Fosi Audio ZH3 DAC Headphone Amp Preamp

Premium Versatility: Balanced DAC, Headphone Amplifier, and Preamp in One Elegant Package

The headphone amplifier market continues to evolve rapidly, with increasingly sophisticated features and performance becoming available at more accessible price points. Fosi Audio has established itself as a company that consistently delivers exceptional value, and their ZH3 DAC/Headphone Amp/Preamp is perhaps their most impressive offering yet. Combining a high-quality DAC, powerful balanced headphone amplifier, and versatile preamp functionality in one compact chassis, the ZH3 represents a complete solution for headphone enthusiasts and those looking to build a flexible audio system.

At $179 (before typical Amazon discounts), the ZH3 enters a competitive market segment where it faces stiff competition from established brands. But having listened to it for a week or more now and comparing it with many other headphones amplifiers, I think the ZH3 is an exceptionally pragmatic choice for those wanting an all round excellent headphone amplifier at a very good price point.

But before I get into the technical details of the ZH3, let’s look at the unboxing:

Unboxing and Build Quality

The Fosi Audio ZH3 arrives in an attractive, professional-looking package that hints at the quality inside.

The outer sleeve displays clear specifications and product information, giving a good overview of the ZH3’s capabilities.

Removing the sleeve reveals a sturdy inner box that protects the contents well.

Opening the box, you’re greeted with the ZH3 unit and user manual on top.

Further unpacking reveals the ZH3 itself, nestled securely in custom foam inserts.

The complete package includes:

• Fosi Audio ZH3 DAC/Headphone Amp/Preamp
• Remote control
• Power adapter
• USB cable (with a thoughtful pull-tab for easy removal)
• USB adapter
• 6.35mm to 3.5mm audio adapter
• Trigger cable
• User manual

The usb cable has a nice ‘grabber’ that allows it to be easily removed from the unit:

My review unit came with a special anniversary dial, which adds a touch of distinction to the already attractive front panel.

The ZH3 features a solid aluminum chassis that exudes quality.

The front panel is elegantly designed, and this is what it looks like with the special anniversary dial:

The build quality is excellent throughout, with attention to detail evident in everything from the smooth action of the volume control to the solid feel of the input selection buttons. The chassis provides adequate ventilation while maintaining a sleek, premium appearance that would complement any audio setup.

Features and Connectivity

The Fosi Audio ZH3 is remarkably well-equipped in terms of both inputs and outputs, making it a versatile centerpiece for a wide range of audio systems.

Front connections

Obviously, the ZH3 as a headphone amplifier has both 4.4mm and 6.35mm outputs, which are well-suited for most headphones. The box also included an 6.35mm to 3.5mm audio adapter, so most headphone cable connections are covered, though I would have loved to have also see an XLR headphone output also.

Display

This is one of the most impressive features of the ZH3 as this round display is very nicely implemented and is impressively visible from a distance. Here is a little video showing the various menu options available with the ZH3:

You control the menu using either the remote control or the front power dial.

Input Options

The rear panel reveals an impressive array of digital and analog inputs:

• USB input (supporting up to 32-bit/768kHz PCM and DSD512)
• Optical input (supporting up to 24-bit/192kHz PCM)
• Coaxial input (supporting up to 24-bit/192kHz PCM)
• RCA line-in (for analog sources)

As I mentioned earlier, I liked the usb-c cable:

This comprehensive selection allows the ZH3 to serve as a hub for virtually any digital or analog source you might want to connect. The high-resolution capabilities of the USB input are particularly impressive, supporting the latest high-res audio formats.

Here are the bitrates when connected to my MacBook Pro via usb:

Output Options

The output side is equally well-equipped:

• 4.4mm balanced headphone output
• 6.35mm single-ended headphone output
• RCA line outputs
• XLR balanced outputs

This range of outputs makes the ZH3 exceptionally versatile. You can use it solely as a headphone amplifier, as a DAC/preamp feeding a power amplifier, or both simultaneously. The inclusion of balanced outputs for both headphones and line-level connections is a premium feature that’s rare at this price point.

Additional Connectivity

The ZH3 also includes a 12V trigger input/output for synchronizing power with other components and the ZH3 comes with a trigger cable:

And AC power input (via the supplied adapter). Here is the specs on the back of the supplied adapter:

The trigger connections are a thoughtful addition that allows the ZH3 to be integrated into a more complex audio system where components power up and down in sequence.

