Comparisons: HCA-2
PS Audio's HCA-…
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Although PS Audio insists that the GCC-100 is not an integrated amplifier, it has an Auxiliary line-level output—just like an integrated. The Auxiliary output can be used to drive another power amp, connecting the speaker cables to that amp rather than to the GCC-100, in which case the GCC-100 functions essentially as a line-level preamp. (Leaving the output/amp section of the GCC-100 without a speaker load is apparently not a problem.) I used this connection to compare the GCC-100's output/amplifier section with two other amplifiers I had on hand.
Sidebar 1: Specifications
Description: Solid-state, variable-gain, integrated amplifier with class-D output stage. Maximum output power: 100Wpc into 8 ohms (20dBW), 200Wpc into 4 ohms (20dBW). Frequency response: 10Hz–20kHz, ±0.1dB. THD: <0.02% at 1W, <0.03% at 100W. Input sensitivity: 1.25V. Input impedance: 47.5k ohms. Adjustable gain: 31–41dB (RCA), 37–47dB (XLR). Power consumption at idle: <40W.
Dimensions: 17.25" (440mm) W by 4" (100mm) H by 14" (360mm) D. Weight: 26 lbs (11.8kg).
Serial Number Of Unit Reviewed: A1-5A025 (auditioning), OC-A7-5F002 (measuring).
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Sidebar 2: Associated Equipment
Analog Source: Fully updated Linn LP12 turntable, Linn Ittok tonearm, AudioQuest AQ-7000nsx cartridge.
Digital Source: PS Audio Lambda II CD transport; Perpetual Technologies P-1A, ModWright P-3A digital processors.
Preamplification: PS Audio GCPH phono preamplifier.
Power Amplifiers: Audiopax 88SE monoblocks, PS Audio HCA-2.
Loudspeakers: Avantgarde Acoustic Uno 3.0, Paradigm Reference Studio/100 v.3.
Cables: Digital: Mystic Reference I2S, Illuminati Orchid AES/EBU. Interconnect: Nordost Quattro Fils, Nordost Valhalla, AudioQuest Sky, PS…
Sidebar 3: Measurements
As set up, the sample of the PS Audio GCC-100 I was sent for measurement had a maximum gain of 42dB into 8 ohms for both balanced and unbalanced input signals. Both inputs were noninverting (ie, preserved absolute polarity), the XLR jacks apparently wired with pin 2 hot. The unbalanced input impedance was a high 50k ohms over most of the audioband, dropping slightly but inconsequentially to 32k ohms at 20kHz. The balanced input impedance was 100k ohms across the band.
The output impedance was a moderately low 0.15 ohm at low and midrange frequencies.…
I haven't been shy in these pages regarding my love for the Mission 731i loudspeaker (reviewed in November 1996, Vol.19 No.11). It quickly became my reference standard for an entry-level audiophile speaker. Subsequent to my review, Mission significantly improved the speaker by introducing a silk-dome tweeter (see Follow-Up in April 1998, Vol.12 No.4). I bought three pairs: one for my home recording studio, one for my faux outdoor summer-home system (guest bedroom windowsills, pointing outward), and one for portable use to drag to friends' parties when their sound systems are not up to snuff…
The m71 deviated from tonal neutrality only in the lower high frequencies. A slight highlighting of this range manifested itself in different ways, depending on the recording. On the Ian recording, her voice was a bit more sibilant than I'm used to, and the electric guitar had a bit more bite. On Kohjiba's The Transmigration of the Soul, from Stereophile's Festival CD (Stereophile STPH007-2), the marimba seemed natural but a bit more prominent in the mix than I've heard through other speakers. On some recordings, the highlighted upper frequencies actually enhanced my enjoyment of the work—…
Sidebar 1: Specifications
Description: Two-way reflex-loaded, stand-mounted loudspeaker. Drive-units: 1" Micro-Fiber soft-dome tweeter, 5.25" bonded woven-glass-cone woofer. Crossover frequency: 2.8kHz. Frequency response: 65Hz-20kHz, ±3dB. Sensitivity: 88dB/W/m. Nominal impedance: not specified.
Dimensions: 11 1/2" (296mm) H by 6 5/8" (170mm) W by 10 3/4" (275mm) D. Weight: 10 lbs (4.5kg).
Finishes: Graphite Black, European Beech.
Serial numbers of units reviewed: 207100780 & 1.
Price: $250/pair; Mission Stance stands, $200/pair. Approximate number of dealers: Not…
Sidebar 2: Associated Equipment
Analog sources: VPI TNT Mk.IV, Rega Planar 3 turntables; Immedia, Syrinx PU-3 tonearms; Koetsu Urushi, Clearaudio Aurum Beta S cartridges.
Digital sources: California Audio Labs Icon Mk.II Power Boss, Creek CD53 Mk.II CD players.
Preamplification: Vendetta Research SCP-2D phono stage, Audible Illusions Modulus L1 line stage.
Power amplifier: Audio Research VT100 Mk.II.
Integrated amplifiers: Creek 5350SE, JoLida JD-101A.
Cables: Interconnect: MIT MI-350 CVTwin Terminator, MIT MI-330SG, MIT Terminator 2. Speaker: Acarian Systems Black…
Sidebar 3: Measurements
The little Mission m71 is quite sensitive, 2.83V raising a B-weighted SPL of 88.5dB(B) at 1m. It is also moderately easy to drive, with an impedance (fig.1) that drops to just below 4 ohms in the lower midrange and an electrical phase angle that exceeds 30 degrees only when the impedance magnitude is fairly high. The saddle at 58Hz in the magnitude trace indicates the tuning of the rear-facing port.
Fig.1 Mission m71, electrical impedance (solid) and phase (dashed). (2 ohms/vertical div.)
Although it won't be seen at the scale this graph…
The crossover appears to use symmetrical second-order acoustic slopes, and the woofer's out-of-band behavior is well-controlled. There is a lack of midrange energy apparent, and perhaps a very slight rising trend in the treble—BJR said that "A slight highlighting of this range manifested itself in different ways, depending on the recording." Although the treble rise is balanced by a similar rise in the upper bass, it should be noted that this is almost entirely due to the nearfield measurement technique's assumption of a half-sphere acoustic environment. The m71's -6dB point compared with…