a high level of detail, nuance, and an enjoyable listening experience, and they are built with great care and attention to detail. For those who appreciate the work involved in setting them up, the Zions provide a rewarding and immersive audio experience.
Video review
Our take on the brand

Our Summary
Product Strengths
- Powerful, able to drive any speaker at any level with ease
- Delivers a new dimension in realism at any volume level, exposing the timbre of bass instruments unlike ever heard before
- Reveals harmonic quality of instruments and voices
Product Considerations
- Heavy, weighing 140lb (63.5kg), requiring assistance for moving and unboxing
- High running temperature (55-65oC across the chassis) and draws 500W from the wall when idle
- When speaker cables are terminated with spade lugs, caution is advised as the posts are close together
- Output is floating—it should not be connected to any loudspeaker with a grounded 'black' terminal
- BAT components take a long time to "break in" (400-500 hours of use)
Takeaway: The BAT REX 500 is a very powerful amplifier that drives speakers with ease and reveals new levels of realism in familiar recordings. It is a must-audition for those seeking reference-level power amplification.
Video review
Our take on the brand

Our Summary
Product Strengths
- Delivers 350 watts into 2-ohm, 4-ohm, or 8-ohm loads
- The design has a purity that is quite amazing
- Effortless power
- Soundstage is big
- Transparent
Product Considerations
- Not necessarily suitable for pairing with extremely cold sounding, sterile or bright speakers
Comparisons (according to reviewers)
- MC3500 is more open and airy, with base not as hard fisted, compared to Krell KSA 250
- It compares with brands like soulution, big Audio Research, and CH Precision, but at a lower cost
Takeaway: The MC3500 is an impressive amplifier that delivers a natural and pure sound, able to drive almost any speaker. If you're in the market for a McIntosh amp, this is the one that makes music sound pure, simple and unadulterated.
Video review
Our take on the brand
What else competes at this price?
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Our Summary
Product Strengths
- Impressive bass response, dynamics, and power for a 12-Watt single-ended tube amplifier
- Dense, tactile, and sweet harmonic color with a clean and clear sound
- Robust build quality with point-to-point hand wiring and exceptional parts
- Easy biasing with a switch for KT88 to KT120/150 mode
- Proprietary transformers that contribute to a flatter response and deeper low bass
Product Considerations
- Careful speaker matching is required, ideally with speakers that have at least 94dB/W efficiency and a stable speaker load
- Must be turned off for at least 10 minutes, preferably 30, before turning it back on, or the rectifier tube could blow
- The correct tube type must be selected on the back of the amp, otherwise performance could be lackluster or tubes could be damaged
- The XLR input involves a slight reduction in detail due to using an input transformer to convert the incoming balanced signal to single-ended
Comparisons (according to reviewers)
- The Bryce eliminates the shortcomings of ampsandsound Nautilus when used as a speaker amplifier, adding dynamics, bass, and an extended top end
- The Bryce monoblocks are more romantic in execution, with single-ended construction—compared to the push-pull output of ampsandsound Zion
Takeaway: The Bryce Monos are high-quality amplifiers with a surprisingly powerful and detailed sound, providing an engaging listening experience. They are great for audiophiles looking for a tube amp that delivers both emotional connection and technical performance.
Video review
Our take on the brand
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Our Summary
Product Strengths
- Simplicity mixed with extreme refinement delivers something special that is unforgettable
- Amazing bass control, even over speakers with notoriously floppy bass
- Solid-state quiet, with no noise or hum present even with ears pressed up to the speakers
- Calmly pulls one into the presentation, taking one further into the music
- Excels with music featuring a lot of inner detail or acoustic instruments, resolving textures and attacks with precision
- Sheer physical quality, both inside and out, is the best of the best
Product Considerations
- If new to the 300B tube, note these tubes have no central locator pins like other power tubes, one can put these tubes in their sockets wrong and blow the amplifier up
- Requires no setup other than installing the tubes
Comparisons (according to reviewers)
- Attention to detail is not seen on a McIntosh
- Only the BAT REX Power Amplifier delivers bass grip and resolution at the same level
Takeaway: The ampsandsound Black Pearl amplifier offers a unique and immersive listening experience with exceptional detail and bass control. It is a destination product worth the investment for those who truly appreciate high-quality audio.
Video review
Our take on the brand

