iBasso AMP16 Review

 

Introduction:

iBasso, a renowned Chinese company specializing in portable audio products, has a strong reputation for crafting high-quality Digital Audio Players (DAPs), amplifiers, in-ear monitors, and headphones. Among their offerings are amplifier modules tailored for their DAPs, and the AMP16 is a standout addition designed specifically for the iBasso DX340. As a hybrid tube/solid-state amplifier module, the AMP16 promises to elevate the DX340’s audio performance, offering a unique blend of analog warmth and solid-state precision.

This review explores its design, sound quality, and overall performance.

 

Disclaimer:

I would like to thank iBasso for providing the AMP16 Card as a review sample. I am not affiliated with iBasso beyond this review, and the opinions expressed here are my true and unaltered impressions of the product.

 

Price & Availability:

The iBasso AMP16 is priced at $219.00 USD. For the most accurate pricing and availability, please visit the official iBasso website or authorized retailers.

• iBasso AMP16 Amplifier Module

  

Package and Accessories:

The AMP16 arrives in a compact metal box that features foam layers. Inside the box are the following items.

• 1 x iBasso AMP16 Amplifier Module
• 1 x Screwdriver
• 6 x Screws
• 1 x Warranty Card

The amplifier module is securely packed in an antistatic bag (Electrostatic Discharge bag), which is recommended for storage to protect the module when not in use. The included screwdriver and hex screws facilitate easy installation onto the DX340 DAP.

 

 

Design & Features:

The iBasso AMP16 amplifier card, designed for the DX340 DAP, integrates both vacuum tube and solid-state amplification within a compact form factor. Its external construction features a brushed aluminum front plate, offering durability and a premium aesthetic. The front panel includes a 4.4mm balanced output for increased power delivery and channel separation, a 3.5mm single-ended output for broader headphone compatibility, and a DC-IN 12V port for optional external power.

Internally, the AMP16 employs a carefully engineered audio pathway. This includes two Raytheon JAN6418 vacuum tubes, which contribute to the module’s unique sonic characteristics.

Complementing the tubes are four Texas Instruments high-performance dual OPAMPs and four BUF634A buffer amplifiers. The selection of specific capacitors within the circuit aims to optimize audio signal integrity and performance.

The module offers two distinct output modes: Tube Mode and Class AB Mode. Tube Mode engages the vacuum tubes in the amplification process, imparting a warmer and potentially more harmonically rich sound. Class AB Mode relies solely on the solid-state components, striving for a cleaner and more linear output with enhanced detail retrieval. Users can switch between these modes to tailor the sound signature to their preferences and connected headphones.

A 100-step JRC volume control is utilized for precise volume adjustments. This component is also designed to minimize potential background noise that can be associated with vacuum tube operation, aiming for a cleaner overall audio presentation.

To ensure consistent performance between individual units, each pair of JAN6418 tubes undergoes rigorous testing and SINAD (Signal-to-Noise and Distortion ratio) matching using APX555 audio analysis equipment before being implemented in production. This meticulous pairing process aims to minimize sonic variations and maintain a high standard of audio quality. Due to the time-intensive nature of this testing, the number of matched tube pairs produced daily is limited.

The physical mounting of the vacuum tubes within the AMP16 chassis utilizes a “hanging” installation method with PORON material. This suspension system is engineered to provide effective shock absorption, thereby significantly reducing microphonic effects, unwanted noise resulting from vibrations affecting the sensitive tube elements. A perforated metal top cover serves to dissipate heat generated during operation and provides a visual indication of the tubes’ presence.

The iBasso AMP16 amplifier card is designed for a straightforward installation process with the DX340 DAP. The inclusion of a dedicated screwdriver and two screws simplifies the physical connection, allowing users to easily and securely attach the module to their device. This user-friendly design minimizes complexity and ensures a stable connection.

