Burmester 232 Integrated Amplifier Measurements

Link: reviewed by Phil Gold on SoundStage! Ultra on February 15, 2026

General Information

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

The Burmester 232 was conditioned for 1 hour at 1/8th full rated power (~12W 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 232 under test came equipped with the optional digital module and offers two sets of line-level analog inputs (both XLR), three digital inputs (RCA, optical, XLR), left/right pre-outs (XLR), one set of speaker level outputs, and one headphone output over 1/4” TRS connector. Streaming options are also offered. For the purposes of these measurements, the following inputs were evaluated: digital coaxial (RCA), analog (XLR), as well as the headphone output.

Most measurements were made with a 4Vrms line-level analog input and 0dBFS digital input. The signal-to-noise ratio (SNR) measurements were made with the default input signal values but with the volume set to achieve the maximum (1% THD) output power of 90W into 8 ohms. For comparison, on the line-level input, a SNR measurement was also made with the volume at maximum.

Based on the accuracy and randomness of the left/right volume channel matching (see table below), the 232 volume control is digitally controlled but operating in the analog domain. The 232 overall volume range is from -57dB to +23dB (line-level input, speaker output). It offers 0.5 to 3dB increments over 60 steps.

Our typical input bandwidth filter setting of 10Hz-22.4kHz was used for all measurements except FFTs and THD versus frequency, where a bandwidth of 10Hz-90kHz was used. Frequency response measurements utilize a DC to 1 MHz input bandwidth.

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

Published specifications vs. our primary measurements

The table below summarizes the measurements published by Burmester for the A232 compared directly against our own. The published specifications are sourced from Burmester’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 to 1MHz, assume, unless otherwise stated, 10W into 8 ohms and a measurement input bandwidth of 10Hz to 22.4kHz, and the worst-case measured result between the left and right channels.

Our primary measurements revealed the following using the line-level analog input and digital coaxial input (unless specified, assume a 1kHz sinewave at 4Vrms or 0dBFS, 10W output, 8-ohm loading, 10Hz to 22.4kHz bandwidth):

For the continuous dynamic power test, the 232 was able to sustain 162W into 4 ohms (~3% THD) using an 80Hz tone for 500ms, alternating with a signal at -10dB of the peak (16.2W) for 5 seconds, for 5 minutes without inducing any fault protection. This test is meant to simulate sporadic dynamic bass peaks in music and movies. During the test, the sides of the 232 were only slightly warm to the touch.

Our primary measurements revealed the following using the analog input at the headphone output (unless specified, assume a 1kHz sinewave, 4Vrms input/2Vrms output, 300 ohms loading, 10Hz to 22.4kHz bandwidth):

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

In our frequency response plots above (relative to 1kHz), measured across the speaker outputs at 10W into 8 ohms, the 232 is essentially perfectly flat within the audioband (20Hz/20kHz, 0/-0.1dB). The -3dB point is at roughly 130kHz, and 0dB at 5Hz. The 232 appears to be DC-coupled. 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 sub-out (8-ohm loading, line-level input)

Above is the frequency response plot (relative to 20Hz) of the line-level sub-out, measured up to 80kHz. We find the same response as the speaker-level outputs and no low-pass filter applied.

Phase response (8-ohm loading, line-level input)

Above are the phase-response plots from 20Hz to 20kHz for the line-level input, measured across the speaker outputs at 10W into 8 ohms. The 232 appears to invert polarity (-180 degrees of phase shift); however, this is likely due to an XLR pin-out assignment that is different from the convention used by the audio analyzer. Ignoring the phase inversion, the 232 yielded only -20 degrees of phase shift at 20kHz.

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

The chart above shows the 232’s frequency response (relative to 1kHz) as a function of input type measured across the speaker outputs at 10W into 8 ohms. The two green traces are the same analog input data from the speaker-level frequency-response graph above, but limited to 80kHz. The blue and red traces are for a 16-bit/44.1kHz dithered digital input signal from 5Hz to 22kHz using the coaxial input, the purple and green traces are for a 24/96 dithered digital input signal from 5Hz to 48kHz, and the pink and orange traces are for a 24/192 dithered digital input signal. At low frequencies, the digital signals yielded a flat response down to 5Hz, same as the analog response. The -3dB points are: just past 20kHz for the 16/44.1 data, 46kHz for the 24/96, just shy of 90kHz for the 24/192 data, and 130kHz for the analog input. Also of note, the digital plots showed brick-wall-type filtering around half the sampling frequencies, as well as rippling (+/-0.2dB) in the response at high frequencies.

