Link: reviewed by Roger Kanno on *SoundStage! Hi-Fi* on June 15, 2023

**General Information**

All measurements taken using an Audio Precision APx555 B Series analyzer.

The Yamaha R-N2000A was conditioned for 1 hour at 1/8th full rated power (~11W into 8 ohms) before any measurements were taken. All measurements were taken with both channels driven, using a 120V/20A dedicated circuit, unless otherwise stated.

The R-N2000A offers three unbalanced line-level analog inputs (RCA), one unbalanced phono input (RCA) for a moving-magnet (MM) cartridge, one coaxial (RCA) and two optical (TosLink) S/PDIF digital inputs, a Bluetooth input, one line-level subwoofer output (RCA), two line-level pre-outs (RCA), and two pair of speaker-level outputs (A and B). On the front of the unit is a 1/4″ TRS headphone output, and a Pure Direct button, which, when engaged, disables all DSP and tone controls. For the purposes of these measurements, the following inputs were evaluated: digital coaxial, and the analog line-level and MM unbalanced inputs, with the Pure Direct switch engaged.

Most measurements were made with a 2Vrms line-level analog input, 5mVrms MM input, and 0dBFS digital input. The signal-to-noise ratio (SNR) measurements were made with the same input-signal values but with the volume set to achieve the rated output power of 90W (8 ohms). For comparison, on the line-level input, a SNR measurement was also made with the volume at maximum, but with a lower input voltage to achieve the same 90W output.

Based on the accuracy and non-repeatable results at various volume levels of the left/right channel matching (see table below), the R-N2000A volume control is likely digitally controlled but operating in the analog domain. The volume control offers a total range from -53.6dB to +42.7dB between the line-level analog input and the speaker outputs in 0.5dB steps.

The analyzer’s input bandwidth filter was set to 10Hz –22.4kHz for all measurements, except for frequency response (DC to 1MHz), FFTs (10Hz to 90kHz), and THD vs. frequency (10Hz –90kHz). The latter to capture the second and third harmonic of the 20kHz output signal. Since the R-N2000A is a conventional class-AB amp, there was no issue with excessive noise above 20kHz like there would be with a class-D design.

**Volume-control accuracy (measured at speaker outputs): left-right channel tracking**

Volume position | Channel deviation |

-96.5dB (min) | 0.004dB |

-80dB | 0.036dB |

-70dB | 0.04dB |

-60dB | 0.045dB |

-50dB | 0.045dB |

-40dB | 0.025dB |

-30dB | 0.022dB |

-20dB | 0.028dB |

-10dB | 0.008dB |

max (0dB) | 0.02dB |

**Published specifications vs. our primary measurements**

The table below summarizes the measurements published by Yamaha for the R-N2000A compared directly against our own. The published specifications are sourced from Yamaha’s website, either directly or from the manual available for download, or a combination thereof. With the exception of frequency response, where the Audio Precision bandwidth was extended from DC to 1MHz, assume, unless otherwise stated, 10W into 8ohms and a measurement input bandwidth of 10Hz to 22.4kHz, and the worst-case measured result between the left and right channels.

Parameter | Manufacturer | SoundStage! Lab |

Rated output power into 8 ohms (0.07% THD) | 90W | 86W |

Rated output power into 4 ohms (0.07% THD) | 145W | 141W |

Maximum power (8 ohms, 10% THD) | 120W | 108W |

IHF Burst Power (8/4 ohms) | 100/185W | 100.7/181.4W |

Frequency response (5Hz - 100kHz) | 0/-3dB | -0.1/-0.56dB |

SNR (A-weighted, rated output, CD input) | 110dB | 111.6dB |

Our primary measurements revealed the following using the line-level analog input and digital coaxial input (unless specified, assume a 1kHz sinewave at 2Vrms or 0dBFS, 10W output, 8-ohm loading, 10Hz to 22.4kHz bandwidth):

Parameter | Left channel | Right channel |

Maximum output power into 8 ohms (1% THD+N, unweighted) | 90W | 90W |

Maximum output power into 4 ohms (1% THD+N, unweighted) | 149W | 149W |

Maximum burst output power (IHF, 8 ohms) | 100.7W | 100.7W |

Maximum burst output power (IHF, 4 ohms) | 181.4W | 181.4W |

Continuous dynamic power test (5 minutes, both channels driven) | passed | passed |

