Up to 84% in savings when you subscribe to The Absolute Sound
Logo Close Icon

Begin typing your search above and press return to search. Press Esc to cancel.

NuPrime DAC-9 DAC, STA-9 Stereo Amp, and HPA-9 Phono Preamp and Headphone Amp

NuPrime DAC-9 DAC, STA-9 Stereo Amp, and HPA-9 Phono Preamp and Headphone Amp

Founded by former NuForce CEO Jason Lim, NuPrime sells several higher-end NuForce products, plus it has developed additional NuPrime-branded gear. What distinguishes NuPrime components from those of most competitors are their prices, which range from moderate to (are you sitting down?) outright bargains. The equipment under review is potentially in the latter category. So just how low are the prices of the 9-series NuPrimes? The DAC-9 is priced at $749, the STA-9 at $649, and the HPA-9 at $649. But wait! While these prices make the 9-series components inexpensive (I started to say dirt cheap, but there’s nothing dirty about them), they are bargains only if they sound good. Let’s find out if that’s the case.

Let’s start with a quick overview of the 9-series NuPrime components: The DAC-9 is quite versatile, playing PCM files up to a 384kHz sampling rate and DSD files up to DSD256—which should make it capable of playing virtually any commercially available recordings (except MQA-encoded ones). A built-in volume control lets it drive power amplifiers directly. The STA-9 power amplifier produces 120 watts per channel and can be bridged for 290 watts (all ratings into both 8- and 4-ohm loads). The HPA-9 phone preamp/headphone amp has output jacks for three headphones (two 6.3mm and one 3.5mm) ranging from 16 to 1000 ohms. With its two line-level outputs, two line-level inputs, and mm/mc phono input, it can be used as a system controller. All three components are identically sized with dimensions of 9.25″ x 2.17″ x 11.06″ and are available in black or silver chassis with similar front-panel styling. They all come with one-year warranties for parts and labor—reasonable for components at these prices.

Now let’s look at each in more detail.

The DAC-9 DAC can also serve as a system controller, as it has several digital inputs, an analog line-level input, balanced and unbalanced outputs on XLR and RCA jacks, respectively, and most importantly, a remote control. It uses a field-programmable gate array (FPGA) as the volume control, with a ladder-type switched-resistor setup that ensures that there’s only one resistor in the volume control circuit at any time. It provides 99 volume settings in 0.5dB increments—impressive at any price. The DAC chip is an AK4490 EQ. DSD decoding up to DSD256 is becoming pretty standard via asynchronous USB inputs, but the DAC-9 also provides DSD decoding on the SPDIF input, and can even output DSD via DSD over PCM (DoP) coding on the SPDIF output, so, if you wanted to, you could use it as a USB-to-SPDIF converter. Native DSD decoding is provided via ASIO 2.1 or DoP. As usual, a separate driver is needed for Windows computers, and these drivers are downloadable for Windows XP and Windows 7, 8, and 10. A downloadable user manual is available on the NuPrime website. Although described as a PDF-format file, it actually turned out to be a Microsoft Word document, for what that’s worth. No big deal.

NuPrime DAC-9 DAC, STA-9 Stereo Amp, and HPA-9 Phono Preamp and Headphone Amp

The HPA-9 phono preamplifier/headphone amplifier is billed as a system controller, but has no remote control or balanced output, so unless you need a headphone amp or a phono input, the DAC-9 might offer more flexibility as a controller. The Class A HPA-9 provides a maximum output of 450mW into a 32-ohm load, 100mW into 600 ohms, which should drive most headphones satisfactorily. The phono preamp has an input load of 47k ohms for mm and 100 ohms for mc, with sensitivity of 4.0mV on the mm input and 0.4mV on the mc input. The default setting is for mm, but an internal switch changes that to mc. Here’s a design feature I hadn’t seen for some time: The volume control also serves as the on/off switch; turning it all the way down turns off the unit.

