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With the audio system in the room that now houses what passes for a "Home Theater" setup, I had been extremely underwhelmed by the spatial effects on this LP. I realize now that the primary reason for the ho-hum presentation was that that room was a nightmare for imaging, with a sliding glass door for the right wall, no wall for the left wall, a ceiling that slopes downward from left to right, a partial wall behind the speakers...I could go on, but you get the idea. But neither was I certain that part of the problem wasn't because it was an LP, not a CD, figuring that maybe those tricky…
As for 1, this wasn't a problem with most music I listened to; however, pieces that tended to flex the walls and let me feel the low notes, via the Vandersteens, had less impact with the Thiels. "The Gates of Däfos," from Däfos (Reference RR-12 CD), was a good example of this: when The Beast gets dropped, I didn't feel it with the Thiels, whereas I did with the 'steens (and even more so with mightier bass-reproducers).
Now for 2: we're not quite talking "one-note bass"—more like "two- or three-note bass." I could differentiate the pitch on these lower notes, but just. Not bad for what's…
Sidebar 1: Specifications
Thiel CS.5Two-way, ported, floorstanding loudspeaker. Drive-units: 6.5" paper-cone woofer, 1" aluminum-dome tweeter. Frequency response: 55Hz-20kHz ±3dB. Phase response: minimum ±10 degrees. Sensitivity: 87dB/2.8V/m. Impedance: 4 ohms, 3.2 ohms minimum. Recommended power: 30-150W.
Dimensions: 8" W by 11" D by 31" H. Weight: 35 lbs.
Serial numbers of units reviewed: 0545/6.
Price: $1350/pair; $1380/pair, West Coast price; walnut or black finishes (optional finishes extra). Warranty: 10 years. Approximate number of dealers: 55.
Manufacturer: Thiel,…
Sidebar 2: Measurements
Unusually, I found the CS.5 to be a little more sensitive than its specification suggests, at about 89dB/2.83V/m (B-weighted). Its impedance, however, is, as with all Thiels, quite demanding, as can be seen by taking a gander at fig.1. Remaining below 6 ohms pretty much throughout the bass and midrange, it drops to a minimum value of 3.3 ohms at 200Hz. It does stay higher in the treble, however, and the electrical phase angle (dotted trace in fig.1) is generally lowish. But "8 ohm-rated" A/V receivers should still be shunned by Thiel owners if "cheap-amplifier…
Fig.4 shows a similar set of dispersion curves, this time in the horizontal plane. The '.5's output is maintained across the band to about 20 degrees off-axis. Beyond that angle, a cancellation notch appears in the low treble, and the high treble falls off more rapidly than is usually seen with a 1" dome tweeter. It is difficult to predict the subjective effect of such behavior. I suspect that in all but very dead rooms, the mid-treble flare at the bottom of the tweeter's passband will to some extent compensate for what might otherwise be too polite a tonal balance.
Fig.4 Thiel CS…
In the fall of 1982, I had just become the Editor of the English magazine Hi-Fi News & Record Review. Hi-fi was in a state of flux. The Compact Disc had just made its debut in Japan, but the British and American launches were six months and a year away, respectively. The Linn orthodoxy prevailed about the role of the source in system performance, but there was no agreement about what was and was not important when it came to enhancing the musical experience. "Objectivists" insisted that amplifiers and even loudspeakers had pretty much reached a design plateau where no further improvement…
Compared with the Stereophile-owned pair of Mark Levinson No.20.6es that reside in my listening room, the Krell '50S had a noticeably less extended, weighty bass. This is hardly surprising, considering the Levinson monoblocks have fully regulated output-stage power supplies and cost five times as much. What did surprise me was that the KSA-50S had a more liquid-sounding midrange. Eric Clapton's rather dead-sounding vocal on "Motherless Child," from From the Cradle (Reprise 45735-2), was more palpable, more solid. The difference was analogous to that between, say, Kodak Tri-X film and Ilford…
Sidebar 1: Specifications
Description: Solid-state stereo power amplifier. Specified output power: 50W into 8 ohms (17dBW), doubles with each halving of load impedance down to 1 ohm. Maximum output voltage: 75.8V peak to peak, 26.8V RMS. Maximum output current: 60A. Frequency response: not specified. Distortion: 0.018% at 1kHz; 0.18% at 20kHz, full power. Signal/noise ratio: >100dB. Input sensitivity: 1.34V RMS. Gain: 26dB. Input impedance: 47k ohms.
Dimensions: 19" W by 14.25" D by 8.5" H. Weight: 52 lbs (net).
Serial number of unit reviewed: 31-10530.
Price: $3300.…
Sidebar 2: System
My digital front-end consisted of a Mark Levinson No.31 CD transport and an Aiwa portable DAT recorder, both driving an HDCD-equipped Mark Levinson No.30.5 via either a Sonic Frontiers UltraJitterbug or an Audio Alchemy DTI•Pro (original Star DSP version with v2.7 software) (footnote 1). My real-world digital source was a Parts Connection Assemblage DAC-1 processor. Digital datalinks included Madrigal, AudioQuest, and Illuminati AES/EBU cables and ASM Labs Mamba ST optical fiber.
The phono front-end consisted of a Linn Lingo'd LP12 fitted with an Ekos arm and…
Sidebar 3: Measurements
I primarily measured the Krell KSA-50S in its balanced mode. Unusually but gratifyingly, Krell provided a full set of Audio Precision measurements for the review sample. (I wish more manufacturers did this!) The '50S's two bias LEDs came on at 8 ohm output power levels of 765mW (red) and 25.2W (blue). Though the KSA-50S's heatsinks were hot following the 1/3-power, one-hour preconditioning test, I could still keep my hand on them.
The KSA-50S's input impedance measured 49k ohms unbalanced, the same for each leg of the balanced input; its output impedance…