Crosstalk, one channel driven (10kHz) | -80.1dB | -90.6dB |

Damping factor | 279 | 295 |

Clipping no-load output voltage | 29.7Vrms | 29.7Vrms |

DC offset | <-9.8mV | <-2.7mV |

Gain (pre-out) | 14.3dB | 14.4dB |

Gain (maximum volume) | 42.7dB | 42.7dB |

IMD ratio (CCIF, 18kHz + 19kHz stimulus tones, 1:1) | <-75dB | <-75dB |

IMD ratio (SMPTE, 60Hz + 7kHz stimulus tones, 4:1 ) | <-71dB | <-71dB |

Input impedance (line input, RCA) | 54.6k ohms | 55.4k ohms |

Input sensitivity (for rated power, maximum volume) | 200mVrms | 200mVrms |

Noise level (with signal, A-weighted) | <69uVrms | <72uVrms |

Noise level (with signal, 20Hz to 20kHz) | <97uVrms | <208uVrms |

Noise level (no signal, A-weighted, volume min) | <49uVrms | <49uVrms |

Noise level (no signal, 20Hz to 20kHz, volume min) | <63uVrms | <72uVrms |

Output Impedance (pre-out) | 1325 ohms | 1326 ohms |

Signal-to-noise ratio (90W, A-weighted, 2Vrms in) | 111.6dB | 111.7dB |

Signal-to-noise ratio (90W, 20Hz to 20kHz, 2Vrms in) | 109.5dB | 108.9dB |

Signal-to-noise ratio (90W, A-weighted, max volume) | 100.4dB | 100.4dB |

Dynamic range (90W, A-weighted, digital 24/96) | 111.2dB | 111.4dB |

Dynamic range (90W A-weighted, digital 16/44.1) | 96.0dB | 95.9dB |

THD ratio (unweighted) | <0.0054% | <0.0054% |

THD ratio (unweighted, digital 24/96) | <0.0063% | <0.0058% |

THD ratio (unweighted, digital 16/44.1) | <0.0063% | <0.0058% |

THD+N ratio (A-weighted) | <0.0061% | <0.0061% |

THD+N ratio (A-weighted, digital 24/96) | <0.0062% | <0.0062% |

THD+N ratio (A-weighted, digital 16/44.1) | <0.0069% | <0.0066% |

THD+N ratio (unweighted) | <0.0055% | <0.0058% |

Minimum observed line AC voltage | 123.4VAC | 123.4VAC |

For the continuous dynamic power test, the R-N2000A was able to sustain 170W into 4 ohms (~3% THD) using an 80Hz tone for 500ms, alternating with a signal at -10dB of the peak (17W) for 5 seconds, for 5 continuous minutes without inducing a fault or the initiation of a protective circuit. This test is meant to simulate sporadic dynamic bass peaks in music and movies. During the test, the top of the R-N2000A was only slightly warm to the touch.

Our primary measurements revealed the following using the phono-level input, MM configuration (unless specified, assume a 1kHz 5mVrms sinewave input, 10W output, 8-ohm loading, 10Hz to 22.4kHz bandwidth):

Parameter | Left channel | Right channel |

Crosstalk, one channel driven (10kHz) | -75.3dB | -71.4dB |

DC offset | <-8mV | <-1mV |

Gain (default phono preamplifier) | 35.3dB | 35.3dB |

IMD ratio (CCIF, 18kHz + 19kHz stimulus tones, 1:1) | <-69dB | <-69dB |

IMD ratio (CCIF, 3kHz + 4kHz stimulus tones, 1:1) | <-74dB | <-74dB |

Input impedance | 53.1k ohms | 52.3k ohms |

Input sensitivity (to max power with max volume) | 3.4mVrms | 3.4mVrms |

Noise level (with signal, A-weighted) | <860uVrms | <860uVrms |

Noise level (with signal, 20Hz to 20kHz) | <2.4mVrms | <2.4mVrms |

Noise level (no signal, A-weighted, volume min) | <49uVrms | <49uVrms |

Noise level (no signal, 20Hz to 20kHz, volume min) | <63uVrms | <63uVrms |

Overload margin (relative 5mVrms input, 1kHz) | 23.4dB | 23.3dB |

Signal-to-noise ratio (90W, A-weighted, 5mVrms in) | 79.2dB | 79.3dB |

Signal-to-noise ratio (90W, 20Hz to 20kHz, 5mVrms in) | 71.6dB | 71.8dB |

Signal-to-noise ratio (90W, A-weighted, max volume) | 75.8dB | 75.8dB |

THD (unweighted) | <0.0088% | <0.0088% |

THD+N (A-weighted) | <0.014% | <0.014% |

THD+N (unweighted) | <0.03% | <0.03% |

Our primary measurements revealed the following using the analog input at the headphone output (unless specified, assume a 1kHz sinewave, 2Vrms output, 300 ohms loading, 10Hz to 22.4kHz bandwidth):

