Under the Hood: A/V receiver nails cost/performance trade-off

When it comes to balancing cost and performance, few areas are as demanding or competitive as home audio/video receivers. Consumers want everything (though they don't want to pay for it): 7.1 surround sound and high-definition video; 150 watts of full audio-range power per channel with 0.001 total harmonic distortion; and all the latest codecs and input/output options, from HDMI to banana plugs. Add reliability and aesthetics, and the requirements can quickly become untenable.

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Enter the designers of Pioneer's VSX-1016TXV receiver. The 1016 appealed to me as teardown fodder for two reasons. First, it's an interesting system with design issues related to audio that range from the design of the power supply right through to noise mitigation in the digital portion.

Second, it is a reasonably priced receiver, with an MSRP of $499 and aspirations to equal the quality and performance of midrange systems priced at $1,000 or more. This demanded that the designers find ways to extract component and manufacturing costs without compromising performance. According to the reviews and my own experience with the receiver, the team managed the trade-off admirably.

The main features of the receiver are 7.1 channels, 1080p HDMI, 110 W/channel, THX Select 2, Dolby Digital EX, DTS-ES and DTS 96/24, WMA PRO multichannel, and XM HD radio readiness, with Neural Surround. Inputs include eight video, three audio, five audio/video, two HDMI, six optical, three coax, five S-Video and three component video. There are two video outputs, one XM-ready output, one HDMI 1080p-compatible output, one optical digital output, four outputs for S-Video and one for component video.

The Pioneer VSX-1016TXV achieves high-level functionality, performance and aesthetics with low cost — the classic engineering trade-off realized.

According to Shirou Suzuki, Pioneer's design project leader on the VSX-1016TXV, the team sought to reduce cost without compromising performance. He said the designers had to "provide customers exactly the same sound quality for all channels in all respects, and recreate the studio engineer's original intent" in the consumer's home environment.

The first task was to reduce the number of unnecessary components to get the drastic cost reductions the team sought. One way to do that was to optimize and improve every circuit part with every block. "We focused on every capacitor and resistor, [assessing] whether the parts were really necessary," Suzuki said. The team negotiated heavily with device suppliers to push costs down further.

That led to a design with a paucity of passive components. The power supply essentially comprises two D5SBA 20 Shindengen diode bridge rectifiers, a hefty (10-pound) ATS7407 power transformer and two Nichicon capacitors for output-amplifier power stability.

The signal input and output circuits were spread across three pc boards in a stacked configuration and were driven mainly by HC4051A and LVX4053 analog multiplexers and demultiplexers from ON Semiconductor. In addition, there is one LA7109 75-ohm DVD video driver from Sanyo and a PDC131A character generator from Pioneer. The latter is likely for video overlay purposes on the video input. A Pioneer-marked ASIC controls the I/O network.