 

Technical Specifications: 

4.4mm Balanced (TRRRS) Headphone Output (Class AB Mode):

• Frequency Response: 10Hz–40kHz (±0.5dB)
• SNR: 122dB
• THD+N: -117dB (A-weighted, 300Ω load)
• Dynamic Range: 122dB
• Crosstalk: -120dB
• Max. Output Level: 8.3Vrms (Super Gain), 6.0Vrms (High Gain)
• Output Power: 2000mW + 2000mW @ 32Ω (12V DC-IN), 1000mW + 1000mW @ 32Ω (Battery)
• Output Impedance: Not specified (typically low for balanced outputs)

3.5mm Single-Ended (TRS) Headphone Output (Class AB Mode): 

• Frequency Response: 10Hz–40kHz (±0.5dB)
• SNR: 120dB
• THD+N: -108dB (A-weighted, 300Ω load)
• Dynamic Range: 120dB
• Crosstalk: -117dB
• Max. Output Level: 4.1Vrms (Super Gain), 3.0Vrms (High Gain)
• Output Power: 500mW + 500mW @ 32Ω (12V DC-IN), 260mW + 260mW @ 32Ω (Battery)
• Output Impedance: Not specified (typically low for single-ended outputs)

4.4mm Balanced (Tube Mode): 

• Frequency Response: 20Hz–40kHz (±1dB)
• Max. Output Level: 7.5Vrms (Super Gain), 4.6Vrms (High Gain)
• Output Power: 1500mW + 1500mW @ 32Ω (12V DC-IN), 660mW + 660mW @ 32Ω (Battery)

3.5mm Single-Ended (Tube Mode): 

• Frequency Response: 20Hz–40kHz (±1dB)
• Max. Output Level: 3.75Vrms (Super Gain), 2.3Vrms (High Gain)
• Output Power: 400mW + 400mW @ 32Ω (12V DC-IN), 150mW + 150mW @ 32Ω (Battery)

 

Amplification & Background Noise:

The iBasso DX340, when used with the AMP16 amplifier module, demonstrates a highly adaptable audio output through its dual Tube and Class AB modes, allowing for user-selectable sound characteristics. The AMP16 provides significant power output, enabling effective operation with a diverse range of headphones, particularly via its 4.4mm balanced output.

In Class AB Mode using the 4.4mm balanced output, the AMP16 achieves a power output of 2000mW + 2000mW into a 32Ω load with a 12V DC-IN, and 1000mW + 1000mW into 32Ω on battery power. Tube Mode delivers 1500mW + 1500mW into 32Ω (12V DC-IN) and 660mW + 660mW into 32Ω on battery. The 3.5mm single-ended output in Class AB Mode provides 500mW + 500mW into 32Ω (12V DC-IN) and 260mW + 260mW into 32Ω on battery, while Tube Mode yields 400mW + 400mW into 32Ω (12V DC-IN) and 150mW + 150mW into 32Ω on battery. This power output capacity supports compatibility with both high-sensitivity and low-sensitivity headphone designs.

The AMP16 generally provides a quiet background in both modes, contributing to a clear listening experience. However, due to the inherent sensitivity of vacuum tubes, Tube Mode can exhibit minor microphonic effects noticeable during quiet passages. For instance, tapping the device during a pause may produce a faint ringing, a typical characteristic of tube amplification. I’ve also noticed occasional interference in this mode that seemed to originate from nearby mobile devices, although it rarely intruded on the actual music listening.

iBasso has incorporated features such as PORON suspension for the tubes and a 100-step JRC volume control aimed at reducing these occurrences.

In contrast, Class AB Mode eliminates microphonic effects, interference, and background noise entirely, delivering a clean and detailed sound profile.

 

Equipment’s used for this review:

• DAP’s             : iBasso DX360
• AMP Card’s   : AMP16, AMP15
• IEM’s              : iBasso IT07, Oriveti OH700VB, Campfire Audio Astrolith
• Headphones  : iBasso SR3, SIVGA P2 Pro

 

Albums & tracks used for this review:

