We've just received the Alctron MP73 X2 microphone preamplifier, and it's currently priced at only 3113 yuan after a discount at the official flagship store. Also it features dual channels. Both looking and sound quality are impressive. Let's take a closer look at this product. Many of you may notice its appearance right away: it almost identical to the Neve 1073? Yes, whether you call it a replica or a tribute, it is indeed designed with reference to the classic 1073 preamp.

Indeed, any product or component that includes "73" is undoubtedly paying homage to the classic Neve 1073, as it has become a standard in the industry. The Neve 1073 preamplifier borned in the 1970s and used to record countless classic albums over the decades. However, the real 1073 is quite expensive, and the older models are no longer available. Nowadays, a new AMS Neve 1073 single-channel unit costs around fifteen thousand, which is indeed too costly for most personal studios and hobbyists. Consequently, many replicas or devices designed with reference to the 1073 preamp have emerged on the market which is high quality with lower price.

Alctron is a brand under Aochuang Company, specializing in the research and development and production audio equipment. It has been a well-known brand in the domestic market. For a long time, especially in entry-level audio equipment such as microphones, preamps, and related accessories like pop filters, acoustic screen, microphone stands etc, Alctron's sales always been at the top, and it enjoys a very good reputation among users. It is particularly favored by personal music studios, internet celebrity singers, and live stream hosts.

In the high-end professional product, Alctron also has many products with excellent sound quality and performance that are comparable to foreign brands. Moreover, they consistently maintain their reputation for being cost-effective and offering great value for money. As a result, many professional music recording studios choose Alctron brand products. The MP73 X2 microphone preamp is actually designed for professional recording studios. Its 1U rack-mount design is specifically for easy mounting to rack. The packaging is exquisite which includes a detailed Chinese manual. Even friends who have never used such a preamp before can quickly get started by reading the manual.

The appearance of the MP73X2's panel has a vintage feel, especially the buttons and knobs, which essentially replicate the appearance of the Neve 1073. The panel is divided into two parts, each with identical function and independently responsible for one microphone. In fact, its internal structure is also completely duplicated, featuring two identical preamp circuits, effectively combining two preamps into one, but each operating independently. In other words, for the price of one preamp, you get two. This is why it is named "X2".

The interfaces on the back are also two independent sets on both sides. The metal housing is thick and depth of device is considerable, providing ample internal space which makes wiring more convenient. You may have noticed that its power supply interface is 24V, using an external power source, rather than having the power supply inside the chassis. In contrast, the original AMS NEVE1073 has an internal power supply. The advantage of an external power supply is that it can avoid electromagnetic interference from the built-in power supply. However, to achieve better sound quality with an internal power supply, higher requirements in terms of circuit design and shielding are necessary, which leads to higher costs.

The connectors of this preamp are not the multi-purpose Combined jacks, but rather separate independent connector for XLR and 6.5mm TRS jack, both gold-plated, giving a premium feel. We can choose our cables based on the devices we intend to connect. Since this preamp without coming with its own EQ or compression so it provides send and return ports for external effectors, allowing us to connect other effectors like EQ as needed.

The knobs and panel layout of MP73X2 preamp are similar to the 1073, but they only resemble the overall look, not a 100% replica. The gain knob for the preamp is dark red, identical in shape to the 1073, and features a step-wise design with audible clicks when switched, giving it a very retro feel. The knob has a total of 23 steps, with steps 1 to 14 ranging from +20 to +80 and steps 16 to 22 ranging from -10 to +20, for line input (LINE IN) gain adjustment, including an OFF position. This is the same as the Neve 1073, just with different positions for the knob's markings.

The blue knob with a range of 1-10 used to adjusted output level. It can combine left input gain to adjust the level. If the gain is higher, only a slight increase on this side is needed. For line input, the output can be slightly higher. The actual settings need to be adjusted based on the sound, which is also the difference between analog and digital devices.

The areas on both sides of device, including knobs and buttons as well as their functions, are exactly the same. The white rectangular buttons also closely resemble the style of the original 1073, with LEDs above them that light up when pressed. Personally, I find the circular power switch on the far right and the LED level meter a bit superfluous, as they don't quite match the retro simplicity of the 1073 style.

