AVM Ovation PA 8.2 modular preamplifier

The digital ground seems to shift weekly. While firmware and software updates over the Internet somewhat slow the constant upheaval, when you do buy something, you just know that as soon as you plunk down your cash, something new will come along.

So, especially with preamplifiers, why not produce a design based on modules that the user can swap in and out, to custom-configure the preamp to that user's current needs while leaving room for later expansion? Why pay for six inputs' worth of stuff when at present you need only two? Upgrades? New features? No problem—swap out a module. Or, if a circuit in one module malfunctions, you can send only that module back for repairs, not the whole thing.

It makes sense, yet in certain purist quarters there's resistance—just as there is to surface-mount technology (SMT). If the capacitors aren't the size of bathroom-tissue rolls, they can't possibly sound any good (I'm not saying that isn't true!). Modules mean plug-in circuit cards, which sometimes means computer-style [gasp!] connectors, maybe even ribbon cables. Oxidation can occur at these interfaces, so the purity of the connection can't be maintained. That's the line.

The Card-Carrying Ovation PA 8.2
Audio Video Manufaktur (AVM) is a 32-year-old German company that I think manufakturs no video products. AVM is all in with modular design. Their new flagship preamplifier, the Ovation PA 8.2 (base price $8995), like AVM's previous top preamp, has plug-in cards for both its inputs and outputs. The standard output module is their Solid-State Output card, but the PA 8.2 can be had with an optional Tube Output card ($3395), which has two AVM 803T dual-triode tubes. The PA 8.2 provides slots for up to three output cards, so biamping or triamping can be accommodated. (Each of the AVM's cards, output and input alike, is a stereo card—there are not separate cards for the left and right channels.)

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The PA 8.2 also has eight input slots, seven of which can be used for any combination of cards, though slot 8 can be used only for the Line Input Tone card ($2195). Once installed, the Tone card provides Bass, Treble, Balance, and Loudness Contour controls for all analog modules. Slots 9–11 are reserved for the output cards. However, the PA 8.2 is not limited to eight inputs. The Line Input Tone and standard Line Input ($1795) cards include both single-ended (RCA) and balanced (XLR) jacks, each of which can handle a different signal, selectable with the input-selector knob on the front panel.

The optional Digital Input Card ($3395) includes USB, optical, and two coaxial inputs. There's an optional FM Tuner Input card, as well as a Phono Input card ($2395) for moving-magnet and moving-coil cartridges. You can insert multiple Phono or FM or Digital cards—or none at all, and keep the PA 8.2's unused slots covered with blank plates (included). No doubt AVM will eventually release more cards, perhaps that include the streaming capabilities outlined in Art Dudley's review in February 2018 of their Ovation MP 8.2 CD player–D/A processor. Of course, you can also configure the PA 8.2 with only standard analog Line Input cards—as many as you need.

Basic Architecture
Behind the Ovation PA 8.2's front panel is a completely new non-modular, doubly regulated, oversize linear power supply, with two proprietary 35VA toroidal transformers supplying positive and negative voltages for all audio circuits. According to AVM's Udo Besser, the new design can handle all possible combinations of input and output modules, and maintains the shortest possible signal path through input card to output card, with not a single cable in between. Cards from the PA 8.2's predecessor, the PA 8, are fully compatible with the 8.2, and vice versa. The PA 8.2 automatically recognizes any newly installed card and correctly configures it.

There's also an independent, high-voltage power supply for the Tube Output, which you get whether or not you've opted for that card. In addition, there's a supply for the base unit's control circuitry, which manages all of the sophisticated switching and adjustment functionality. Behind the headphone jack on the front panel is a class-A headphone amplifier; most of the rest of the PA 8.2's interior is occupied by the card slots.

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The exterior case is superbly machined and constructed, with no visible bolts, screws, or fasteners. On the front panel are two large knobs with ball bearings, for Source and Volume. Between them is a generously sized fluorescent screen that displays all operating parameters and other useful information. Below that is a row of five buttons, for navigating the menu, which I found easy to understand and use. At far left is a small Power button, at far right the headphone jack.

