Tag Archives: Amplifiers

Burning Amp Festival 2021 Set for Oct. 16 & 17

The following is a press release issued by Burning Amp Festival.
San Francisco, CA | July 2021 — An expanded Burning Amp Festival 2021 returns after a year of Covid lockdown, October 16th & 17th at Fort Mason Center on the bay in San Francisco.
This will be the 13th Burning Amp, which has since 2007 provided a forum for Do-It-Yourselfers and audio hobbyists to meet, learn, and show off their projects. It is a two-day event.
Saturday will feature seminars by Bob Cordell and Demian Martin. Bob Cordell is an engineer and author of “Designing Audio Power Amplifiers”.  Demian Martin is an audio product designer and holds numerous patents.
Also Saturday will be a Build Camp (see photo below from 2019’s Burning Amp) of a new amplifier design by Nelson Pass featuring unique devices and a super simple circuit.
Sunday is the main event with DIY’ers showing off their projects in Building C, and presentations in the Firehouse, capped off by an auction and raffle for donated items.
Confirmed for Sunday presentations are Steven Dear on the science behind audio perception, and as always, Nelson Pass updating the “Greedy Boyz” on his latest designs for the DIY community.  Steven Dear is a researcher in audio neurophysiology and perception.  Nelson Pass is well known in the audio industry and his current companies are Pass Labs and FirstWatt.
Check burningampfestival.com for updates and ticketing information.

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Goldmund Telos 590 Nextgen II Integrated Amplifier

Let me be honest. Right up until this very review I haven’t been much of a fan of integrated amplifiers. Cramming a preamp, a power amp, and, nowadays, a digital source component into a single box just never seemed like the wisest engineering choice to me. Not only does doing so greatly increase the risk of electro-mechanical interactions among the three different circuits; it also makes coping with the vastly different power-supply, shielding, and grounding requirements of each component section a much tougher proposition. There are sound reasons (excuse the pun) why most of the manufacturers who make integrated amplifiers also make large stereo and monoblock amplifiers, preamps with outboard (physically and electronically isolated) power supplies, and stand-alone DACs and phonostages (many of them also with outboard power supplies).

Thus, my review of the Goldmund Telos 590 Nextgen II—a 215Wpc (into 8 ohms) Class A/B integrated with built-in 384k/32-bit DAC (no phonostage, alas)—is something of an experiment. Having read in these pages about the strides made in integrated amplification—and having a genuine curiosity about the sonic merits of today’s finest compact components (polar opposites of my sonically incomparable, but also incomparably large, complex, and expensive MBL system)—I decided to take the plunge with a company whose products I’m familiar with and like.

To say that I’m glad I did this would be, perhaps, one of the bigger understatements I’ve committed to print. As you will see, the Telos 590 Nextgen II is a standard-setter. This isn’t to say that I have no reservations about Goldmund’s integrated (I will come to them in due course). What I am saying is that in direct comparison with first-rate separates that, collectively, cost more than four times what the $29,750 Telos 590 Nextgen II costs, the Goldmund unit didn’t just hold its own; it excelled, particularly in the bass and power range (but also, in some respects, in the mids and treble). And it did so without provoking the big reservations about soundstage dimensions, dynamic range and impact, detail retrieval, and noise levels that, in the not-too-distant past, inevitably popped up in reviews of integrated amplifiers.

On the outside, the Telos 590 Nextgen II looks identical to its predecessor, the highly praised Nextgen I—a stout, 45-pound, rectangular aluminum-and-steel box with an LED display in the center of its front panel. The display reads out exactly three metrics: on the left, the number of the input that has been selected (ranging from “1” through “8,” and all stops in between); on the right, the volume level (ranging from “00” to “99”); and dead center, the power status of the unit (a lighted pair of horizontal bars confirms that power is on and the integrated is ready to make music). There are metal knobs on either side of the LED display (two total). Rotating the one on the left changes the input; rotating the one on the right changes the volume. The knobs are relatively lightweight for a unit of this price, and show next-to-no resistance when turned.