• Norah Jones – Come Away With Me (Apple Music Lossless)
• Adele – My Little Love (Apple Music Lossless)
• Sarah McLachlan – Angel (Flac 24bit/48kHz)
• Sertap Erener – Aşk (Flac 16bit/44.1kHz)
• Edith Piaf – Non Je Ne Regrette Rien (Flac 16bit/44.1kHz)
• Diana Krall – So Wonderful (DSF)
• Aretha Franklin – I Say A Little Payer (Flac 24bit/96kHz)
• Michael Jackson – Billie Jean (Flac 24bit/96kHz)
• George Michael – Don’t Let the Sun Go Down on Me (Flac 24bit/192kHz)
• David Bowie – Heroes (Flac 24bit/192kHz)
• Elton John – Rocket Man ((Flac 24bit/96kHz)
• Barry White – Just The Way You Are (Flac 24bit/48kHz)
• Isaac Hayes – Walk On By (Flac 16bit/44.1kHz)
• Sting – Englishman in New York – (Flac 24bit/48kHz)
• Eric Clapton – Wonderful Tonight (Flac 24bit/96kHz)
• Dave Gahan – Kingdom (Tidal Hi-Fi)
• Radiohead – Live in Berlin “Album” (Apple Music Lossless)
• Radiohead – Pyramid Song (Apple Music Lossless)
• U2 – Sunday Bloody Sunday (Flac 16bit/44.1kHz)
• Muse – Hysteria (Flac 24bit/96kHz)
• Red Hot Chili Peppers – Nobody Weird Like Me (Flac 24bit/48kHz)
• Michael Jackson – Billie Jean (Flac 24bit/96kHz)
• Bear McCreary’s – Valkyries (Deezer HiFi)
• Bro Safari, UFO! – Drama (Deezer HiFi)
• Armin Van Buuren – Vini Vici (Flac 16bit/44.1kHz)
• Daft Punk – Instant Crush (Flac 24bit/96kHz)
• Daft Punk – Doin’ it Right (Flac 24bit/96kHz)
• Lorde – Royals (Flac 24bit/48kHz)
• Massive Attack – Angel (Flac 24bit/48kHz)
• Toutant – Rebirth (Deezer HiFi)
• Gogo Penguin – Raven (Flac 24bit/192kHz)
• Gogo Penguin – Murmuration (Flac 24bit/192kHz)
• Portishead – It Could Be Sweet (Apple Music Lossless)
• Hans Zimmer – The Dark Knight OST (Flac 24bit/96kHz)
• Max Richter – On the Nature of Daylight (Flac 24bit/96kHz)
• Charly Antolini – Duwadjuwandadu (Flac 24bit/192kHz)
• Tchaikovsky – Symphony No. 5 (Flac 16bit/44.1kHz)
• Ferit Odman – Look, Stop & Listen (Flac 24bit/192kHz)
• Chopin – Nocturn No. 20 In C-Sharp Minor (Flac 16bit/44.1kHz)
• Clair de Lune – Claude Debussy (Spotify)
• Fazıl Say – Nazım Oratoryosu (Live) (Flac 16bit/44.1kHz)
• Vivaldi – Le QuarttroStagioni “The Four Season” (Apple Music Lossless)
• Pink Floyd – Shine On You Crazy Diamond (Apple Music Lossless)
• Miles Davis – So What (Deezer HiFi)
• Otto Liebert& Luna Negra – The River (Flac 24bit/192kHz)
• Lunatic Soul – The Passage (Flac 16bit/44.1kHz)
• Deftones – My Own Summer (Shove it) (Flac 16bit/44.1kHz)
• Metallica – Dyers Eve (Flac 24bit/96kHz)
• Metallica – Sad but True (Flac 24bit/96kHz)
• Opeth – Windowpane (Flac 16bit/44.1kHz)
• Megadeth – Sweating Bullets (Tidal Hi-Fi)
• Rush’s – Tom Sawyer (Flac 16bit/44.1kHz)
• Slayer – Angel of Death (Spotify)
• Liquid Tension Experiment 2 – Acid Rain (Spotify)
• Yosi Horikawa – Bubbles (Spotify)

 

The Sound:

The iBasso DX340 paired with the AMP16 amplifier module offers an exceptionally versatile listening experience, thanks to its dual Tube and Class AB modes, which allow users to customize the sound signature to their preferences. The AMP16 is a notably powerful card, capable of driving a wide variety of headphones with ease, particularly through its 4.4mm balanced output, which delivers significant headroom for dynamic and impactful playback across different genres. When compared to its predecessor, the AMP15, the AMP16 stands out as more dynamic and exciting, bringing a sense of energy and engagement to the sound. In contrast, the AMP15 leans toward a more resolving and clinical presentation, prioritizing precision over emotional warmth.