Parameter | Left channel | Right channel |

Maximum output power into 600 ohms (1% THD+N, unweighted) | 48mW | 48mW |

Maximum output power into 300 ohms (1% THD+N, unweighted) | 60mW | 60mW |

Maximum output power into 32 ohms (1% THD+N, unweighted) | 26mW | 26mW |

Gain | 32.3dB | 32.3dB |

Output impedance | 97.7 ohms | 98.5 ohms |

Noise level (no signal, A-weighted, volume min) | <11uVrms | <11uVrms |

Noise level (no signal, 20Hz to 20kHz, volume min) | <14uVrms | <14uVrms |

Signal-to-noise ratio (Max Output, A-weighted, 2Vrms in) | 107.1dB | 107.1dB |

Signal-to-noise ratio (Max Output, 20Hz to 20kHz, 2Vrms in) | 105.0dB | 105.0dB |

THD ratio (unweighted) | <0.0079% | <0.0071% |

THD+N ratio (A-weighted) | <0.0091% | <0.0081% |

THD+N ratio (unweighted) | <0.0081% | <0.0072% |

**Frequency response (8-ohm loading, line-level input, relative level)**

In our measured frequency response chart above, the blue and red plots show the speaker-level outputs (relative to 1kHz, at 10W into 8 ohms), while the purple plot (relative to 20Hz) is the line-level subwoofer output. The R-N2000A’s speaker outputs are essentially flat within the audioband (0dB at 20Hz, -0.04dB at 20kHz), and show an extended bandwidth (-0.1dB at 5Hz, -0.44dB at 80kHz). The subwoofer output is low-pass filtered, with a -3dB point at roughly 500Hz and a 12dB/octave slope. In the graph above and most of the graphs below, only a single trace may be visible. This is because the left channel (blue or purple trace) is performing identically to the right channel (red or green trace), and so they perfectly overlap, indicating that the two channels are ideally matched.

**Frequency response (8-ohm loading, line-level input, Pure Direct off)**

The measured frequency response (relative to 1kHz) chart above shows the R-N2000A speaker-level outputs (10W into 8 ohms) with the Pure Direct switch disengaged. In this mode, the analog signal is digitized at what likely is a 96kHz sample rate (-3dB point just past 40kHz). At the extremes of the audioband, the response is at roughly -0.25dB at both 20Hz and 20kHz.

**Frequency response (8-ohm loading, line-level input, bass and treble controls)**

Above are frequency response plots (relative to 1kHz) measured at the speaker-level outputs into 8 ohms, with the bass and treble controls set to maximum (blue/red plots) and minimum (purple/green plots). We see that for the bass and treble controls, roughly +/-9dB respectively of gain/cut are available at 20Hz and 20kHz.

**Phase response (line-level input)**

Above is the phase response plot from 20Hz to 20kHz for the line-level input, measured across the speaker outputs at 10W into 8 ohms. The R-N2000A does not invert polarity. Here we find essentially no phase shift within the audioband, owing to the R-N2000A’s extended bandwidth.

**Frequency response vs. input type (8-ohm loading, left channel only)**

The chart above shows the R-N2000A’s frequency response (relative to 1kHz) as a function of input type measured across the speaker outputs at 10W into 8 ohms. The blue trace is for a 16-bit/44.1kHz dithered digital input signal from 10Hz to 22kHz using the coaxial digital input, and the purple trace is for a 24/96 dithered digital input signal from 10Hz to 48kHz, while the pink trace is for a 24/192 dithered digital input signal from 10Hz to 96kHz. The green trace is the same analog input frequency response seen above. The 16/44.1 data exhibits not quite brick-wall-type filtering, with a -3dB point at 19.7kHz. The 24/96 and 24/192 kHz data yielded -3dB points at 42.3kHz and 80.8kHz, respectively.

**Frequency response (8-ohm loading, MM phono input)**

The chart above shows the frequency response (relative to 1kHz) for the MM phono input. What is shown is the deviation from the RIAA curve, where the input signal sweep is EQ’d with an inverted RIAA curve supplied by Audio Precision (*i.e.*, zero deviation would yield a flat line at 0dB). We see maximum deviations within about ±0.1dB from 20Hz to 20kHz.