Though input and volume adjustments can be made directly via the two front-panel controls, Goldmund also includes a small metal remote, which allows you to do these same things (and several others) via pushbuttons. In addition to changing input and volume level, the remote allows you to mute the preamp (which also turns off the volume light on the right side of the LED panel) or to put the unit in standby mode (which also dims the entire display).

On the back of the Telos 590 Nextgen II are eight inputs and exactly one set of output binding posts for the amp’s left and right channels. Though these posts are said, by Goldmund, to have been structurally improved, they are the first of my very few reservations about the Nextgen II. 

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iFi iPhono 3 Black Label and Chord Electronics Huei Phonostages

In any vinyl-based audio chain, the phonostage is one of the most important components. It takes the teeny, tiny signal from the cartridge and boosts it enough for the preamp and the amp to make sweet music. It’s an extremely sensitive component, doing multiple, insanely important jobs, and I’m picky about my phonostage. Thus, I was very excited to receive two new compact black boxes to play around with, the iFi iPhono 3 Black Label ($999) and the Chord Electronics Huei ($1495).

The iFi iPhono 3 is a long, relatively thin and compact rectangle, with small dipswitches on the bottom. There is no power switch—it remains on at all times. Little green lights glow to let me know it is working. The input connections are at one end of the rectangle, and the outputs at the other. It isn’t the sort of thing I’d keep out on a desk. I love a big shiny silver box, but sometimes it’s nice to declutter. 

The Chord Electronics Huei is also very compact, and it is also black, but it prominently features four glowing lights bumped up along the front with a translucent plastic bit on the top that shows off the guts. While small, the Huei is definitely meant to be shown off. There is a small power switch on the Huei’s back, along with the inputs and outputs, but otherwise it is fairly simple.

Despite their small sizes, both phonostages are incredibly versatile. That is the first thing I look for in a phonostage, especially in this price range—most folks spending $999 or $1499 probably need the ability to run some low-output mc cartridges. Since carts come in all shapes and sizes, most phonostages have multiple loading options to maximize their compatibility. If you only plan on using an mm cartridge or a high-output mc, then great, congratulations, you’re a fully self-actualized human being, who knows exactly what you want forever and will never change, and I’m jealous. But for the rest of us, flexibility is an asset in itself—part of the joy of high-end audio is trying a wide range of equipment, and both of these phonostages will allow for a ton of variation.

Setup was relatively easy, once I understood how the two different phonostages changed their load settings. Starting with the iFi iPhono 3 Black Label, I attached the RCA cables, then plugged it into mains with the iPower X, which was an upgraded power supply and came standard. Easy enough—but next was the slightly complicated part. The bottom of the iPhono is filled with little baby switches and a ton of options. Fortunately, iFi had a super handy online calculator that essentially did all the work after I input my cartridge specs. The iPhono featured loading options from 22 ohms on up to 47k ohms, with six stops between, and either 36, 48, 60, or 72dB of gain. For my Zu DL-103, I chose 60dB of gain with a load of 330 ohms. The online calculator showed me the dipswitch layout and made executing it totally brainless, which is sort of necessary for me, although there is also a physical chart for anyone without access to the website.

Next up, I plugged in the Chord Electronics Huei, fired it up, and took a moment to marvel at the pretty lights. I’m a simple man and I like shiny things. However, the lights did more than make me happy—they were also buttons that changed the settings. Each color corresponded to a different load, and switching between them was as easy as tapping and watching the colors change. A nice, glossy chart explained how it all worked, and I settled on purple for the load, which was 320 ohms, and blue for the gain, which was 60dB. The Huei included a bunch of different gain steps—from 49dB on up to 70dB, with six total stops in between for the mc section, and 21dB on up to 42dB with six stops for the mm section. The impedance can be adjusted from 100 ohms up to 3.7k ohms for mc’s, and is a strict 47k ohms for mm’s. The Chord Electronics also included XLR outputs, which changed the gain slightly, allowing for up to 76dB max with an mc, and 48dB max with an mm. Overall, the Huei was the easier of the two to get set up, and had slightly more loading options—but neither was particularly difficult to use, and both were extremely versatile.

