PRICE $850
AT A GLANCE
Plus
Cheap
Fanless
RCA and balanced XLR inputs
Auto standby
12 volt and Sign energy set off
Minus
Wants six-inch clearance when rack mounted
THE VERDICT
A rock-solid, reasonably priced and enticing amp for powering seven channels in a surround-sound AV or house theater system. It delivers audiophile-quality sound for a couple of buck a watt.
Audio amplifiers have however one activity: take {an electrical} sign and make it extra highly effective with out altering its character. amplifier is as clear as doable, neither including nor subtracting something from what you hear. The OSD Nero XA7180 guarantees all that plus excessive effectivity at a really enticing worth.
Earlier than attending CEDIA 2022 in Dallas TX, I used to be not conversant in OSD, an organization specializing in high-performance, cost-effective gear—my most well-liked kind. A little bit of Googling revealed the corporate has a superb status in on-line boards, so I took the plunge on doing a full evaluation. This proved well timed, as 2023 introduced quite a few premium AVRs with preamp outputs appropriate with the XA7180.
On this aggressive enviornment of solid-state house theater amps, corporations like ATI, Monoprice, Emotiva, and Outlaw supply related energy per greenback. Nonetheless, OSD stands out for its mixture of worth and options, making it probably the most reasonably priced seven-channel amplifier Sound & Imaginative and prescient has examined. Regardless of the low value, it boasts a sturdy construct, together with each RCA and XLR inputs, and particular person standing LEDs for every channel on the entrance panel.
Options
The one settings on this amp it’s important to fear about are associated energy, with an on/off button on the entrance and a toggle swap within the again that permits you to select to make use of a voltage set off or enter sign to mechanically activate the unit.
The excellent options of the design is using a toroidal energy provide, which does make it heavy however supplies a stable basis for an amp that advertises 122 watts per channel RMS energy into 8 ohm hundreds, all seven channels pushed, and the inclusion of XLR balanced inputs.
Audio amplification usually supplies a 3 dB enhance in output when energy is doubled. You would possibly query if this amp’s rated energy is adequate in comparison with AVRs with related outputs. Notably, OSD gives complete and detailed energy scores, illustrating efficiency below numerous hundreds. These embody single-channel scores, all channels pushed scores, 4 ohms, 8 ohms, 0.1% THD, 1% THD, and extra.
Driving only one channel the amp can output 300 W RMS into 4 ohms with 1% THD. For 8 ohms, that determine is 180 watts. These numbers describe the headroom. However the spec of best curiosity is wattage for all channels pushed into 8 ohms, 0.1% THD: 122 per channel. It should additionally ship 130 watts into 8 ohms—driving a single channel—with solely 0.025% distortion. With a 4 ohm load that almost doubles to 250 watts whereas the distortion stays low at 0.03%.
It’s price noting that this amplifier belongs to the OSD NERO line, which additionally options 3-channel and 5-channel fashions—the XA3200 and XA5180.
Unpacking and Setup
Upon unpacking the XA7180, its stable construct and spectacular match and end made a powerful first impression. The highest plate, thicker than these on AVRs, is secured with countersunk screws that match tightly. Its development surpasses even the flagship AVRs I examined it with.
Whereas the amp can be utilized in a rack, it wants six inches of house for passive air flow. Designed primarily for shelf placement, it options built-in toes and a gorgeous design. The entrance panel options brushed aluminum and has an influence swap, the OSD emblem, and a glass panel defending the standing LEDs. This low-key, fashionable look enhances nearly any paired gear.
I employed my Denon AVR-X8500H AV receiver because the preamp/processor with the amp, powering seven of the 9 Arendal 1961 Collection tower audio system (excluding entrance wides) used in the middle of this analysis. Rated at 4 ohms impedance and 350 W most energy dealing with, the Arendals can deal with the OSD’s full output. The AVR powered the Atmos top channels on this setup.
After all should you purchase a preamp/processor versus an AVR than you completely want an amp. And you’ll most likely have an choice to make use of XLR balanced connections, which this amp helps.
Fingers-On
As a standalone amplifier with out DSP or tone controls, there’s little to debate concerning the XA7180’s operation. The amp stays silent except receiving a sign, with no speaker hiss. Whereas I lack a lab to verify its revealed specs, I detect no sound points. Clear, extremely competent amplification is a solved engineering downside, and this amp suits that description.
This high-quality Class AB amp, the commonest amplifier topology, includes a Class-H designation, indicating its use of twin voltage rails to cut back electrical energy consumption throughout low energy operation. I monitored this utilizing a Kill-a-Watt energy consumption meter.
At idle, the amp drew 58 watts and the highest reached about 85 levels. Throughout “regular listening ranges,” it consumed roughly 120 watts, demonstrating ample headroom and warming as much as round 90 levels.
The Nero’s power lies in its capability to ship extra energy to seven channels concurrently than typical AVRs, together with 13-channel flagship fashions. By relieving an AVR from powering all channels, you achieve elevated headroom and shift warmth era from the AVR to the amp.