**Phase response (MM input)**

Above is the phase response plot from 20Hz to 20kHz for the MM phono input, measured across the speaker outputs at 10W into 8 ohms. The R-N2000A does not invert polarity. For the phono input, since the RIAA equalization curve must be implemented, which ranges from +19.9dB (20Hz) to -32.6dB (90kHz), phase shift at the output is inevitable. Here we find a worst case of about -60 degrees at 200Hz and 5kHz.

**Digital linearity (16/44.1 and 24/96 data)**

The chart above shows the results of a linearity test for the coaxial digital input for both 16/44.1 (blue/red) and 24/96 (purple/green) input data, measured at the line-level pre-outs of the R-N2000A for a 1.93Vrms (at 0dBFS) output signal. The digital input is swept with a dithered 1kHz input signal from -120dBFS to 0dBFS, and the output is analyzed by the APx555. The ideal response would be a straight flat line at 0dB. Both data were essentially perfect as of -100dBFS down to 0dBFS. At -120dBFS, the 16/44.1 data were about +2dB (left/right) above reference, while the 24/96 data were still at the reference 0dB level. To verify the performance of the 24/96 data, we extended the sweep down to . . .

. . . -140dB. The chart above shows that the 24/96 data yielded worst-case deviations of +2dB above reference, even at -140dB. This is an exceptional result. The 16/44.1 data deviates substantially, which is expected.

**Impulse response (24/44.1 data)**

The graph above shows the impulse response for a looped 24/44.1 test file that moves from digital silence to full 0dBFS (all “1”s) for one sample period then back to digital silence, measured at the fixed line-level pre-outs of R-N2000A. We can see that the R-N2000A utilizes a typical symmetrical sinc function reconstruction filter.

**J-Test (coaxial)**

The chart above shows the results of the J-Test test for the coaxial digital input measured at the line-level pre-outs of the R-N2000A. J-Test was developed by Julian Dunn in the 1990s. It is a test signal—specifically, a -3dBFS undithered 12kHz squarewave sampled (in this case) at 48kHz (24 bits). Since even the first odd harmonic (*i.e.*, 36kHz) of the 12kHz squarewave is removed by the bandwidth limitation of the sampling rate, we are left with a 12kHz sinewave (the main peak). In addition, an undithered 250Hz squarewave at -144dBFS is mixed with the signal. This test file causes the 22 least significant bits to constantly toggle, which produces strong jitter spectral components at the 250Hz rate and its odd harmonics. The test file shows how susceptible the DAC and delivery interface are to jitter, which would manifest as peaks above the noise floor at 500Hz intervals (*e.g.*, 250Hz, 750Hz, 1250Hz, etc.). Note that the alternating peaks are in the test file itself, but at levels of -144dBrA and below. The test file can also be used in conjunction with artificially injected sinewave jitter by the Audio Precision, to show how well the DAC rejects jitter.

The coaxial input exhibits a few low-level peaks in the audioband, most of which are under -140dBrA. This is a strong J-test result, indicating that the R-N2000A DAC should be adequate at rejecting jitter.

**J-Test (optical)**

The chart above shows the results of the J-Test test for the optical digital input measured at the fixed line-level pre-outs of the R-N2000A. Essentially the same result as with the coax input can be seen.

**J-Test with 100ns of injected jitter (coaxial)**

Both the coaxial and optical inputs were also tested for jitter immunity by injecting artificial sinewave jitter at 2kHz, which would manifest as sidebands at 10kHz and 14kHz without any jitter rejection. The optical input jitter result was very similar to the coaxial input result shown above. Jitter immunity proved strong. Although sidebands were visible at the 100ns jitter level, they did not exceed -145dBrA in amplitude.

**J-Test with 500ns of injected jitter (coaxial)**

Both the coaxial and optical inputs were also tested for jitter immunity by injecting artificial sinewave jitter at 2kHz, which would manifest as sidebands at 10kHz and 14kHz without any jitter rejection. The optical input jitter result was very similar to the coaxial input result shown above. Jitter immunity again proved to be solid but not perfect, with visible sidebands at a very low -135dBrA at the 300ns jitter level. The R-N2000A DAC did lose sync with the signal when jitter was increased beyond approximately 400ns.