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Parasound Taking the Audio-Show Plunge at RMAF

The following is a press release issued by Parasound.
SAN FRANCISCO (July 12, 2021) — When Parasound introduced and first started shipping its flagship Parasound Halo JC 1+ 450-watt monoblock power amplifier in early 2020, they were looking forward to demonstrating the amps to customers, reviewers, and dealers at the AXPONA 2020 High End Audio show outside Chicago that August, 2020. However, with the rapid spread of Covid 19, that show was not to be.
Now, with the Rocky Mountain International Audio Fest, popularly known as RMAF, opening to the public in October, Parasound will be exhibiting at its first domestic audio show since 2019. The centerpiece of the exhibit will be a pair of the company’s flagship Parasound Halo JC 1+ power amplifiers with a speaker partner to be announced at a later date.
The Parasound Halo JC 1+ is the result of a five-year effort by John Curl and Parasound to replace, after two decades, their legacy Parasound Halo JC 1 with a new amplifier that is noticeably better.
“‘A little better’ wasn’t good enough for me, and it certainly wasn’t for John,” said Richard Schram President and founder. “The improvement had to be noticeable and dramatic. It had to grab the listener’s attention and leave them in a state of amazement. This project encompassed an almost total redesign of the internal circuitry so it can deliver effortless power at 450 watts into 8 ohms, 850 watts into 4 ohms, 1300 watts into 2 ohms, and a peak current of 180 amperes; the JC 1+ excels even with speakers that can dip to 1 ohm. It operates in pure Class A up to 25 Watts and Class AB to full power, reflecting Curl’s attention to detail and sound quality.”
“In 2003, the JC 1 was an immediate success,” said Richard Schram, Parasound’s president. “For over ten years we couldn’t imagine how to improve it. Therefore, I was surprised and excited when John called me in early 2014 to discuss his ideas for a new amplifier that would significantly outperform the JC 1. During 2015 and 2016 we built numerous prototypes to confirm Curl’s theories, and the sonic improvements he’d predicted. The results were outstanding. We decided to create a new amplifier built on the JC 1’s legendary reputation. The JC 1+ is a technological masterpiece, raising the bar for amplifier performance and value for years to come.”
Parasound invites enthusiasts to experience the new Halo JC 1+ amplifiers displayed on NorStone Spider amp stands in room 11-116 at RMAF 2021.
The Parasound Halo JC 1+ power amplifier, in black or silver finish, is currently available from authorized Parasound dealers as well as any of our authorized e-commerce partners.

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Audionet Humboldt Integrated Amplifier

This review feels very much like an opening act, following the headliner.

In the July/August 2020 issue of TAS, Greg Weaver penned a review of the Audionet Stern linestage and Heisenberg monoblocks, declaring the Scientist Series both the reference-level cat’s meow and pure audiophile shizzle (i.e., he liked them very very much). His review was thorough, well conveyed, and left little to add. Now the Humboldt combines technologies from Audionet’s $150k reference electronics into a huge, and hugely ambitious, integrated amplifier—the $55k Humboldt. 

Friedrich Wilhelm Heinrich Alexander Von Humboldt was a Prussian scientist and explorer (1769–1859), who is best known for his analysis and understanding of how plant species are distributed throughout the world. He was a botanist, expert geographer, naturalist, explorer, and polymath. He is considered by some to be the father of ecology, and one of the first great environmentalists. Audionet’s U.S. distributor, Bill Parish of GTT Audio, is none of those things, although I’m pretty sure he has a garden in his backyard. He is, however, a fervent supporter of the company, and has been for many years. I don’t think anyone was more sincerely excited about the Scientist Series introduction than Bill, except maybe Thomas Gessler, Audionet’s International Sales Manager. Thomas’ passion for meticulously crafted audiophile equipment, whose specs settle between untouchable and unmeasurable, is well known in the industry. Audionet’s “Lighthouse” project, begun in 2013, was an all-out assault on what could be achieved, and the obvious first step was a linestage and monoblock amplifier. Enter Stern and Heisenberg. The Humboldt is the logical next step in the model lineup. For those who can’t afford or can’t accommodate separate components, the Humboldt is the solution. I offered Mr. Gessler the opportunity to describe what makes the Humboldt special; his response is unsummarizable. (I am well aware that is not a word, but it wasn’t.)

