John Atkinson compared the KSA-100S with the KSA-50S in August 1995 (Vol.18 No.8):
When I auditioned the Krell KSA-100S before publishing Bob Deutsch's review last September, I found, as did RD, that the '100S had a slight lack of dynamic drive. I felt this primarily to be a function of the amplifier's having a rather lightweight bass register—something I found surprising in view of the reputation of Krell amplifiers for powerful low frequencies.
Listening again to the KSA-100S after an interval of several months, I was struck by the same signature. The extreme lows were not as…
Sidebar 1: System
Analog: Fully dressed Linn LP12 (Lingo, Trampolin, Cirkus), Ittok, AudioQuest AQ7000nsx.
Digital: PS Audio Lambda transport, PS UltraLink processor, AudioQuest OptiLink Pro 2 ST datalink.
Amplification: my own Convergent Audio Technology SL-1 Signature preamp and a borrowed Krell KRC. A pair of Bryston 7B monoblocks (the non-THX version)—amplifiers whose sound I'm quite familiar with—served as a reference. I operated the Brystons in the parallel mode.
Interconnects: TARA Labs RSC Master and Purist Audio Design Colossus Mk.II (5m lengths for the preamp-to-amp…
Sidebar 3: Specifications
Description: Power output: 100W into 8 ohms (20dBW), doubles with each halving of load impedance down to 1 ohm. Frequency response: 20Hz–20kHz, +0.0/– .1dB; 1Hz–150kHz, +0.0/–3dB. Distortion: <0.1% at 1kHz; <0.5%, 20kHz, full power. Slew rate: 100V/µs. Input sensitivity: 1.4V RMS. Gain: 26dB. Damping factor: >60. Input impedance: 47k ohms. Power consumption: 100W, idle; 1400W, full power.
Dimensions: 19" W by 8.5" H by 19.25" D. Weight: 80 lbs (net).
Serial number of unit tested: 32-20216.
Price: $5500 (1994); no longer available (2007).…
Sidebar 2: Measurements
I measured the Krell KSA-100S in its balanced mode, repeating selected measurements in the unbalanced configuration.
Following the 1/3-power, one-hour preconditioning test, the KSA-100S's heatsinks were only moderately warm.
The KSA-100S's input impedance measured 47.3k ohms unbalanced, and just under 95k ohms balanced; its output impedance varied between 0.095 and 0.11 ohms, depending on the frequency and load (with the higher values at 20kHz). Voltage gain into 8 ohms measured 26dB, balanced or unbalanced. DC offset, though fluctuating slowly…
The great format battle of our time continues to rage between the Blu-ray and HD DVD camps. For many reasons, some discussed in the July installment of this column, this battle may be the last one waged over physical media formats. But whether either or neither format wins, the outcome will be decided on the basis of video quality—issues of audio quality are being ignored. This is unfortunate for audiophiles for two reasons. First, we have a big stake in whatever will be the standard medium for movies and music, but second, this battle makes it apparent that the major forces in the…
Me, I'm still a music guy. As my wife said, after watching and appreciating the drop-dead-gorgeous quality of HD video, "It's nice, but I don't see the big deal." I guess she's a music gal. On the horizon—perhaps to be unveiled this month, at the 2007 CEDIA Expo—is a new generation of players and processors that will take full advantage of the audio capabilities of these media. I hope that that will encourage the recording industry to release music titles of equal quality.
Audio Research MP1 multichannel preamplifier
Y'see? There's still a need for analog multichannel, and the…
Sidebar: Recordings In The Round
BERLIOZ: Requiem
Toby Spence, tenor; Roger Norrington, Stuttgart Radio Symphony Orchestra, Stuttgart Southwest German Radio Vocal Ensemble
Hänssler Classic SACD 93.131 (2 SACDs)
What an exciting surprise! Roger Norrington's earlier Berlioz struck me as lightweight, but this is a phenomenal Requiem that I find musically and sonically superior to the multichannel competition from Robert Spano (Telarc) and Maurice Abravanel (Silverline, Vanguard). While the big moments are thrilling, with the most intense Tuba Mirum I have experienced from a…
A moment of silence, please, for the mouse in my shed: I've had a trap there for weeks, baited with peanut butter—I should have just waited for the food poisoning to do its work—and the poor little bastard finally found it.
It was a bad end, but not as bad as starvation, or being swallowed by a snake, or torn apart by a house cat. He might also have died from a severe blow to the head, had the glass jar I threw at him three Saturdays ago found its target instead of the wall behind him. (That dumb stunt was made even more exquisitely stupid by the fact that the jar still had a little…
We've also spoken of transformer impedances—numbers that describe their primary and secondary coils—but those, too, can't be understood in isolation of the gear with which these coils will be used, or even each other. It's possible to describe the DC resistance of a coil simply by measuring it, but it isn't possible to describe the AC impedance of a coil without observing it at work, in a complete circuit with an exemplary source or load. Consequently, the impedance specifications published by transformer manufacturers should be thought of abstractly: For the most part, primary impedance…
Tweaks come and go. When a new one creates a buzz in audiophile circles, I generally prefer to wait and see if it's still around after the initial excitement has subsided. I'd heard about "audiophile" fuses some time ago, and although the likelihood of them making a significant difference didn't seem as farfetched as such tweaks as the "intelligent chip" or the "clever little clock," I didn't feel inclined to try them. I was persuaded otherwise by the confluence of two separate influences: a report by Michael Fremer, in the February 2007 Stereophile, that the HiFi-Tuning fuses produced a "…
