Every audio system requires amplification. In a traditional hi-fi set-up, the loudspeakers are always “passive”—which is to say, they don’t produce their own power. Instead, they must receive an amplified audio signal from an external source, aptly called an amplifier, in order to do their thing. Even in a more modern, self-contained audio system (like the Sonos Era 100, for example), the drivers that produce the sound must be amplified in order to function—this just all happens in a singular box rather than across hi-fi separates.

But if you’ve heard about amplifiers, you may have also heard about preamplifiers (often referred to as “preamps”) and wondered where they fit into an audio system, and whether you need one. Let’s answer those questions, shall we?

What Does a Preamp Do?

An audio signal needs plenty of attention before it’s ready to be amplified—so ultimately the question “what does a preamp do?” broadly contains its own answer. A preamplifier takes care of everything that needs to be done before the audio signal (sent from the music source) is amplified and sent onwards to the system’s speakers.

In a self-contained audio system like the Sonos speaker, the preamplifier and the amplifier are in the same enclosure, along with the speaker drivers that actually deliver the sound. Even in a more sophisticated hi-fi separates setup, the preamplifier part of proceedings is still often handled out of sight, within the amplifier. These types of amps are known as “integrated amplifiers” and contain both preamp and amplifier functionality.

However, some people prefer to separate out this functionality, which is when you may come across a preamplifier as its own piece of equipment, paired with a power amplifier. In these cases, the preamplifier allows you to select the source of music you’d like to hear (the majority have a selection of input options in order to support a system with multiple sources), and also set and adjust the volume.

The preamp also ensures the audio signal is at “line level”—that is, the standard voltage strength of an audio signal transmitted between components—and sends it on to be amplified, ready to be moved onwards, finally, to the speakers.

Does an External Preamp Improve Sound Quality?

Hi-fi orthodoxy says that individual functions in any system should be kept as separate as possible if the best results are to be achieved. The thinking goes that, by keeping electrical activity as shielded and self-contained as possible, the audio signal has the best shot at remaining as pure and uncolored as possible.

By dividing the preamplifier and the amplifier functions into separate boxes, there should be a reduction in electrical noise and interference around the signal compared to having it all crammed into a single box.

There is what looks like another maddening design fail, with the Switch’s left shoulder buttons, L and ZL, positioned on the right of the Mini Arcade Pro’s eight-button layout, with the right-hand R and ZR buttons to their left. However, this is actually a trick borrowed from other console arcade sticks, and it works surprisingly well for 2D fighters such as Ultra Street Fighter II. Capcom’s classic series builds combos from light, medium, and heavy punches and kicks, which is best suited to a six-button layout. Played on a ‘regular’ controller, those inputs usually extend from the four face buttons to the right-hand shoulder buttons. Here, the B, A, and ZR buttons, and the Y, X, and R buttons line up in rows, so the game plays just like it would on an actual cabinet. It’s neat.

However, I wouldn’t use the Mini Arcade Pro to play fighters competitively, even for low-stakes online play. While the joystick feels great, the rest of the inputs feel far from tournament grade. I occasionally noticed overly sensitive “twitchy” controls, where pressing a button once—to select a game in a compendium title, for instance—would result in multiple inputs, even without that aforementioned Turbo feature activated. It’s not a consistent problem, but annoying when it happens.

As the Mini Arcade Pro is only designed for one player, it feels better suited to arcade puzzlers, shooters, and side-scrolling beat-’em-ups anyway. The Golden Axe games in Sega Genesis/Mega Drive Collection, the entire roster of Capcom Beat-’Em-Up Bundle, and Namco Museum’s Splatterhouse all fared well, as did classics Pac-Man and Galaga. Shooters in particular are where that Turbo feature does come in handy—hold down the Turbo button, then the input you want to apply the feature to, and blast away to your heart’s content. Repeat the process to turn the feature off.

That’s probably not enough to salvage this for most players, though. Unless you’re using your Switch or Switch 2 to near-exclusively play old-school games—or at least old-school style games, like Streets of Rage 4 or Terminator 2D: No Fate—then this has limited appeal. Coupled with the hoops you need to jump through to update it for Switch 2 usage and the abysmal imagery slopped all over the thing, the Mini Arcade Pro isn’t so much retro as it’s better left in the past.

In the first part of our round-up of the Dallas meeting of the Innovative Optical and Wireless Network (IOWN) project’s Global Forum conference in October 2025, we looked at the technological development of the association’s all-photonics network (APN) – and the continued work in essentially “moving from electronics to photons”, as a representative of one of its key member companies insisted its mission boils down to.

One of the most important developments over the past year was using the APN to support a theatre performance that synchronised live and virtual performers in Japan and Taiwan, running over a network that was over 3,000km long.

In addition to validating a very important use case, the Cho Kabuki project also saw the APN being at the heart of a digital twin, whereby the producers could digitise the performance character and manipulate it in the computing space while being certain that latency would not adversely affect synchronisation. The lessons from this area are likely to be applied to digital twins in the industrial space. Smart warehouses are one key example cited.

NTT’s Masahisa Kawashima, IOWN technology director and head of the technology working group at the IOWN Global Forum, says plans also include demonstrating commercial operability of the APN and defining a new functional architecture for artificial intelligence (AI) computing platforms using co-packaged optics and optical circuit switches.

The agile deployment of optical fibres is seen as essential for forthcoming 6G networks. IOWN APN provides a virtualisation layer on top of physical fibre infrastructure. This allows multiple mobile operators to share fibre infrastructure, mitigating availability issues and costs.

It is worth noting that soon after the Dallas conference, IOWN forum member Nokia announced a strategic partnership with Nvidia to add the latter’s AI-powered radio access network (RAN) products to Nokia’s RAN portfolio, enabling communications service providers to launch AI-native 5G Advanced and 6G networks on Nvidia platforms.