The Ovation PA 8.2 comes with a nicely machined brushed-aluminum remote-control handset. This lets you switch inputs, change stations (if you ordered the FM Tuner card), adjust the volume, and power the PA 8.2 off or on (in standby mode). There's even a rear-panel light that alerts you to correct the AC mains phase—something that was once an end-user fetish (oldsters will remember the Namiki DF-100 Direction Finder).

Operational Completeness, Systemic Consistency
Skeptics might say, "How can you place a noisy DAC next to a high-gain phono preamplifier?" Well, each of the Ovation PA 8.2's plug-in cards has its own voltage supply. Cards installed but not in use are automatically muted to prevent interference.

The PA 8.2's configurability in some ways resembles that of a state-of-the-art home-theater preamplifier-processor: you can easily adjust each input's sensitivity so that the volume level doesn't leap up or down when you switch between them. In the Personal Setup menu you can: set the display brightness; specify whether or not the Bass, Treble, Balance, and Loudness Contour controls (assuming you've installed the Tone card) operate globally or are adjustable within individual modules; set up the system to skip any empty module slots; and name the modules. There are other options, but they don't include Mono (offered only on the Tuner card) or Mute.

Phono Input Card
This fully configurable phono-preamp module includes adjustable MM gain of 43, 46, 49, and 52dB, and capacitive loading of 50, 100, 150, 200, 260, 310, 370, and 420pF. The module doesn't include options for MM resistance loading, so I assume it's fixed at 47k ohms. The MC settings offer 63, 66, 69, and 72dB of gain, with loading options of 47, 75, 110, 150, 330 ohms, and 1k ohm.

The Phono card also has a selectable, third-order, 20Hz subsonic filter. The system is extremely convenient in that these adjustments can be made on the fly as you push the front-panel buttons—you can hear how your choices affect the sound. All that's missing (for now) are a mono option and a choice of EQ curves for pre-stereo-era mono records.

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Digital Input Card
The Ovation PA 8.2's Digital Input card is a straightforward asynchronous USB DAC that can up- and downsample up to and down from 44.1kHz to 384kHz. Deemphasis is automatic. The one optical and two coaxial S/PDIF inputs can accept PCM datastreams ranging from 16 to 24 bits and with a sample rate up to 192kHz. For Mac users, or Windows users with driver download, the USB input is good for PCM signals up to 384kHz, and DSD up to DSD128 (5.6MHz). With the front-panel pushbuttons you can select one of two filters: Fast, with steep ultrasonic filtering, for flat amplitude response in the audioband but considerable phase shift; or Slow filtering, for a gradual rolloff in the top end but less phase shift. The setting is stored even if the PA 8.2 has been turned off. You can also choose the Native sampling rate or choose to upsample or downsample, depending on the input signal's sampling rate, in CNV (conversion) mode.

Other Cards
I didn't ask for the FM Tuner Input card but probably should have: The coaxial cable for my roof-mounted Yagi antenna, with rotor, is coiled behind my rack, waiting for me to find the space for a Richard Modafferi-restored McIntosh MR67. That points to another advantage of modularity: In the same space taken up by a standard analog preamp, you can have multiple phono preamps, tuners, and DACs.

For those who must—the Bluetooth Input Card, too, was not available until after this review had been submitted. It costs $1795. There will also be a Line Out card to feed a signal to a recorder.

Setup
The Ovation PA 8.2, with headphone amp and RC3 remote control, shipped in a flight case, costs $8995. The review sample included the Solid-State and Tube output cards, the Tone and Digital input cards, and, probably just to reinforce the point to me, six Phono Input cards. This brought the grand total to $34,145. To put that in perspective, it's considerably less than the cost of each of my reference phono preamps, not to mention far less than their combined cost. And to that you'd have to add the cost of a line-level analog preamp. I think I'm safe in saying that most buyers can do without six phono preamps, so consider a more realistic but still full-function mix of cards: one output, and these inputs: one Digital, two Line, and two Phono, for a total of about $20,000, give or take.

I installed and configured the review sample in short order, thanks to the most logically laid out and easy-to-use menu system I've yet encountered: You'll never get lost in it. The cards came already installed, but judging by the manual, installing them is an easy process, and you can swap most card positions at any time to suit your needs.

COMPANY INFO
Audio Video Manufaktur GmbH
US distributor: AVM Audio USA
Buffalo, NY
(510) 901-9477
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