Thomas responded, “With Stern and Heisenberg, Audionet has attempted to redefine what is possible today in sound and music reproduction without regard to the effort and cost. It was to be another ‘Lighthouse’ project, with which we wanted to tear down the existing boundaries and redefine the sonic horizon. Thus, we spared no expense and effort and invested all our heart and soul. From conception to industrial design, circuit design, electronic components, and materials, we meticulously redesigned, tested, experimented, and validated everything. As a result, we have created pre- and power amplifiers that define the limits in terms of speed, stability, resolution, distortion, and noise, and in most cases are better than the competition by dimensions. Finally, audio does not sound like a machine any more—just pure, free, light, fine, delicate, and authoritative music and listening pleasure. How do you bring this all together in one housing? First of all, by making no compromises with regard to everything that is relevant to sound reproduction. It’s not the dimensions of a power supply, but its construction and its components that make the bigger difference. A smaller power supply will, of course, result in a loss of possible maximum performance. But this is something every customer has to decide for himself—what level of performance is required for him. By reducing the size of the power supplies, we gained a lot of space without any loss of sound quality. We were also able to reduce the size of the pre- and power amplifier boards because of the lower potential power requirements. But, also, without any noticeable loss of sound, because we did not abandon the decisive circuit details nor any components and materials relevant to sonic quality. Humboldt is, therefore, essentially a careful audiophile downscaling in the sense of potential absolute performance, without sacrificing the decisive sonic and technical merits of Stern and Heisenberg! If you want the absolute sonic and performance limit, choose Stern and Heisenberg; if you want the sonic and performance limit of an integrated amplifier, choose Humboldt. Like its big brothers, Humboldt sets the benchmarks of speed, stability, distortion, and noise for integrated amplifiers. And Humboldt also sounds like nothing: pure, free, light, fine, delicate, and authoritative music and listening pleasure. Actually, very simple, but technically, a Herculean task.” 

Audionet Humboldt Integrated Amplifier Rear

The technical details, case design, inputs, and features were well explained in Greg’s review, and do not need to be reiterated as they are nearly identical, other than the obvious reduction in power supply, the single-chassis design, and the subsequent output-power reduction to 320Wpc into 8 ohms, 460Wpc into 4. For most, 320Wpc into 8 ohms is more than sufficient. For more power, look to the Stern/Heisenberg combo, and ye shall be satisfied. There are no DAC or phono modules available. As Bill Parish explained, “The concept of plug-in modules is simply not in conjunction with the level of performance the Humboldt has attained.” The Humboldt is built with the design principles of NASA, the resilience of a Sherman tank, the ease of use demanded by Apple, the aesthetic flair of a Manhattan plastic surgeon, and the engineering prowess of, well, a German engineer. Prächtige Skulptur!

Sonically, Humboldt resembles the atmosphere around Mount Everest. This integrated amp offers clarity, a complete absence of pollution, unrestricted vistas of majesty, the power and speed of an avalanche, and the romance, passion, and intensity of Into Thin Air. (See how I stuck with the Everest theme there?) The noise floor is also perceived like the “are they even there?” distant plains of Nepal as seen from Everest’s summit, 29,032 feet below. And like the wonder Everest is, the Humboldt’s presentation is natural in its truest form: smooth and mild-mannered when it needs to be, yet able to rage like Vesuvius. There is a variation and richness of timbre, which I perceived as simply better differentiated, with more palpable and clearer colors than most of what I have heard previously. Low-end extension is simply taut, unrestricted, and visceral without haze or savagery. Layering of the soundstage is on a completely different canvas, as if painted on a mountain wall as opposed to the confines of a typical canvas. The high-frequency reproduction is effortless, while never calling specific attention to itself. I found the midrange to be ever so slightly highlighted in the lower mids on some speakers, although this was imperceptible on others. 

