Tonewinner AD-2PRO+ Review: Heavy and Powerful Class A/AB Integrated Amp

I have great admiration for massive and powerful high-end amplifiers, especially when their size is not just for show. The Tonewinner AD-2PRO+ fits this description perfectly. Although it is a costly amplifier, it isn’t exorbitant - and it is truly thrilling. Stick with me till the end and you will understand why I feel this way.

Coming at around $2,700, greatly depending on when you find it, it promises a lot - but does it deliver?

Build Quality and Design

It makes a statement with its build quality. It’s got a solid, hefty feel thanks to the classic black and silver aluminum alloy chassis. The black finish feels smooth and looks great - it should easily complement most audio setups. Tonewinner prioritized durability here and you can feel it. It weighs almost 40 kg, or close to 80 pounds. I can stand on it comfortably without any harm - but please don’t try it.

On both sides of the amplifier there are large heatsinks that serve a purpose beyond just looking impressive. The large surface area of these heatsinks is designed to effectively handle high power output without overheating. This is particularly beneficial for those who enjoy extended listening sessions, as the device is less likely to shut down or become damaged due to overheating. Trust me, this is important - because the amplifier generates a significant amount of heat over time.

A remarkable design feature of this amp is its easy-to-read LED screen located on the front panel. The screen is capable of clearly displaying the current input of the amplifier, its volume, the mode in which it’s working, and the type of files it’s playing back, which is a pleasant addition.

Inputs and Outputs

The AD-2PRO+ is an integrated amplifier that offers a variety of input/output options.

Let’s start with the digital inputs, which go through the internal DACDigital-to-Analog Converter - a device that translates binary audio data into an analog electrical signal that can be amplified and heard.. There is one USB Type-B port to connect computers and some music streamers, along with two optical ToslinkAn optical S/PDIF digital audio interface using a plastic fibre and a red LED, common on TVs, soundbars, and consumer DACs. Limited to 24-bit/96kHz stereo PCM in practice; longer runs need glass fibre for stability. connectors and a single COAX RCA port.

Then we’ve got some analog options, that bypass the internal DAC and stay analog through the entire remainder of the audio chain. We can also connect the phono output of an MM or MC turntable. But most of you will probably use regular single-endedAn amplifier configuration using one output device for the complete audio waveform; produces even-order harmonic distortion considered "euphonic" by many. RCAs or balancedA signal transmission method using two opposite-polarity signal lines plus a ground; noise induced on both lines is cancelled at the differential input. XLRs for the left and right channels.

The power connector is separated by some space from everything else on the back to accommodate even the thickest audiophile-grade power cables. A useful addition is a ground connection, which can be connected to some kind of grounding unit to reduce noise or solve ground loopAn unwanted current path through the ground conductor between two devices, creating a 50/60Hz hum that's audible through the audio chain. Cured by galvanic isolation, ground lifts (carefully), or routing every device through a single grounded point. issues.

The speaker terminals are large and robust, and there are two sets of them. This allows you to connect two pairs of speakers, which can be useful for A/B testing. You can use a remote to switch between the outputs, or you can simply choose to bi-wire your speakers, setting the amplifier to use two sets of outputs at once.

If you want to use a subwoofer, you can connect it to this amplifier using dedicated sub outs - either RCA or XLRA professional locking audio connector with three pins: ground, positive signal, and negative signal; the standard for balanced studio connections..

Technical Specifications

The device has a signal-to-noise ratio (SNRSignal-to-Noise Ratio - the decibel gap between the maximum signal level and the noise floor; higher is better.) of over 100dB (A-weighted), which indicates a decent level of clarity in the sound. The frequency responseA graph showing output amplitude vs. frequency - the most fundamental measurement of any audio component's tonal character. range is wider than the standard 20Hz to 20kHz, with a range of 15Hz to 95kHz. It has a maximum power output of 240W when one channel is driven at 8 ohms.

Despite being rated at 8 ohms, the device can handle speakers with an impedanceThe total opposition (resistance + reactance) a speaker or headphone presents to the driving current, measured in ohms and varying with frequency. of less than 4 ohms without any issues. The total harmonic distortionDistortion products at integer multiples of the input frequency; even-order harmonics (2nd, 4th) are generally less audible than odd-order (3rd, 5th). of the unit is below 0.05% at 1kHz, which is not extremely low, but it applies to the entire unit, including the DAC and amp.

The USB input supports DSD512 and PCMPulse-Code Modulation - the standard digital audio format, encoding amplitude as binary integers at fixed time intervals (e.g., 16-bit/44.1kHz for CD). 32-bit up to 768kHz - that’s quite impressive. The optical and coaxial inputs go up to 192kHz, due to their nature.

Sound Quality

Tonality-wise, both Class AAn amplifier topology where the output transistors or tubes conduct current at all times, eliminating crossover distortion at the expense of significant heat and inefficiency. and Class A/B modes have a neutral sound, without any added bass or treble energy like some cheaper Class DA switching amplifier using pulse-width modulation to achieve 90%+ efficiency; modern Class D designs rival linear amplifiers in audio performance. amps.

It’s very dynamic, which can largely be attributed to the immense power it provides to the speakers and the headroomThe decibel margin between the loudest expected signal and an amplifier's clipping point. 10-20dB of headroom is generally needed for unclipped reproduction of dynamic recordings at realistic listening levels. it has in most cases. While the Class A/B mode offers higher headroom, making it slightly more dynamic, I still prefer Class A in most situations. Regardless of the mode, it produces a rich and full sound with a well-done midrangeThe frequency range from approximately 250Hz to 5kHz where most musical information, vocals, and instrument fundamentals reside. that brings out the vocals.

The separation of instruments is exceptional, which means that they are easily distinguishable and do not blend at all. Regarding the soundstageThe perceived three-dimensional acoustic space in a stereo recording - width beyond the speakers, depth front-to-back, and sometimes height information., this amplifier slightly widens it but sacrifices imagingThe ability to place individual instruments in precise, stable positions within the soundstage - good imaging means you can "point" to a violin in the mix. a little bit. The center image is sometimes fuzzy. That’s not a big issue in my opinion, but I know that some people prefer crystal-clear imaging with a dead center, that’s why I think it’s worth bringing up the fact that this amplifier focuses on soundstage width more.

In general, this amplifier provides a high-end audio experience with a refined sound that pairs well with a wide range of speakers. It is versatile and can handle both low and high impedance loads, and also allows for switching between Class A and Class A/B modes. The high power of the amplifier ensures consistent and powerful performance, no matter what it is connected to.