If I tell you the STA-9 stereo amplifier produces 120 watts per channel and weighs just under 10.5 pounds, you’d probably guess it uses a Class D output section. NuPrime describes the circuit as Class A and Class D, meaning that the input circuitry is Class A, which is pretty common for most amplifiers regardless of their output circuit. NuPrime’s website says it “is designed with enhanced even-order harmonic circuitry that mimics the most attractive features of tube-amp sound without incurring tubes’ drawbacks and limitations.” I’m not sure how I feel about adding distortion to tailor the sound, so we’ll have to see how it sounds. Its 47k-ohm input impedance should work with virtually any preamplifier. The Class D output section uses a 550kHz switching frequency for accurate reproduction of the musical signal. With a linear power supply, the STA-9 has both balanced and unbalanced input jacks. About the STA-9 the NuPrime website says, “Instead of the conventional saw-tooth configuration (for audio signal modulation), NuPrime’s patented circuit design uses a naturally occurring analog-modulating signal that adds neither noise nor jitter. Rather than reverting to off-the-shelf solutions, NuPrime’s in-house advances have further unlocked the switching amp’s potential without the difficulties pure digital-switching amplifiers simply cannot avoid—in other words, the best of both worlds.”

Setting up and Using the HPA-9, DAC-9, and STA-9
Rather than evaluate each component separately, I set them up as a system, although I’ll comment on each one later. As anticipated, two of the 9-series components fit onto a single 19-inch-wide shelf on my equipment rack. Because the DAC-9 was the only component with a remote, I used it as the system controller. The HPA-9 was the first component in the chain, and I connected my analog sources (a turntable and an FM tuner) to it so I could use its selector switch to choose an analog source. I connected one of the analog outputs of the HPA-9 to the analog input of the DAC-9, and connected my SOtM sMS-1000SQ digital server via USB cable to the DAC-9’s USB input. (Since the SOtM server is Linux-based, there’s no need to install a driver.) The DAC-9’s selector switch allowed me to choose among several digital inputs and a single analog input, which was the output of the HPA-9. I configured the STA-9 amplifiers as monoblocks and connected the DAC-9’s left and right unbalanced outputs to each monoblock via an unbalanced cable. Each STA-9 drove a KEF LS50 speaker. Each NuPrime component came with its own power cord, which I used. (Although these appeared pretty undistinguished, at this price point it seems unlikely that a potential user would invest in an aftermarket power cord.) All power cords were plugged directly into my wall outlet. I also used the rather flimsy-looking USB cable that came with the DAC-9. If I were upgrading the stock cables, I’d start with the USB one, but for the review, I used the stock.

Given that I received two STA-9s, I first connected them in their monoblock configuration. Jason Lim had told me that “due to the bridging circuit’s design, [the monoblock] actually sounds livelier and more dynamic.” Of course, I had to check out that claim during the review.

The instruction manuals that came with the components each had a quick-start section; these were clear and unambiguous. It’s important to read each manual carefully and follow it to the letter. I tried to skip a couple of steps and later had to retrace my steps and consult the instructions. Hopefully you won’t make that mistake. Line drawings of the components illustrate the layout and control placement of each unit.

When you flip the power switch on the rear of the DAC-9, the unit is placed in standby mode. You must first press and hold down the left knob for three seconds to put it into play mode after which a display appears on the front panel telling you which input is selected and the volume level. Or you can just use the power on/off switch on the remote. The initial input is always the coaxial (SPDIF) input and the initial volume setting is 50, which may be a bit loud. When a file starts to play, the DAC-9’s display shows you the file type and sampling rate. After a couple of seconds, the display switches to the input selected and the volume setting. You then have to select the USB input if that’s what you’re using (which will be the case for virtually all computers).

 

The first time you plug in the power cords, you’ll find a sticker over each of the IEC inputs warning you to change the power setting on the bottom of each component. They all work at either 115 volts or 230 volts, and a sliding switch on the bottom sets the proper voltage. They all come set at 230 volts, so for U.S. power you’ll need to move the orange switch to the 115-volt position.