Remote Control

The ZH3 comes with a full-function remote control that provides convenient access to all key functions:

The remote allows for input selection, volume adjustment, and muting, making it easy to control the ZH3 from your listening position. This is particularly useful when using the unit as a preamp in a larger system.

The Fosi Audio Ecosystem

One of the strengths of Fosi Audio’s approach is the ability to build a complete audio system using their complementary components. The ZH3 works seamlessly with other Fosi Audio products, creating a cohesive and high-performance audio chain.

For this review, I tested the ZH3 in several configurations within the Fosi Audio ecosystem:

• As the central hub in a complete Fosi Audio stack with the ZP3 (Preamp), ZD3 (DAC), and GR70 preamp
• Feeding a pair of V3 Mono monoblock amplifiers connected to Fosi Audio SP601 speakers
• And of course with the Fosi Audio i5 Headphone

This level of integration demonstrates the thoughtful system design approach that Fosi Audio has taken, ensuring their products work together harmoniously while each maintains its distinct purpose and value proposition.

In fact, I thought it was interesting that Fosi Audio will be releasing a Streamer (as I did use a WiiM Pro as a digital source for the ZH3) and a Subwoofer (as I used a KEF Kube10 subwoofer), so pretty soon those two missing elements of a full audio stack will also be provided by Fosi Audio.

Technical Specifications and Measurements

The Fosi Audio ZH3 boasts impressive specifications that reflect its high-performance capabilities:

General Specifications

• Chipset: XMOS XU316+AKM4493SEQ+ OPA1612 x 4
• Input: Coaxial, Optical, USB, RCA
• Output: 4.4mm, 6.35mm, RCA, XLR
• Headphone Impedance: 16-300Ω
• Maximum Sampling Rates:
  • USB: PCM 32bit/768kHz, DSD512
  • OPT: PCM 24bit/192kHz
  • COAX: PCM 24bit/192kHz
• Power Input: DC 12V

Fosi Audio have provided a nice diagram showing the internal components of the ZH3:

4.4mm Balanced Headphone Output

• Max Output Power: 2570mW x 2（32Ω/THD+N＜1%)
• SNR: ≥ 119 dB
• Dynamic Range: ≥ 119 dB
• THD: ≤ 0.00018%
• Noise Floor: ≤ 4.9μV

6.35mm Single-Ended Headphone Output

• Max Output Power: 640mW x 2（32Ω/THD+N＜1%)
• SNR: ≥ 121 dB
• Dynamic Range: ≥ 121 dB
• THD: ≤ 0.00024%
• Noise Floor: ≤ 1.9μV

Measurements

For those interested in objective performance metrics, the Fosi Audio ZH3 was thoroughly measured by Amir at AudioScienceReview. I encourage readers to check out the full review at AudioScienceReview.

The balanced headphone output measurements show excellent performance:

The power output measurements are equally impressive, showing the ZH3’s capability to drive demanding headphones:

These measurements confirm the ZH3’s excellent performance, with very low distortion, high signal-to-noise ratio, and ample power output. The balanced output in particular shows exceptional performance, with a SINAD over 113dB and power output approaching 2.5 watts into 32 ohms, more than enough for almost everything including the most demanding headphones.

Sound Impressions

The Fosi Audio ZH3 delivers exceptional sound quality that belies its modest price point. Its implementation of the AKM4493SEQ DAC chip and OPA1612 op-amps results in a transparent, detailed, and engaging presentation that works well with a wide variety of headphones and musical genres.

For my subjective testing, I used several headphones including Hifiman Ananda, Sennheiser HD600, Fosi Audio i5, FiiO FT7, and Meze 105 Silva. This variety allowed me to assess the ZH3’s performance with different impedance loads and sensitivity levels.

Bass

The bass reproduction through the ZH3 is tight, controlled, and extends deep with excellent definition. There’s no bloat or muddiness, just clean, articulate low frequencies that provide a solid foundation for the music.

Listening to James Blake’s “Limit to Your Love” through the Hifiman Ananda, the sub-bass drops were rendered with impressive depth and control. The ZH3 maintained composure even during the most demanding passages, delivering the physical impact of the bass notes without sacrificing detail or allowing them to overwhelm other elements of the mix.

