TEST: Focusrite ISA 428 MKII

A trademark like thunder, at least when it comes to producers of my decade. While the ambitious new generation knows the company Focusrite mostly from the interface home recording area, users of my age cringe with awe at the mere mention of the Red or Blue Series. With the Focusrite ISA 428 MKII, the traditional company is now trying to save the flair of great productions of bygone days into the present.

Big names, big budgets!

Why this fuss about the name Focusrite? Well, the company was founded in 1985 by probably the biggest name in console history, Rupert Neve, who sold the company just a few years later. Nevertheless, the comparatively short time was enough to create the first legends, including the ISA 110 channel strip, which was designed specifically for George Martin at the time. Not without reason, many visual details show some parallels to the Focusrite ISA 428 MKII under review, as the preamp circuit is based on the AIR Studios classic.

The construction of the Focusrite ISA 428 MKII

In keeping with a true preamp, Focusrite does not use next-level components such as heavily intervening filters or compressors. Instead, 4 identical channel strips are used, whose only task is to catch up with the supplied voltage. At the same time, the Focusrite ISA 428 MKII is very flexible in terms of input level, so it can handle a microphone level via XLR, line via TRS or high-impedance material via jack with the appropriate inputs. Each channel has its own balanced loop-in path so that external processors can be brought on board. The loop-in path can be activated via a push button on the front panel, which increases the ease of use by quite a bit. Anyone who has ever crawled around lying on the floor behind their Outgear Rack with a flashlight to wire up their processors knows what I mean.

Actually, it's a mistake to speak of a 4-channel preamp, as the Focusrite ISA 428 MKII calls 4 more digital inputs its own, which are fed via XLR jacks. On the front panel you can set the appropriate bitrate from 44.1 up to 192 kHz, and the unit can also output word clock. Still, the Focusrite ISA 428 MKII is primarily designed for project studio work, where you rarely record more than 4 channels at a time.

The linchpin of the Focusrite ISA 428 MKII is the channel's respective gain control, which offers up to 60 dB of gain via a triple selector switch (0 - 30 dB) and a toggle switch (40 - 60 dB). The fine adjustment is then taken over by an infinitely variable trim control, which offers another 20 dB of pre-amplification if necessary, so that a maximum signal amplification of up to 80 dB is possible. This also makes it possible to work with very low-power ribbon microphones. For line and Hz signals, of course, such values do not make sense, so for line signals the gain range was set from -20 dB to +10 dB, for Hz signals from +10 dB to +40 dB.

As a high-pass filter, each channel has a stepless low-cut filter that can be tuned from 16 Hz to 420 Hz and has a very steep slope of 18 dB/oct. Such a hard cut seems to be very helpful for eliminating rumble noises, but for processing a proximity effect the filter might interfere too much. Switchable 48V phantom power and phase inversion round off the overall impression. On the right outside there are a total of 8 pcs. 6-digit LED chains, which show the output level.

The impedance selection of the Focusrite ISA 428 MKII

It should not be a secret anymore that the sound of certain microphone types changes according to the impedance of the preamp. Still, I'm always surprised at how many engineers and producers haven't heard about these sonic possibilities. However, this could quickly change with the Focusrite ISA 428 MKII, as special attention has been paid to this circuit trick.

As many as 4 different impedances can be set on the microphone input of the Focusrite ISA 428 MKII via the push-button selection on the front of the panel. The choices are Low (600 ohms), Medium (2,400 ohms), High (6,800 ohms), and in keeping with the product's progenitor, the ISA 110 input impedance of 1,400 ohms. To what extent the ohm selection affects the sound, the practical test will show.

The Focusrite ISA 428 MKII in Practice

I admit that at the beginning of the test I was hoping for a certain basic sound from the Focusrite ISA 428 MKII. For a dinosaur like me, who as a consequence of his birth decade was allowed to experience his sonic imprint in the studio heyday of the eighties, resonates with certain products still a touch of hope, it may have been saved a little sound culture over into the "present time" and not again with the "now-yet-cheaper" flag everything down bludgeoned, which may still have remained claim.

Already at the first signals that resound from the preamp, a satisfied smile settles on my lips. Not that the lush sound of the eighties is resurrected at the push of a button, but the neutral and transparent resolution of the Lundahl transformers create a clearly structured basis, which offers a direct enhancement to any signal.

At the same time, the Focusrite ISA 428 MKII has this difficult to describe, British-decent coloring, which was inherent in many products of the eighties, far from the often somewhat sultry soft USA sound. Before the loudness mastering mania of the nineties started to nip every sonic detail in the bud, the individual components in the signal path were clearly more responsible for what ended up on the turntable as the final result. The contour-rich sound of the Focusrite ISA 428 MKII offers an excellent basis for many different styles, as long as you are not looking for a strongly saturated vintage sound. For this orientation, the basic sound of the product is clearly too clear and too finely resolved.

The previously mentioned input impedance selection brings many unexpected sound impressions in practice, whereby the final result depends strongly on the type of microphone used. Thus, I could detect the strongest coloration with the comparatively simple classics from the dynamic range. A Shure SM57 or an AKG D320 sounded surprisingly soft in the low variant, while other microphones such as the R2 MKII ribbon microphone from Golden Age Project reacted very little to the different impedances.

If you want to pay homage to the ISA 110 sound, you can of course generally work with the 1,400 Ohm setting, which also delivers consistently good results, but you are depriving yourself of some sound enhancements that you might not have expected from the Focusrite ISA 428 MKII in this way. Of course, the basic sound of the respective microphone remains, but the colorations expand the sound spectrum in interesting directions. Here is simply trial and error, a core statement in the sense of "if this than that" does not exist.

