NuPrime IA-9X Integrated Amplifier Review – HiFiReport
NuPrime’s acclaimed mid-9th grade series has undergone a complete makeover this past year, evolving into the 9X series. Among the new line-up is a model not previously seen in the NuPrime product range: the IA-9X integrated amplifier.
You may find it curious that an integrated amplifier is considered unusual. Does NuPrime ever offer integrated amplifiers? Indeed they did. However, previous NuPrime integrated amplifiers have prioritized ease of use and flexibility, often including DAC or wireless streaming capabilities. Analog integrated amplifiers were rare. The IA-9X, in contrast, focuses entirely on the analog domain, carefully removing interference from the digital circuit. It combines NuPrime’s exclusive ODC (Only Distortion Cancellation) technology and harmonic generation circuitry to improve sound quality and enrich the listening experience. In addition, it includes an MM phono stage, providing discerning audiophiles with an excellent new option.
ODC Technology Drops From Flagship Components
The IA-9X maintains the classic beauty and size of the original 9 series, maintaining a width of just 23.5 cm, half the size of standard audio components. Despite its compact form, it retains NuPrime’s famous Class-D amplification technology. It delivers a continuous output of 90 watts into 8 ohms and 145 watts into 4 ohms, which is enough power for most small to mid-range speakers.
A defining feature of the IA-9X is the inclusion of NuPrime’s proprietary ODC technology.
Originally designed for the flagship Evolution STA stereo power amplifier, ODC technology now extends to the 9X series.
ODC, short for “Only Distortion Cancellation,” directly targets distortion to eliminate it, leaving the original signal untouched. It outputs signals to MOSFET components and output filter circuits to correct errors, greatly reducing total harmonic distortion.
NuPrime modified the ODC circuit, which includes a MUSES 8820 amplifier and uses the Delta Sigma circuit architecture.
The IA-9X includes two ODC modules, achieving harmonic distortion as low as 0.0014% (at 5W).
However, low harmonic distortion alone does not guarantee a pleasant sound. The physical pleasantness of the sound is closely related to the composition of the harmonic content. To deal with this, the IA-9X uses the Harmonic Generation function.
This technology has previously been used in NuPrime’s top models, including the EVO and AMG series, and has now been integrated into the 9X series.
Harmonic generation technology subtly enhances certain harmonic components within the signal, providing a warm, tube-like sonic character and long-lasting resonance, resulting in a more engaging and pleasant sound.
Given that harmonic generation is a form of sonic tuning, the IA-9X allows for manual activation and deactivation. A toggle switch on the front panel provides two settings. In the low “fo” mode, the IA-9X works only in ODC mode, prioritizing the lowest distortion. Switching to the upper “2fo” position combines both ODC mode and harmonic generation, introducing desirable harmonics into the amplifier’s sonic signature.
This design approach allows the IA-9X to provide both monitor-like precision and immersive music, giving users a wide variety of listening pleasure.
Integrated MM Phono stage
In terms of connectivity, the IA-9X is generously equipped. Features two sets of unbalanced RCA inputs, one set of balanced XLR inputs, and a dedicated RCA MM phono input for connecting turntables.
In addition, the IA-9X MM phono stage allows adjustable input contacts and the ability to enhance compatibility with various MM cartridges. Adjustment switches are located on the bottom panel, offering impedance settings of 32k, 47k, and 100k ohms, and power settings of 320pf, 100pf, and 220pf, accepting a wide variety of MM cartridges.
Another notable feature is the IA-9X’s volume control, which provides 99 precise steps for precise volume adjustment to achieve the ideal listening level.
Small pins on the front panel light up to indicate the selected input and volume level.
Adding further ease of use, the IA-9X includes a remote control to manage various functions, including power on/off, volume, mute, input selection (up/down), and direct input access.
Two Sonic Profiles in One Amplifier
The listening test was performed in the HiFiReport listening room, which has the following components: an Intel NUC i3 mini-PC acting as a Roon Core, a Telos EMP music server as a transmitter, connected via USB to a North Star Design USB DAC32. The DAC was connected to the IA-9X via balanced XLR cables, driving Audio Physic bookshelf speakers Step 35. A Linear Acoustic LAV-60 MKII integrated amplifier served as a reference.
I first tested the harmonic generation function of the IA-9X using stringed music to see if there was any difference. The piece chosen was Bruch’s Scottish Fantasy by David Oistrakh.