The HPA-9 has an internal adjustment for the phono connection that lets you use a moving-magnet or moving-coil cartridge. It comes set for moving-magnet carts, but I’ll explain in detail how to reach the adjustment for moving-coils, since it’s not addressed in the manual. First, you must remove the case. Unscrew the four Philips screws on each side of the case. Slide the case back to release the clamp that attaches the case to the front of the chassis near the faceplate. Lift off the case. Near the back of the chassis you’ll see a small sliding switch labeled mm/mc. If you want to use an mc cartridge, slide the switch to that position. Replace the case, attach the leads from your turntable to the phono inputs on the back of the HPA-9, attach the ground wire if there is one, and turn the selector switch on the front of the HPA-9 to the Phono position. You’re ready to listen to LPs! The mc is designed for a cartridge with a 0.4mV output and a 100-ohm load, which are very common values for mc carts.

The DAC-9 remote control is obviously a budget unit, but quite thoughtfully designed with plenty of flexibility. Since it has 99 discrete settings, the volume control has a very gradual effect; as a result changes seem rather slow. The remote does have buttons for each of the digital and analog inputs, so you can select those directly—no scrolling through all the inputs until you reach the one you want to hear, which some remotes require. That’s convenient. There’s also a mute, which comes in handy when the phone rings. You can also turn off the DAC-9’s display; if you do, a single LED remains lit to show you the unit is turned on.

The HPA-9 has three headphone jacks, one for earphones and two for full-sized headphones. I tried some Sony XBA-H1 earphones (in-ear monitors), along with NAD Viso HP50, HiFiMan HE400, and AKG K701 headphones. The least sensitive of these were the HiFiMan HP400s, but the HPA-9 drove them to levels far louder than I cared to listen to.


NuPrime DAC-9 DAC, STA-9 Stereo Amp, and HPA-9 Phono Preamp and Headphone Amp

I used Clarity Cables Organic speaker cables to connect the speakers to the STA-9s. In monoblock configuration, you use the two speaker terminals near the edge of the chassis, so the cables’ spade lugs were a snap to connect, but for stereo mode, I suspect banana plugs would be easier to use, since the speaker terminals are fairly close together—an unavoidable result of using such a small chassis. Purist Audio Dimensions Venustas unbalanced interconnects linked the DAC-9 to the STA-9s, while Clarity Cables Organic interconnects connected the output of the HPA-9 to the analog input of the DAC-9. Crystal Cable’s Piccolo and Crystal Connect cables, respectively, connected the tuner and turntable to the HPA-9 headphone amp’s inputs.

The STA-9s, set up as monoblocks, were the most powerful amplifiers I’ve used, but unlike amps with Class AB output sections, they got only moderately warm to the touch. They were extremely quiet, fortunately—as are most amplifiers today.

I gave the 9-series gear at least 200 hours of break-in. The KEF LS50 speakers have a smooth but extended high-frequency response, and if your system is edgy, they will let you know. But there was a problem; hooked up as described, the output of the DAC-9 drove the STA-9 amplifiers, so when I played a digital source through the DAC-9, I couldn’t play it through the HPA-9. So to break in the HPA-9, I plugged in some headphones (the HiFiMan HE400s), turned on my FM tuner as an analog source, and played it through the ’phones. It sounded a bit weird to have two sources playing in the room, but it was just for the break-in period.

The 9-series components consist of three separate functional designs, and trying to operate them as a single system revealed some glitches. The fact that the HPA-9 had all the analog inputs, including the phono section and a volume control, while the DAC-9 had the master volume control was a little weird. Several times, I found myself cranking up the volume on the DAC-9 only to find I really needed to crank up the volume on the HPA-9. I guess you’d eventually get used to it. It would have been nice if there had been a remote control for the HPA-9, or better still, if the DAC-9 remote had also operated the HPA-9. If you bought the HPA-9 to use as a headphone amp, you would probably find the controls just fine. I wondered if it would have made more sense to combine the DAC and headphone amp; that combination is quite common, and appeals to those who listen to computers through headphones a lot. Then the phono preamplifier could have stood alone as a separate product. Oh, well, those are personal views; if I were an audio designer, I’d be making a lot more money than a reviewer.

