I didn't measure the Meze Audio 99 Classics' frequency response; I lack the necessary simulated head and torso, and estimating the optimal response of headphones is far from simple. However, I measured the 99 Classics' impedance and electrical phase with the headphones mounted on my head (fig.1. The electrical phase angle was close to 0° up to 6kHz, suggesting that the drive-unit behaves as a pure resistor up to that frequency; the slightly positive angle that increases above 6kHz is due to the driver's residual inductance. The impedance magnitude was a fairly…
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I have reviewed several network-connected music servers in recent years, from Antipodes, Aurender, and NAD. All performed well but are relatively expensive, and their associated player apps didn't equal Roon's user friendliness in terms of interface, organization of the library, and inclusion and updating of metadata. So when Roon Labs introduced their own server, the Nucleus+, I first reviewed and then purchased it, along with a lifetime subscription to Roon. But at $2498 without an internal drive for storing music files, the Nucleus+ is still relatively expensive, and even Roon's less-…
Pro-Jecting
The Pro-Ject Play app's home screen offers buttons for selecting Music Library, Web Radio, Bluetooth, USB/PC (echoing the function of the Stream Box's front-panel button), and Shairport-Sync. Selecting Bluetooth and pairing with my iPhone 6S let me stream music without any problem. Selecting Music Library brings up the usual menu of Favorites, Playlists, Artists, Albums, and Genres, as well as buttons for Media Servers and Internal. Selecting a track to play and then pressing Playback at the bottom of the screen displays the total playing time and elapsed time, as well as…
The Pro-Ject Play app's home screen offers buttons for selecting Music Library, Web Radio, Bluetooth, USB/PC (echoing the function of the Stream Box's front-panel button), and Shairport-Sync. Selecting Bluetooth and pairing with my iPhone 6S let me stream music without any problem. Selecting Music Library brings up the usual menu of Favorites, Playlists, Artists, Albums, and Genres, as well as buttons for Media Servers and Internal. Selecting a track to play and then pressing Playback at the bottom of the screen displays the total playing time and elapsed time, as well as…
Sidebar 1: Specifications
Description: High-resolution, multi-room (up to 6 devices) network bridge controllable via Pro-Ject Play iOS app, Web browser, Roon. Input ports: 2 USB A, Micro USB B (PC-Detox), Network (Ethernet, WiFi), Bluetooth. Outputs: Audio-optimized USB A, HDMI (video). Audio formats supported: PCM up to 32-bit/352.8kHz, DSD256. Internet Radio: Shoutcast. Streaming Services: Spotify, Tidal. Supported data protocols: DLNA, RAAT, Shairport. Outboard power supply (included): 18V/1A DC.
Dimensions: 4.1" (103mm) W by 1.4" (36mm) H by 4.1" (103mm) D. Weight: 0.83 lb (375gm…
Sidebar 2: Associated Equipment
Digital Sources: Roon Nucleus+ media server, iPhone 6S, iPad mini running Roon 1.6 & Pro-Ject Play apps; dCS Rossini, PS Audio DirectStream, Pro-Ject Pre Box S2 Digital D/A processors.
Power Amplifiers: Lamm M1.2 Reference monoblocks.
Loudspeakers: Joseph Audio Perspective2, KEF LS50.
Headphones: Audeze LCD-X.
Cables: Digital: AudioQuest Vodka (Ethernet); AudioQuest Diamond (USB). Interconnect: AudioQuest Wild Blue (balanced). Speaker: AudioQuest K2, Cardas. AC: AudioQuest Dragon Source & High Current, manufacturers' own.
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For those who listen with their ears and not their brain, perfectionist hi-fi offers many surprises.
A friend called me up a few weeks ago and asked if the DAC we both own had received an automatic firmware update he hadn't heard about; something had changed, it wasn't good, and he couldn't figure out what it was. His system's sound was suddenly pale and unfocused.
There had been no firmware update.
The next morning, he called me again. He'd remembered that, earlier the day before, he'd swapped out a meter or so of the standard Ethernet cable connecting his network switch…
For those who don't explode their preamplifiers with audiophile aftermarket fuses, the XP-22 is warranted for is three years, assuming you buy from an authorized dealer, though Pass Labs has a reputation for aggressively supporting its products well past the warranty period. "[W]e service everything we have ever built, usually for free," Colburn told me. "Some of the work on old stuff costs some money, but it's pretty cheap—and a smile is usually good for a discount."
Listening: the ghost in the machine
First, some quasi-objective observations. The XP-22, I noticed, has rather low…
Sidebar 1: Specifications
Description: Solid-state stereo preamplifier with remote control and separate power supply. Inputs: 3 single-ended (RCA), 2 balanced (XLR), 1 single-ended tape (RCA). Outputs: 1 single-ended line-level (RCA), 1 line-level balanced (XLR), 1 tape (RCA). Input impedance: 22k ohms, all inputs. Output impedance: balanced, 50 ohms; single-ended, 25 ohms. Maximum output: 33V RMS. Frequency response: 10Hz–20kHz, ±0.05dB; –2dB at 159kHz. Crosstalk: >100dB. Total harmonic distortion: <0.001 at 1V, 1kHz. Residual noise: 2uV RMS for signal/noise of 125dB ref. max out…
Sidebar 2: Associated Equipment
Analog Sources: Thorens TD 124 turntable (reconditioned by Schopper AG); Ortofon RMG-212 (rebuilt), Thomas Schick 12" tonearms; Ortofon 90th Anniversary SPU & Xpression cartridges.
Digital Sources: Intel NUC computer with SSD drive running Roon Optimized Core Kit; PS Audio DirectStream DAC.
Preamplification: Auditorium 23 Standard step-up transformer, EAR 834P phono stage, PS Audio BHK Signature preamplifier.
Power Amplifiers: PS Audio BHK Signature 300 Mono, Pass Laboratories XA60.8 (all monoblocks).
Integrated Amplifier: Leben Hi-Fi…
Sidebar 3: Measurements
I measured the Pass Laboratories XP-22's performance with my Audio Precision SYS2722 system (see the January 2008 "As We See It"). The maximum gain was the specified 9.5dB for the balanced inputs to the balanced outputs, but 6.07dB from the unbalanced input to the unbalanced output, the latter result 3dB higher than the specified gain. The preamplifier preserved absolute polarity (ie, was non-inverting) with both balanced and unbalanced inputs and outputs. (Its XLR jacks are wired with pin 2 hot, the AES convention.)
The XP-22's unbalanced input impedance…