With the finesse of a French painter and the speed and handling of a McLaren 650s, the Humboldt is the fundamental expression of Thomas’ Lighthouse project. In essence, it takes what it is given, amplifies it, and sends it to the speakers without otherwise affecting the signal in any perceivable way. Imagine, if you will, watching water from a crystal-clear mountain spring silently fall off the edge of a great waterfall, plunging faster and faster. down thousands of feet to a cool blue lake below. The water is imbued with the energy that gravity exerts upon it; yet, the water itself remains completely pure, untouched, and unchanged. A “gravity amplifier,” as it were.

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Rockwell Amplifier by ampsandsound

For the last five weeks, I have had the opportunity to sit back and enjoy one of the best amplifiers I have heard in a long time. It all started when I got a phone call from the owner of ampsandsound, he said he had something new and special in the works. I was intrigued,... Read More »

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Gryphon Audio Designs Antileon EVO Stereo Power Amplifier

Audio components come and go over the years, but a few designs are so fundamentally correct from their inception that the product’s basic architecture cannot be improved upon. A prime example is the Antileon power amplifier from Gryphon Audio Systems of Denmark. Introduced in 1995, the amplifier is now in a third iteration—the Antileon EVO, reviewed here. Although it features upgraded parts and a few new design tweaks, the Antileon EVO’s fundamental DNA remains the same

That DNA is like a blueprint for creating a no-compromise stereo power amplifier: pure Class A operation, an absolutely unflappable power supply, an overkill output stage, and massive heatsinks. Add completely independent left and right channels (including transformers and power cords), very little negative feedback, balanced circuitry, fully discrete components throughout with no coupling capacitors, and lavish execution with spectacular metalwork and industrial design, and you have the foundation of an amplifier with potentially reference-class performance. All the basic design elements of the original Antileon are here in the EVO, but taken to the next level of execution. 

The Antileon EVO is the very definition of a dreadnought—one look and you know that this amplifier means business. Although rated at 150Wpc into 8 ohms, the Antileon’s size, weight, and construction suggest an amplifier of five times that power output. But as we’ll see, such large hardware is required to ensure that the amplifier delivers its rated power in Class A operation.

Gryphon Audio Antileon EVO Stereo Power Amplifier Rear Panel

Before delving into the Antileon EVO, a little history is in order. Gryphon Audio Systems was founded in 1985 by Flemming Rasmussen, in the same way that many of the best high-end companies started—with the founder building a one-off, no-compromise component for his own use. In Rasmussen’s case, he created a phono preamplifier so that he could better hear exactly how the various phono cartridges he distributed sounded. When a Japanese distributor heard this phono- stage in a CES demo, he immediately asked Rasmussen to build a second unit for him. Unbeknownst to Rasmussen, the distributor loaned the phonostage to Japan’s prestigious Stereo Sound magazine, which promptly awarded the Headamp, as it was called, its highest honor. Gryphon Audio Designs was in business. 

Thirty-six years later, Gryphon is a major manufacturer of a full line of electronics, sources, loudspeakers, and cables. Yet the mindset with which the company was started—building components without commercial constraint—is still alive and well. Although not that renowned in North America, the marque is revered in Europe and Asia. My only previous experience with Gryphon (other than at shows) was an exceptional one. In 2012, I visited Andy Payor of Rockport Technologies to learn more about how he designs and builds speakers (see my review of Rockport’s Altair in Issue 214). In his spectacular custom listening room, Payor played for me his flagship Arakkis loudspeaker, actively tri-amped with all-Gryphon amplification. The sound was transcendent. I wrote a blog about that experience, titled “The Best Stereo System I’ve Ever Heard,” which is exactly what it was at that time. Andy Payor is among a small, very elite group of the world’s top speaker designers who scour the planet for the best-sounding amplification. That he would choose Gryphon to demonstrate his flagship speaks volumes.