Given their prices, you would probably not expect the STA-9, HPA-9, and DAC-9 to be audio jewelry, and you’d be right. A few parts seemed a bit cheap, like the source selection and volume control knobs, but generally construction was solid and attractive for the price.

 

Sound
So did the STA-9s sound like tube amplifiers? I’m not sure exactly in what respect they were supposed to sound like tube amplifiers, but they sounded a bit bright. Most tube amplifiers don’t sound bright; in fact, some sound a bit rolled-off in the high frequencies. Harmonics were fully developed, and as advertised, dynamic swings, small and large, were fast but not overdone.

I’m making these comments with monoblock STA-9 amplifiers driving speakers, using a digital source. Most of my listening today uses digital files, either downloaded PCM and DSD (and a very few MQA) high-resolution downloads, or rips from my CD collection, usually to AIFF format. It’s not that I dislike LPs; I have several thousand in my collection—but my reviewing duties tend to focus on digital gear. Let’s start with a girl-and-guitar album: Eva Cassidy’s The Best of Eva Cassidy (ripped to AIFF from Blix Street Records CD), specifically the audiophile fave “Over the Rainbow.” The NuPrime gear reproduced Cassidy’s expressive voice with a ton of detail and just a smidgen of treble emphasis. When she wailed, the NuPrime system accurately tracked dynamics without any compression. Instrumental sound was a little zingy, with overtones slightly emphasized. Overall sound was nice and open.

Turning to instrumental music, I had to try my old favorite La Folia 1490-1701 (ripped to AIFF format from Alia Vox CD AFA 9805), a collection of musical works composed over the indicated period based on the tune “La Folia,” performed by Jordi Savall and his band of Renaissance specialists. The track “Rodrigo Martinez, villancico” was reproduced with lots of detail and a strong, slightly emphasized high-frequency content. It wasn’t peaky or etched, just more prominent than I hear with most components. That HF emphasis highlighted the very busy percussion instruments, making it possible to follow them throughout the piece. Sometimes, the percussion recedes into a background haze, but here it stood out from the mix. Although the KEF speakers can’t really produce the deep bass present on this recording, I was impressed at how much bass the STA-9 amplifiers forced out of those transducers. Sometimes, much larger speakers don’t produce this much impact. Of course, I don’t usually drive the KEFs with 290 watts of power. This was a pleasant though brighter than usual rendition of this piece.

Switching to some choral music, I cued up The Tallis Scholars’ well-known performance of Allegri’s Miserere & Palestrina’s Missa Papae Marcelli (96kHz/24-bit FLAC, Gimell). The title track “Miserere” sounded a bit hard, again due to brightness. This recording was the worst-sounding of the lot, with a definitely emphasized treble, so that soprano voices speared out of the mix like lasers. It was actually slightly unpleasant to listen to. Normally, the HF content of this piece is smooth and well-balanced. Recorded in a church setting, the recording features an a capella choral group at the front of the soundstage, with a smaller solo group some distance behind the main group. There was indeed a pronounced sense of separation between those groups.


NuPrime DAC-9 DAC, STA-9 Stereo Amp, and HPA-9 Phono Preamp and Headphone Amp

With some misgivings, I switched to my turntable—I was eager to hear some newly acquired LPs. Unfortunately, when I adjusted the HPA-9 and DAC-9 to provide enough gain for my mc cartridge, I heard a slight bit of noise. The gain for the phono preamplifier was set by a combination of the volume controls of the HPA-9 and the DAC-9. Hint: Try to get most of the gain from the DAC-9 rather than the HPA-9. I tried several settings and reduced the noise to a barely perceptible level, but never got it to go away completely. It was masked by the music and surface noise, fortunately, so LPs were pleasant to listen to.