Midrange

The midrange is where the ZH3 truly shines, particularly with higher impedance headphones like the Sennheiser HD600. Unlike tube amplifiers such as the Fosi Audio GR70 (which can alter frequency response with different headphone impedances), the ZH3 maintains a transparent, neutral presentation that allows the natural character of the headphones and recordings to come through.

On Norah Jones’ “Don’t Know Why,” the ZH3 reproduced her vocals with exceptional clarity and natural timbre. The delicate piano notes had proper weight and decay, demonstrating the ZH3’s ability to maintain the integrity of complex harmonic structures without adding coloration.

Treble

The high-frequency performance is extended and airy without any harshness or brightness. On Diana Krall’s “Temptation,” the cymbal work was rendered with natural texture and decay, avoiding the metallic edge that lesser amplifiers can impart.

The ZH3’s clean, transparent nature ensures that treble detail is presented without exaggeration or suppression. This balanced approach makes for fatigue-free listening even during extended sessions with treble-forward headphones.

Soundstage and Imaging

The ZH3 creates an impressively wide and deep soundstage with precise imaging. On orchestral recordings like Mahler’s Symphony No. 2 performed by the London Symphony Orchestra, instruments were placed with excellent specificity within the soundstage, creating a three-dimensional presentation that enhances the listening experience.

The balanced output in particular seems to provide a slightly wider soundstage and more precise imaging compared to the single-ended output, though both are excellent.

IEM Performance and Noise Floor

A crucial test for any headphone amplifier is how it performs with highly sensitive in-ear monitors (IEMs), which can reveal noise floor issues and gain matching problems that might not be apparent with less sensitive headphones.

I’m pleased to report that the ZH3 performed admirably with high-sensitivity IEMs. Even on low gain, I could not detect any audible noise floor, which is impressive for an amplifier with this much power on tap. This makes the ZH3 a versatile choice for those who switch between power-hungry over-ear headphones and sensitive IEMs.

The absence of background noise or hiss, even with the most sensitive IEMs, speaks to the quality of the design and implementation of the amplification stage in the ZH3.

Comparisons with Other Headphone Amplifiers

To put the Fosi Audio ZH3 in context, I compared it with several other headphone amplifiers in my collection:

Below is a comparison of key specifications for the Fosi Audio ZH3 and its competitors:

FiiO K15

The FiiO K15 (US $549) is a well-regarded DAC/amp with higher power capabilities than the ZH3. With 3000mW of balanced output power and support for both internal AC power and external linear DC power, the K15 is a powerful option. Despite its higher price point, the ZH3 still offers excellent connectivity options and system integration at a more affordable price. The ZH3 provides great value with a substantial build quality and a versatile feature set as a system hub.

FiiO K17

At a significantly higher price point than the ZH3 (US $899), the FiiO K17 offers more power with its 4000mW balanced output and fully-discrete Class AB amplification. The ZH3 provides a neutral sound presentation and excellent connectivity options at a much lower price point. The K17’s premium design and high-end components justify its higher price, but the ZH3’s excellent build quality and preamp capabilities make it a more budget-friendly option for system integration.

Topping DX5 II

The Topping DX5 II is a powerful competitor at $299, offering significantly more power than the ZH3 with its impressive 7600mW balanced and 2600mW single-ended outputs. The DX5 II represents exceptional value and includes features like VU meters and a 10-band PEQ. While the ZH3 cannot match the raw power output, it offers a competitive feature set at a lower price point with excellent sound quality.

JDS Labs Element IV

The Element IV costs significantly more than the ZH3 at $549 but offers the advantage of a built-in 12-band parametric EQ and substantial power output (3200mW per channel). Its iconic volume knob and US-built quality are notable features. In terms of raw sound quality, the ZH3 holds its own remarkably well considering it costs less than half the price of the Element IV.

Burson Playmate 3

The Playmate 3 (Standard version ~ US $599, Deluxe ~ US $999) has a notably warmer sound signature with its Class-A design, compared to the ZH3’s more neutral presentation. With approximately 3W per channel in Class A operation and an idle bias of ~30W, it offers significant power for demanding headphones. It also provides opamp rolling capabilities for sound customization and uses high-quality discrete components. While the Playmate 3 might appeal to those seeking a warmer sound and are willing to pay the premium price, the ZH3 provides better value with solid technical performance at less than half the price of even the standard version.