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-outputs of the 232, where 0dBFS was set to yield 2Vrms. 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. The 24/96 data were at 0dB at -120dBFS, while the 16/44.1 data were +2/0dB at -120dBFS. We extended the sweep to -140dBFS . . .

…where we found the 24/96 plot only overshot by +2/+4dB at -140dBFS. An excellent result.

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 line-level pre-outs of 232. The impulse shows an inverted response; however, this is likely due to an XLR pin-out assignment that is different from the convention used by the audio analyzer. Ignoring the phase inversion, the 232 appears to implement a typical symmetrical sinc function 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-outputs of the 232 where 0dBFS is set to 2Vrms. J-Test was developed by Julian Dunn 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.

Here we see a strong J-Test result, with only two small spurious peaks in the audioband at -150dBFS. This is an indication that the 232 DAC should have strong jitter immunity.

J-Test (optical)

The chart above shows the results of the J-Test test for the optical digital input measured at the line-level pre-outputs of the 232. The optical input yielded essentially the same results compared to the coaxial input.

J-Test (AES-EBU)

The chart above shows the results of the J-Test test for the AES-EBU XLR digital input measured at the line-level pre-outputs of the 232. We see essentially the same results compared to the coaxial input.

J-Test (coaxial, 10ns jitter)

The chart above shows the results of the J-Test test for the coaxial digital input measured at the line-level output of the 232, with an additional 10ns of 2kHz sinewave jitter injected by the APx555. The telltale peaks at 10kHz and 12kHz cannot be seen. The optical and AES-EBU showed the same results.

J-Test (coaxial, 100ns jitter)

The chart above shows the results of the J-Test test for the coaxial digital input measured at the line-level output of the 232, with an additional 100ns of 2kHz sinewave jitter injected by the APx555. This time the telltale peaks at 10kHz and 12kHz can be seen, but only at a very low -135dBFS. The optical and AES-EBU inputs yielded the same results. Another indication of strong jitter immunity.

Wideband FFT spectrum of white noise and 19.1kHz sine-wave tone (coaxial input)

The chart above shows a fast Fourier transform (FFT) of the 232’s line-level pre-outputs with white noise at -4dBFS (blue/red) and a 19.1 kHz sinewave at 0dBFS fed to the coaxial digital input, sampled at 16/44.1. The steep roll-off around 20kHz in the white-noise spectrum shows the implementation of a filter of the brick-wall-type variety. There are no low-level aliased image peaks within the audioband above the -135dBrA noise floor. The primary aliasing signal at 25kHz is highly suppressed at -100dBrA, while the second and third distortion harmonics (38.2, 57.3kHz) of the 19.1kHz tone are near the same level.

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

The chart above shows RMS level (relative to 0dBrA, which is 1W into 8 ohms or 2.83Vrms) as a function of frequency, for the analog line-level input swept from 5Hz to 50kHz. 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 see that the deviations between no load and 4 ohms are extremely small at roughly 0.01dB. This is a strong result and an indication of an extraordinarily low output impedance, or extremely high damping factor. With a real speaker load, deviations measured lower at roughly 0.006dB.

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

The chart above shows THD ratios at the speaker-level outputs 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 the left and right channel at 1W output into 8 ohms, purple/green at 10W, and pink/orange at 84W. The power was varied using the 232 volume control. The 1W THD ratios were the lowest (the 10W data were very close, within 2-3dB), ranging from 0.0015% from 20Hz to 200Hz, then a steady climb to 0.04% at 20kHz. At 84W, THD ratios were fairly flat across the sweep at 0.2-0.3%.

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

The chart above shows THD ratios measured at the speaker-level outputs of the 232 as a function of output power for the analog line-level input for an 8-ohm load (blue/red for left/right) and a 4-ohm load (purple/green for left/right), with the volume set to maximum. The 8-ohm THD data is relatively constant at 0.002-0.003% from 50mW to the “knee” at just past 70W.  The 4-ohm THD data is also relatively constant at 0.005-0.006% from 50mW to the “knee” at roughly 130W. The 1% THD marks were hit at 90W and 150W into 8 and 4 ohms.

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

The chart above shows THD+N ratios measured at the speaker-level outputs of the 232 as a function of output power for the analog line level-input, for an 8-ohm load (blue/red for left/right) and a 4-ohm load (purple/green for left/right) with the volume set to maximum. The 8-ohm THD+N data ranges from 0.01% at 50mW down to between 0.002- 0.003% from 2W to the “knee” at just past 70W.  The 4-ohm THD+N data ranges from 0.02% at 50mW down to between 0.005- 0.006% from 2W to the “knee” at just roughly 130W.

