search
The DSPro Basic's heart is the computing section consisting of two Motorola 56001 DSP chips and two ROMs that contain the decoding algorithm for the 56001s. The DSPs perform 8x-oversampling which, according to Mike Moffat, is optimum for this amount of computing power and DACs. He contends that DACs start to sound worse as they are driven at faster and faster speeds by high oversampling rates. An additional benefit is that some computing power is reserved for other functions that are done in software, rather than hardware. For example, the Basic performs de-emphasis in the digital domain…
The DSPro Basic's soundstage depth seemed to combine synergistically with its remarkable transparency. There was no sense of veiling, congestion, or fog. Instead, the Basic provided a transparent window on the music that was luscious and inviting. Music had an openness and clarity seldom heard from digital playback at any price. This transparency, coupled with the ability to reveal spatial nuance, allowed me to see into the music as though it were clear crystal. Instrumental outlines were resolved in three dimensions, with air and space around them. Images floated between, above, and behind…
Sidebar 1: Specifications
Description: 8x-oversampling, dual 18-bit digital signal processor. Inputs: two digital coaxial on RCA jacks. Output: 1 digital (S/PDIF) on RCA. Analog outputs: unbalanced RCA jacks. Sample rates handled: 44.1kHz, 48kHz. Frequency response: 20–20.5kHz +0, –0.1dB. S/N ratio: 104dB. THD at full output: Less than 0.001%. Output level: 3.4V RMS minimum.
Dimensions: 19" W by 2¼" H by 14" D. Weight: 17 lbs (shipping).
Price: $1995 (1990); no longer available (2009). Approximate number of dealers: 66.
Manufacturer: Theta Digital, Agoura Hills, CA 91301 (1990…
Sidebar 2: Review System
The Theta DSPro Basic was auditioned (after an epic struggle prying it away from Dick Olsher) in my reference system, which consists of VTL 225W Deluxe monoblocks driving Hales System Two Signature loudspeakers, with level control provided by an Electronic Visionary Systems Stepped Attenuator passive control unit (reviewed last month, along with the Hales signatures). The preamp, used briefly, was a Classé Audio DR-5 (footnote 1).
Speaker cable was AudioQuest Green Hyperlitz and interconnect the Expressive Technologies IC-1, Music Metre, and van den Hul D…
Sidebar 3: Measurements
Not surprisingly, the DSPro had flat frequency response (fig.1) and virtually no de-emphasis error (fig.2), due to the fact that de-emphasis is performed in the digital domain. The Basic's channel separation (fig.3) was fairly typical, but with greater separation at mid and high frequencies. Unusually, the DSPro Basic did not exhibit flat phase response. Instead, interchannel phase increased with frequency, reaching a maximum difference of 42°, as can be seen in the plot of fig.4. (This is equivalent to a time delay of 6µs between the two channel outputs, which is…
"The victor belongs to the spoils."—F. Scott Fitzgerald, The Beautiful and the Damned, 1922
The New York Times reported that more than 3000 foreigners had abandoned their cars at Dubai airport (footnote 1). Deep in debt and out of work, had they stayed they could have been thrown into debtor's prison, just as in the London of 200 and 300 years ago. (Charles Dickens's father languished in debtor's prison. So did Samuel Johnson, until a friend sprang him. The Debtor's Act of 1869 abolished this.)
Mercedes, BMWs, even Maseratis . . . abandoned in the dust.
I'll bet…
Most high-end components' front panels, or faceplates, represent 30% of the build cost, averred Antony. This squares with what another well-known manufacturer told me many years ago, off the record: that he could reduce his retail prices by 40% if he didn't offer them as hi-fi jewelry.
"With the exception of power amps that require big heatsinks and large transformers, every other component does not need to be housed in a big box," Antony continued by phone. "Manufacturers try to fill the box with stuff which looks impressive and powerful, but it's meaningless with low-level signals…
Sidebar 1: Specifications
Dimensions: 6.7" (170mm) long by 3.75" (95mm) wide by 1.7" (40mm) high, including all feet and terminals.
Price: $299.
Manufacturer: Musical Fidelity, Units 24-26, Fulton Road, Wembley HA9 0TF, England, UK. Tel: (44) (0)20-8900-2866. Fax: (44) (0)20-8900-2983. Web: www.musicalfidelity.com. US distributor: KEF America at time of review; Tempo Sales & Marketing, P.O. Box 541443, Waltham, MA 02454. Tel: (617) 314-9296. Fax: (617) 336-3486.
Sidebar 2: System
Digital Source: Marantz CD63 Special Edition and Denon DCD-1650AR CD players, Cambridge Audio DacMagic D/A processor.
Integrated amplifier: LFD Integrated Zero Mk.III.
Headphone amplifier: Musical Fidelity V-CAN.
Headphones: Audio-Technica ATH-AD700.
Loudspeakers: Harbeth Compact 7ES3.
Digital cable: Analysis Plus Digital Oval S/PDIF.—Sam Tellig
Sidebar 3: Measurements
The V-DAC offers bare-bones construction. The power supply is a separate wall wart. A plain, black-painted box of extruded aluminum carries a single printed-circuit board, with the input jacks (TosLink, coaxial, USB) at one end and a single pair of RCA output jacks at the other. Other than three surface-mount LSI chips, the circuitry is based on traditional through-hole components, and local voltage regulation appears to be performed with the usual ±5V chips. The USB input feeds the ubiquitous Burr-Brown PCM2706 receiver chip, which is limited to 16-bit data and…