Australian Hi-Fi

LABORATORY TEST REPORT

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Newport Test Labs measured the frequency response of the Revel Concerta2 M16 speaker as 45Hz to 22kHz ±4dB, which is an excellent result and shown in Graph 1. You can see from this graph that the response is particular­ly flat between 250Hz and 12kHz where, except for one small discrepanc­y centred at 5kHz, it’s essentiall­y within ±1dB. Also note that this is a very high-resolution graph without any smoothing—the human ear would actually hear the in-room response that’s shown in Graph 5.

In Graph 2, Newport Test Labs has again used a high-resolution measuremen­t technique and also extended the high-frequency limit of the measuremen­t up to 40kHz. The peak at 23kHz is a resonance caused by the use of aluminium as a dome material. Luckily, being at 23kHz it’s well above the limit of perception for almost all humans, but even the few that could hear this high a frequency would be unlikely to be able to detect the peak, due to its very high Q. The same could be said for the extremely sharp dip in response that follows immediatel­y after. The tweeter is certainly a hi-res type, as demonstrat­ed by its response extending easily out to 40kHz, and by the look of it, likely far above this frequency.

This graph shows the difference in response between using the Revels with their grilles fitted (red trace) and without. Although there are some minor difference­s, I doubt they’d be audible, so I’d plump for listening with the grilles on to ensure added physical protection for the drivers.

Low-frequency response is measured by Newport Test Labs using a near-field technique that simulates the response that would be measured if the speaker were in an anechoic chamber, and is shown in Graph 3. You can see the bass/midrange driver starts rolling off at 100Hz to a minimum at 45Hz which is the expected behaviour for a small bass/ mid driver in a small-volume bass reflex enclosure. What I didn’t quite expect was the performanc­e of the port, which rather than being peaky is instead quite flat, delivering a sustained equal-volume output from around 30Hz up to 70Hz. This would not only contribute to improved bass output, it would also mean the bass from the Concerta2 M16 would sound different to bass from a speaker with a convention­al bass reflex alignment.

The impedance of the Revel Concerta2 M16, as measured by Newport Test Labs (Graph 4), shows that the speaker will require your amplifier to deliver adequate current between 120Hz and 270Hz, where the impedance is around 5Ω or lower, but this won’t be a particular­ly difficult task because the phase (blue trace) is reasonably benign (±30°) across this frequency range. Don’t skimp on amplifier power and make sure the amplifier you use will comfortabl­y drive 4Ω loads. The impedance plot is otherwise unremarkab­le, other than to say there are no cabinet resonances, which is good, and the modulus is constraine­d between 4.2Ω and 28Ω, which is also good.

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