The Antileon EVO makes quite a visual statement apart from its sheer muscular bulk. The front panel eschews the typical flat faceplate in favor of polished black-acrylic panels flanking a hemispherical ribbed column. The polished acrylic adds a touch of elegance. A large sub-panel, partially recessed into the acrylic side panels, contains a row of buttons and a display. The left-most button turns the amplifier on and off. Turning the amplifier on automatically launches an elaborate test routine that checks the amplifier’s operating conditions before full power-up. This procedure is accompanied by flashing red indicators in the subpanel. After a few seconds, the test indicators go dark and the amplifier is ready for action. You can also manually run the diagnostic program by pressing a front-panel button. 

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Orchard Audio Introduces Starkrimson Stereo Ultra

The following is a press release issued by Starkrimson.

June 15, 2021 | Succasunna, New Jersey –  Following the enormous success of the Starkrimson® Mono amplifier, Orchard Audio is introducing the Starkrimson Stereo Ultra amplifier, with the same proprietary dual-feedback modulator and next-generation gallium nitride (GaN) transistors. Unlike its predicesor the Ultra amplifier delivers up to 500WRMS (1000WPEAK) of power and 20A of current while maintaining extremely low noise and distortion.

This latest design, which has already been previewed, tested and highly praised by those who were able to have access to it, fully explores the benefits of the latest GaN transistors, providing less harshness, cleaner highs, and better overall transparency and detail with irrelevant noise levels. The pulse-width modulation is performed completely in the analog domain before being amplified by the GaN power stages. Starkrimson amplifiers use Leo Ayzenshtat’s proprietary DC-coupled, fully balanced dual feedback modulator, which allows the amplifier to be completely balanced from input to output, through the use of bridged GaN power stages.

This design provides the Starkrimson Stereo Ultra amplifiers with a huge reserve of power for extended transients, and the power expands linearly with the load – 125 watts into 16 ohms; 250 watts into 8 ohms; and 500 watts into 4 ohms – for powerful, unrestrained music. The amplifier is packaged in an aluminum and steel chassis with high-end gold-plated binding posts and connectors, with a front panel option of either matte black or brushed aluminum (silver).

Features:

  • Fully balanced from input to output (w/differential input)
  • Differential and single-ended audio inputs
  • Extremely low noise and distortion
  • 2-ohm capable
  • 20A of output current

 

Specifications:

  • Signal-to-Noise Ratio (SNR): 120dB (A-weighted, 22kHz BW)
  • Frequency response: DC – 80kHz+
  • Gain (balanced input): 19.05dB
  • Gain (single-ended input): 25.05dB
  • Power output into 16/8/4Ω: 125/250/500WRMS

 

Orchard Audio is still offering preorder prices ($1,999.95 USD) on its website until the end of June 2021. Starkrimson Stereo Ultra amplifiers will start shipping in August and are available with differential (XLR) and single-ended (RCA) inputs or both ($150 option). All DIY enthusiasts can also order the Starkrimson Ultra Mono Amp Module and kits separately, in order to build their own systems.

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The Triode Lab 45 EVO Single-Ended-Triode Integrated Amplifier: The Evolution of the First Watt!

