Sonic Frontiers Anthem Integrated 1 integrated amplifier

When the person on the street hears the term "high-end audio," they usually think of fancy, feature-laden systems that cost more than most houses. The unfortunate phrase evokes images of a lavish lifestyle replete with expansive Manhattan apartments and rolling country estates.

In reality, "high-end audio" has nothing to do with price, features, or complexity. It simply describes a subset of music-reproduction components designed to convey the musical experience in the most realistic way possible—at any price level. A $500 integrated amplifier designed by sensitive engineers to sound faithful to the music is certainly "high-end," while a $2000 amplifier designed as a commodity without regard for how it sounds is not.

Equipment that is more faithful to the original musical event doesn't just belong in the homes of the wealthy, but in the living rooms of average working people everywhere. The three amplifiers I review this month are all contenders for this real-life goal.

The Sonic Frontiers Anthem Integrated 1: $1295–$1495
Anthem is the name of a new line of all-tube audio products from Sonic Frontiers. According to the Canadian manufacturer, the Anthem mandate is fourfold: 1) a comprehensive product line including a preamplifier, power amp, integrated amp, and CD player; 2) all-tube circuitry; 3) distinctive styling, including a black or silver solid-aluminum extruded faceplate; and 4) a US retail price of less than $1500 per product. In short, Anthem is Sonic Frontiers' line of entry-level products for the tube-loving audiophile on a budget. I suspect that by making tubed products available to first-time high-end audio buyers, Sonic Frontiers hopes to hook them on tube sound for life.

The $1295 Integrated 1 is handsome, large, and solidly built. The unit's size and weight are a far cry from the typical small chassis and lightweight feel of most integrated amplifiers. Operation is simple, with three front-panel rotary knobs for volume, balance, and input selection. No bass or treble controls are provided, nor is a headphone jack. Three pushbuttons turn the unit on or off, mute the output signal, and put any device connected to the tape loop in the signal path. An LED illuminates when the unit is powered.

Four line-level inputs are provided on RCA jacks, along with a tape loop and preamp-in and power-amp–out jacks. The latter two connections allow the Integrated 1 to function as either a preamplifier or a power amplifier. If you owned an Integrated 1 and wanted more power, the unit could serve as a preamplifier to drive a separate power amplifier.

Also provided are 4 and 8 ohm transformer taps on gold-plated five-way binding posts, in order to get the best impedance match with your loudspeaker load. The Integrated 1's loudspeaker terminals look dangerously similar in layout to the "A" and "B" loudspeaker terminals of mass-market receivers. Beginning audiophiles are cautioned not to connect the 4 and 8 ohm taps to loudspeakers simultaneously. An IEC AC-line cord jack finishes off the rear panel.

An all-tube phono board is available and uses two tubes. It replaces one of the line inputs, and, whether you order the Integrated 1 with the phono board or add it on later, adds $200 to the price. It provides a specified 41dB of gain (in addition to the line stage's gain of 12dB)—enough for moving-magnet and high-output moving-coil cartridges, but on the low side for MCs in the 300µV low-output range. When driven by the 300µV-output AudioQuest AQ7000nsx and connected to the moderate-sensitivity Aerial 5 speakers, the Integrated 1 would play records at a moderate volume, but I wanted just a little more gain.

Most Integrated 1 users will have higher-output cartridges than the AQ7000—something Sonic Frontiers counted on when setting the gain midway between MC and MM levels. I liked the solution to the phono-gain question Sonic Frontiers used in their excellent SFP-1 phono preamp: Switch in a single class-A FET gain stage before the tubed stage on the moving-coil input. This technique probably wasn't possible to do in an integrated amplifier costing less than $1500.

A look inside
The Integrated 1's line-stage uses two 12AU7 tubes in a common-cathode configuration. Half of each dual-triode amplifies the signal with 12dB of gain; the other half of the dual triode forms an active load for the common cathode stage. This stage's output is capacitor-coupled to the preamp-out jacks on the Integrated 1's rear panel.

The phono preamplifier is a shielded card containing two tubes mounted in the chassis' rear left corner. The circuit is a two-stage device with passive RIAA equalization between the stages. The first tube is a 12AX7 mounted in a shielded socket, the second a 6922 (6DJ8). Both are military-grade Sovteks.

The power-amplifier section's input tube is a Philips 12AT7 dual-triode shared between the left and right channels. A 12AU7 then splits the phase into positive and negative halves for presentation to the ultralinear output stage. The Integrated 1's output stage is based on two pairs of Sovtek EL84 power pentodes per channel. The EL84 is an inexpensive tube (replacement tubes are about $5 each) used mainly in European tube amplifiers. When changing output tubes, Sonic Frontiers recommends replacing them with matched quartets. With 14 tubes (two in the optional phono stage), the Integrated 1 runs very hot. Although rated at 25Wpc, 30Hz–20kHz, the Integrated 1 will reportedly output as much as 45Wpc.

COMPANY INFO
Anthem Electronics
205 Annagem Boulevard
Mississauga, Ontario
L5T 2V1, Canada
(905) 696-2868
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COMMENTS
Chick Korean's picture

Pretty basic looking compared to Anthem's usual rather high spec cosmetics.

Jack L's picture

...... three-dimensional presentation infused with air and bloom. " qtd Robert Harley.

Is this WHAT we would enjoy in a live concert: spacious, 3-D presentation....??? For lousy $1,500, should we still demand for more ??

Anything else, e.g.bass/mid/treble hi or low is personal subjective choice & is therefore of less priority.

OnLY ALL-tubed amps can deliver such closer-to-live music enjoyment at home for genuine music lovers, like your truly.

Of course, there are still room to improve the sonic performane of this $1,500 intergrated all-tube amp if I were to upgrade its exisiting design for MY own musical enjoyment. I'd done so with my vintage Dynaco ST-70 power amp with flying colours.

But this is a commercial product. The manufacturer got to make sure it is sellable in the marketplace.

Jack L

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