Sidebar 3: Measurements
I tested the Bluesound Powernode with my Audio Precision SYS2722 system, then repeated some tests with the magazine's more recent APx500 system. I connected the Powernode to my network and controlled it with the Bluesound app on my iPad mini. (When I first connected the amplifier, it updated its BluOS firmware to v3.16.7.) I used the app's "Customize Inputs" screen to disable "A/V mode" on the inputs with which I was going to do the testing, as this is said to be best for audio-only sources.
As the amplifier has a class-D output stage, I inserted an Audio…
Although I retired as Stereophile's editor-in-chief at the end of March 2019, I still have an ongoing connection with the magazine. As well as contributing reviews and measuring the audio products that are being reviewed, I prepare the magazine's content for republishing on its website. So when JansZen Audio's David Janszen contacted me about reviewing his Valentina P8 loudspeaker, I looked through my back issues to find reviews of JansZen speakers that could be posted. The earliest review I found was by Stereophile founder J. Gordon Holt, of the JansZen Z-600, in December 1966, which you…
According to the manual, the speakers should be positioned with the rearmost corners between 24" and 32" from the wall behind them—but no more because the P8 is designed to rely on wall reinforcement for optimal low-frequency performance. Unfortunately, such close placement was not possible in my room due to a short flight of stairs to the vestibule behind the right speaker. I ended up with the rear corners of the Valentinas 67" from the wall behind them, which meant that I should compensate by switching the woofers to the +3dB level setting. However, when I did so, the upper midrange…
Sidebar 1: Specifications
Description: 2.5-way, floorstanding loudspeaker with sealed enclosure. Drive units: two 7" (180mm) W × 8" (200mm) H electrostatic panels mounted one above the other; two 8" (225mm) alloy-cone woofers; 1" (25.4mm), silk-dome auxiliary "airLayer" tweeter. Crossover frequencies: 500Hz, woofers–electrostatic panels; 5kHz, 1.5-way electrostatic panels. Crossover slopes: first order, 6dB/octave; the airLayer tweeter rolls off with a critically damped, second-order slope below 2kHz, with no upper rolloff. Frequency response: 30Hz–20kHz ±3dB in-room. Nominal impedance…
Sidebar 2: Associated Equipment
Analog source: Linn Sondek LP12 turntable with Lingo power supply, Linn Ekos tonearm, Linn Arkiv B cartridge, Channel D Seta L phono preamplifier.
Digital sources: Roon Nucleus+ file server; Ayre Acoustics C-5xeMP universal player; MBL N31 CD player/DAC; Ayre Acoustics QA-9 A/D converter.
Power amplifiers: Parasound Halo JC 1+ monoblocks, Luxman M-10X.
Loudspeakers: Bowers & Wilkins 804 D4, GoldenEar BRX.
Cables: Digital: AudioQuest Vodka (Ethernet), AudioQuest Coffee (USB), DH Labs (1m, AES/EBU). Interconnect: AudioQuest Wild Blue (…
Sidebar 3: Measurements
I used DRA Labs' MLSSA system, a calibrated DPA 4006 microphone, and an Earthworks microphone preamplifier to measure the JansZen Valentina P8's frequency response in the farfield. I used an Earthworks QTC-40 mike for the nearfield and in-room responses. My primary axis for the measurements was at 90° from the center of the electrostatic panel on the angled front baffle at a distance of 50". (I refer to this as the "normal" axis.) I raised the loudspeaker as far as possible from the floor, but the reflection of the lower woofer's output from the floor meant that I…
Two years ago, Dan Roemer founded Perlisten loudspeakers. Just one year later, when the company went public, their inventory already included 25 different speaker models. I don't know about you, but I find that an astounding achievement.
When Kal Rubinson reviewed Perlisten's flagship floorstander, the S7t, in the December 2021 review of Stereophile, he praised its ability to sort out "perplexing" details on recordings, and wrote, "The dynamic capabilities of the S7t's exceeded anything that I've heard before in this room... Overall, the Perlisten S7t is the best speaker I've heard in…
CH Precision made a move equally smart and enlightening. Rather than devote endless minutes to introducing the new CH Precision C1.2 DAC/Controller, they harnessed many of their finest components together for a demo, which Jim Austin attended at a different time, in which Kevin Wolff compared the sound of various silver disc formats. Thanks to the wise music choices of Kevin Wolff and Roy Gregory, it was time well-spent.
First, however, a few words on the C1.2 DAC/Controller. Due September 1, it's available either in a stereo version that includes one HD digital input card ($36,000), or…
Though a wild goose chase on the hottest day of Munich High End led me to AVM's across-the-street press conference just in time to discover that my only option was to stand in the doorway and sweat buckets or visit their MOC display later in the day, I eventually managed to photograph the innards of the new high-performance AVM CS 8.3 All-in-One (above). This baby offers Wi-Fi and network streaming with a CD player, DAC, class-A headphone amp, and a 250Wpc stereo amplifier. The quad DAC processes PCM up to PCM 32/384 and DSD128. Digital inputs include asynchronous USB and S/PDIF in/out with…
When I reviewed the Moonriver 404 Reference integrated amplifier in the February 2021 issue, I noted that the then-recent fire in the AKM factory in Japan had left the company without chips for the unit's optional DAC. A year later, that issue has been resolved.
A visit with company founder George Polychronidis at the Moonriver display in the MOC's expo halls revealed the 404's two versions of the company's new optional DAC. Because the integrated has a sole digital input, one must choose between the S/PDIF version (approx. $600–$700) and that for USB input (approx. $700–$800). Both use…
