Getting Real Sound Out of Mordaunt Short Avant 906i Speakers
The Avant 906i is a bookshelf speaker from Mordaunt Short, a British brand that has been around since the 1930s. These are three-way designs with a 6.5-inch bass driver, a 5-inch midrange cone, and a silk dome tweeter. They ship with a small booklet that basically says "plug them in and enjoy." That's not enough information if you actually want them to sound right. My first experience with a pair of these was about four years ago. They arrived in cardboard, wrapped in foam, with nothing but basic specs on the back. The frequency response is listed at 42Hz to 25kHz, sensitivity is 88dB, and they handle 15 to 120 watts. Real-world numbers tend to differ from what the spec sheet claims, and I'll get to that. Start with placement. These speakers need room. I've seen people push them flat against a wall and then complain the bass sounds boomy and undefined. The 906i has a rear-firing port, and if you put it closer than 15 centimeters to a wall, the bass reflex output stacks with itself and everything below 80Hz turns into mud. Move them out 20 to 30 centimeters and you immediately hear more definition in the lower register.
Tweeze them in slightly, too. Angling them so they point at your listening position rather than shooting straight ahead usually tightens up the stereo image. I use a simple protractor app on my phone to get the toe-in angle around 15 to 20 degrees. Don't obsess over it. Even degrees make a noticeable difference on these, but they aren't that finicky.
The Amp Question
These speakers are rated at 8 ohms nominal impedance, but like most Mordaunt Short products, the impedance curve dips. The actual impedance hits around 5.5 ohms at certain frequencies, which means some amplifiers will struggle more than the wattage rating suggests. I ran a pair through a Rotel A12 integrated amp at moderate volumes and it handled them fine. The same speakers with a weak solid-state amp from the budget end sounded thin and strained, especially on complex passages. Class-A or Class-AB amplifiers tend to match better with these drivers. The midrange cone on the 906i rewards clean current delivery. If you're running a switching power supply amp or something aggressively compressed, you might find the sound a bit harsh above 4kHz. I learned that the hard way with an old Denon I had lying around. Swapped to a Musical Fidelity M1 and the sibilance dropped out completely. Not a perfect match for every system, obviously, but worth knowing.
Get the Full Details
Break-In and Calibration
Mordaunt Short uses a paper composite cone for the midrange driver, and paper needs time to loosen up. The first 50 hours will sound somewhat stiff and closed in. I usually run pink noise through them at low volume during break-in because it's consistent and doesn't damage anything. After that, the midrange opens up noticeably. Around hour 100 they settle into their natural character. Room treatment matters more than people think here. These speakers reveal room modes. If your listening room has hard parallel walls, you'll hear it. A cheap rug, some acoustic panels, or even bookshelves with irregular spacing will smooth out the response. I measured mine with a REW (Room EQ Wizard) setup and a calibrated microphone, and there were clear peaks and dips in the 60 to 120Hz range from room modes. A subwoofer or a small DSP-based room correction unit can help, but I prefer keeping it analog where possible.
What They Actually Sound Like
The bass is decent for the size but not deep. If you're listening to orchestral music or electronic material below 50Hz, you'll want a sub. The 906i rolls off gracefully after that, but it doesn't claim to go lower. The midrange is the real strength. Vocals, acoustic guitars, and brass sound natural without being pushed forward artificially. It's not a bright or aggressive sound, which some listeners might mistake for dull. It's just restrained. The treble extension is listed at 25kHz, which is above human hearing range, but the silk dome does make the upper harmonics feel smooth rather than fatiguing. I've run them for six-hour sessions without ear fatigue, which says something. That said, poorly recorded or overly compressed material will still sound harsh regardless of the speaker.
Edge Case: Matching with a Turntable
I connected these to a Rega Planar 3 with an Ortofon 2M Blue cartridge through a prologue preamp. The Mordaunt Short's 88dB sensitivity is adequate but not. At lower volumes, the vinyl detail didn't come through as clearly as I wanted. The workaround was simple: I added a small phono stage gain boost and raised the volume slightly. The nuance appeared without any distortion. If you're using a moving coil cartridge, you'll definitely need a quality step-up or a preamp with enough gain to drive these properly. They are not monitors. If you need flat, reference-grade response for mixing or critical listening, look elsewhere. These are musical speakers, colored by design in the sense that they prioritize warmth and cohesion over absolute neutrality. They also have a relatively narrow sweet spot compared to planar magnetic alternatives. Sit two meters back and centered and they open up nicely. Step to the side and the imaging collapses a bit. The build quality is solid but unremarkable. MDF cabinets, basic grilles, standard binding posts. Nothing fancy. For the price point, that's fair. If you're spending more, you're paying for materials and finish, not dramatically better sound from this driver array.
Bottom Line
The Avant 906i is a competent speaker that benefits from proper placement and a capable amplifier. They reward patience and a decent source. They won't win any technical measurements contests, but they deliver a coherent, musical presentation that works well for jazz, rock, vocals, and acoustic material. Just don't expect them to fill a large room with bass or reveal every flaw in a recording. They're honest speakers that do their job without pretense.
