"Here's an idea:…
"Here's an idea:…
Don't lose that number
Editor: Regarding John Marks' call for the "extra-credit essay question" about Steely Dan's "Rikki Don't Lose That Number": No essay required, as your editor, John Atkinson (a fine bass player himself), already knows. The bass line for the tune has no relation to Coltrane's piece but is, in fact, a quote of the bass intro to Horace Silver's "Song for My Father," the Blue Note sessions for which occurred just a month and a half prior to Coltrane's Impulse! recordings.
Sorry, just couldn'…
Somehow, there always seemed to be more urgent jobs that needed to be done around the house—new roof, new main drainage, new bathroom, new…
In order to control the listening experiment as tightly as possible, only one component in my reference system was changed at a time. Initially it was the amplifier. The KSA-250 was substituted for the Mark Levinson No.23, with the rest of my reference system intact: a Theta Pro (balanced) Generation Two digital processor and Mark Levinson No.26 line-stage preamplifier, all operating in balanced mode, using Madrigal HPC interconnect. My B&W 801 Matrix Monitors were bi-wired with the same AudioQuest Clear speaker cable I've had for about a year (not…
It's somewhat unusual for two reviews of a product, by different reviewers, to appear in the same issue. However, JA asked me to relate my impressions of the Krell KSA-250 for several reasons: I'd been listening to the KSA-250 as a basis for comparison with the comparably priced Threshold S/550e amplifier (see review this issue), and I'd spent some time with the KSA-250's predecessor, the KSA-200, in the same system and room. The KSA-250's performance could thus be put in perspective with the older unit, as well…
There is some diversity of opinion over whether an amplifier under bench testing should be supplied with whatever AC power comes from the wall (as it would see during normal use), or if the voltage drop should be compensated for by a Variac. The former argument asserts that the amplifier's measured performance with raw AC power is more indicative of its behavior under the conditions in which it will be used: the customer's home. The latter position holds that since AC power quality varies from location to location, one should measure the amplifier's intrinsic…
A contentious subject is exactly how much of the KSA-250's power delivery is in pure class-A, which is when both "upper" and "lower" sets of output transistors are turned on all the time. By contrast, class-B is when the upper transistors are turned on only during the time the output waveform lies on the positive side of ground potential and the lower transistors only during the time it lies on the negative side of ground. Class-A/B, which applies to the vast majority of solid-state amplifier designs, involves a small standing bias current to ensure…
My second comparison of the Mark Levinson No.23.5 was performed with the obvious head-to-head competitor for the $5900 No.23.5, the $5900 Krell KSA-250. While each ranks among the finest solid-state amplifiers I have used, they still differed significantly in their sonic characters, meaning that a system set up optimally for one would need some adjustment to get the best from the other.
In a nutshell, the Krell was less upfront in its midrange balance than the Levinson, sounding…