Steve visited my place in Brooklyn just before the New Year, and we…
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Occasional Stereophile contributor Steve Guttenberg publishes a YouTube channel about audio that has achieved an impressive reach. As Steve told me in a conversation I had with him last December, 22% of his 98,000 subscribers (at the time we talked) are under 34 years old, and, to judge from the comments, most of them don't read Stereophile!!!! "It would nice to introduce you to them!" said Steve, and proposed he interview me and post the video to his channel when it hit the magic 100k number, which it did on January 9.
Only recently did I learn that successive generations of the Chevrolet Corvette are referred to by the cognoscenti with two-character alpha-numeric identifiers: C1, C2, C3, and so on. I learned this while reading about the most recent version—C8, known to non-cognoscenti as the 2020 Corvette—which happens to be the first version since C2 that impresses me. (I say that as one who used to work for the owner of a C3, a then-middle-aged male who actually boasted, while under the influence, that he and two of his C3-owning friends drove them solely because their juvenile styling attracted…
But note also, irrespective of the loudspeaker in use: In every listening session I've enjoyed so far, the Cortese has taken at least an hour to warm up—and even then its sound continues to improve over at least another hour. I don't recall another Shindo that has taken as long to perform at its best, and that leads me to guess that this sample still has a while to go before it is fully broken in. Which is kind of fun, really.
And note that other Shindo setup tricks to which I've alluded in the past hold true here. In particular, also like all Shindo amps of my acquaintance, it seems…
I thought I knew what a preamp could do. But when the Dan D'Agostino Master Audio Systems Momentum HD preamplifier ($40,000) arrived for review, all my expectations flew out the window.
The two-piece Momentum HD preamp wasn't exactly a stranger. I'd heard it in two of the finest sounding systems I have ever encountered, at a March 2019 event at Seattle's Definitive Audio and, a month later, at Chicago's 2019 AXPONA. Both systems included Wilson Audio Specialties' Alexx loudspeakers and Subsonic subs; D'Agostino Relentless monoblock amplifiers paired with the Momentum HD preamp (and other…
Switching between all those pieces of equipment while keeping power cables and interconnects separate, ensuring optimal setup consistency, and taking coherent notes is not for the faint of heart. A touch of madness helps. Some may be tempted to resort to mood stabilizers or out-of-body escape when they realize that, because the Momentum HD preamp lacks a numeric volume display, it's virtually impossible to match volume levels by sight. There's a reason for the manual's caution: "The dynamic capability of the new Momentum HD Preamplifier is beyond what is normally experienced with other…
Sidebar 1: Specifications
Description: Solid-state, balanced, line preamplifier with separate power supply/base and remote control. Inputs: 6 balanced (XLR). Outputs: 2 balanced (XLR). Control connections: 12V trigger in/out, RS-232. Voltage gain: Selectable, 10.95dB or 26dB. Frequency response: 20Hz–75kHz, ±0dB; 0.1Hz–1MHz, ±0.5dB. Input impedance: 1M ohm. Output impedance: 10 ohms. THD: <0.02%, 20Hz to 20kHz. Signal/ noise: 75dBu, unweighted.
Dimensions: 4.3" (108mm) H × 18" (450mm) W × 12" (300mm) D (preamp); 3" (75mm) H × 11" (275mm) W × 8" (200mm) D (power supply/base).…
Sidebar 2: Associated Equipment
Digital sources: dCS Rossini SACD/CD transport & Rossini DAC & Rossini Clock & Network Bridge; EMM Labs DV2 DAC; Apple 2017 Macbook Pro computer with 2.8 GHz Intel i7, SSD, 16GB RAM; Roon Nucleus+; Linksys routers (2), Small Green Computer Systemoptique optical isolation bundle, TP-Link gigabit Ethernet media converters plus multimode duplex fiberoptic cable (2); Small Green Computer linear power supply & Small Green Computer/ HDPlex four-component 200W linear power supply (2); external hard drives, SSD USB sticks, iPad Pro.
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Sidebar 3: Measurements
I measured the Dan D'Agostino Momentum HD's performance with my Audio Precision SYS2722 system (see the January 2008 "As We See It"), checking some of the measurements with a loaned sample of Audio Precision's top-of-the-line AP555x system. The gain at 1kHz for the balanced inputs to the balanced output with the volume control set to the maximum was 10.85dB for the low-gain setting, which was how JVS auditioned the preamplifier. (Unless indicated otherwise, all the measurements were taken with this gain setting.) Setting the gain to "26" resulted in a gain at 1kHz…
Manufacturer's Comment
Editor: Thank you to JVS for his very thorough and positive review. It is always gratifying to have a design goal be fully realized in a listener's experience. Jason's obvious enthusiasm matched ours when we first heard the new Momentum HD update.
One note: JA's measurements mentioned something we caught before production commenced but was in the early pre-production control code. The operation of the phase button was reversed in the pre-production code, which is what JSV had. All production units have the correct code.—Dan D'Agostino, founder and chief…
Hi-Fi: The History of High-End Audio Design, by Gideon Schwartz, Phaidon Press, 2019. 272pp. $84.97, hard cover.
The ongoing evolution of hi-fi can be measured in any number of ways. Most obviously, we see that evolution in the technologies associated with our industry: in big breakthroughs—mono to stereo, tubes to transistors, analog to digital—as well as incremental improvements in materials and manufacturing techniques. Those and other refinements bring with them changes in sound quality—hopefully, but not always, improvements—but no less important to the industry are changes in form…