I know somewhere, deep in my heart, that the physical appearance and style of a preamp and amplifier should not matter—only the sound. So let me begin this review by admitting that I approach the review of D’Agostino’s Progression-series electronics with an element of extraneous aesthetic prejudice. I am more than happy to live with the serious side of audio design: Bauhaus or “form follows function” styling. (My own reference system looks as if it were styled as a result of a search for the front panel with the most controls, the effort to create the world’s largest front-panel meter, and more recently the world’s most complex and unreadable digital display.)
After decades of reviewing, however, I find that Dan D’Agostino’s willingness to add a touch of whimsy to the look of every component goes a long way. The D’Agostino Progression preamplifier and stereo power amp may not have the full-scale Baroque touches of the company’s Momentum and Relentless series—particularly the MOMA-like Lifestyle amplifier—but they do have enough styling to mix dignity with actual fun. Their colored meter lighting alone invites you to actually enjoy the music rather than simply to respect it.
Fortunately, the pleasures of the Progression preamplifier and stereo amplifier go well beyond the visual. They are true audio originals in terms of superior sound quality—something they should be at a price of $22,000 for the preamp ($26,500 with the optional DAC), and $22,000 for the power amplifier. Happily, they more than justify the money. They may not be the top of the D’Agostino line, but they provide exceptional life, dynamic detail, and apparent power, and it is hard to believe that any serious audiophile would not have even more fun listening to them than looking at them.
Features and Technology
The features of the Progression preamplifier and stereo amplifier are pretty straightforward. The basic preamp is an analog line-level stereo unit with two sets of RCA inputs, four sets of XLR inputs, and two sets of XLR outputs that can be operated separately or used with a subwoofer. The preamp has a slightly unusual Bluetooth remote that’s easy to use and has a lot more range and ability than an IR control.
Aside from that, the preamp has a minimum of front-panel switches, some useful indicator lights, and two large level-meters that actually perform a function if you use them to adjust volume or balance. There is a slim, shielded separate power supply, which fits under the control unit and does not require its own shelf space, but delivers the kind of power that top preamps need.
One key feature is that the preamp has an optional DAC that fits into its back and has coaxial, TosLink, and USB inputs. D’Agostino states that it is a fully differential DAC that handles PCM signals up to 24-bit/384kHz and DSD signals up to 4x DSD (11.2MHz). It can be added later or delivered fitted into the preamp. There are also some useful set-up options for Roon, JRiver, Windows computers, and streaming services. (Mac setup is automatic; Windows machines require downloading a driver.) Be aware that the DAC is designed for dealer installation, and the set-up instructions are basic. A bit of expert help can be useful.
As for the preamp’s circuit topology, both the analog and digital modules feed a discrete, fully complementary, balanced analog signal path from input to output. Negative feedback is not used anywhere in the preamp, but open-loop distortion is less than 0.02% and the open loop bandwidth exceeds 75kHz.
The power amplifier is, well, a power amplifier. Aside from a large front-panel meter, with some fun color options, it has no special controls. The only practical feature I’d flag is that the amp has XLR inputs only, but few audiophiles today are going to use RCA cables in any case. Like all good power amps, you put it in place, hook it up, turn it on, and forget about it, although you will want to run a mini-cable between the preamp’s 12V trigger output and the power amp’s trigger input so that the amplifier turns on automatically with your preamp.
This is not just an ordinary power amp, however. When D’Agostino uses the word “power,” he is not kidding. The Progression stereo power amp is a 125-pound unit that can deliver 300 watts into 8 ohms and 600 watts into 4 ohms. Its gee-whiz technical features include 42 output transistors, a nearly 3000VA power-supply transformer, and 400,000 microfarads of power-supply storage capacitance, and it can optionally be hooked up to a 240V AC socket.
It also has some truly innovative circuitry to help provide its power and dynamic life. D’Agostino describes this “SuperRail” circuitry as follows: “Every amplifier employs a voltage rail—actually two—a positive one and its companion negative partner. Voltage rails support the delivery of power to the speaker. The music signal swings between these two rails but due to natural loss, the musical signal never reaches the output rails’ full capability. Borrowing the idea of a turbo in a car engine, the unique SuperRail circuitry employs higher-voltage rails in the sections prior to the output stage. This voltage ‘boost’ allows the musical signal to exploit the full capability of the output voltage rails and maximize the performance of the output circuitry itself. The results are improved dynamics, lower distortion, and a fierce grip of the speaker.”
I’ll leave the hyperbole about a fierce grip to the copywriter. I didn’t see the amplifier try to grab a speaker, a passerby, a small child, or a pet during my entire review period. As I’ll discuss shortly, however, I would agree with D’Agostino that the amp has exceptionally clean sound and great dynamics.
If you do want a bit more adventurous styling, check with your dealer about cabinet and meter color options for the preamp and amplifier. It isn’t quite clear at this writing what all the options are, but it does seem that you can have a bit of fun or choose more “serious” colors.
Finally, like most high-end manufacturers, D’Agostino now puts the instruction manuals for the preamp and power amp on its website, and both are good sources of additional data on features and technology.