Switching between harmonic generation settings reveals that even without harmonic enhancement, the IA-9X has a pleasant warmth.
Engaging harmonic generation resulted in a full, rich sound with rising resonance from the violin, adding a shimmering and slightly dense quality. Instrument images seemed to grow slightly louder, and the overall volume seemed to sound more subtle. Rejecting it revealed cleaner textures, more distinct violin lines, sharper dynamic shifts, and a simpler musical presentation.
Of course, speakers also play a role. Audio Physic Step 35 speakers naturally have a nice body and warmth, and adding harmonic generation furthered this richness, slightly reducing the power of the violin.
Switching to the PMC Prodige 1 speakers, which are monitor-like with a flat frequency response and tight texture, the harmonic generation feature proved beneficial. It has improved the midrange, added fullness to the string instruments, and created a smooth, harmonious, and enjoyable listening experience.
The difference between engaging and extracting harmonic generation on the IA-9X is huge. It effectively offers two sonic profiles within a single amplifier, improving its flexibility in system matching.
Returning to the speakers of step 35 and removing the harmonic generation, I continued to listen to Bruch’s Scottish Fantasy. The strong, gentle accompaniment of the lower string at the beginning, supporting the moving violin solo above, showed a remarkably stable low-frequency base and clear sonic structures. The feel of the weight was good, showing the excellent control of the IA-9X.
As other string parts gradually joined in, the musical scale grew, and the dynamic changes increased. The IA-9X perfectly provided the overall layering of the strings, the separation between sections, the contrast between soloists, and the soloist’s focus and presence. It all worked admirably, prompting an internal nod of approval: “Well done!”
Wide soundstage
Next, I played “Ten New Songs” by Canadian folk singer Leonard Cohen. This album has very slow tempos and is characterized by the presence of clear frequencies in the programs, with a large bass and drum content, which leads to a large proportion of low frequencies throughout the spectrum. This performs the desired low frequency control test of the system.
With the IA-9X, the low frequencies showed not only adequate value but also high-quality performance in terms of definition, pitch, shape, extension, and layering.
While the IA-9X’s low-frequency performance was outstanding, its high-frequency response remained sweet, comfortable, and accurate.
In addition, this album revealed the IA-9X’s excellent balance, especially at low volumes. The midrange has retained enough body, and the low frequencies remain clear, with distinct definition and layering. The sound was not thin or weak, indicating that the IA-9X performs well even at low listening levels.
Similarly, Jacky Cheung’s Cantonese album “Private Corner,” featuring primarily jazz-style tracks with audiophile-grade recordings and high production quality, highlighted Cheung’s expressive, emotionally rich, and captivating vocal artistry with the IA-9X.
His voice displayed clear dynamic range, precise imaging, and well-defined contours, which enhanced the contrast and three-dimensionality of the voice, easily capturing the listener’s attention.
Switching to the more easily driven PMC Prodigy 1 speakers allowed Cheung’s vocals to run wilder, expressing wilder emotions and creating a more immersive listening experience.
Engaging the harmonic generation function at this point added warmth and smoothness to the vocals. During loud passages, the high frequencies become sharp and harsh, resulting in a comfortable and comfortable listening without sacrificing important nuances.
Wide Variation of Music
The IA-9X exhibits impressive versatility across a wide variety of music genres, performing well with pop, jazz, and rock.
For an amplifier of its compact size, the IA-9X shows remarkable openness, with excellent high and low extension, which sounds effortless and natural. It handles loud and quiet passages with aplomb, providing ample detail and body even at low volumes.
In addition, its control capabilities are a significant force, capable of driving large speakers and handling large pieces of music such as film scores and symphonies. Equally suitable for home theater systems, it shows its versatility.
Such a small amplifier that delivers such great satisfaction – only NuPrime can achieve this.
Details
* Type: Integrated Amplifier
* Output Power: 90 watts / 8Ω, 145 watts / 4Ω
* Frequency Response: 10 Hz ~ 50 kHz (-3dB)
* Total Harmonic Distortion / Noise Reduction Ratio: 0.0014% / 95dB @ 5W, 0.003% / 105dB @ 50W
* Gain: 17x
* Inputs: XLR × 1, RCA × 2, Phono × 1
* Dimensions: 235 × 60 × 281 mm (Width × Height × Depth)
* Weight: 3.8 kg
