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Ever since I reviewed PrimaLuna's ProLogue Premium, for the June 2012 issue, it has been the model I would turn to when I wanted a moderately priced integrated amplifier to try with a new speaker. It never disappointed me, and never seemed outclassed, even when the speaker was the MartinLogan Montis ($10,000/pair). At $2399, the ProLogue Premium to me represents the "sweet spot" for systems in the range of $4000–$10,000 or higher. Although its 35Wpc may not be enough for some speakers (depending on the room and personal preference), I never had any such problem, regardless of whether the…
To more systematically examine the sound of the DiaLogue Premium HP, I compared it and the ProLogue at matched levels: <0.1dB difference, measured with a voltmeter at the output terminals, using the 1kHz tone of Stereophile's first Test CD (Stereophile STPH002-2). Both amps had EL34 tubes installed, and the DiaLogue Premium HP was set to ultralinear, to match the ProLogue Premium.
Some audiophiles hold that at higher power you may gain maximum volume but lose some finesse, and that as long as the amplifier is not driven into clipping, the fewer the tubes, the better the sound.…
Sidebar 1: Specifications
Description: Tubed, remote-controlled, stereo integrated amplifier. Tube complement: six 12AU7, eight EL34; KT88 or KT120 tubes also available. Inputs: 5 pairs RCA, 1 pair home-theater bypass. Outputs: 4 & 8 ohms. Subwoofer output: RCA. Headphone output: ¼" stereo jack. Rated output power into 8 ohms, 1% THD: triode mode, 40Wpc (EL34, 16dBW), 42Wpc (KT88, 16.23dBW), 45Wpc (KT120, 16.53dBW); ultralinear mode, 70Wpc (EL34, 18.45dBW), 73Wpc (KT88, 18.63dBW), 85Wpc (KT120, 19.3dBW). Frequency response, ±1dB: 7Hz–65kHz (EL34), 7Hz–70kHz (KT88), 7Hz–75kHz (KT120…
Sidebar 2: Associated Equipment
Digital Source: Ayre Acoustics CX-7eMP CD player.
Preamplifier: Convergent Audio Technology SL-1 Renaissance.
Power Amplifier: McIntosh Labs MC275LE.
Integrated Amplifier: PrimaLuna ProLogue Premium.
Loudspeakers: Focal Aria 936.
Headphones: Grado SR125.
Cables: Interconnect, speaker, AC: Nordost Valhalla 2.
Accessories: PS Audio PerfectWave Power Plant 5, Nordost Sort Kone TC, Furutech RD-2 CD demagnetizer.—Robert Deutsch
Sidebar 3: Measurements
My review sample of the PrimaLuna DiaLogue Premium HP (a different one than that auditioned by Robert Deutsch) was fitted with EL34 output tubes—I made sure that the bias was correctly set for these tubes before performing any testing. After allowing the DiaLogue Premium HP to warm up for an hour or so, I used my Audio Precision SYS2722 system (see the January 2008 "As We See It" and www.ap.com) to examine its measured performance. With 4 and 8 ohm output-transformer taps and the choice of triode (green LED illuminated) or ultralinear (red LED) operation, the…
When I think of Cambridge Audio today, it sits firmly in the category of Value with a capital V. After spending the past decade figuring out how to balance price with performance, to give budding audiophiles entry points to better sound, in 2012 they began pushing the upper end of their value envelope with the Azur 851 series of products, of which the Azur 851D upsampling DAC and digital preamplifier ($1649) is the latest model.
I've enjoyed having one of Cambridge's integrated amps in my office system for years, and the company boasts that the 851 series, designed in the UK and…
I moved on to 1971 and "Baby Blue," from Badfinger's Straight Up (CD, Apple)—the song used to glorious effect in the final scene of the TV series Breaking Bad (a reference to the blue meth that Walt perfected). It begins with that famous crunchy guitar riff, dropping into classic early-'70s rock production: simple and compressed. There are Beatles signs all over this album: the arrangements, the sound, the vocal harmonies, the guests (George Harrison), the label (Apple), the producers (Geoff Emerick, Harrison), the keyboard player (Klaus Voorman).
Still, Badfinger managed to transcend…
Sidebar 1: Specifications
Description: Solid-state D/A processor with volume control and remote control. Digital inputs: S/PDIF, TosLink optical, BNC, AES/EBU, BT100 Bluetooth. USB audio input: USB Type B conforming to Audio profile 1.0 or USB Audio profile 2.0 (user selectable), 1.0 or USB Audio profile 2.0 (user selectable). Analog audio outputs: balanced (XLR), unbalanced (RCA). Headphone output: 1 ¼" (6.35mm); supports 600 ohm headphones, but 300 ohms max recommended. DACs: dual Analog Devices AD1955, 24-bit. Upsampling: Analog Devices Black Fin ADSP-BF532 32-bit DSP performing ATF2…
Sidebar 2: Associated Equipment
Digital Sources: Apple MacBook Pro computer (2.66GHz Intel Core 2 Duo, 4GB RAM, 320GB HDD) running OS 10.6.7, Audirvana Plus, iTunes 11.1.5, Sonic Studio Amarra 2.5, Songbird 1.9.3, XLD; Western Digital NAS Device (2TB); Oppo BDP-103 universal BD player; Meridian (formerly Sooloos) Digital Media System (Control 15, QNAP TS-669 Pro NASApple iPad Air, iPod Touch 1G, iPhone 4S. Digital Processors: Antelope Audio Zodiac Platinum DSD DAC & Voltikus Power Supply, AudioQuest DragonFly USB DAC, Benchmark DAC1 USB & DAC2 HGC, Cambridge Audio DacMagic XS,…
Sidebar 3: Measurements
I measured the Cambridge Audio Azur 851D with my Audio Precision SYS2722 system (see www.ap.com and the January 2008 "As We See It"), using mostly a TosLink connection. To test its performance via USB and Bluetooth, I used my 2012 MacBook Pro running on battery power. Apple's USB Prober utility identified the DAC as "Cambridge Audio USB Audio 2.0" and confirmed that it operated in the sonically optimal isochronous asynchronous mode. The Cambridge's S/PDIF and AES/EBU inputs successfully locked to all sample rates up to 192kHz—including TosLink, which is usually…