The first record I played was the Emerson Quartet augmented by Mstislav Rostropovich on cello playing Schubert’s String Quintet in C major on a 180-gram reissue of the Deutsche Grammophon stereo recording. The HAP-9/DAC-9 combination threw a solid soundstage with plenty of air around the instruments. Dynamics, small and large, were powerful and quick. Instrumental harmonics were dense and complete—this sounded like a real string quartet with an extra cello. Next up was Eva Cassidy’s The Best of Eva Cassidy dual 180-gram LP [Blix Street Records]. Her voice was portrayed with all its power and dynamic projection, but with no overload or shatter. There was no brittleness nor etch as there sometimes is with an inferior digital system. Both records, recent acquisitions, had amazingly quiet surfaces. (My turntable system sounded even better than I remembered; I plan on spending more time with it in the future.)

Overall, the high frequencies, which with the digital source selections had been a little bright, depending on the program material, were here smoother and more extended, but still a tad brighter than I’d like.

I’m a little surprised by how the NuPrime gear sounded with my reference albums, because just listening to the gear driving the KEFs on other material I had not gotten an impression that the NuPrime equipment so emphasized the HF range. I had thought it was detailed but fairly pleasant. But I’ve listened to my reference albums hundreds of times on a wide variety of equipment, and am well aware that they don’t normally sound bright.

I disconnected one of the STA-9s so I could listen to the STA-9 in stereo mode. I used the digital server only for this exercise. The single STA-9 didn’t have any difficulty driving the KEF speakers to loud levels. Tonal character sounded a smidgen lighter. “Over the Rainbow” was still a bit bright but not peaky. Guitar harmonics were still slightly zingy. Cassidy’s voice still had plenty of dynamic punch when she wailed. “Rodrigo Martinez, villancico” also had boosted high-frequency content. With the single amplifier, bass impact was less impressive than with the monoblock setup, though the low end was still pretty powerful. The soundfield was spacious and had a wide spread between the speakers. On “Miserere,” the sound was again brighter than usual, and again, the sense of depth between the main group and the solo group was quite pronounced, more so than I normally hear.

To listen with headphones, I disconnected the interconnects from the DAC to the amplifier and plugged them into an analog input on the HPA-9 so I could listen to the DAC-9 played through headphones. Basically, the headphone amplifier in the HPA-9 replaced the STA-9 amp. For purposes of comparison, I used the same server as the source for this part of the evaluation. The HPA-9 produced excellent sound from the different headphones I tried. From the HiFiMan HE400, I heard rather deep bass, with a fairly spacious though not precisely defined soundstage. High-frequency response was not very extended, which is consistent with what I hear from other headphone amplifiers. The Sony XBA-H1 earphones sounded deficient in bass, but that’s the way almost all earphones sound to me—it has to be something about my ears, because I hear plenty of low end from most normal headphones. The NAD Viso HP50 headphones had probably the best overall sound, with decent bass, and open, extended high frequencies. Speaking of high frequencies, the HPA-9’s were a welcome change from the STA-9’s. While extended, the highs were not at all overdone, so the objections I had to the NuPrime system’s sound through the power amplifiers were essentially eliminated through the headphone amplifier. That suggests it was the power amplifiers that were imposing the objectionable treble emphasis, i.e., the brightness. “Over the Rainbow” sounded pretty smooth in the high frequencies, with just a little sibilance from Cassidy’s voice. Her guitar’s timbre seemed to consist of far more body tone and less string tone. “Rodrigo Martinez, villancico” had deeper bass through both headphones, as expected, but with less impact than through the STA-9 amplifiers. “Miserere” was a breath of fresh air, with none of the almost painful brightness I heard through the STA-9. So again it would seem the power amplifier was behind the brightness problem, and the other components—the HPA-9 headphone amplifier and the DAC-9 DAC—were not to blame.