With a gain of up to 80 dB, the Focusrite ISA 428 MKII can indeed cope with all microphone types, and the input noise is very low at -126 dB-A. Even at maximum level, no really annoying input noise could be perceived, especially since this would only be noticed in very quiet passages. Nothing against low-noise preamps, but what you sometimes have to read as a criterion has partly nothing to do with practice.

The line inputs as well as the high-impedance Hz inputs were also convincing across the board. The open and robust basic sound lets everything that has to be processed in high-level signals or, conversely, in high-impedance signals, appear in a very good image. Whether it was just an electric bass, an acoustic guitar with pickup or an electric piano, the sound is always clear, resistant to overdriving and covered with a very fine resolution, which supports and strengthens the respective basic sound of the instrument.

Finally, a tip for electric guitarists. Even if it is still touted here and there, a first to take electric guitar sound is never generated via a Hz input with amp / speaker simulators. Even the best Hz input cannot hide the fact that at least 50% of a high-quality electric guitar sound is generated by a real amplifier with a real speaker and a real microphone. Without this signal chain you can record a demo at most, nothing more!

Conclusion

With the Focusrite ISA 428 MKII, one of the biggest names of the eighties offers a very valuable preamp for the project studio. The four-channel preamp turns out to be an excellent-sounding input stage for almost all signals that arise, and with up to 80 dB of gain it knows how to handle even the weakest microphone signals.

For studios that rarely want to record more than 4 analog and 4 digital signals at the same time, an unconditional purchase recommendation, especially since the retail price of 1,479 euros is a comparatively low price for what is offered.

Additional Informations:

- Focusrite is a British audio equipment manufacturer that was founded in 1985 by Rupert Neve, who is well-known in the music industry for his work on high-end mixing consoles. Over the years, Focusrite has become a popular brand among musicians and recording engineers, known for its high-quality audio interfaces, preamps, and other recording equipment.

The company's product line includes a wide range of audio interfaces, preamps, studio monitors, and software plugins. Focusrite interfaces are popular among musicians and producers for their high-quality sound and reliable performance, with models available to suit the needs of everyone from home studio users to professional recording engineers.

One of the most popular products in the Focusrite line is the Scarlett series of audio interfaces. These interfaces are designed to provide high-quality audio recording and playback for musicians and producers at a range of different price points. The Scarlett series includes models with anywhere from two to 18 inputs, and each interface comes with a range of software plugins and other features to help users get the most out of their recordings.

Another popular product from Focusrite is the Clarett series of audio interfaces. These interfaces are designed for professional-level recording and mixing, with features like ultra-low latency, high dynamic range, and low noise preamps. The Clarett series includes models with up to 26 inputs, making them suitable for large-scale recording projects.

Focusrite also offers a range of preamps, which are designed to provide high-quality amplification for microphones and other audio sources. The ISA series of preamps is particularly well-regarded, with models that are based on classic designs from the 1980s and 1990s. These preamps are known for their warm, musical sound and their ability to add character and depth to recordings.
In addition to hardware, Focusrite also offers a range of software plugins that are designed to work with its audio interfaces and other recording equipment. The company's plugins include emulations of classic analog gear, like the ISA 110 EQ and the Red 3 compressor, as well as more modern plugins for tasks like EQ, compression, and reverb.

Overall, Focusrite is a company that is known for its commitment to high-quality audio equipment, and its products are popular among musicians and producers all over the world. With a wide range of audio interfaces, preamps, and other recording equipment, Focusrite is a one-stop-shop for anyone looking to build a professional-quality recording setup.

- Rupert Neve is a British audio engineer and electronics designer who is widely regarded as one of the most important figures in the history of recorded music. Neve has been responsible for designing some of the most iconic pieces of audio equipment in history, including mixing consoles, preamps, and other studio gear.

Neve was born in Newton Abbot, England, in 1926. He began his career in electronics design during World War II, working on radar systems for the Royal Navy. After the war, he worked for a number of different electronics companies before founding his own company, Rupert Neve Designs, in the early 1960s.

One of Neve's earliest and most significant contributions to the world of audio engineering was the creation of the Neve 8028 mixing console. This console was designed in the early 1970s and quickly became the industry standard for recording studios around the world. The Neve 8028 was known for its warm, musical sound, and it was used to record some of the most iconic albums in history, including Pink Floyd's "The Dark Side of the Moon" and Fleetwood Mac's „Rumours."

In addition to the Neve 8028, Neve also designed a range of other mixing consoles, preamps, and other audio equipment. One of his most famous designs was the Neve 1073 preamp, which is still in production today and is widely regarded as one of the best preamps ever made. The Neve 1073 was used on countless classic recordings, including albums by The Beatles, Led Zeppelin, and Nirvana.

In addition to his work in electronics design, Neve is also known for his pioneering work in the field of acoustics. He was one of the first engineers to recognize the importance of room acoustics in the recording process, and he developed a number of innovative techniques for optimizing the acoustics of recording studios.

Neve has been recognized with numerous awards and honors over the course of his career. He was inducted into the TEC Awards Hall of Fame in 1989, and he received a Lifetime Achievement Award from the Recording Academy in 1997. In 2004, he was awarded an Audio Engineering Society Fellowship, and in 2013, he was awarded the Pro Sound News Lifetime Achievement Award.

Today, Neve is still active in the audio industry, and his designs continue to be highly sought-after by musicians and recording engineers around the world. His legacy as one of the most important figures in the history of recorded music is secure, and his contributions to the field will be remembered for many years to come.