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
Bloggers and YouTubers have tried this product—so we've summarized their strongest opinions below. Links to full reviews follow.
All
ZoneMaster ZM12
reviews
Manufacturer details
- Power Output Zone 1: 120 watts x 2 @ 8Ω, 150 watts x 2 @ 4Ω or 2Ω
- Power Output Zone 2-6: 60 watts x 10 @ 8Ω, 100 watts x 10 @ 4Ω or 2Ω
- Minimum Speaker Impedance: 2Ω
- Frequency Response: 20 Hz - 20 kHz, +0/-0.25 dB, 5 Hz - 50 kHz, +0/-3 dB
- Total Harmonic Distortion: < 0.05% at typical listening levels, < 1.0% at full power
- Interchannel Crosstalk: 70 dB at 20 kHz
- Total Gain: 29 dB
- S/N Ratio: >112 dB
- Power Consumption: 1550W max, 150W typical, 55W idle (all zones), 15W idle (one zone), 0.5W standby
- Dimensions: 17.25" (437 mm) W x 14.5" (369 mm) D x 4.15" (105 mm) H
- Weight: 21 lbs (9.5kg) net, 27 lbs (12.2kg) shipping
Brand highlights
Taking a step back to look at reviewers' thoughts of the brand's entire lineup—not just this product—what stands out most is the following:
- Parasound partners with legendary designer John Curl to create high-performing, reliable audio equipment known for its exceptional value.
- The brand meticulously selects high-quality components to minimize noise and distortion, often using parts that are no longer widely available, demonstrating a commitment to sonic neutrality.
- They offer versatile products with extensive input/output options, including unique features like adjustable subwoofer crossovers and gain matching capabilities.
- Parasound carefully balances high power output with finesse, resulting in a sound signature that is both dynamic and easy to listen to for extended periods.
Select products
HALO A23+
- Positioning: The entry-level power amplifier in Parasound's lineup.
- Description: Offers a compelling audio experience with its high bias Class A/AB operation, delivering 160 watts per channel into 8 ohms. It stands out with its direct-coupled design, which maintains signal purity and enhances transparency, unlike the more powerful A21+ which offers higher wattage and larger transformer capacity. This makes it ideal for smaller rooms or those on a tighter budget who still want high-quality sound.
HALO HINT6
- Positioning: An integrated amplifier that combines preamp and power amp functions in one unit.
- Description: Provides high-end performance with 160 watts per channel into 8 ohms, featuring a Burr Brown analog resistor ladder volume control for precise adjustments. It offers more connectivity options and a built-in DAC compared to the A23+, making it suitable for users needing an all-in-one solution with digital inputs and phono stage for vinyl enthusiasts.
HALO A21+
- Positioning: A mid-tier power amplifier offering more power and features than the A23+.
- Description: Delivering 300 watts per channel into 8 ohms, the A21+ is designed for those seeking more power and dynamic range. It features a larger transformer and higher filter capacitance than the A23+, providing better performance for larger rooms or more demanding speakers.
JC5
- Positioning: A high-end stereo power amplifier in the Parasound lineup.
- Description: Combines the power of monoblocks in a stereo amplifier, delivering 400 watts per channel into 8 ohms. It offers ultra-high bias Class A/AB operation, providing a more refined sound compared to the A21+, with a dual-mono design for superior channel separation.
JC1
- Positioning: The flagship monoblock power amplifier in Parasound's lineup.
- Description: Represents the pinnacle of Parasound's engineering, delivering 450 watts into 8 ohms with the first 25 watts in pure Class A. It features Bybee Music Rails for noise reduction and a custom R-core transformer, offering unmatched power and precision compared to the JC5. This groundbreaking amplifier makes it perfect for the most discerning audiophiles with large budgets and high-performance loudspeakers.
Our take on the brand
Look inside the brand
Our interview with the brand
What are two key technological innovations or strong opinions that differ you from other brands?
What's your approach to customer support?
What are your favorite tracks for showcasing the strength of your products?
What other products pair best with yours?
Used
Parasound
What if you spend more?