 

Comparison
I considered comparing the NuPrime gear to my reference system, which consists of an Audio Research VS115 amplifier (115Wpc, $6495), Audio Research SP20 ($9000), connected by a Clarity Cables balanced interconnect ($1400/meter), a PS Audio Directstream DAC ($5995) connected by an Audience Au24 SE USB cable ($980)—and that doesn’t even include power cords, which average around $1000 per component. But it struck me as pretty goofy to compare a $23,870 system to the $2696 NuPrime system. It seemed a lot more useful to compare the NuPrime gear to the $899 Yamaha A-S801 integrated amplifier I recently reviewed, but it had been returned to the importer. So I’ll draw from that review of the Yamaha I wrote (Issue 263).

The Yamaha A-S801 integrated amplifier had a similarly advanced DAC, although it only played DSD files up to DSD128—not a big drawback. It had an internal mm phono section for which I took some (justified) flack for not reviewing, an amazing assortment of controls for tone, loudness, and balance, all of which were operable from the remote control. The A-S801 was rated at 100Wpc and came in a full-sized chassis with typical Yamaha styling. And there was a headphone output, which sounded quite good. So although there’s less output power, the A-S801 provided lots of flexibility in a single, very reasonably priced chassis. And 100 watts per channel isn’t chopped liver—it drove the KEF speakers quite loudly, although I don’t enjoy extreme volumes (I need my ears). Because it was conceived as a single unit, the controls on the Yamaha were easier to use and far more flexible than the rudimentary ones on the HPA-9 and DAC-9; whether that matters to you is a personal decision.

So let’s address the most contentious area: the treble. The Yamaha showed not a smidgen of the HF emphasis of the NuPrime STA-9. Although it wasn’t as suave as some gear I’ve heard, including NuPrime’s excellent IDA-16 integrated amplifier/DAC (reviewed in Issue 252), it was always pleasantly listenable. About “Folia Rodrigo, villancico” I wrote, “the cascabels which open the piece were very clearly delineated, though without as much detail as I’ve heard on the best systems. The bass, which descends into the mid-20Hz range, was, of course, not fully developed on the small KEF speakers (with subwoofer off), but had plenty of impact, and the upper bass was quite detailed…Percussion instruments sounded harmonically accurate, but blurred into the background a bit more than they do with top-of-the-line systems…The A-S801 had plenty of microdynamic verve, so the music sounded quite lively.”

I went into more detail about the Yamaha’s sonic characteristics because listening was a pleasure, not marred by brightness. About “Miserere” I wrote, “The main group was reproduced with plenty of detail and clarity, without any trace of the distortion that some components impose on the piece. I’ve heard the main (front) choir distributed more widely across the soundstage, but singers within the group were well localized. The distant solo group was reproduced in a wash of reverberation, but the singers there were still understandable. I’ve heard this piece reproduced better, but by systems costing multiples of what the review system costs.” Again, there was absolutely no brightness in the sonic character. So if the much cheaper Yamaha’s 100 watts per channel is adequate for your needs, it offers better sound, more flexible controls, a DAC that’s only very slightly less flexible than the NuPrime’s, and a phono section that only supports mm cartridges. But it costs $899 as opposed to $2047 for the NuPrime gear system with a single 120Wpc STA-9 amplifier. And in my view, the Yamaha integrated amplifier was much more attractive, with nicer build-quality.

