When musicians and engineers talk to us about the Radial Engineering products they use, they often praise the impact Radial gear has on their sound. Here, we’ll look under the hood at one of the components that help us provide great-sounding technology, Jensen Transformers.
Why High-Quality Jensen Transformers Matter
The short answer is Jensen transformers ensure your sound comes across clearly, accurately, and as you intended. With over 40 years of design refinement and a 20-year warranty, Jensen transformers are built to last – making them as reliable as they are great sounding.
Jensen Transformers are a core component in many Radial products because Jensen set the standard for high-quality transformers in terms of frequency response, low distortion and phase deviation, high noise rejection, and accurate signal handling.
In our premium direct boxes like the passive JDI and the HDI, line isolators like the Highline & Highline Stereo, and other gear, including our JS2 and JS3 Microphone Splitters, Jensen transformers are critical to preserving tone and elevating performance because they offer a wider frequency response than other transformers, superior noise rejection, and ensure a clean, warm sound.
We’ll dig deeper into that later, but first…
Why Do Transformers Matter In Audio Gear, And What Are They Anyway?
The importance (and benefits) of transformers “depends on the needs of the circuit. Different circuits and applications can take advantage of particular traits of particular transformers,” explains Radial’s lead designer, W.C. ‘Hutch’ Hutchison. Including, he adds, “creative applications where a transformer is designed to add some desirable color or character. But the opposite is perhaps more common – the desire for the transformer to be as transparent as possible.”
At a basic level, transformers transfer audio signals via magnetic induction – allowing a signal to pass while isolating that signal, blocking hum, buzz, and ground loops to preserve the integrity of your tone. The result is a cleaner, clearer, and more reliable signal.
Without getting too deep into the gory details of varying magnetic flux and varying electromotive force, a transformer is a passive electrical device that uses the process of electromagnetic induction to transfer electrical energy from one circuit to another. Typically, in audio gear, they step up (increase) or step down (decrease) voltage levels between circuits or isolate two separate powered devices.
Transformer technology has existed for almost 200 years (since Michael Faraday invented the first transformer in 1831), and many different materials have been used in their construction over time. Typically, however, transformers consist of two (or more) wires/conductors wrapped around a core material. Unlike other electronics (which require a physical connection to pass energy/sound along), a transformer transfers sound waves via an electromagnetic field through a tiny ‘air gap’ in which your signal becomes, for lack of a better description, suddenly wireless.
As Radial founder Peter Janis explained back in the day: “A signal comes in into the primary coil as alternating current (AC), that current excites the magnetic field and generates current on the other side – (like) a magnetic bridge across which audio signal travels – with a Faraday Shield or Cage around it providing isolation to block buzz, hum, and radio frequencies. Direct Current (DC) is also blocked, eliminating ‘offset’ voltage at the output, which can cause clicks and pops when audio signals are switched.”
“Why Don’t I Know This? Should I Know This?”
Not necessarily. If your eyes glazed over for a minute, don’t worry – you’re not alone. Odds are few of us can explain in detail what’s going on in the guts of our smartphones but can still capture high-quality photos and video.
What you should know, however, is that high-quality transformers make an appreciable and audible difference in your sound – preserving the tone of your instrument, eliminating unwanted noise and distortion, and, by extension, the tiresome process of tracking down what’s causing that noise, thereby providing consistent and great-sounding results every time you plug in and play.
Conversely, Hutchison says: “There’s a huge range of quality among available transformers. Cheap transformers or the wrong transformer can chop low frequencies, cut high frequencies, and introduce unpleasant distortions. Some may introduce unpredictable high frequency resonance or be less effective at stopping hum, noise, and RF signals or pick up AC hum because of inadequate magnetic shielding. Quality transformers are found in quality audio equipment – it’s that simple, really.”
Jensen – Nobody Does It Better
What makes Jensen transformers exceptional for audio gear is their frequency response extends beyond the 20 Hz–20 kHz range of many other transformers – in many Jensen designs, to as low as 1 Hz. That enables them to avoid group and phase delay – issues that negatively impact the clarity of musical details, causing poorer fidelity in analogue signals (or a higher bit-error rate in digital signals). That means every note you play, “from deep bass to shimmering highs,” is reproduced accurately and remains intact.