**Wideband FFT spectrum of white noise and 19.1kHz sinewave tone (coaxial input)**

The plot above shows a fast Fourier transform (FFT) of the R-N2000A’s line-level pre-outs with white noise at -4 dBFS (blue/red), and a 19.1 kHz sinewave at 0dBFS fed to the coaxial digital input, sampled at 16/44.1. The medium roll-off above 20kHz in the white-noise spectrum shows the implementation of a reconstruction filter that isn’t quite as steep as a typical brickwall type. There are two clear aliased image peaks in the audio band above the -135dBrA noise floor at 13kHz (-95dBrA) and 6kHz (-115dBrA). The main 25kHz alias peak is only mildly suppressed at -30dBrA. The second, third, and fourth distortion harmonics (38.2, 57.3, 76.4kHz) of the 19.1kHz tone are between -65dBrA and -90dBrA.

**RMS level vs. frequency vs. load impedance (1W, left channel only)**

The chart above shows RMS level (relative to 0dBrA, which is 1W into 8ohms or 2.83Vrms) as a function of frequency, for the analog line-level input swept from 5Hz to 100kHz. The blue plot is into an 8-ohm load, the purple is into a 4-ohm load, the pink plot is an actual speaker (Focal Chora 806, measurements can be found here), and the cyan plot is no load connected. The chart below . . .

. . . is the same but zoomed in to highlight differences. Here we can see only minor deviations of about 0.06dB from 4 ohms to no load through most of the audioband, reaching as high as 0.17dB at 20kHz. This is an indication of a relatively high damping factor, or low output impedance. The variations in RMS level when a real speaker was used are smaller, deviating by at worst 0.04dB through most of the audioband.

**THD ratio (unweighted) vs. frequency vs. output power**

The chart above shows THD ratios at the output into 8 ohms as a function of frequency for a sinewave stimulus at the analog line-level input. The blue and red plots are for left and right channels at 1W output into 8 ohms, purple/green at 10W, and pink/orange at 80W. The power was varied using the volume control. At 1W, THD ratios ranged from 0.007% at 20Hz, down to 0.002% at 6kHz. At 1 and 10W, THD ratios were similar, and the right channel outperformed the left by 3–5dB. Right channel THD ratios ranged from about 0.006% at 20Hz, down to 0.004–0.005% from 50Hz to 3kHz, then up to just above 0.01% at 20kHz. The 80W THD values were slightly higher and ranged from 0.008% at 20Hz through to about 3kHz, then up to 0.03% at 20kHz.

**THD ratio (unweighted) vs. frequency at 10W (MM input)**

The chart above shows THD ratios as a function of frequency plots for the MM phono input measured across an 8-ohm load at 10W. The input sweep is EQ’d with an inverted RIAA curve. The THD values vary from around 0.02% (20Hz) down to 0.005% at 300–2kHz, then up to 0.03% at 20kHz.

**THD ratio (unweighted) vs. output power at 1kHz into 4 and 8 ohms**

The chart above shows THD ratios measured at the output of the R-N2000A as a function of output power for the analog line level-input, for an 8-ohm load (blue/red for left/right channels) and a 4-ohm load (purple/green for left/right channels). The 8-ohm and right channel 4-ohm data track perfectly from 50mW to 3W, ranging from 0.002% to 0.005%. The left channel 4-ohm data were 5-10dB higher in this range. From 3W to 30W, there is jump in THD from the right channel 4-ohm data, by about 10dB. This phenomenon was repeatable. At 50W to about 80W, all THD data were nearly identical at about 0.07%. The “knee” for the 8-ohm data is around 70W, then up to the 1% THD mark at the rated 90W. With a 4-ohm load, the “knee” occurs at about 130W, and the 1% THD value was reached at 149W.

**THD+N ratio (unweighted) vs. output power at 1kHz into 4 and 8 ohms**

The chart above shows THD+N ratios measured at the output of the R-N2000A as a function of output power for the analog line level-input, for an 8-ohm load (blue/red for left/right channels) and a 4-ohm load (purple/green for left/right channels). Overall, THD+N values for both loads were similar (with the exception of the 10dB jump in THD from the right channel into 4 ohms from 3W to 30W), ranging from about 0.02%, down to just above 0.005% (8-ohm). The 4-ohm left channel THD+N ratios were a few dB worse than the 8-ohm ratios through most of the sweep.