Our summary
Product Strengths
- Delivers amazing quality of sound and detail
- Bulletproof amplification
- Has a rhythmically soulful sound with a tremendously rich and natural midrange
- The A51's bass is well-defined, extremely textured, and robust
- With 250 watts on tap, the Parasound A51 will power virtually anything
Product Considerations
- Due to its class A/AB design, the A51 does get a bit warm and should be installed in a properly ventilated space and/or rack
- The A51 is large and heavy, and is best moved and/or positioned by two people
Comparisons (according to reviewers)
- Compared to Rotel, the Rotel makes the M&K Sound system slightly bright with a bit of sibilance, while the Parasound is more neutral
- Compared to Acurus A250, the Parasound had tighter bass, which is probably attributed to a better damping factor
Takeaway: The Parasound Halo A51 is a high-performance amplifier with great sound quality, detail, and build quality, making it an excellent choice for audiophiles and home theater enthusiasts. Its ability to deliver power and control to speakers makes it a valuable addition to any high-end audio system.
Video review
Our take on the brand
Circuitry designed by legendary John Curl
Ultra-high bias Class A/AB operation
Stable with speaker impedance dips below 1Ω
Bybee Music Rails™ - active high frequency filters for input stage
New John Curl driver stage employs a cascode circuit for greater open loop bandwidth & superior linearity
Gain switch to select 29 dB or 23 dB gain for optimum compatibility with high gain preamps or extremely efficient speakers
R-core transformer for input stage suppresses noise on power line
6 massive 33,000 uF Nichicon Gold Tune filter capacitors for output stage
22,400 uF input stage power supply filter capacitors, independent of the main power supply
CHK Infinium, custom 5-way speaker binding posts for easy bi-wiring
Neutrik locking XLR balanced input & loop output jacks
Vampire 24k gold-plated RCA input & loop output jacks
Direct-coupled signal path, no capacitors or inductors in the audio path
JFET input stage, MOSFET driver stage
24 beta-matched 15 ampere, 230V, 60 MHz bipolar output transistors
Independent power supplies for input stage, driver stage & output stage
Full power is rated all the way down to 2Hz for unrestricted low-end bass
Harris hyper-fast soft-recovery bridge diode rectifiers
REL & Nichicon Muse capacitors
DC servo & relay protection circuits
AC turn-on inrush surge protection with relay bypass
Automatic turn-on by 12 V trigger or audio sensing
2 rack space chassis with rear carry handles
Available in black
Product Strengths
- Impressive parts quality uses FR408 circuit boards and an R-Core transformer to suppress power line noise
- The amplifier has a harmonic richness and bloom to the sound that's seductive
- Bass was tight, controlled, very extended with pitch definition and detailed
- The amplifier's ability to resolve low level spatial cues is amazing—sound stage layering, image specificity, size and shape are outstanding
- Excellent build quality includes a heavy duty chassis and heat sinks
Product Considerations
- It is only available in black
Comparisons (according to reviewers)
- The JCM250s give a performance very similar to Cambridge Audio JC1 Plus
- The JCM250 is a bit warmer than the Cambridge Audio Edge M, and includes controls to set bias and gain
- With the JCM250 monoblocks having a separate power supply for each channel, it has lower noise compared to the Cambridge Audio JC5
Takeaway: The JCM250 is a high-quality amplifier that uses the best components. It offers great versatility, fitting well with any preamp and speakers.
Video review
Our take on the brand
The A35.8 is Primare’s most powerful and flexible multi-channel amplifier, designed to serve the needs of virtually any high-performance multi-channel system through its ability for each pair of channels to be bridged to mono for an incredible level of power delivery and system building options, including 1500 watts of total output in a fully bridged bi-amped stereo configuration. Shipping June 2022!
Our summary
Product Strengths
- The A35.8 provides eight channels of 'unimpeachable Class D power in a fairly compact and very flexible package'
- Flexible configuration options for power output to speakers are available, such as bi-amping and bridging
- Each stereo pair can be bridged separately to make four times 375 watts (8 Ohms) from the eight times 150 watts
- Fault-free sound quality
- High quality fit and finish
- The A35.8 offers flexible connectivity options
Product Considerations
- The 20-amp power inlet is the seldom-seen variety with three horizontal blades
- The speaker output posts are spaced too widely for dual-banana plugs
- Cabling can be tricky
- A high current power cord is needed
- Lower gain is present, though this doesn't necessarily need to be an issue
Comparisons (according to reviewers)
- Vs NAD M28, the A35.8 gets you one more channel and more versatility for a 10% price increase
- Vs Benchmark AHB2, the Benchmark presented a more neutral tonal balance and undistorted soundstage
- Vs NAD C 298 stereo amplifiers, the Primare seemed slightly more forward, often conveying an appealing liveliness
Takeaway: The A35.8 power amplifier is a flexible and versatile product worth considering for anyone seeking a high-quality multi-channel setup. Its ability to bridge channels offers many ways to configure your speaker system.
