Hifi Rose RA180 Integrated Amplifier (Silver) - Preowned/Demo

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General:
This listing is for our review sample HiFi Rose RA180 Integrated Amplifier and is preowned.

It is in perfect condition and complete with its box and manual. Of course still under new warranty.

This exact unit was featured in the videos below:

RA180 At A Glance
- Advanced Class D amplifier design with 800W output.
- Gallium Nitride FETs for perfect linear output.
- Four amplifier modules to support Bridge Tied Loads or bi-amping.
- Frequency range up to 100kHz.
- Separate outputs for two sets of stereo speakers.
- Built-in moving magnet and moving coil phono stage.
- Phono stage with adjustable EQ.
- Active crossover to support Super Tweeter frequencies.
- Tonally flat output design.
- Bass and treble tone controls.
- Bypass Power Amp mode.
- High-efficiency power supply with Silicon Carbide FET.
- Dimmable VU meters.

Product Description
Combining aesthetics from the past with technology engineered for the future, HiFi Rose RA180 is a new type of integrated amplifier that will transform your listening experience. With its illuminated meters, sleek silver chassis, and gleaming sliders and switches, its aesthetics are simultaneously retro and futuristic. The RA180 is engineered for an extremely wide frequency response (even beyond that of human hearing), to enable your system to deliver a stunningly immersive soundstage.

F4 Mono Amplifiers - Multi Output Configuration using Modules
Each channel of the RA180 amplifier is equipped with an AMP module specialized for stable bass and balance and a module specialized for soft treble and super tweeter area, with two modules. Each AMP module supports 200W (8 Ohms) and can output up to 400W per channel, for a total output of 800 watts. There are two independent modules that divide the high and low frequencies respectively, so that the speaker and, when connected, Bi-Amping has a driving force which is increased without being affected by the back electromotive force. RA180 also features BTL Mode which combines the output of two independent modules to produce a thicker and more balanced sound.

Phono Ready
The RA180 has built-in moving-magnet (MM) and moving-coil (MC) phono stages, with switch selection. It has adjustable EQ, with EQ values corresponding to curves from various record-manufacturers, using parts with a 0.1% tolerance.

Gan FET Technology
As longtime audiophiles know, amplifier design has evolved, from Class A to Class A/B to Class D. Engineers developed Class A/B to improve the high heat generation and low efficiency of Class A. Class D has higher efficiency and higher output than Class A/B, and it significantly improved the signal-to-noise ratio and THD (total harmonic distortion) characteristics, as compared to Class A and Class A/B. However, many found the sound quality to be inferior to A and A/B due to the limitations of the digital circuit. The Gallium Nitride (GaN) Advanced Class D amplifier developed by HiFi Rose has dramatically improved issues related to existing Class D technology; this was achieved by applying innovative new materials. Class D amplifiers have a topology that theoretically provides a perfect linear output at 0% distortion and 100% power efficiency. In order to achieve this, the switching action requires high speed and accuracy. However, previous products were weak compared to Class A and A/B in the linearity aspect, due to the limitations of Silicon FET, which couldn't produce ultra-smooth and natural sound. In the RA180, HiFi Rose has used a new material, GaN FET (instead of Silicon FET), to solve this problem. The dead time was dramatically improved, and a nearly perfect linear output was realized with a switching speed close to zero. This linearity goes beyond the Class D limits and produces a smooth and natural sound— like an analog amplifier.

Treble Design that Reproduced even the Super Tweeter Area
The human hearing range is known to have an upper limit of 15 - 20KHz. So why would it be necessary to build an amp with a higher range? Using modern research and experience it's now perhaps a good time to question this belief. Temporary high treble can extend well beyond 20KHz. For example, the trumpet has a frequency response that expands up to 100KHz. RA180 has an output range of 20Hz - 50Khz, 100Khz@-3dB, 200KHz @-6dB. The frequency response range is designed to be wide so that high-resolution sound sources are not filtered. This ability might be beyond human audible range, but at a wide frequency it faithfully plays the area. The depth and width of the sound and the realism will contribute to the expression.