By way of explanation, if you play a triad or hit a kick drum and phase delay kicks in, some of the low and high-end information will arrive at the output – and your audience’s input (their ears) at different times. Jensen transformers, by contrast, allow the fundamental note and all its overtones to arrive simultaneously.
Then there’s Jensen’s capability for handling high signal levels without introducing distortion – which is particularly important in the low-end, where much of the energy and sonic information of sound lives, regardless of the instrument you play.
Additionally, Jensen Transformers offer exceptional noise rejection via their Faraday Shielding and a ‘can’ enclosing the core often made of Mu-Metal – a composite metal whose composition, in tandem with a heat-treating process developed by Deane Jensen, minimizes low-end distortion and shields your signal from interference. Think of it as the equivalent of a tinfoil hat that, rather than (allegedly) protecting your brain from space lizards and/or the NSA, actually truly protects your sound from interference that can result from, say, putting your DI on top of something that generates a significant magnetic field, like an amplifier.
Better still, when you push a Jensen Transformer, rather than a harsh clipping sound or distortion, the result is an effect characterized by gradual, natural compression and a harmonic richness often described by Radial users as “vintage, musical, or warm.”
As Peter put it back in the day: “That’s one of the fantastic things about a transformer – not only do they solve problems with noise, they make things sound warmer and sweeter.”
Essentially, Deane Jensen got deep under the hood to improve transformers. Knowing phase shifting was a problem, he found ways to extend frequency range, experimented with various shielding options, and “changed the laminations by using combinations of steel and nickel, working on the winding techniques; all that black magic.” In short, Peter concluded: “What Deane figured out was that if you paid attention to this stuff, you improved sound dramatically.”
“Jensen created transformers with state-of-the-art performance and a culture that consistently manufactured each unit,” Hutchison adds. “Plus, they introduced comprehensive testing of every transformer produced. Besides that, Jensen’s documentation and data sheets are the most detailed and useful out there.”
So, Why Aren’t Jensen Transformers In Every Radial Product?
To address the common and uncommon pain points musicians and engineers experience on stage and in the studio, we create every piece of equipment with an eye (and ear) to problem solving. The decision to use Jensen (vs. another of our high-quality transformers) depends on the product and application. It’s a question of efficiency, the specific use case for a piece of gear, and cost.
Jensen manufactures premium transformers that are more costly than some other options. If we defaulted to including them in cases where they’re unnecessary, we’d be passing that cost on to customers. Additionally, if we used a one-size-fits-all solution, say, oversized custom-wound Jensen transformers like those in a studio piece like the HDI, in a JDI, that would increase the size of what’s meant to be a compact solution unnecessarily.
The same goes for using Mu-Metal vs. another type of shielding – in a JDI Mu-Metal offers tangible benefits because that device utilizes mic-level signals, which are highly susceptible to noise and RF interference.
Similarly, our Highline & Highline Stereo Passive Line Isolators are equipped with precision-wound Jensen transformers because they’re constructed specifically to ensure your signal is isolated from distortion and ensure your true tone comes across exactly as intended.
So, in those use cases, sonically and physically, Jensen is the ideal fit.
“There are plenty of examples of low fidelity transformers that damage music. With so many mediocre transformers out there, the goal should be to find the most appropriate and best transformers, whether one wants true transparency or a particular vintage flavor or effect, (and) do no damage.”
It’s like serving the song. We’re serving the needs of a particular piece of gear by evaluating which is the best transformer for a given device and use case, which allows Radial to offer products custom-designed and created for users with different needs and, frankly, budgets.
We look at what’s most important to you, the end user, and where the use of Jensen is most effective and necessary, sonically, to provide you with the best possible solution and outcome for a given problem and situation. That’s what has always guided Radial’s efforts and always will.
We hope this helps you understand why Jensen Transformers are such a fantastic and world-renowned product and why our use of them is critical for Radial to meet your needs whenever and wherever you make music.
Want To Know More?
Find out about Radial’s Jensen Transformer-equipped products at RadialEng.com or drop us a line at [email protected] – we’d love to hear from you – and for more information about Jensen Transformers check out Jensen-Transformers.com and the Jensen FAQ.