**THD ratio (unweighted) vs. frequency at 8, 4, and 2 ohms (left channel only)**

The chart above shows THD ratios measured at the output of the R-N2000A as a function of frequency into three different loads (8/4/2 ohms) for a constant input voltage that yielded 10W at the output into 8 ohms (and roughly 20W into 4 ohms, and 40W into 2 ohms) for the analog line-level input. The 8-ohm load is the blue trace, the 4-ohm load the purple trace, and the 2-ohm load the pink trace. We find all three traces yielding similar results, remarkably, with the 2-ohm THD data out-performing the 4-ohm data by 2–3dB, and nearly matching the 8-ohm data. The exception is at 20Hz and 20kHz, where the 2-ohm data were about 5dB worse than the 8-ohm. We find the 8-ohm trace ranging from 0.005% from 20Hz up to 3kHz, then up to 0.02% at 20kHz. These data show that the R-N2000A is not only stable into 2-ohm loads, but will perform nearly identically, in terms of THD, to an 8-ohm load.

**THD ratio (unweighted) vs. frequency into 8 ohms and real speakers (left channel only)**

The chart above shows THD ratios measured at the output of the R-N2000A as a function of frequency into an 8-ohm load and two different speakers for a constant output voltage of 2.83Vrms (1W into 8 ohms) for the analog line-level input. The 8-ohm load is the blue trace, the purple plot is a two-way speaker (Focal Chora 806, measurements can be found here), and the pink plot is a three-way speaker (Paradigm Founder Series 100F, measurements can be found here). At lower frequencies, the two-way speaker yielded the highest THD ratios, as high as 0.05% at 20Hz, but as low as 0.0015% at 2-3kHz. Overall, however, THD ratios were mostly within 5dB of the 8-ohm THD data, sometimes above, sometimes below. This shows once again, that the R-N2000A will yield consistent and stable THD results into different loads.

**IMD ratio (CCIF) vs. frequency into 8 ohms and real speakers (left channel only)**

The chart above shows intermodulation distortion (IMD) ratios measured at the output of the R-N2000A as a function of frequency into an 8-ohm load and two different speakers for a constant output voltage of 2.83Vrms (1W into 8 ohms) for the analog line-level input. Here the CCIF IMD method is used, where the primary frequency is swept from 20kHz (F1) down to 2.5kHz, and the secondary frequency (F2) is always 1kHz lower than the primary, with a 1:1 ratio. The CCIF IMD analysis results are the sum of the second- (F1-F2 or 1kHz) and third-modulation products (F1+1kHz, F2-1kHz). The 8-ohm load is the blue trace, the purple plot is a two-way speaker (Focal Chora 806, measurements can be found here), and the pink plot is a three-way speaker (Paradigm Founder Series 100F, measurements can be found here). The results for the dummy load were fairly consistent, hovering around 0.01% throughout the sweep. We find that the two-way speaker yielded IMD ratios 5-15dB lower than the dummy load, ranging from 0.002% at 2.5kHz and 0.005% at 20kHz. The 3-way speaker yielded IMD ratios roughly 10dB lower than the dummy load at lower frequences, and 5dB higher at higher frequencies.

**IMD ratio (SMPTE) vs. frequency into 8 ohms and real speakers (left channel only)**

The chart above shows IMD ratios measured at the output of the R-N2000A as a function of frequency into an 8-ohm load and two different speakers for a constant output voltage of 2.83Vrms (1W into 8 ohms) for the analog line-level input. Here, the SMPTE IMD method is used, where the primary frequency (F1) is swept from 250Hz down to 40Hz, and the secondary frequency (F2) is held at 7kHz with a 4:1 ratio. The SMPTE IMD analysis results consider the second (F2 ± F1) through the fifth (F2 ± 4xF1) modulation products. The 8-ohm load is the blue trace, the purple plot is a two-way speaker (Focal Chora 806, measurements can be found here), and the pink plot is a three-way speaker (Paradigm Founder Series 100F, measurements can be found here). All three results are similar, at or below the 0.02% level. The two-way speaker IMD result dipped as low as 0.006% at 80Hz, while the three-way speaker IMD result dipped as low as 0.008% just below 60Hz.

**FFT spectrum – 1kHz (line-level input)**

Shown above is the fast Fourier transform (FFT) for a 1kHz input sinewave stimulus, measured at the output across an 8-ohm load at 10W for the analog line-level input. We see that the signal’s third harmonic (3kHz) dominates at around -85dBrA, or 0.006%. The other signal harmonics are around or below -100dBrA, or 0.001%. There are clearly visible power-supply related noise peaks at even and odd harmonics (60Hz, 120Hz, 180Hz, 240Hz, etc.) on the left side of the main 1kHz peak, with the 120Hz peak dominating at -110/-95dBrA (left/right), or 0.0003/0.002%.