Balanced Power Supply
The power supply that has been exclusively developed for the RA180 applies fourth-generation Silicon Carbide (SiC) FET technology to provide high output with less heat. In addition, by using a self-developed PFC (power factor circuit), it is designed to not be affected by sudden load fluctuations. The power supply device was developed to support a powerful damping factor, and the high output of 1,000 watts is designed to produce deep bass and accurate treble tones.

"The RA180 has one of the most comprehensive feature sets of any high-end amplifier currently on the current market and makes an ideal partner to the brand’s award-winning music streamers.". - Mark Sparrow, Forbes

SkyFi Cosmetic Notes:
No sings of visible cosmetic wear. Great condition.

Ownership:
Single Owner

Connections:
Audio input: Balanced XLR Line Input x1, Unbalanced RCA Line Input x 3, MM/MC (switchable) Phono Input x 1, COAX x 1, USB Audio In x1

Audio output: Subwoofer Out x 1

Cosmetic Condition:
New = Factory sealed and unopened. See our detailed rating description here.

Working Condition:
Working perfectly and tested in our lab and listening room.

Included:
Complete Kit as it Left the Factory

Packing:
Original Manufacturers Packing

Original MSRP:
$6,995.00

Specs:
Finish: High Purity Aluminium
Power
Amplifier Output: 4 Ohms 200W x 4ch (800W)
Amplifier Output: 8 Ohms 200W x 4ch (880W)
Amplifier Output: BTL Mode On 400W x 2ch (400W)
Input Sensitivity: Balanced Input 2000mV
Input Sensitivity: Unbalanced (Line 1, 2, 3) Input 1000mV
Input Sensitivity: Phono (MC/MM) Input 5mV / 0.5mV
Impedance Input: Balanced Input 44k Ohms
Impedance Input: Unbalanced (Line 1, 2, 3) Input 47k Ohms
Impedance Input: Phono (MM/MC) Input 47k Ohms
Bandwidth (0dBr +- 3dB / 8 Ohm): Speaker Output 10Hz - 90kHz
Bandwidth (0dBr +- 3dB / 8 Ohm): H/F Speaker Output 10Hz - 90kHz
Frequency Response (1W, 0 +- 1dB / 8 Ohm): Speaker Output 10Hz - 90kHz
Frequency Response (1W, 0 +- 1dB / 8 Ohm): H/F Speaker Output 10Hz - 90kHz
THD Measure: Balanced and Unbalanced (Line 1, 2, 3) Input 0.005% (50W)
Damping Factor: Speaker and H/F Speaker Output >150
Signal to Noise Ratio (S/N): BTL / Balanced, Unbalanced / Phono MM, MC 107dB / 105dB / 80dB (MM), 60dB (MC)
Impedance Output: Speaker Output 53m Ohm
Subsonic Filter with On/Off Switch: -3dB 50Hz
Tone Control with On/Off Switch: Bass (100Hz) / Treble (10kHz) +- 15dB
X-Over with On/Off Switch: HPF (-3dB) 600Hz - 6kHz
Phono Turnover Flat
Phono Turnover 300Hz (+7.7dB @100Hz)
Phono Turnover 400Hz (+11.7dB @100Hz)
Phono Turnover 500Hz (+13dB @ 100Hz)
Phono Turnover 700Hz (+14.5db @ 100hz)
Phono Roll-Off Flat
Phono Roll-Off 1.6kHz (-16dB @ 10kHz)
Phono Roll-Off 2.1kHz (-13.7dB @ 10kHz)
Phono Roll-Off 3.18kHz (-11dB @ 10kHz
Phono Roll-Off 3.4kHz (-8dB @ 10kHz)
Phono Roll-Off 6.36kHz (-5dB @ 10kHz)
Power: Power SMPS (800W)
Power: Voltage AC100-230v, 50 / 60Hz
Audio In / Out on Rear: Trigger Trigger Voltage Can be turned On: 3.3v - 12v
Remote Control: IR Input 38kHz Infrared Ray (Within 10m of operating distance)

Dimensions:
16.9" W x 13.7" D x 4.3" H

Weight:
36.8 lbs.