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 232 as a function of frequency into three different loads (8/4/2 ohms) for a constant input voltage that yields 20W at the output into 8 ohms (and roughly 40W into 4 ohms, and 80W 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 a roughly 5dB increase in THD from 8 to 4 to 2 ohms from 400Hz to 20kHz. At lower frequencies, the difference was smaller at 2-3dB. Even into 2 ohms, THD ratios ranged from 0.003% at 20Hz, climbing to 0.2% at 20kHz. A strong result, due to the 232’s robust power supply and exceedingly low output impedance.

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 232 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). Generally, THD ratios into the real speakers were similar if not lower than those measured across the resistive dummy load. The largest differences were seen with the two-way speaker, which yielded THD ratios of 0.008% at 20Hz versus 0.0015% for the resistive load and three-way speaker, and 0.001% from 400Hz to 1kHz versus 0.002-0.003% for the resistive load and 3-way speaker. The 3-way speaker yielded the highest THD ratio at 20kHz, 0.06% versus 0.05% for the resistive load and 0.03% for the 2-way speaker. This is a very strong result, and once again, likely due to the 232’s robust power supply and exceedingly low output impedance.

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 232 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 was 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). We find that all three IMD traces are very close to one another, ranging from 0.0015% to 0.005%.

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 232 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 was 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). At high frequencies, all three results are essentially identical at 0.002% from 500Hz to 1kHz. From 40Hz to 500Hz, the 3-way speaker yielded the highest IMD results at just under 0.02%, with the 2-way speaker at just under 0.01%, and the resistive load at 0.006%.

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 even (2/4/6/8kHz/etc.) harmonics dominate with the peak at 2kHz at -90dBrA, or 0.003%, and subsequent peaks below -100dBrA, or 0.001%. The odd signal harmonics (3/5/7/9kHz/etc) can be seen at -110dBrA, or 0.0003%, and below. On the right side of the signal peak, we find power-supply-related noise peaks, with the second harmonic (120Hz) dominating at -115dBrA, or 0.0002%. Other noise peaks can be seen at and below the -120dBrA level.

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. Both the signal harmonics and power-supply related noise peaks are very similar in amplitude to the analog FFT above.

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. We see essentially the same result as with the 16/44.1 FFT above, but with a lower noise floor due to the increased 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, with no signal harmonics above the -135dBrA noise floor, and power-supply-related noise peaks at -130dBrA, or 0.00003%.

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, with no obvious signal harmonics above the -145dBrA noise floor, and power-supply-related noise peaks at -130dBrA, or 0.00003%, down to -140dBrA, or 0.00001%.

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. The most predominant (non-signal) peak is the second (100Hz) signal harmonic at a low -95dBrA, or 0.002%. Other peaks (both signal harmonics and power-supply noise related harmonics) can be seen at -110dBrA, or 0.0003, and below.

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 -100dBrA, or 0.001%, while the third-order modulation products, at 17kHz and 20kHz are just below the -105dBrA, or 0.0006%, level.

Intermodulation distortion FFT (line-level input, APx 32 tone)

Shown above is the FFT of the speaker-level output of the 232 with the APx 32-tone signal applied to the analog input. The combined amplitude of the 32 tones is the 0dBrA reference, and corresponds to 10W into 8 ohms. The intermodulation products—i.e., the “grass” between the test tones—are distortion products from the amplifier and are at and below the -110dBrA, or 0.0003%, level.

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 (-1dBFS). We find that the second-order modulation product (i.e., the difference signal of 1kHz) is at -100dBrA, or 0.001%, while the third-order modulation products, at 17kHz and 20kHz, are just below the -105dBrA, or 0.0006%, level.

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 (-1dBFS). We find that the second-order modulation product (i.e., the difference signal of 1kHz) is at -100dBrA, or 0.001%, while the third-order modulation products, at 17kHz and 20kHz, are just below the -105dBrA, or 0.0006%, level.

Squarewave 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 232’s slew-rate performance. Rather, it should be seen as a qualitative representation of the 232’s mid-to-high 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. In this case, we find relatively clean corners, with some softening but no overshoot.

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

The final graph above is the damping factor as a function of frequency. We can see here a constant damping factor just under 1800 from 20Hz to 2kHz, then down to just under 1000 at 20kHz. This is an exceptional result for a medium-powered solid-state integrated amplifier.

Diego Estan
Electronics Measurement Specialist