I switch back and forth between a Fisher 800-C receiver and a Sherwood S-5500 II amplifier. My sources are: a KAB-modified Technics SL-1200 Mk. 2 with an Audio Technica AT440MLa cartridge on a Technics headshell, and an iPhone 6 or MacBook Pro through an AudioQuest Golden Gate interconnect (RCA to 3.5mm). These connect to Rogers LS3/5A speakers atop Skylan speaker stands via AudioQuest Type 4 speaker cables.
The TDL speakers was positioned for the best sound (with only one pair of loudspeakers in the listening room at a time), generally some 4' from the rear wall (which is faced with books and LPs) and approximately 5' from the side walls (which also have bookshelves covering some of their surfaces).
Source components consisted of a Revox A77 to play my own and others' 15ips master tapes, a Linn Sondek/Ekos/Troika setup sitting on a Sound Organisation table to play LPs, and Kinergetics KCD-40 and Proceed CD players. Amplification consisted of a Mark Levinson…
Looking first at the Studio 1's impedance, measured using the magazine's Audio Precision System One (fig.1), this suggests that the speaker is an easy load to drive, only nearing 6 ohms in the upper bass. The port/line tuning lies at 30Hz, indicated by the minimum at that frequency. Note, however, the glitch in impedance around 130Hz, which the phase response (dashed line) suggests is due to a resonance, presumably due to the transmission line, and which could correlate with my feelings about a "lumpy" response in this region.
Fig.1 TDL Studio…
Description: Two-way, transmission-line loudspeaker. Drive-units: 1", ferrofluid-cooled, metal-dome tweeter, 6.5" plastic-cone woofer with vented poles. Crossover frequency: 3kHz. Crossover slopes: first-order, high-pass; second-order, low-pass. Frequency range: 28Hz$n20kHz. Sensitivity: 86dB/W/m. Nominal impedance: 8 ohms. Amplifier requirements: greater than 30W.
Dimensions: 28.5" (724mm) H (32.5", 824mm, on stands) by 9" (230mm) W by 13.2" (335mm) D. Weight: 39.5 lbs (18kg) each.
Finishes available: walnut veneer or black, with a brown grille cloth.…
When Herb Reichert reviewed this elegant, stand-mounted, two-way speaker (footnote 1) in the April 2017 issue, he had a hard time optimizing its low-frequency balance in his room. Using PrimaLuna's ProLogue Premium 35Wpc tube amplifier, he eventually got the Contour 20 to sing, and concluded that "The Dynaudio Contour 20 is the first speaker I've heard that might actually be as neutral (I hate that word) as the best headphones. . . . It leaned a touch more toward the left side of my brain than I prefer, but not…
We thought we had heard virtual perfection in power amplifiers before. The SAE Mark II, for instance, produced such beautifully lucid, effortless sound that we honestly believed further improvement would be superfluous. It isn't.
By comparison, the DC…
Description: Solid-state stereo power amplifier. Rated power: 100Wpc into 16 ohms (23dBW), 150Wpc into 8 ohms (21.8dBW), 250Wpc into 4 ohms (21dBW), all at <0.1% IM distortion. Frequency response: DC–20kHz, ±0.1dB; DC–100kHz ±0.6dB. IM distortion: <0.1%, 10mW–150W into 8 ohms; typically below 0.05%. Input sensitivity: 1.75V in for rated power out.
Dimensions: 7" (178mm) H by 9¾" (229mm) D by 19" (483mm) W (standard rack-mount panel). Weight: 40 lbs (18.2kg).
Price: $795 (1970); no longer available (2017).
Manufacturer: Crown International,…
Description: Two-way, dynamic bookshelf loudspeaker with aperiodic woofer loading. Impedance: 8 ohms. Power ratings: minimum amplifier 15Wpc continuous sinewave watts; maximum 70W program.
Dimensions: 11½ (280mm) H by 9¾ (229mm) W by 10" (254mm) D.
Price: $159.90/pair (1969); no longer available (2017).
Manufacturer: Dynaco, Inc., Philadelphia, PA 19121 (1969); company no longer in existence (2017).