Bottom Line
Let’s do the math: As a system, the NuPrime 9-series components are quite reasonably priced—$2047 with a single 120Wpc STA-9 amplifier, or $2696 for the HPA-9, DAC-9, and two STA-9s in monoblock configuration. If you don’t want the headphone amp/phono preamp, a system with the DAC-9 and a single STA-9 could be had for $1398. And if you’re not into digital, a basic system with the HPA-9 headphone amp/phono preamp and a single STA-9 would cost $1298. This modular approach makes it possible to choose just the features you need/want at prices that in today’s audio market are fairly low. But to be a bargain, the NuPrime components must also sound good, and I’m sad to say, the sonic problems I heard prevent me from fully recommending them. The STA-9 power amplifiers sounded rather bright to me, making several pieces unpleasant to listen to, so they are only recommendable if you have speakers with rolled-off high frequencies. I wished I could have heard them without the added distortion component. The headphone amplifier in the HPA-9 sounded quite good, but the phono preamplifier was a bit noisy. I found it rather nice to listen to, but some might not. The DAC-9 seemed to have no significant flaws, so at its price, it’s easy to fully recommend.

Specs & Pricing

DAC-9 DAC
Type: Full-featured DAC/preamp
Inputs: 1 x USB PCM/DSD digital (PCM up to 384kHz & DSD up to DSD256); 1 x coaxial digital SPDIF (PCM up to 384kHz); 1 x optical digital SPDIF (PCM up to 192KHz); 1 x Bluetooth or WiFi receiver module (optional); 1 x AES balanced XLR; 1 x analog stereo RCA (does not go through A/D conversion, analog input is selected by the preamp directly to analog outputs)
Formats supported: FLAC, AIFF, PCM up to 384kHz, DSD up to DSD256
Output: 1 x pair of stereo RCA out (max output 4V); 1 x pair of stereo XLR balanced out (max output 8V); 1 x optical SPDIF out
Dimensions: 9.25″ x  2.17″ x 11.06″ including feet
Weight: 5.1 lbs.
Price: $749

STA-9 Stereo Amplifier
Type: Solid-state, Class D output stage
Output power: 120Wpc into 8 and 4 ohms
Inputs: 1 x RCA unbalanced input; 1 x XLR balanced input
Input impedance: 47k ohms
Dimensions:  9.25″ x  2.17″ x 11.06″ including feet
Weight: 10.5 lbs.
Price: $649

HPA-9 Headphone amplifier/phono preamplifier/preamplifier
Type: Solid-state, Class A
Inputs: 1 x phono (mc, mm); 2 x analog stereo RCA
Outputs: 1 x 3.5mm earphone; 2 x 6.3mm headphones; 2 x pair of stereo RCA 
Max. output power: 450mW into 32 ohms; 100mW into 600 ohms
Output impedance: 16–1000 ohms
Phono input loading: 47k ohms for mm; 100 ohms for mc
Dimensions: 9.25″ x  2.17″ x 11.06″ including feet
Weight: 5.5 lbs.
Price: $649

NUPRIME AUDIO
Taiwan Service Center
No.33 Chiu Kan Kou Road
Ray Fong Town, Taipei 224
Taiwan

NuPrime Support Center
709 Plaza Drive, Suite 2-179
Chesterton, IN 46304
(219) 370-6549
nuprimeaudio.com

Brand Uprise (U.S. Distributor)
Anna Zhao
205 Autrey Street
Milpitas, CA 95035
(408) 807-0216
branduprise.com

Manufacturer Comment

NuPrime Series 9

We have confirmed in our lab that the KEF LS50 does not work well with the warmer NuPrime Class A+D STA-9. The high frequency extension for which the LS50 is best known emphasizes the even-order harmonics of the STA-9 that ended up sounding harsh. We further note that the reviewer has previously reviewed the NuPrime IDA-16 with the LS50 with very satisfactory results. The IDA-16 was based on a NuPrime pure Class-D design and was able to bring out the best in the LS50.

Jason Lim, NuPrime

Vade Forrester

By Vade Forrester

More articles from this editor

Read Next From Review

See all

Adblocker Detected

"Neque porro quisquam est qui dolorem ipsum quia dolor sit amet, consectetur, adipisci velit..."

"There is no one who loves pain itself, who seeks after it and wants to have it, simply because it is pain..."