**FFT spectrum – 1kHz (line-level input, Pure Direct off)**

Shown above is the fast Fourier transform (FFT) for a 1kHz input sinewave stimulus, measured at the output across an 8-ohm load at 10W for the analog line-level input, with the Pure Direct switch disengaged (incoming analog signal digitized). Compared to the FFT above, with Pure Direct engaged, signal distortion peaks are higher here, with the third harmonic (3kHz) reaching almost -75dBrA, or 0.02%, compared to the -85dBrA seen in the FFT above. Power-supply-related noise peaks are similar here compared to the FFT above; however, the 60Hz peak is slightly more predominant here at -110dBrA, or 0.0003%, versus the -115dBrA seen above with Pure Direct engaged. We can also see here, the peaks at 96kHz from the sample rate used to digitize the incoming analog signal.

**FFT spectrum – 1kHz (digital input, 16/44.1 data at 0dBFS)**

Shown above is the fast Fourier transform (FFT) for a 1kHz input sinewave stimulus, measured at the output across an 8-ohm load at 10W for the coaxial digital input, sampled at 16/44.1. The signal and noise-related harmonics are very similar to the FFT above for the analog input, with the exception of the levels for the second (2kHz) and third (3kHz) signal harmonics. Here we find them both at about -90dBrA, or 0.003%, versus the -100dBrA (2kHz) and -85dBrA (3kHz) levels seen in the analog input FFT.

**FFT spectrum – 1kHz (digital input, 24/96 data at 0dBFS)**

Shown above is the fast Fourier transform (FFT) for a 1kHz input sinewave stimulus, measured at the output across an 8-ohm load at 10W for the coaxial digital input, sampled at 24/96. The signal and noise-related harmonics are very similar to the 16/44.1 FFT above, but for a slightly lower noise here due to the 24-bit depth.

**FFT spectrum – 1kHz (digital input, 16/44.1 data at -90dBFS)**

Shown above is the FFT for a 1kHz -90dBFS dithered 16/44.1 input sinewave stimulus at the coaxial digital input, measured at the output across an 8-ohm load. We see the 1kHz primary signal peak, at the correct amplitude, and non-existent signal harmonics. Power-supply related noise peaks can be seen at the fundamental (60Hz) and higher harmonics, at -105dBrA, or 0.0006%, and below.

**FFT spectrum – 1kHz (digital input, 24/96 data at -90dBFS)**

Shown above is the FFT for a 1kHz -90dBFS dithered 24/96 input sinewave stimulus at the coaxial digital input, measured at the output across an 8-ohm load. We see the 1kHz primary signal peak, at the correct amplitude, and virtually non-existent signal harmonics. Power-supply-related noise peaks can be seen at the fundamental (60Hz) and higher harmonics, at -105dBrA, or 0.0006%, and below.

**FFT spectrum – 1kHz (MM phono input)**

Shown above is the FFT for a 1kHz input sinewave stimulus, measured at the output across an 8-ohm load at 10W for the MM phono input. We see that the signal’s third harmonic (3kHz) dominates at around -85dBrA, or 0.006%. The 2kHz peak is very low at -110dBrA, or 0.0003%, and subsequent signal harmonics are at -95dBrA, or 0.002%, and below. There are clearly visible power-supply-related noise peaks on the left side of the main 1kHz peak, with the 60Hz fundamental dominating at -90/-80dBrA (left/right channels), or 0.003/0.01%.

**FFT spectrum – 50Hz (line-level input)**

Shown above is the FFT for a 50Hz input sinewave stimulus measured at the output across an 8-ohm load at 10W for the analog line-level input. The X axis is zoomed in from 40Hz to 1kHz, so that peaks from noise artifacts can be directly compared against peaks from the harmonics of the signal. We see that the signal’s third harmonic (150Hz) dominates at around -90dBrA, or 0.003%. The second signal harmonic (100Hz), and subsequent signal harmonic peaks, are at or below -100dBrA, or 0.001%. There are clearly visible power-supply-related noise peaks at even and odd harmonics (60Hz, 120Hz, 180Hz, 240Hz, etc.) on the left side of the main 1kHz peak, with the 120Hz peak dominating at -110/-95dBrA (left/right channels), or 0.0003/0.002%.

