Differences between digital power amplifier and switching power amplifier in driving subwoofer

In the field of audio, digital power amplifiers and switching power amplifiers show obvious differences when driving subwoofers. While they have similar power, digital amps tend not to be able to push the subwoofer as effectively as switching power amps can.

Take Sinbosen D4-2000 (4 x 2000w into 8 Ohms, 3400w into 4 Ohms, 4 x 4760w into 2 Ohms) and FP20000Q (4 x 2200 Watts into 8 Ohms, 4 x 4000 Watts into 4 Ohms) as an example. Can the D4-2000 be used for a subwoofer? The answer is no. Because this will cause the risk of burning out the power amplifier board and speaker speakers, causing unnecessary losses. The FP20000 is a switching power amplifier that can be used for subwoofers. If you prefer digital power amplifiers, we recommend D4-3000 and D2-4200, both of which can be used for subwoofers, bringing powerful bass effects.

First of all, digital power amplifiers require extremely high PWM frequencies when amplifying low-frequency signals. Since the subwoofer needs to process low-frequency signals, and the PWM frequency of the digital power amplifier is usually high, this leads to difficulties in processing low-frequency signals. The higher PWM frequency limits the processing precision and accuracy of the digital power amplifier for low-frequency signals, thus affecting the driving effect of the subwoofer.

Secondly, the output filter of the digital power amplifier is designed to filter out high-frequency noise and harmonic components, while the subwoofer needs to transmit low-frequency signals.   As a result, the characteristics of the output filter may not pass low-frequency components well, thereby affecting the effect of the subwoofer.

In contrast, switching power amplifiers use traditional linear amplification techniques. It works by amplifying low-frequency signals and transferring power to the subwoofer through an output transformer. Switching power amplifiers feature wide bandwidth and high dynamic range, ideal for driving subwoofers. Switching power amplifiers are usually equipped with an output transformer to isolate and match the impedance between the amplifier and the subwoofer. This helps provide better power delivery and matching, allowing the switching power amplifier to drive the subwoofer more efficiently.

To sum up, under the same power, there are obvious differences in driving the subwoofer between digital power amplifiers and switching power amplifiers. Digital power amplifiers are limited by PWM frequency and output filters, and are not suitable for effectively driving subwoofers, while switching power amplifiers use linear amplification principles and output transformers, which are excellent in processing low-frequency signals and driving subwoofers. Therefore, in order to obtain a better bass effect, it is very important to choose a suitable power amplifier.