Review: Alderwood Eros Pro

Review:/ Christopher Holder

TALK IT OUT

You can a transcript of my interview with Scott Wilkinson later in this article and for anyone interested in loudspeaker design, it’s an interesting read. Here’s a local talent who has established a cool, made-in-Australia business and is finding a real niche for his engineering chops.

Yes, there are other small-format, sub/satellite loudspeaker systems out there. Doubtlessly there are cheaper alternatives as well. But few will be as well suited to the constant punishment these Alderwood Eros Pro units have been designed to withstand. Even fewer will include a beautifully milled brass ball joint for mounting. And few will sound as lively and as articulate as these.

If you’re curious, I can recommend a drive out to Cobden for a listening session with Scott. Hearing is believing.

Tiny Speakers, Big idea: An interview with Scott Wilkinson, Alderwood Speakers

AV: Alderwood is almost exclusively known for its miniature speakers. What put you on that trajectory?

Scott Wilkinson: Actually, I used to build tower speakers – the bigger, the better. If it took two people to lift it, that was a win for me. We had subs with the surface area of equivalent of twin 12-inch drivers. I was working with Tymphony’s LAT700 technology – stacked drivers connected with carbon fibre rods.

That was a 10-year journey – chasing the perfect big speaker. Meanwhile, my wife had been hounding me for six months: “I want a small cube speaker.” Eventually she slapped $500 on my bench and said, “I’m a paying customer, give me my speaker.”

I told her to keep her money, went to the shed one Sunday, and built a little sub and two very rough cube speakers. I didn’t measure them, I just threw them together and gave them to her. I popped them on top of the tower speakers, turned them on, then walked to the kitchen at the other end of the house and noticed it was still really loud.

When I got back, my wife and brother were on the couch and said, “Hate to tell you this… but we prefer the cubes.” I was annoyed, so I took them back to the shed, measured them, and realised: the on-axis response was good, and the off-axis response was still solid. That was surprising – most speakers drop off in the highs off-axis. Silk domes are okay, but they don’t project much. The two-inch diaphragm on this particular unit could really throw high frequencies.

That was the turning point. I spent the next three years perfecting the design, shrinking them down, and understanding what made it work – and what didn’t.

AV: That explains your small-speaker fascination. What’s the origin story for this new product, Eros?

Scott: FaitalPro reached out to us probably about 12 months ago. They wanted to share their OEM catalogue. I was scrolling through it and noticed a new driver – it had really high sensitivity specs, quite good low-frequency extension, and it was only two and a half inches across. A few months later we got our first production run to work with.

In our tests this new driver was particularly difficult to work with – not because of strength, but because of its unique design. With small drivers, you need a manufacturer who knows how to do glue joints properly. The forces on those joints – especially where the voice coil attaches to the cone – are just so much greater than with a standard-sized speaker.

AV: Why is that?

Scott: Take a large sealed box – it has a lot of air compressibility. There’s some give. But a smaller box has very little compressibility – there’s no give. So the first point of stress becomes the glue joints – pressure builds up and stresses the structure.

AV: Sounds like you went through a bunch of drivers on your way to finding the right design?

Scott: Our prototyping process involved building around 200 designs. We don’t get attached to any of them – we build, listen, test, measure, and put them through a power response test. Our products get absolutely tortured all day, every day, especially in commercial use.

You might find a box that sounds sweet at 1W but completely falls apart at full power. So we’re also testing how well a design fills a space. That’s the kind of performance people expect from us.

AV: Sounds like a paradox: small speakers filling a large space.

Scott: Yes. But smaller speakers have excellent off-axis response, so they can very effectively fill large spaces. Larger speakers tend to beam more. You can use lenses and other tricks to correct for that, but anything you put in front of the driver potentially introduces distortion.

AV: What else makes a small speaker feel like it fills a space?

Scott: You need a high-sensitivity driver to begin with. If sensitivity is too low, you run into power compression – basically creating heat instead of sound. Some small speakers fail in that regard. That’s why we tune everything at max volume – we want peak performance at full power, not just at 1W.  A driver that would fall apart on a test bench survives once enclosed and can run for 10–12 hours straight.

AV: Why is that?

Scott: We fine-tune our enclosures with a valve system that regulates airflow and pressure. It controls excursion – like a passive servo system. It prevents excess power from hitting the driver at its tuning frequency. So it’s like a passive crossover, but with no components – keeping phase coherence and simplicity.

AV: So you started with a sealed box?

Scott: Yes. The sealed box was our baseline. Around 70% of our speakers are used outdoors or on boats, so we needed weather resistance. But sealed designs have limits – especially in bass extension. Even a standard ported box gives you 3dB more at tuning. This new design is all about extracting the maximum possible performance from a small enclosure. Compared to our previous design, our new speaker delivers a 12dB gain from 500Hz down to 80Hz. That’s a huge difference. We didn’t have much at 80Hz before – it’s not a full-range speaker, but it allows us to use a much lower crossover point where it hands over to a sub.

AV: That extended response in the 80-500Hz range, is that primarily down to the FaitalPro driver?

Scott: Partly. But more so our ability to modify the driver. We don’t use anything off-the-shelf – we make several adjustments. With small speakers, even minor changes make a big difference. For instance, if you bolt a speaker directly to the enclosure, you couple it – vibration reflects back into the driver, creating resonances.

So none of our screws touch the driver. It’s fully encased in rubber, completely decoupled from the cabinet. I picked up that idea from Japanese audio design back in the mid-90s. They used nylon bolts with limited torque to minimise resonance in horn-loaded enclosures. That stuck with me.

Now we use a gentle clamping mechanism. Our pass/fail regime is strict – too much torque and the driver fails. It’s that sensitive.