**FFT spectrum – 50Hz (MM phono input)**

Shown above is the FFT for a 50Hz input sinewave stimulus measured at the output across an 8-ohm load at 10W for the MM phono input. The X axis is zoomed in from 40 Hz to 1kHz, so that peaks from noise artifacts can be directly compared against peaks from the harmonics of the signal. We see that the signal’s third harmonic (150Hz) dominates at around -85dBrA, or 0.006%. The even-order signal harmonic (100, 200Hz, etc.) are barely perceptible above the -110 to -120dBrA noise floor, and subsequent odd-order signal harmonic peaks (250Hz, 350Hz, etc.) are at or below -100dBrA, or 0.001%. The most dominant power-supply-related noise peak is at the fundamental (60Hz) at -80dBrA (right channel), or 0.01%.

**Intermodulation distortion FFT (18kHz + 19kHz summed stimulus, line-level input)**

Shown above is an FFT of the intermodulation distortion (IMD) products for an 18kHz + 19kHz summed sinewave stimulus tone measured at the output across an 8-ohm load at 10W for the analog line-level input. The input RMS values are set at -6.02dBrA so that, if summed for a mean frequency of 18.5kHz, would yield 10W (0dBrA) into 8 ohms at the output. We find that the second-order modulation product (*i.e.*, the difference signal of 1kHz) is at -105/110dBrA (left/right channels), or 0.0006/0.0003%. The third-order modulation products, at 17kHz and 20kHz, are higher at -85dBrA, or 0.006%.

**Intermodulation distortion FFT (18kHz + 19kHz summed stimulus, coaxial digital input, 16/44.1)**

Shown above is an FFT of the intermodulation distortion (IMD) products for an 18kHz + 19kHz summed sinewave stimulus tone measured at the output across an 8-ohm load at 10W for the digital coaxial input at 16/44.1. We find that the second-order modulation product (*i.e.*, the difference signal of 1kHz) is just above -100dBrA, or 0.001%. The third-order modulation products, at 17kHz and 20kHz, are at higher at -85dBrA, or 0.006%. Also visible are the IMD peaks from the 44.1kHz sample rate and the primary peaks at 25.1 and 26.1kHz.

**Intermodulation distortion FFT (18kHz + 19kHz summed stimulus, coaxial digital input, 24/96)**

Shown above is an FFT of the intermodulation distortion (IMD) products for an 18kHz + 19kHz summed sinewave stimulus tone measured at the output across an 8-ohm load at 10W for the digital coaxial input at 24/96. We find that the second-order modulation product (*i.e.*, the difference signal of 1kHz) is at -95dBrA, or 0.002%. The third-order modulation products, at 17kHz and 20kHz, are at higher at -85dBrA, or 0.006%.

**Intermodulation distortion FFT (18kHz + 19kHz summed stimulus, MM phono input)**

Shown above is an FFT of the intermodulation distortion (IMD) products for an 18kHz + 19kHz summed sinewave stimulus tone measured at the output across an 8-ohm load at 10W for the MM phono input. We find that the second-order modulation product (*i.e.*, the difference signal of 1kHz) is just above -80dBrA, or 0.01%. The third-order modulation products, at 17kHz and 20kHz, are at around -90dBrA, or 0.003%.

**Square-wave response (10kHz)**

Above is the 10kHz squarewave response using the analog line-level input, at roughly 10W into 8 ohms. Due to limitations inherent to the Audio Precision APx555 B Series analyzer, this graph should not be used to infer or extrapolate the R-N2000A’s slew-rate performance. Rather, it should be seen as a qualitative representation of the R-N2000A’s extended bandwidth. An ideal squarewave can be represented as the sum of a sinewave and an infinite series of its odd-order harmonics (*e.g.*, 10kHz + 30kHz + 50kHz + 70kHz . . .). A limited bandwidth will show only the sum of the lower-order harmonics, which may result in noticeable undershoot and/or overshoot, and softening of the edges. Here we can see a clean squarewave reproduction, with only very mild softening of the corners, and no overshoot.

**Damping factor vs. frequency (20Hz to 20kHz)**

The final graph above is the damping factor as a function of frequency. Both channels track closely, with a higher damping factor (around 280 to 300) between 20Hz and 2kHz. Above 2kHz, we see a decline in the damping factor, as low as 150 at 20kHz.

*Diego Estan*

Electronics Measurement Specialist