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The EICO HF-81 was restored by Sam Kim at Sam's Audio Labs, in Montreal, Canada. The work done included replacing the output and filtering capacitors and all out-of-tolerance resistors, rebuilding the volume control, rewiring the undercarriage, and resoldering every connection.

Sam Kim's restorations are not the drop-in-and-solder jobs I'm used to. I've replaced coupling and filter caps in many components but have never taken the time to rewire, resolder, and check out the circuit to determine which values of modern-day parts…

Although it does have 32 and 16 ohm output transformer taps, I measured the EICO HF-81 from its 8 and 4 ohm taps only, feeling that these will be optimal for use with modern speakers such as the mbls PB used for his auditioning. While I like the positive electrical connection terminal strips allow, those on the HF-81 are too close together to accept good spades, such as the Kimbers. I therefore used bare wire wrapped around the screws, but if you do likewise, be careful you don't short the live outputs with stray whiskers of wire.

An unexpected problem…

I guess that's why Wes Phillips was surprised when I indicated a serious interest in auditioning the Ruark Equinox. But recently I've been impressed by a…

Description: Two-way bass-reflex loudspeaker with integral stand. Drive-units: 1" (25mm) dome tweeter, 6.5" (165mm) cone woofer. Crossover frequency: 2.8kHz (seven elements). Frequency response: 45Hz–20kHz, ±3dB. Nominal impedance: 6 ohms. Sensitivity: 87dB/W/m. Amplifier requirements: 25–150W.
Dimensions: 34½" H by 10" W by 13" D, including stands. Weight: 110 lbs each.
Serial number of pair tested: 16084.
Price: $4000/pair (1997); no longer available (2006). Approximate number of dealers: 12–15.
Manufacturer: Ruark Acoustics Ltd., 59 Tailors Court…

I estimated the Ruark's B-weighted sensitivity to specification as 87dB/2.83V/m. Its plot of impedance magnitude and phase (fig.1) reveals it to be a moderately easy load to drive. It only drops below 6 ohms, and then only by a little, in the lower midrange and mid-treble. The "saddle" between the low-frequency impedance peaks reveals the speaker's reflex tuning frequency, a moderate 40Hz.

Fig.1 Ruark Equinox, electrical impedance (solid) and phase (dashed) (2 ohms/vertical div.).

Fig.2 shows the individual responses of the tweeter, woofer…

Oh boy, affordable two-ways—what fun.

But the…

Description: Two-way, bi-wirable, floorstanding, infinite-baffle loudspeaker. Drive-units: 1" (25mm) treated–fabric-dome tweeter, ferrofluid-cooled and -damped; 6.5" (165mm) treated–paper-cone woofer with a pure rubber surround, cast chassis, and high-flux magnet system. Crossover frequency: 2.6kHz. Frequency response: 55Hz–20kHz, ±3dB. Sensitivity: 87dB/W/m. Nominal impedance: 8 ohms. Amplifier requirement: 20–100W.
Dimensions: 8" (190mm) W by 10.5" (260mm) D (at base) by 28" (700mm) H. Weight: 26.5 lbs each.
Serial numbers of units tested: 17483 A/B.
…

Ruark may be an unfamiliar name to many US audiophiles, but Brian O'Rourke has been designing loudspeakers for 25 years—first at Diesis and, since 1986, in partnership with son Alan at Ruark. The elder O'Rourke (Ruark is the old Celtic name from which O'Rourke derives) is a master cabinetmaker and member of the Guild of Master Craftsman; this craftsmanship permeates the construction of all Ruark speakers. Alan brings to the firm his background as a precision engineer, not to mention his musical passion as a professional bassist. This is the second Ruark…

This is a cute speaker. And easy to drive, too, as can be seen from its impedance curves (fig.1). Dropping to just 7 ohms in the midrange and 6.3 ohms in the high treble, with a moderate phase angle above the bass, the Templar will work with low-powered amps, as WP found. The sealed box is tuned to a highish 65Hz—the frequency of the big magnitude peak in the bass—which is about what I expected from the box size. Note the wrinkle at 325Hz, which indicates the presence of a strong cabinet resonance at this frequency. The Big Man didn't hear anything amiss in the…