search

Each speaker was submitted to the following measurement schedule: The voltage sensitivity was assessed with 1/3-octave pink noise centered on 1kHz, while the change of impedance with frequency was measured using spot tones (footnote 1). The nearfield low-frequency response of each speaker was assessed with a sinewave sweep to get an idea of the true bass extension relative to the level at 100Hz.

The frequency response of each speaker in the listening area was measured using pink noise and an AudioControl Industrial SA-3050A 1/3-octave spectrum…

You always meet interesting people in the stairwells of hotels. Whether this is because the more interesting a person is, the more easily they become frustrated at having to wait for an elevator, or because they feel better at having expended a little physical energy, who knows? But so it proved at the 1992 Summer CES when, working my way down the Chicago Hilton's floors one by one in my usual pedestrian manner, I bumped first into David Clark, then John Eargle (footnote 1), and…

Two families of digital filters are realizable with such a DSP chip: FIR and Infinite Impulse Response (IIR) types. An FIR filter, which in the real world of limited hardware resources is best suited to…

I asked Digital Lad Robert Harley to come over for a second opinion…

To finish my auditioning sessions with the DLP600, I dug my 1982 pair of original Celestion…

There has been considerable published work in recent years on the use of filters operating in the digital domain to optimize loudspeaker performance. Those interested should read the following papers: "Efficient Filter Design for Loudspeaker Equalization," Richard Greenfield and Malcolm O. Hawksford, JAES Vol.39 No.10, October 1991; "Digital Equalization Methods for Audio Systems," J. Mourjopolis, and "Application of Digital Filters to Loudspeaker Crossover Networks," Rhonda J. Wilson, J.B. Scott, and the late Glyn J. Adams, both presented at the 84th AES…

The reference system used to audition the SL600Sis and the effect of the DLP600 is the same as that used for my past few reviews. The all-digital nature of the DLP600 meant that analog playback had to be (temporarily) abandoned, however. Source components consisted of a Meridian 602 CD transport driving either a VTL Reference D/A processor or the Audio Alchemy DDE. Digital interconnect between the Meridian and the DLP600 was a 1m length of AudioQuest's new Digital Reference; between the DLP and the DACs I used a 0.5m length of the Mod Squad's Wonderlink.…

Before I examined the measured effect of the DLP600, I ran the SL600Si through Stereophile's almost standardized test regime. Fig.1 shows the manner in which the speaker's electrical impedance magnitude and phase vary with frequency. The single peak of 30 ohms at 63Hz indicates the sealed-box tuning frequency. The speaker is an easy load, apart from the drop below 6 ohms above 4500Hz. Though this dips to 2.7 ohms at 34kHz, there is insufficient musical energy in this range to lead to any problems. Note the sharp impedance peak at 21kHz; this is due to the…

Fig.10 Celestion SL600si equalized by DLP600, impulse response on tweeter axis at 45" (5ms time window, 30kHz bandwidth).

To look at what is happening from a different viewpoint, the MLSSA…

It has been some 250 years since Jonathan Swift's Captain Gulliver tangled with the inhabitants of the land of Lilliput. In the interim, it appears to me that a significant number of Lilliputians have succeeded in infiltrating the British Isles. How else am I to account for the uniquely British craze for miniature loudspeakers? The BBC, rumored to be a Lilliputian stronghold, started it all when they licensed commercial production of the LS3/5A minimonitor. The ProAc Tablettes followed shortly thereafter, and managed to…