Raw Power, Refined: Linea Research Emerges With A Range Of Innovative Platforms

Linea’s strategy proved to be spot on. While every loudspeaker manufacturer at the time seemed to be placing a priority on self-powered designs, trying to do DSP and all of the supporting electronics involved was a difficult and costly proposition.

“Many thought they could do it all themselves,” Ver notes. “Others realized there was a lot more to it, and that the devil was in the details. Those in the latter camp saw the advantages of working with us. Our technology was different, and after all, you simply can’t put a conventional 1,000-watt class A/B amplifier, let alone two of them, in the back of a speaker, so it has to be class D.

“We then began to dispel the bad connotations associated with the sound quality of the class D amplification of the time by proving that excellent sonics were possible.”
Williams adds, “We focused on ensuring that these products were designed to perform in real-world circumstances, not just for the data sheet.”

Ver provides additional insight into exactly how that goal was achieved. “Our class D designs look deceptively conventional, and in a way they are, being based on the classical half-bridge topology. The problem is that, unlike class A/B or related designs, there’s not a great deal of scope for using large amounts of negative feedback to band-aid either component deficiencies or plain poor design. The only way to deal with problems is to not create them in the first place.

“Even though X-Pod was Linea’s first amplifier product, it was my fourth or fifth class D design, so I was well past the point of struggling to get it to work reliably,” he continues. “As a result, I was able to spend my efforts really understanding and optimizing the complex way that the various parts interact, particularly in the output stage, to achieve a result that was very clean even before feedback was applied.

“If you add to this power supplies designed specifically for the task at hand – audio, rather than culled from the computer industry – and a deep understanding of how to integrate sensitive analog circuitry and DSP in very close proximity to massive power electronics without compromising their performance, you start to have a recipe for great-sounding products.”

Integrated Whole

One of the next building blocks within Linea’s worldview is the ObCom protocol. Conceived based on the belief that networking would play a large and dominating role in the future of loudspeaker systems, ObCom first revealed itself to the industry as a versatile, object-oriented messaging technology.

Ultimately moving on to become the backbone of many of the company’s product offerings, ObCom provided the power and capability for control of a single component or the power to configure and monitor hundreds of devices spread across multiple networks. In short order, it became the fabric that tied together disparate elements of a system into an integrated whole, with connectivity internally within components, between devices, and spanning entire networks.

As Linea’s self-powered loudspeaker OEM work flourished, the company began to make progress on other fronts as well.

Linea makes all of its own test equipment for production, and this is one example.

“At this point we had developed extremely high quality, powerful loudspeaker DSP,” Williams notes. “We had a lot of knowledge of A/D converters and digital electronics, and as an early partner with Audinate, we’d even developed Dante digital networking interfaces for some of our OEMs. But we didn’t stop and rest upon our laurels.”

One of Linea’s silicon vendors had created a prototype breed of power semiconductors for an unrelated industry. Inspired, Ver initiated the design of new proprietary output stage circuitry that advances efficiency.

“If the output stage is more efficient, then the product as a whole generates less heat,” explains Rik Kirby of Allied Professional Technologies, the U.S. sales and distribution arm of Linea. “Our circuitry can produce as much as 20 percent less heat than other class D designs, depending on whom we’re comparing ourselves to. That has a direct benefit not only in terms of how warm our rack-mount amps keep a monitor engineer’s knees, but also in terms of the energy we need to invest in the first place. Less current is drawn since there’s less energy being wasted, so we’re able to store more useful energy and hold it in reserve, sustaining power delivery for a longer time.”

Williams states that Linea took the same intensive approach when researching and developing the DSP engine and algorithms. “There’s so much more to it than the number of bits or the sample rate,” he details. “With my background in high-quality analog design, I understood the demands that the uniquely sensitive human ear placed on this area. Our handcrafted DSP algorithms draw every last ounce of performance from the DSP silicon, using techniques we collectively call Linea Micro Detail (LMD), details you can hear.”