As a matter of precept I keep away from discussing how amplifiers sound. I consider that fashionable solid-state amps, when not clipping, are successfully clear. After all there are designs which have a “signature sound” however that’s not what I search from any amp. I search ruler-flat response with inaudible THD, the probability of distinguishing between two such amps in a double-blind take a look at is low.
The XA7180’s efficiency will depend on the enter and related audio system. With well-produced audio and competent audio system, the listening expertise is enthralling. The amp isn’t the weak hyperlink. Used as a 2-channel audiophile amp with high-fidelity audio system, the sound displays the audio system’ capabilities, not the amp’s limitations.
The proof of its prowess got here after I powered a pair of the Arendal 1961 audio system full-range as if it have been a 2.0-channel audiophile stereo system. This expertise provides my hope as a result of it reveals that very excessive ranges of constancy are actually achievable with gear priced within the vary generally known as “mid-fi” however right here there’s nothing “mid” about it.
After I performed Snoop Dogg’s “Legend” from his Coolad album, the sound was tremendous tight. The vocals have been exactly targeted and holographically rendered, completely centered. The bass throbbed and was palpable. The refrain expanded, shrank and twisted in a psychedelic method. The tight snares made me faucet my foot. Snoop Dogg can afford top-notch manufacturing, and it reveals!
I noticed that operating tower audio system full-range calls for extra energy from the amp. In a multichannel system, this can be a key distinction versus utilizing an AVR. The heavy calls for of film bass – deep drones, bass sweeps and percussive explosions – can max out an AVR’s energy provide and trigger bother. With out the amp, I have a tendency to make use of a crossover and run the towers as “small” with an 80 Hz crossover to lighten the load. Nonetheless, this leaves a whole lot of bass-making functionality on the desk—fourteen woofers in seven ported cupboards, to be exact.
With the OSD amp within the combine, the system can have higher bass with extra total energy on faucet. It’s easy actually, by injecting one other 800+ watts right into a system, you’ll be able to push competent audio system additional than when simply counting on an AVR’s amps. And as a bonus, the AVR runs cooler as a result of it isn’t working almost as arduous. You might be distributing the warmth generated between two gadgets, and albeit the amp has higher air flow and extra warmth sinks than you’ll discover in any AVR.
I’m not going to get too deep into how this or that album, online game, or film “sounded” utilizing this amp. Nonetheless, throughout my evaluation, Avatar 2 was launched and though I streamed it, the sound was so energetic that my neighbor complained about their partitions shaking. This had by no means occurred earlier than. I undoubtedly observed the physicality of the sound—this amp strikes sizeable portions of air.
My new favourite pastime is taking part in Gran Turismo 7 in a racing simulator cockpit, completely centered inside a full surround-sound speaker system. The expertise is absolutely immersive when the Atmos audio matches the visuals on a 98-inch TCL 4K TV rendered in 4K Dolby Imaginative and prescient. Automotive racing is LOUD and with this amp and the quantity up excessive, I achieved the tactile acoustical features of being in a racecar going full blast and surrounded by different racecars.
The just lately remastered Grand Theft Auto On-line has Dolby Atmos sound and 4K Dolby Imaginative and prescient visuals. It’s my all-time favourite recreation with loads of visceral moments involving music, explosions and a posh mixture of sound results. All come by way of crystal clear even at close to reference ranges on the Arendal audio system.
Conclusion
This OSD amplifier gives flexibility and headroom in a rock-solid and enticing bundle at an inexpensive value. Whereas there’s nobody proper or improper option to construct a system, a superb amp is a useful gizmo—that’s the ethical of this story.
To not rain on any audiophile parades, however the Nero XA7180 proves that you just don’t want to interrupt the financial institution for nice sound and loads of energy. With 122 watts of rated energy throughout all seven channels, it delivers 854 watts for simply $850. That’s one greenback per watt of output, unquestionably a discount.
Aside from quantity, I can’t hear the distinction between the Nero XA7180 and the amps within the flagship-class AVRs I’ve. That is good, you wouldn’t wish to “match” an AVR’s sound with an exterior amp. By design and precept, they need to be impartial, clear and supply the identical flat response (so long as they’re not clipping).
Don’t overthink it. If you happen to’re searching for an excellent-sounding amp at an incredible worth, OSD must be a part of the dialog. It’s not the one nice deal on the market on a extremely competent house theater amplifier but it surely carves a candy spot for worth and efficiency. It is specs are within the Goldilocks zone, delivering simply the correct quantity of energy wanted for many house theater speaker programs attain their full potential.
Specs
Variety of Output Units: 4 per channel
Energy Bandwidth: 5Hz – 54kHz +0/-3 dB
Filter Capacitance: 4 6800μF Caps per channel
Crosstalk: >-70dB – 20Hz -20kHz
Acquire: 29dB Enter
Impedance: 40k ohms
Enter Sensitivity: 1.00 Volt
Distant Set off Voltage: 8-24v DC – 5 mA
Dimensions: together with toes (HxWxD) 6.0” x 17.0” x 16.75”
Weight: 65lbs
Energy Necessities: 120VAC, ±3%, – 60Hz 1800 watts most
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