Laboratory Test Report
Readers interested in a full technical appraisal of the performance of the Dellichord FR6 loudspeakers should continue on and read the LABORATORY REPORT published on the following pages. Readers should note that the results mentioned in the report, tabulated in performance charts and/or displayed using graphs and/or photographs should be construed as applying only to the specific sample tested.
The in-room frequency response of the Dellichord FR6, as measured by Newport Test Labs, is shown in Graph 1 and is the averaged result of nine measurements, made in a square grid with the tweeter at the central axis, using pink noise as a stimulus. You can see that the response extends from 55Hz to 20kHz ±3dB (though 20kHz is simply the upper graphing limit for this test — the FR6’s high-frequency response extends above 20kHz, as shown in Graph 2).
Importantly, the linearity of the response across the most important part of the frequency range — the seven octaves from 100Hz to 10kHz — is within ±1.25dB, which is exceptionally flat. There’s a very, very slight rise in the response between 300Hz and 2kHz that past experience would suggest is an indicator that these speakers will be very kind to the sound of female vocalists, and will also give reproduced music a more ‘live’ sound quality.
The high-frequency response of the Dellichord FR6 is shown in Graph 2 and was measured using an electronic gating technique that simulates the result that would be obtained in an anechoic chamber. It shows the response with the loudspeaker grille in place (red trace) and without it (black trace). The two traces are so similar that they’re essentially identical.
There is a slight loss of volume when the grille is used, but it’s almost independent of frequency, thus frequency balance is unaected. The slight dip in response below 3kHz is a microphone
Use a moderately highpowered amp if you wish to generate high sound pressure levels in your listening room
positioning eect that occurs when a single trace is used, as in this case, rather than a grid average (as in Graph 1). You can see that the response remains within the ±3dB envelope out to 25kHz, after which there’s a very slow roll-o to 33kHz. This extension means the overall frequency