This review is based on my impressions after a burn-in period of approximately 150+ hours, using IEMs such as the iBasso IT07, Campfire Audio Astrolith, Oriveti OH700VB and headphones like the iBasso SR3 and SIVGA P2 Pro.

 

iBasso DX340 + AMP16 Combination (Lows / Mids / Highs / Soundstage):

Tube Mode:

In Tube Mode, the AMP16 delivers a bass response characterized by both significant quantity and a strong punch, lending a dynamic and exciting quality to the low frequencies. The subbass extends deeply with a warm, rounded tonality, enhancing the overall listening experience, particularly for bass-heavy music. This deep extension provides a visceral impact in electronic tracks, while the midbass offers a hard-hitting quality that adds groove and rhythm. This emphasis on impact results in a fuller, more emotive bass response, prioritizing engagement over the most intricate detailing and tightest control. While the bass is rich and involving, the finest nuances in texture and resolution might be slightly less pronounced.

The midrange in Tube Mode stands out with its warm, thick, and intimate presentation, adding substantial body to both vocals and instruments. This warmth creates a sense of closeness, akin to a performance in a small, intimate setting. Vocals acquire a lush, velvety texture that deepens their emotional impact. Instruments like acoustic guitars, pianos, and strings gain a rich, full-bodied tone, emphasizing their natural resonance. This mode excels with vocal-centric tracks and genres like jazz or acoustic music, where emotional connection is key. However, the inherent warmth can subtly veil the most delicate micro-details in the midrange.

The treble in Tube Mode is smooth and detailed, offering a gentle character that ensures comfortable listening even over extended periods. High-frequency elements such as cymbals and string harmonics are rendered naturally, without harshness or sibilance. This smoothness is well-suited for genres where high-frequency energy needs to be managed for comfortable listening. The trade-off is a slight reduction in sparkle and micro-detail, potentially making the upper frequencies feel less extended and open compared to a more neutral presentation.

The soundstage in Tube Mode presents a more intimate spatial experience, with instruments and vocals positioned closer together, creating a focused and engaging soundscape. This intimacy enhances the emotional impact of the music. Imaging remains precise, with individual elements clearly placed within the soundstage, preventing congestion. This mode is particularly effective for recordings where a sense of closeness and presence is desired, such as solo performances or small ensembles, though it may not offer the expansive spatial cues ideal for large orchestral works.

Overall, Tube Mode on the AMP16 provides a sweeter, warmer, and more dynamic sound, fully embodying the characteristics of vacuum tubes. The analog-like quality creates an exciting and emotionally engaging listening experience, ideal for those who prioritize musicality and warmth.

 

Class AB Mode:

Switching to Class AB Mode on the AMP16 results in a tightened bass response that retains its punchy character, offering a well-balanced combination of clarity and impact. The subbass remains deep but exhibits a cleaner decay compared to Tube Mode, leading to a more controlled and articulate low-end presentation. The midbass delivers a taut, rhythmic kick that complements energetic genres. This mode achieves a balance between power and precision, providing a refined low-end response with both impact and clarity.

The midrange in Class AB Mode is notably cleaner and more detailed than in Tube Mode, aiming for a pristine and transparent presentation that prioritizes accuracy. Vocals reveal heightened clarity, with subtle nuances in tone and delivery becoming prominent, making this mode excellent for critical listening. Instruments are rendered with greater separation and accuracy, allowing for easier discernment of individual layers within the midrange. This mode is well-suited for genres that benefit from a more analytical approach, such as jazz and classical music, where instrumental detail is crucial. While less warm than Tube Mode, the midrange retains a natural and musical quality.

The treble in Class AB Mode excels with exceptional clarity and energy, offering a more immediate and lively sound than Tube Mode. High-frequency elements shimmer with a crisp, airy quality, and string harmonics are detailed without harshness, adding a sense of space and immersion. This mode delivers more micro-detail and extension in the upper frequencies, making it ideal for genres that require precision, such as jazz, classical, or electronic music. The treble energy is well-controlled, avoiding sibilance or fatigue, and provides a more open and extended presentation.