Video review
Our take on the brand
Our summary
Product Strengths
- The EAR 890 produces 70Wpc in stereo, and can be bridged to 140W in monoblock
- Neutral sound that gets out of the way and lets the user enjoy the music
- Complex and dense music textures are handled with ease, and dynamically demanding passages are sailed through
- Articulate midrange
- Detailed and realistic bass
Product Considerations
- Removing/installing tube cages is difficult and time-consuming
- The loudspeaker binding posts are positioned too close to the output transformers, making it hard to tighten them properly
- Some assembly work appeared amateurish, specifically the use of silicone in various locations, such as fastening chassis wires
- The amplifier can operate quite hot
- May not have as much bass impact compared to solid state amps
Comparisons (according to reviewers)
- The EAR 890 monoblocks achieve SET-like definition along with the authority and swagger necessary for most full-size speaker systems, when compared to Cary Audio 300B SET amps
- The EAR 890 is as textured as the top LAMM designs, but with noticeably better neutrality and more power
- The EAR 890 surpassed the deHavilland KE50As with a more articulate midrange, producing more color and separation in the microtones of instruments
Takeaway: The EAR 890 is easy to set up and sounds good with very little tweaking, making it easy to just sit back, relax, and enjoy the music. It's a good choice for people who want a tube amp that is both musical and powerful for their home listening experience.
Video review
Our take on the brand
What competes at this price?
Our Summary
Product Strengths
- Delivers ample, clean, and dynamic power to all channels, ensuring speakers reach their full potential
- Designed by John Curl, featuring Class A/AB circuitry for a balance of warmth, richness, efficiency, and punch
- Pleasing sound for dialogue and music, with very high-quality and detail
- Versatile, suitable for both movies and music, with a low noise floor for quiet passages and great transparency—that doesn't color the sound
- Built to last, with high-quality internal components
- Signal-sensing power-on mode can be fussy and may require adjustment
Product Considerations
- Super heavy and large, potentially requiring rearranging a system or dedicated rack space
- Only available in anodized black
Comparisons (according to reviewers)
- The A52 Plus has bigger parts and bigger power than the Outlaw Model 5000, including balanced XLR connections
- A52 Plus is the 'teenager' compared to the elder Parasound A51
- Parasound A52+ sounds better, is more accurate, and more powerful than the Denon receiver's amplifier section
Takeaway: The Parasound A52+ Halo is a versatile and powerful amplifier that delivers clean, dynamic sound for both home theater and music systems, with a build quality designed to last. This is a worthy investment for audiophiles and home theater enthusiasts who seek high-quality audio performance.
Video review
Our take on the brand
Our Summary
Product Strengths
- The M23's build quality feels solid and elegant, with impressive small design details
- The sound is striking in its purity and clarity
- It offers up to three levels of gain, switchable on the back panel, to best fit the system
- It provides a clear sound without sounding hard
- It features Purifi Eigentakt Class D amplification, which provides virtually unmeasurable distortion levels
Product Considerations
- The bass is clean but may be perceived as a little on the cool side and not as 'wompy-sounding'
- The M23 is not a forgiving amplifier that makes everything sound sweet and wonderful—it's not for those seeking a soft and mellow sound
- Bridging with speakers below 5 or 6 ohms is not recommended, as the amp will current limit and potentially shut down
- The reviewer found ergonomical challenges using fancy speaker cables in bridged mode due to wide terminal spacing
- The capacitive touch power button can accidentally trigger
Comparisons (according to reviewers)
- Vs Bel Canto C6i: The M23 offered a layer of refinement and better reproduction of the recording space
- Vs Pass XA25: The M23 had more transparent sound and detail, especially in the treble and upper mids, but lacked the organic quality of the XA25
- Vs HiFi Rose RS 520: The M23 sounded cleaner and had better separation/depth, HiFi Rose seemed to have an EQ built-in, emphasizing midrange and bass
- Vs NAD C298: The M23 is more neutral, deals with decay more naturally, and has better casework, making it look high-end
- Vs Anthem M1 monoblock amplifiers: The M23 was slightly more transparent throughout the entire frequency range
- Vs Bryston 4B 3: The Bryston had more grunt but the M23 is more neutral
Takeaway: The NAD M23 is a powerful and precise amplifier that delivers clean and clear sound, making it a great choice for audiophiles who want to hear their music as accurately as possible. It is especially well-suited for those looking to build a high-end system around a quality preamp or DAC.