Our Summary
Product Strengths
- Pure sound, free of coloration while retaining musical detail, allows a graceful and effortless listening experience
- Natural and tangible sound due to accurate reproduction of details, creates a believable presentation
- Solid and controlled bass performance, unusual for a 300B single-ended triode amplifier
- Excellent sense of touch and tactile sound, making instruments like plucked strings and bowed violins sound very convincing
- Wide and deep soundstage with good 'air', providing a transparent and 'hear-through' sound, especially with complex music
Product Considerations
- Careful matching with partnering equipment is required, especially speakers with high efficiency
- Relatively low overall gain requires a source with a high output voltage
- Output transformer links need to be correctly set for speaker impedance, requiring dealer assistance
- Some reviewers found the top end sounding a bit rolled off before use of appropriate high efficiency speakers and source gain settings
- Changing the EL803S driver valves requires carefully matched pairs supplied by Thöress
Comparisons (according to reviewers)
- Vs Shindo Haut-Brion/Corton-Charlemagne, Thöress has more treble extension and transparency, Shindo has better upper-bass/lower-midrange substance and body—and more drive
Takeaway: The Thöress SE-300B offers a supremely musical and detailed listening experience with a focus on accuracy and sonic purity. When paired with the right speakers, this amplifier could be an excellent choice to bring out the best in music.
Video review
Our take on the brand

Our Summary
Product Strengths
- The EHT combines tubes and transistors to mate the most desirable characteristics of both
- Amplifiers provide fullness and density, even at low listening volumes
- The EHT creates a natural sound with incredible saturation
- They are fully short-circuit proof at the outputs without any sound-degrading protection
- A switch-on delay is omitted because switching on/off develops no disturbing noise or dangerous signal in this circuit
Product Considerations
- Sound is focused on timbre rather than detail
- Their sound is soft rather than focused, rather warm than open, and rather close to us than presented in a perspective
- The devices are quite large, as they measure 434 x 184 x 434 mm (W x H x D) and weigh 14 kg each
Takeaway: The Thöress EHT monoblocks offer a holistic view of the musical material and its reinterpretation that can be very enjoyable for long listening sessions. They create events in their own acoustic environment, which is completely transferred to the listening room, creating a beautiful, organic, comprehensive, and internally properly arranged sound for those who value tonality above all else.
Video review
Our take on the brand

Our Summary
Product Strengths
- Delivers an incredibly rich, flavorful midrange and a sweet, relaxed treble
- Has a more sophisticated presentation than the utilitarian bent-metal chassis sported by most integrated tube amps on the market, and the smooth lines of the chassis help the amp stand out from the crowd
- Has a clever tube cage design with a clear Plexiglass front panel that delivers an unobstructed view of the tubes and is easy to install and remove
- Is seriously quiet, and there was effectively zero noise through any of the speakers
Product Considerations
- Can sound wildly different, depending on the impedance of the speakers
- The four slightly squishy feet underneath the amp may cause stains
- The power switch is on the rear of the chassis, which may be problematic if installing the amp in a cabinet with limited access
- Needs a good 20 minutes to warm up, and on initial startup, the amp sounded a bit thin, bright, and constipated, but after one album, it opened right up
- Limited power output (15Wpc) may not be sufficient for all speakers or listening preferences, especially when wanting to play music very loud
Takeaway: The Fezz Audio Lybra 300B is a well-designed tube amplifier that delivers a rich and flavorful sound. It can bring out the best in your speakers, offering clarity and great sound.
Video review
Our take on the brand
Note that this is a discontinued product. You may want to visit the brand's page here to browse their newer products.
What reviewers think
Magazine reviewers and YouTubers have tried this product—so we've summarized their strongest opinions below.
Want to see more similar products?
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