This is a review and detailed measurements of the B&K Components AV30.2 Power Amplifier. It is on kind loan from a member. The AV30.2 is discontinued but is available on the used market for low price I am told. I found one listing with asking price of $175 but not others. The good news is that it uses the ICEPOWER 50ASX2SE class-D amplifier module so the review should be relevant to other amplifiers in the market now.
The B&K amp is targeted the CI (custom integration) market meaning it is usually installed in home and businesses by a dealer/installer as part of a larger system. This amp for example could be hidden behind a flat panel TV powering a couple of speakers. For this reason, the form-factor and connectivity follows the requirements for this market.
Here is the front panel:
The "business end" is on the back:
As you can tell, there is fair amount of connectivity for home automation. I did not investigate them but I imagine you can power the unit on and off remotely to say, synchronise with the TV being turned on/off.
I liked the level control for both channels. It is buttery smooth, putting many other volume controls to shame. Using that, I was able to get perfect match between the two channels -- something you can't hardly do with any modern amplifier anymore.
The speaker connections use phoenix connectors which while super common in CI industry, was not the greatest choice here. It was very easy to have the outputs short out if you left any copper sticking out the screw terminal. In use, the connector did not make tight enough connection causing the performance of one channel to vary as much as 20 dB. It was tight by feel but noise level would go up and down if I wiggled it. For intended application probably did not matter. If you want to use it for hifi home application, you may want to hard wire them if you run into the same issue I did.
In use, the unit barely got warm to touch. There is plenty of ventilation on top and bottom which helps in this regard as does the high efficiency of its switchmode power supply and class-d amplification module.
Power Amplifier Audio Measurements
Here is our usual dashboard at 5 watt into 4 ohm:
I adjusted the output gain to 29 dB which means the controls were near max. Performance may vary some at lower gain values. I used 29 dB since it is probably the most common/THX recommended gain level.
THD+N was 0.008%. The 50ASX2SE spec from what I recall is less than half at 0.003%. The discrepancy may be due to gain stage, the connector and just variation in units. Overall, it is in the ballpark of what they advertise. This translates into a SINAD above mid-point of all the amplifiers we have tested:
Signal to noise ratio is just good enough for 16-bit audio playback at 98 dB at full power:
On right is the same measurement but relative to max of 5 watts. SNR does not drop much which is very good.
Frequency response was dead flat in audible band and quite well-behaved with output filtering:
Wide-band FFT spectrum shows ugliness that we typically see in class-d amps (at 5 watt here) and this is probably a more uglier than the normal picture:
More of a visual scare though than audio.
Most important measurement for an amplifier is power versus distortion and noise. Let's start with the common load of 4 ohm:
As you see, one channel started to deviate as I said in the introduction. But still, both of them are smooth and well-behaved giving us a power rating of 42 watts before hard clipping sets in.
At 8 ohm, power level drops a lot as you would expect:
Funny there though in how much lower noise and distortion the AV30.2 has compared to the NAD T758 AV Receiver (in dashed blue). Would be a good replacement for it had it had more power. If the modules higher in range have same performance, they may be a good application to power home theaters.
That said, these modules have almost no headroom as their peak power is almost the same as average:
This is because unlike class AB amplifiers, the power supply in these class-D amps is regulated and so other than some storage in output caps, can't provide more juice for short periods.
Another sign of good design is how the performance of the amplifier varies with level and frequency:
Each line pair of the same color (solid and dashed) is at a different frequency. An ideal amplifier would not care about frequency so all the graphs would land on top of each other. Here, they vary some but much less than some other amplifiers I have measured.
Conclusions
The B&K AV30.2 provides competent performance across suite of measurements. It runs cool, is efficient and small. It easily outperforms mass market AVRs for example. Alas, there is not a lot of power here so other than desktop speaker application, I would seek out something more powerful.
Overall, I am going to put the B&K AV30.2 and by implication, the ICEPOWER 50ASX2SE on my recommended list for mid-level performance amplification.
------------
As always, questions, comments, recommendations, etc. are welcome.