Video review
Our take on the brand
Our Summary
Product Strengths
- Exceptionally transparent sound output quality
- Exceptionally powerful, capable of outputting 500W into a 4-Ohm load
- Delivers a remarkably clean, transparent sound with very little noise or distortion
- The amplifier's ability to reproduce bass is awe-inspiring and delivers deep, powerful bass without distortion
- Runs cool and weighs very little for its sound output, making it easy to move around
Product Considerations
- Options can be a little pricy, such as the 12v trigger and RCA inputs
- The Starkrimson Stereo Ultra may lead to further system upgrades
- Depending on your sources, the Starkrimson Stereo Ultra will play exactly what you feed it, good or bad, and if your source components are slow, the Starkrimson Stereo Ultra will not speed them up
- Power on only after all connections are properly made, including the power cord, analog inputs, and speaker outputs, and wait five minutes after powering it off before removing any of the connections
Comparisons (according to reviewers)
- Compared to the Krell S550i integrated amp, the Starkrimson Stereo Ultra showed a much faster and finer resolution of the upper frequencies of the human voice and a far greater ability to play more of the microdetails of a recording
Takeaway: The Starkrimson amplifier is well-built and provides a level of speed and transparency to hifi music that makes listening to music very fun. Its GaN modules can be upgraded and it is available in several configurations.
Video review
Our take on the brand
Our Summary
Product Strengths
- A lovely, lush sounding performance that's hard to dislike and sounds smooth but far from lifeless, delivering high levels of detail in a cohesive and musical manner
- A sympathetic performer, it prefers to play to its inferior partnering equipment's strengths than overly expose their weaknesses, as many hifi audio examples tend to do
- It can cater for a wide range of headphones and connections and it is a benchmark product that's highly recommended
- Zero musical flaws to report and is nearly perfect in execution
- A stunning design to the eye and ear, it is overall a wonderful addition for the perfectionist who wants the very best performance at home or even in the studio
Product Considerations
- The volume control operation lacks linearity, making it hard to make subtle changes in level
- No input selector, so one should only connect one type at once
- On some samples, the volume control is loose and wiggles in its chassis housing
- The octal AC socket is a bit of an odd choice, considering most users might prefer IEC
- The depth, snap and weight of the low end was dynamic and exciting on some recordings and less than stellar on others
Comparisons (according to reviewers)
- Vs Musical Fidelity M1 HPA—the MHA200 has a lush warmness to the music that brings strings to life in a way that makes the M1 HPA sound somewhat sterile in comparison
- Vs EAR Yoshino HP-4 reference—the MHA200 was a touch brighter than the reference, though only slightly
Takeaway: The MHA200 is an enjoyable product with a rich, balanced, and powerful sound, that's more forgiving than most rivals and can be enjoyed for years to come. This headphone amp is perfect for personal listening, design, and operation that will work its magic.
Video review
Our take on the brand
Our Summary
Product Strengths
- Excellent build quality
- Clean and clear sound delivery
- Wide and precise soundstage with astounding bass power that's remarkably tight and tuneful
- Speakers can sound as if they're coming from outside the room, creating a holographic soundstage
- The S300+ can power basically any speaker
Product Considerations
- Runs hot, especially in high bias mode
- Somewhat heightened noise floor that presents as a light 'hiss'
- Bright power LED can be distracting in a dark room
- High gain may not be suitable for high sensitivity speakers
- Lacks any kind of volume control
Comparisons (according to reviewers)
- Vs Jadis Orchestra Reference—the S300+ wins in clarity, soundstage, instrument separation, and distortion level
- Vs Burson Funk—the S300+ sounds far cleaner, more detailed, and has better dynamics, resolution, and transparency
- Vs Cyrus One Cast—the S300+ sounds far more controlled, more dynamic, and punchy; the bass is tighter; the treble is crisp and airy; and the midrange is sweeter and more vivid
Takeaway: The KECES S300+ is a well-built and powerful amplifier that delivers a clean, detailed, and engaging sound for a variety of speakers. It is worth a try for those seeking a top-performing amplifier.
Video review
Our take on the brand
How to buy
Amplifiers
Search all hifi products
Explore our database of 10,000+ new and 25,000+ used hifi products.


































