Aune N7

The Aune N7 (EUR 429 including VAT in many EU countries) is a fully discrete Class-A amplifier with output power up to 6.5W into low impedance loads. It features both 6.35mm single-ended and 4.4mm balanced outputs. Despite the N7’s premium build and impressive power specifications, the ZH3 offers better value at a lower price point. The ZH3’s feature set is more comprehensive despite costing significantly less than the N7.

SMSL DO400 and C200 Pro

The SMSL offerings provide good alternatives with quality DACs, but with different value propositions. The DO400 (~ US $499 in many markets) offers impressive power specifications: 6.0W/channel at 16Ω, 3.0W at 32Ω, ~700mW at 300Ω, and ~350mW at 600Ω, along with a fully balanced design and very low distortion. The C200 Pro, on the other hand, is surprisingly affordable at US $ 199 (sometimes ~US $180 during deals) while still delivering about 3W × 2 at 16Ω and detailed power scaling across impedance ranges with an output impedance “near 0Ω.” The ZH3 sits between these options price-wise while offering a comprehensive feature set that competes well against both.

Schiit Midgard

The Schiit Midgard (US $219 standard price in US) represents excellent value with impressive power specifications: ~5.5W RMS per channel at 16Ω, ~4.8W at 32Ω, ~3.2W at 50Ω, ~750mW at 300Ω, and ~375mW at 600Ω. It offers both balanced and single-ended outputs with two gain levels, very low distortion, and good headroom. While similarly priced to the ZH3, the Midgard is purely an amplifier, whereas the ZH3 offers the added functionality of a built-in DAC and preamp capabilities, making it a more versatile all-in-one solution for those who need those features.

When choosing between these amplifiers, the decision often comes down to specific feature requirements (PEQ being something worth paying for), power needs, aesthetic preferences, and system integration requirements. The ZH3 distinguishes itself with its excellent balance of performance, features, and value, making it a compelling choice for many listeners, particularly those who want a versatile, high-performance unit without spending $400-600.

Rating Explanation

The Fosi Audio ZH3 earns a well-deserved 5-star pragmatic rating for several compelling reasons:

• Exceptional Value: At $179 (and often less with common discounts), the ZH3 delivers performance and features typically found in much more expensive equipment.
• Versatility: The combination of high-quality DAC, powerful balanced headphone amplifier, and preamp functionality makes it an extremely versatile component that can serve as the heart of various audio systems.
• Technical Performance: The ZH3’s excellent measurements and subjective sound quality place it among the top performers in its price category and beyond.
• Build Quality: The solid construction, quality components, and thoughtful design details reflect a commitment to long-term reliability.
• Feature Set: The comprehensive input/output options, remote control, and compatibility with a wide range of headphones make it a future-proof investment.

The only minor complaint I have concerns the volume control, which can be somewhat sticky for fine-tuning with manual adjustment. However, this is easily addressed by using the remote control, which allows for precise volume adjustments. Unlike the issue with the ZP3 preamp’s volume control (which was a more significant concern for a preamp), this minor quirk doesn’t detract from the ZH3’s overall excellence as a headphone amplifier.

The ZH3 is ideal for:

• Headphone enthusiasts who own multiple headphones with varying power requirements
• Audiophiles building a versatile system that can accommodate both headphone and speaker listening
• Users who appreciate clean, transparent sound without coloration
• Those looking for a complete solution that eliminates the need for multiple separate components

Conclusion

The Fosi Audio ZH3 DAC/Headphone Amp/Preamp represents exceptional value in today’s audio market. By combining a high-quality DAC, powerful balanced headphone amplifier, and versatile preamp functionality in one well-built chassis, Fosi Audio has created a compelling all-in-one solution that punches well above its price point.

For anyone looking to build or upgrade a headphone-centric audio system without breaking the bank, the Fosi Audio ZH3 deserves serious consideration. It offers a level of performance and functionality that typically comes with a much higher price tag, making it a pragmatic choice for discerning listeners who want excellent sound quality and versatility without unnecessary expense.