Back in October of 2020 I did a straw poll among readers of Jeff's Place and Positive Feedback to find out what audio products they would be most interested in having me write about. The most popular and intriguing request among readers was the artisanal and custom-made Triode Lab 2A3 EVO single-ended-triode integrated amplifier from... Read More »

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First Watt F8 Stereo Power Amplifier

By my count the F8 represents the sixteenth First Watt power amp authored by the undeniably prolific Nelson Pass. Each unit has been a unique creation said to be “best” in some particular way, though they all happen to look similar because they use the same basic chassis and power transformer. The F8 represents a variation on the popular J2. Its origins go back to 2015, when Nelson had the notion to create a design similar to the J2, based on the SemiSouth Silicon-Carbide R100 power JFET, but using an alternative front-end gain stage. The prototype, says Nelson, was a clear improvement, but because of the J2’s popularity the decision was made to wait. After some additional work over the past six years, that alternative design was finally released as the F8. It is a stereo single-ended Class A amplifier with only two gain-stage devices per channel, a single Toshiba 2SJ74 JFET input, and the SiC R100 power JFET output. Both of these transistors are no longer in production, but available in limited quantities from the First Watt new-old-stock “vault.”      

Circuit-wise, the F8 is quite similar to the J2 amplifier with a virtually identical output stage. However, only one front-end transistor is used instead of six, and it is operated as a current-feedback amplifier as opposed to the J2’s voltage-feedback design. One consequence is reduced gain (only 15dB), but according to Nelson, a simpler front end is more consistent with the single-ended approach to amplifier design and pays off in a purer second-harmonic character, less distortion with lower negative feedback, greater bandwidth, and a higher damping factor. Specifically, comparing the published specs for the J2 and F8, it’s clear that the F8’s damping factor and high-frequency response are twice as good, and that its THD is 0.02% versus the J2’s 0.03%. Unlike the J2, the F8 does not have a balanced input. It also incorporates AC output-coupling in the form of two large electrolytics (10,000µF each) in parallel, bypassed by one polypropylene cap, to eliminate any DC at the output. The resultant bass roll-off frequency is 1Hz. 

Power output is similar, as well. Keep in mind that this is a low-power amplifier, 25Wpc into an 8-ohm load and half that into a 4-ohm load. As such it needs to be carefully matched with a compatible speaker. An 8-ohm speaker with a minimum sensitivity of 90dB would be ideal. The Fleetwood DeVille that I grew quite fond of this past year (and reviewed in Issue 309) was used for all the listening tests. It certainly meets the requirements and offers a sensitivity of 94dB, to boot. The F8’s power dissipation is 170 watts to produce an output of 25Wpc, which means quite a bit of waste heat. Be sure to allow plenty of ventilation around the chassis. Even so, it runs fairly hot to the touch after about an hour of being powered up.

first watt f8 rear

So what does it sound like? Well, it turned out to be the sonic equivalent of Reyka, an Icelandic vodka that has been said to taste dangerously close to fresh water. The F8 started off much like a tabula rasa, a clean slate, distinguished by the absence of inherent sonic colorations. It didn’t sound bright or warm, but consistently took on the flavor of whatever front end I threw at it. That’s not to say that it didn’t have its own sonic imprint. To my way of thinking, what it did right was a logical consequence of a confluence of three factors: simple single-ended circuit topology, wide bandwidth, and an excellent damping factor. 

The resultant airy treble, tonal purity, and superb transient speed were instantly endearing. So was its startling soundstage transparency. It shouldn’t come as a surprise when I tell you that my favorite matching preamp was of the vacuum-tube variety. The F8 allowed tube virtues such as a deep and layered soundstage to shine through, while maintaining an authoritative midbass. Tympani strikes were staggering; drum kits were persuasively resolved with satisfying kick-drum crunch; and brush work was delicate. It was like having your cake and eating it, too. The upper bass and lower midrange weren’t shabby, either. On my favorite performance of the Dvorˇák Cello Concerto in B Minor, with Jacqueline du Pré and the Chicago Symphony Orchestra conducted by Daniel Barenboim [EMI CDC-7476142], the loving collaboration of soloist and orchestra shone with emotional intensity and uncommon clarity. 

When it came to macrodynamics, 99% of the time I didn’t feel that I was missing anything. On a rare occasion, on highly dynamic material, there was a hint of compression. But most of the time the F8 didn’t sound at all like a low-power amp. It managed to project plenty of authority through the power range of the orchestra. Coupled with its robust boogie factor, it was able to extract the music’s dramatic content with total conviction.

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