Lenbrook is the parent company of Bluesound, NAD and PSB speakers. It is now also home to MQA and the new suite of technologies that the brand now produces.
On a recent visit to Lenbrook HQ, which is based in Toronto, I had the chance to sit down with the group’s Chief Technology Officer, Greg Stidsen, and find out more about his hi-fi history, as well as dig more deeply into the NAD and Bluesound brands, in particular.
WHF: What do you do at Lenbrook?
GS: I’m the Chief Technology Officer, which in some circles people think of as being an IT job, but what I’m really doing here is exploring new technology for the audio space. I also manage many of the relationships that we have built with technology companies over the years.
How did you get started in hi-fi?
My interest in hi-fi started during my university days when my housemate bought a complete Quad system with ESL57 electrostatic speakers, Quad valve amps, and I believe it was an Acoustic Research suspended sub-chassis turntable.
That was a seminal moment for my career. I just fell in love with the idea that you could have audio of that kind of quality and hear the music that way.
After university, I went into teaching for several years, and then various changes of circumstances pointed me in a different direction. It was then that I decided to take my hobby – my passion for music and hi-fi – and share it with other people. So I started working in a speciality hi-fi shop in my twenties.
How did you become interested in audio engineering?
I’ve always been very technical. At university, where I studied fine arts, I also worked as a sound engineer for some of the student rock bands. This was back in the ’60s, and music was exploding. It was part of the counter-culture.
I loved music and didn’t have the talent to play an instrument, but I was able to use my engineering skills. On that side, I decided that specialisation wasn’t the road to take. I wanted to be more universal in my knowledge, and so learned how to do lots of things. Engineering and automotive engineering was something that I had done a lot of in my earlier days, before I had even got into art and music, so I had always been into it.
NAD is a long-running brand with a substantial legacy. What do you think it represents in 2025?
It still draws on its very early days of having high levels of engineering integrity with very nice usability. We try to make products that people enjoy using, and we aim to make them affordable.
The original 3020 is a hugely important product for the NAD brand. What do you think made it special?
What made that amplifier special was that our founding engineer, Erik Edvardsen, took the highest level of engineering and the highest level of spec available at the time and made a very affordable product out of it.
The trade-off was that it had a very simple casework and a relatively low amount of power; just 20W per channel. However, by carefully configuring the power supply and other elements of the circuit design, he was able to make that 20W sound bigger than it was.
NAD and sister brand Bluesound both lean heavily into Class D amplifier technology. Could you explain the benefits and potential downsides of doing so?
Every amplifier class has advantages, disadvantages and applications. For many years, Class A amplification was considered the pinnacle in terms of sound quality, but it had so many drawbacks. It was not practical for high-power, high-efficiency applications – the heat, the cost, the weight, the power consumption; all those things are issues.
Class D was invented in the ’60s in the UK. Early on, it was quite crude, but it was an interesting concept because the efficiency was so high. So, as we moved into the 21st century, it became clear to us that such designs were getting better all the time. It was obvious that this was the direction that we needed to go, as there was going to be continued pressure to get ever-higher efficiency and lower power consumption.
There were some fundamental things about Class D architecture that eliminated some problems with Class A/B. Class A/B is in many ways something of a compromise to get close to Class A’s performance but with the efficiency of a Class B. Class D wasn't really such a compromise. It was a new way of looking at amplification.
With an increasing number of sources becoming digital, you could make a Class D architecture that was a pure digital amplifier. In our first Class D offering, the M2, we used technology that we called Direct Digital. It was, in fact, a DAC that amplified.
Class D makes a lot of sense with smaller products, and there is a great advantage with active speakers. The big thing is the fact that pretty much all the power that goes in is used to drive the speakers. In comparison, Class A is around 20 per cent efficient, and Class A/B is around 40 per cent efficient. Admittedly, Class D at idle isn’t super-efficient, but it is still better than A/B.
When it comes to power supplies, we have largely moved from linear designs to switch-mode, because they are very well regulated and inherently stable. This makes them a good match with Class D circuits, which aren’t very tolerant of voltage variations. Switch-mode supplies give you that rock-solid stability.
What is your favourite NAD product?
I have so many. I think the M2 was a very important product for us. We did something called the Master’s Digital Music Suite, which was the M50, M51, M52 combination. This was kind of a precursor to our BluOS software development, and so I feel very strongly about that. What we did with the D 3020, reinventing an entry-level amplifier for music lovers, I feel like that made it an important product for the brand.
What system do you have at home?
My primary listening system uses the M66 and M23. I have used a variety of speakers and currently have a pair of Magnepan MG1.7 partnered with some custom subwoofers that are built into the floor. I also have a home cinema set-up that uses PSB speakers, a NAD M17 processor and some additional NAD power amplification.
What music are you currently listening to?
Ry Cooder’s Paradise And Lunch has been in constant rotation recently. I’ve been listening to a lot of Captain Beefheart and have been going through his catalogue. I love the psychedelic period of music from the '60s, so I am rediscovering some of that. I also like a lot of jazz and classical music, and am a big Thelonious Monk fan.
Having joined NAD in 1996, you have seen a lot of changes. What do you think hi-fi will look like in 30 years' time?
That’s an interesting question. At that point, we could have implants in our brains!
Okay, that’s kind of far-fetched, but I think there is a sustainability to the stereo package, as there is so much recorded material. I am doubtful about immersive recordings, though. I know a lot are being recorded, but I’m not convinced.
MORE:
Read our five-star NAD C 3050 review
And our Bluesound Node (2024) review
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