Audio Alchemy DDP-1 Preamp/DAC/Headphone Amp, DPA-1 Stereo Power Amp, and DPA-1M Monoblock Power Amp

Value City

Equipment report
Solid-state power amplifiers,
Solid-state preamplifiers,
Digital-to-analog converters
Audio Alchemy DDP-1,
Audio Alchemy DPA-1,
Audio Alchemy DPA-1M
Audio Alchemy DDP-1 Preamp/DAC/Headphone Amp, DPA-1 Stereo Power Amp, and DPA-1M Monoblock Power Amp

Audio Alchemy blazed a trail in the 1990s with a range of ultra-low-priced products housed in utilitarian cases with no cosmetic frills. The products were almost toy-like in appearance and name—the $199 DAC-in-the-Box, for example—but contained solid engineering inside. If you could overlook the Spartan casework, Audio Alchemy products delivered exceptional performance for the money. I reviewed quite a number of these components in the mid-1990s and found them to be excellent. Audio Alchemy folded in the late 1990s, probably because it didn’t build enough profit into the products’ retail prices.

But that was then and this is now. The company is back, headed by industry veteran Peter Madnick, the design talent behind the original Audio Alchemy (and many products from other companies). Audio Alchemy has retained the same value orientation as before, but this first wave of products from the new company is a far cry from the black stamped-metal chassis and faceplates of the original. Instead, the new company’s first offerings boast upscale casework, an extensive and modern feature set, and more ambitious engineering.

The products reviewed here are the $1995 DDP-1 linestage preamplifier/DAC/headphone amplifier, along with the $1995 DPA-1 stereo power amplifier and $1995-each DPA-1M monoblock amplifiers. All are housed in compact chassis of the same size and shape, their rounded edges and satin-silver finish exuding a decidedly upscale vibe.

The DDP-1’s front panel is dominated by two large knobs, one for volume and another for input selection as well as navigating the menus. The oval display shows the input selected, the volume setting, whether the unit is locked to a digital source, the digital filter selected, and whether “resolution enhancement” is engaged (more on these features later). Four small buttons provide additional controls, including mute, selecting between headphone output and preamplifier output, and back/enter buttons that are used in conjunction with the menu/input selector knob. An 1/8" headphone jack, a feature that for many years all but disappeared from preamps but is now mandatory, adorns the front panel. The power button just below the display rounds out the controls. A well-laid-out remote handles nearly all the DDP-1’s functions.

The outboard power supply, a little larger than a “wall wart,” can be upgraded to a more sophisticated supply, the $595 PS-5 Power Station. The PS-5 is housed in a chassis that matches aesthetically with the DDP-1, “nesting” into that unit’s curved side panel. It offers independent supplies for the DDP-1’s analog and digital circuits, more elaborate voltage regulation, and more filter capacitance. Audio Alchemy claims that the PS-5 offers lower noise and wider dynamics than the stock supply.

The DDP-1’s sensible array of controls and buttons, its feel, and the display itself are all superb—this is one well-thought-out user interface. The display’s source-selection is unique; as you scroll through the list of inputs, the one selected becomes larger in type size. The remote is also outstanding; your index finger naturally falls on the volume up/down buttons. Even the volume-control ballistics are perfectly dialed-in; I could quickly make large volume changes, yet had fine control once I was in the ballpark. Moreover, the chassis’ industrial design and metalwork are far above what’s expected at this price. The compact package, with the rounded edges and satin-silver finish, is extremely attractive, and a welcome departure from the less inspired chassis work of competing products. My only complaint is that the front-panel markings are white against a silver panel, with almost no contrast. Between the low contrast and the small type, the text is difficult to read. There are, however, so few controls that it doesn’t take long before you’re operating the DDP-1 without need for the legends. Audio Alchemy reports that they are increasing the contrast of the lettering, which, incidentally, is laser-etched in the front panel. No channel-balance control is provided.

The DDP-1 offers two unbalanced inputs on RCA jacks, one balanced input on XLR jacks, and an extensive array of digital inputs. These include AES/EBU, two TosLink optical, two coaxial, USB, and even I2S. The USB input accepts PCM up to 216kHz/32-bit along with DSD64. The other digital inputs accept PCM only (also up to 216kHz/32-bit). Mac users can connect to the USB input and start playing music. Windows users must download a driver. You can select from four digital filters, including an apodizing filter. (To recap, an apodizing filter shifts the filter ringing in time so that the ringing occurs after the transient, rather than before and after the transient. This is an important distinction, because in nature we never hear part of a transient signal’s energy before the transient itself. This filter “pre-ringing” is particularly deleterious to music, and contributes to the glassy hardness of textures and flat soundstaging of most digital. In my experience, there’s a slight penalty in bass tautness and definition with apodizing filters, but it’s a worthwhile tradeoff.)

Through the front-panel display and controls, you can select any one of the filters as the default for a particular input. Similarly, resolution enhancement can be turned on and off for the individual inputs. The front-panel “Enh” legend turns green when resolution enhancement is on, red when off (see sidebar for more detail on resolution enhancement).

An important consideration when buying a DAC today is whether the its software can be updated to decode Master Quality Authenticated (MQA). I’ve written extensively about this new technology (Issues 253 and 261) that greatly improves digital sound quality. Because the DDP-1 is a purely software-driven product that runs on two XMOS general-purpose DSP chips and a field-programmable gate array, it may be possible that the DDP-1 can up updated to offer MQA decoding. Although Audio Alchemy hasn’t committed to this possibility, it’s worth noting that the demonstration board MQA has provided to manufacturers runs on the same XMOS chip used in the Audio Alchemy DAC, and that the Alchemy’s software can be updated via the read-panel micro-USB port.

Overall, the DDP-1 is a highly capable and versatile centerpiece of a system that’s a pleasure to use on a daily basis.