Recommended Cables:
Kimber Kable - RCA Interconnects - Better

Kimber Kable - RCA Interconnects - Best

Kimber Kable - Phono Interconnects

Kimber Kable - BALANCED XLR Connectors - Better

Kimber Kable - BALANCED XLR Connectors - Best

Kimber Kable - Speaker Cables - Better

Kimber Summit Series Monocle XL Speaker Cables (PAIR) - Best

Kimber Summit Series BiFocal XL Bi-Wire Speaker Cables (PAIR) - Best If Applicable

Kimber Kable - Power Cords - Better

Kimber Kable - Power Cords - Best

Testing Process:
We start with a visual inspection of all internal components to make sure that there are no signs of heat stress or damage. Capacitors are checked for telltale signs of predictive failure including bulging, shrunken wrappers, or physical leakage. We also inspect the PCBs for discoloration from resistors or transistors that may have been running hot. On vintage units we often spot check select capacitors for value and ESR.

If the device has the ability to decouple the preamplifier from the power amplifier, we remove the jumpers and independently test each section. If the device cannot be decoupled, we assess the electronic condition of the piece by analyzing the speaker level output only.

We start by connecting the "Pre-Out" jacks of the integrated to a Sencore PA81 Power Analyzer which simulates real world loading conditions and gives us an oscilloscope interface. The first order of business is checking that the volume control works smoothly throughout its entire range with acceptable channel balance. This is accomplished by feeding a 1 KHz sine wave into one of the preamp’s line level inputs while monitoring the preamp’s output on an oscilloscope.

We then switch to a 1 KHz square wave to test the tone controls, loudness function, and filters where applicable. During this step we are watching for equal alteration of the test signal by both channels. This also helps us identify dirty controls that will need treatment.

Once the basic line stage functions are verified, we test each input individually. This is especially important for devices that use relays to select their sources.

If the preamp section is equipped with a phono stage we test that as well. We use an inverse RIAA filter which allows us to feed a reference test signal into the phono input with the proper RIAA equalization and level. A square wave or sine sweep is used to verify that the device’s phono stage is faithfully reproducing the RIAA curve.

Next we test the power amplifier section by connecting the integrated amplifier speaker outputs to a Sencore PA81 Power Analyzer which acts as a dummy load, DC offset monitor, and oscilloscope interface. We start with a low level 1 KHz test signal at the "Main In” jacks and slowly increase its amplitude while monitoring the output on an oscilloscope for signs of noise, clipping, distortion, or improper channel balance. We continue increasing the signal level until the amplifier reaches clipping.

At this point we take an output power measurement and compare it to the spec sheet of the amplifier to verify proper performance. We finish off the bench evaluation with a 1 KHz square wave check and a 20 Hz to 20 KHz sine sweep to assess the amplifier’s frequency response characteristics.

This battery of tests will usually reveal if the amplifier has any issues that need further attention.

If the preamp and power amp both pass these tests, we reconnect the sections and verify that the preamp section can drive the power amp to rated power with a 1KHz tone on one of the line level inputs.

Before the device leaves the bench, we perform a listening test with actual music using a variety of preferred test tracks. Our benches are outfitted with familiar monitor speakers which help us identify inconsistencies that will not always show up on our test gear. The main things that we are listening for are hum or noise with no signal present, proper center image, clicks, pops, or any other obvious undesirable audio characteristics.

If the unit passes all of these tests it moves to our long term testing rig where we simulate real word operating conditions for 6-8 hours minimum. This allows us to monitor the unit for signs of thermal runaway or intermittent issues that only crop up when the unit has fully come up to temperature.