Flare Audio believes that loudspeakers should provide 'as pure a sound as possible', to enable an unaltered reproduction of the sound created by the musician. In its white paper, the company defines a sound as 'pure' if it loses none of its detail in the transmission from artist to listener in the process of audio reproduction.
The paper explains how most loudspeaker designs damage sound through resonance and internal reflection within the cabinet. It also describes how manufacturers have traditionally compensated for this, particularly in the last two decades, by the use of digital correction techniques using DSP.
A Waveform integrity test measures a sound wave at its point of origin and also as it emerges from the loudspeaker. The more closely the two waves resemble each other, the better the quality of sound reproduction. A Wi test is carried out with a dual channel oscilloscope (ideally, high resolution) and an RTA microphone. By adopting this test, purchasers will be able to initially judge the quality of a loudspeaker simply by comparing Wi measurements in marketing material, prior to hearing a product first hand.
"The Waveform integrity test is not intended to replace other testing methods," says Davies Roberts, Flare founder and author of the white paper. "It is designed to provide further information to the user in order to better evaluate the sound quality of a loudspeaker."
The paper concludes with the recommendation, "We believe that both the user and the industry will benefit from the application and disclosure of Waveform integrity tests. This white paper puts forward the case for European and International standards boards to raise the standard of disclosure to users by requiring that Waveform integrity test results be included in user information for every loudspeaker sold."
Further to the publication of this story, LSi Online received a letter from audio consultant Jim Cousins, of Sound Improvement Services. Jim's letter, and the ensuing correspondence with Davies Roberts of Flare Audio, appears below:
Letter to the EditorI read the article 'Flare Audio backs Waveform integrity' at LSiOnline - and checked my calendar to see if it was April 1st.Flare's 'Waveform integrity' tests using an oscilloscope appear to be nothing more than an attempt to hijack an existing checking technique (displaying the measurement mic signal on an oscilloscope) as a marketing ploy. We all use 'scopes for visual checks - and then back them up with THD and IMD distortion analysis, impulse analysis, noise and signal coherence checks, as a matter of course. Checking for any type of an anomaly at spot frequencies only is a huge backwards step.Measurement techniques have moved on and loudspeakers have improved as a result. I thought the loudspeaker industry left this kind of thing behind in the 1990s.I'm all for clever marketing campaigns and genuinely new measurement techniques - often taken from other industries but new to the audio business - and I certainly back any move to encourage distortion measurements vs SPL level to be included in loudspeaker specifications - but manufacturers implying that they have invented something that has been done as a matter of course since the mid-20th century can be very irritating.Unfortunately, this kind of approach dilutes a lot of genuine education that goes on in