The demands by the Pink Panthers seems to never end. The one I use in this review wants to have "plastic" surgery done to repair his ear. I tell him that nobody notices that but he says he does every time he looks in the mirror. Please donate some money for his surgery using: https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/
The B&K amp is targeted the CI (custom integration) market meaning it is usually installed in home and businesses by a dealer/installer as part of a larger system. This amp for example could be hidden behind a flat panel TV powering a couple of speakers. For this reason, the form-factor and connectivity follows the requirements for this market.
Here is the front panel:
The "business end" is on the back:
As you can tell, there is fair amount of connectivity for home automation. I did not investigate them but I imagine you can power the unit on and off remotely to say, synchronise with the TV being turned on/off.
I liked the level control for both channels. It is buttery smooth, putting many other volume controls to shame. Using that, I was able to get perfect match between the two channels -- something you can't hardly do with any modern amplifier anymore.
The speaker connections use phoenix connectors which while super common in CI industry, was not the greatest choice here. It was very easy to have the outputs short out if you left any copper sticking out the screw terminal. In use, the connector did not make tight enough connection causing the performance of one channel to vary as much as 20 dB. It was tight by feel but noise level would go up and down if I wiggled it. For intended application probably did not matter. If you want to use it for hifi home application, you may want to hard wire them if you run into the same issue I did.
In use, the unit barely got warm to touch. There is plenty of ventilation on top and bottom which helps in this regard as does the high efficiency of its switchmode power supply and class-d amplification module.
Power Amplifier Audio Measurements
Here is our usual dashboard at 5 watt into 4 ohm:
I adjusted the output gain to 29 dB which means the controls were near max. Performance may vary some at lower gain values. I used 29 dB since it is probably the most common/THX recommended gain level.
THD+N was 0.008%. The 50ASX2SE spec from what I recall is less than half at 0.003%. The discrepancy may be due to gain stage, the connector and just variation in units. Overall, it is in the ballpark of what they advertise. This translates into a SINAD above mid-point of all the amplifiers we have tested:
Signal to noise ratio is just good enough for 16-bit audio playback at 98 dB at full power:
On right is the same measurement but relative to max of 5 watts. SNR does not drop much which is very good.
Frequency response was dead flat in audible band and quite well-behaved with output filtering:
Wide-band FFT spectrum shows ugliness that we typically see in class-d amps (at 5 watt here) and this is probably a more uglier than the normal picture:
More of a visual scare though than audio.
Most important measurement for an amplifier is power versus distortion and noise. Let's start with the common load of 4 ohm:
As you see, one channel started to deviate as I said in the introduction. But still, both of them are smooth and well-behaved giving us a power rating of 42 watts before hard clipping sets in.
At 8 ohm, power level drops a lot as you would expect:
Funny there though in how much lower noise and distortion the AV30.2 has compared to the NAD T758 AV Receiver (in dashed blue). Would be a good replacement for it had it had more power. If the modules higher in range have same performance, they may be a good application to power home theaters.
That said, these modules have almost no headroom as their peak power is almost the same as average:
This is because unlike class AB amplifiers, the power supply in these class-D amps is regulated and so other than some storage in output caps, can't provide more juice for short periods.
Another sign of good design is how the performance of the amplifier varies with level and frequency:
Each line pair of the same color (solid and dashed) is at a different frequency. An ideal amplifier would not care about frequency so all the graphs would land on top of each other. Here, they vary some but much less than some other amplifiers I have measured.
Conclusions
The B&K AV30.2 provides competent performance across suite of measurements. It runs cool, is efficient and small. It easily outperforms mass market AVRs for example. Alas, there is not a lot of power here so other than desktop speaker application, I would seek out something more powerful.
Overall, I am going to put the B&K AV30.2 and by implication, the ICEPOWER 50ASX2SE on my recommended list for mid-level performance amplification.
------------
As always, questions, comments, recommendations, etc. are welcome.
The demands by the Pink Panthers seems to never end. The one I use in this review wants to have "plastic" surgery done to repair his ear. I tell him that nobody notices that but he says he does every time he looks in the mirror. Please donate some money for his surgery using: https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/