The soundstage in Class AB Mode is significantly wider and deeper than in Tube Mode, creating a more expansive and three-dimensional listening experience. Spatial cues are more pronounced, with instruments and effects stretching across a broader canvas, and the increased depth allows for better layering of elements. This mode excels in reproducing the sense of a live performance, particularly for orchestral or large-scale recordings, where instrument separation and localization are excellent, resulting in a highly immersive and realistic spatial presentation.

Ultimately, Class AB Mode on the AMP16 prioritizes enhanced resolution and excellent dynamic range, delivering a clean and wonderfully detailed sound profile. The AMP16 provides a clean and dark background in both modes, ensuring that the music remains free from unwanted noise.

 

Comparison:

iBasso DX340 + AMP16 versus iBasso DX340 + AMP15:

In Tube Mode, the AMP16 delivers a punchier and warmer bass compared to the AMP15, with greater quantity that adds a dynamic and engaging flair to the low end, though it sacrifices some texture and resolution. In Class AB Mode, the AMP16 maintains this punch but enhances clarity, offering a tighter and more controlled bass response than the AMP15. The AMP15, with its more resolving and clinical nature, provides better bass texture and detail but lacks the dynamic excitement and warmth of the AMP16.

The AMP16’s midrange in Tube Mode is warmer and more intimate than the AMP15, with a thicker presentation that adds body to vocals and instruments, creating a lush and emotive sound that feels more engaging. In Class AB Mode, the AMP16 offers a cleaner and more detailed midrange, with improved vocal clarity and instrument separation that surpasses the AMP15’s more analytical approach, while still maintaining a natural and musical tone.

In Tube Mode, the AMP16’s treble is smoother and slightly recessed compared to the AMP15, lacking the sparkle and extension of the AMP15’s more clinical treble presentation. In Class AB Mode, the AMP16 surpasses the AMP15 with greater clarity, energy, and micro-detail, delivering a more immediate and lively treble response. The AMP15’s treble is more resolving but can feel less engaging and dynamic compared to the AMP16 in Class AB Mode.

The AMP16 in Class AB Mode offers a wider and deeper soundstage than the AMP15, with more expansive spatial cues and better layering of elements. In Tube Mode, the AMP16’s soundstage is slightly smaller than the AMP15 but retains strong imaging and a cohesive presence. The AMP15 provides a more clinical soundstage with good resolution but lacks the dynamic versatility and emotional engagement of the AMP16’s dual modes.

 

Conclusion:

The iBasso AMP16 amplifier module enhances the DX340 DAP, delivering a versatile, high-performance upgrade for audiophiles. It features dual Tube and Class AB modes, offering distinct sound profiles: Tube Mode provides warm, dynamic, and emotionally rich audio, while Class AB Mode ensures clean, detailed, and precise sound with excellent resolution. With up to 2000mW per channel via the 4.4mm balanced output, it drives sensitive IEMs, as well as demanding headphones, with excellent control and dynamics.

Equipped with special hardware components, including Raytheon JAN6418 vacuum tubes, Texas Instruments OPAMPs, and a 100-step JRC volume control, the AMP16 reflects iBasso’s dedication to quality. Tube Mode may introduce slight background noise with sensitive IEMs, but Class AB Mode eliminates this for a pristine experience. Compared to the already impressive AMP15 stock card, the AMP16 offers a more dynamic and engaging sound. Despite lacking a dedicated line-out, its power, versatility, and value at $219.00 USD make it an exceptional upgrade for the DX340, delivering a tailored, captivating listening experience for audiophiles.

 

Pros and Cons:

• + Versatile Tube and Class AB modes for tailored sound
• + Dynamic and engaging sound, surpassing the already solid sounding AMP15 stock card
• + Powerful output (up to 2000mW per channel) drives diverse headphones
• + Clean, noise-free performance in Class AB Mode
• + Great value at $219.00 USD

• – Slight background noise in Tube Mode with sensitive IEMs
• – No dedicated line-out option

 

Thank you for the Read!