The functions of the buttons are as follows:

PHASE: Phase inversion. Pressing it will invert the phase by 180 degrees. For instance, when recording instruments like snare drums or guqins with two microphones placed one above and one below, the lower microphone can be reversed using this button. +48V: Phantom power switch

300/1200Ω: Impedance selection. Nowadays, the impedance of common condenser and dynamic microphones is around 300 ohms. However, the impedance of a preamp needs to be higher than that of the microphone, so typically 1200 ohms is used. If you use an impedance of 300 ohms, there will be a slight reduction in high frequencies, signal-to-noise ratio, and level. But this can also be a way to change the sound quality, so it's worth experimenting with sometimes.

INSERT: Line input switch. When pressed, the device switches to line input mode, which is useful for connecting instruments, etc.

Let me show you the disassembly diagram below.

Loosen the screws on the top and sides, you can remove the top cover. We can see that the entire housing is made of thick metal material, which can shield against interference. Additionally, you might have noticed that this preamp is split in the middle; the left and right parts are actually two identical main boards, with all components being exactly the same in both independent sets. Aside from the power cord and master switch being shared, everything else is duplicated. Essentially, it's like putting two preamps housed within a single casing.

The most important component of preamp is the input/output transformer, which also plays a crucial role in the sound quality. We can see that the transformer on the

MP73X2 has Alctron's own LOGO on it, indicating that this is a transformer developed and designed by Alctron themselves. The official statement states that it is completely based on the Carnhill transformer and the parameters are the same.

Some of you might know that the original AMS Neve 1073 uses transformers from Carnhill in the UK. Many foreign replica versions also directly purchase Carnhill transformers to ensure that sound is the same as 1073. However, Alctron's three transformers, especially when it comes to craftsmanship like the shielding casing, still have a significant gap compared to those imported from the UK. Of course, price and cost are the main reasons. But in terms of actual performance, they offer great value for money.

The 3055 power amplifier tube with a heat sink is the same model used in the original Neve 1073 preamp, and it's also a crucial component in the amplification circuit. It can be said that the design philosophy of this preamp's entire circuit remains consistent with the 1073.

The construction and craftsmanship behind the gain knob are different; in the original 1073, there are ribbon cables behind the knob, whereas Alctron's preamp uses a simpler mechanical structure. While the front knob caps look the same, the construction behind them is different.

Let's take a closer look at the details to understand the principle behind its gain stages.

Here are some additional detailed photos for reference. The red Vimar capacitors are "top-grade" components, and the materials used are quite substantial. The entire circuit is designed using traditional discrete components, without integrated circuits, making it purely analog.

Above is an overview of the appearance, functionality, and disassembly of this preamp for your reference. I've been using this preamp in my studio for a while, mainly combined with the Neumann U87 microphone. Here are my impressions:

1. The sound is clear and clean, without background noise or hiss, nor any harshness. It has a slightly warm tone that makes it great for recording vocals, indeed capturing that Neve-like style. However, compared to 1073, it certainly doesn't achieve the same level of smoothness, delicacy, and fullness.

2. Using the U87 microphone, setting the gain to around 9 or 10 o'clock is sufficient. It's very sensitive. It captures sound details well, but its sensitivity can also be a drawback when dealing with high sound pressure levels, as it tends to clip easily. In this regard, it's not as good as a tube preamp.

3. The dynamic performance and transient response are both excellent, making it quite suitable for recording vocals and string instruments.

Overall Review:

The Alctron MP73X2 is a pure analog entry-level microphone preamp that is highly suitable for personal music studios, small recording booths, as well as live streaming and performances. It delivers clear and clean sound with excellent dynamic range and minimal background noise. With up to 80dB of gain, it easily handles all common microphones, including ribbon mics. Compared to the built-in preamps in audio interfaces, the improvement in sound quality is quite noticeable. Its circuitry and some components are reference to Neve 1073 preamp, making it an affordable option. Priced around three thousand, it's worth noting that some replicas of the 1073 can cost over five thousand per piece or even eight to nine thousand. To put it simply, the sound quality from MP73X2 can rival products priced at around five thousand. Therefore, this product offers excellent value for money. If you're unsatisfied with the built-in preamp of your audio interface and want to purchase a pure analog standalone preamp that is rack-mountable, dual-channel, and prefers the look and sound style of the Neve 1073 but only has a budget of three thousand, then the Alctron MP73X2 is the best choice.