Adcom GDA 700

Continuing on in the tradition of the widely accepted and industry recognized GDA-600 D/A Converter, ADCOM has recently unveiled its new GDA-700 D/A Converter. The GDA-700 will supplement the lineup of digital offerings that has been led by the highly successful GDA-600, itself a leader in offering unprecedented performance at an affordable price.

As expected, the GDA-700 drew a tremendous amount of positive response from both dealers and industry insiders. Rob Ain, ADCOM's Vice President of Marketing expects the GDA-700 to set new performance and value standards in the under $2000.00 DAC category. "Even though I knew the GDA-700 was destined to sound good I was amazed at the openness and musicality of this unit, especially when it was decoding an HDCD encoded disc. The results were nothing short of amazing".

The GDA-700 features two RCA coaxial inputs, one Toslink® optical input and one AES/EBU on an XLR connector. All RCA jacks and XLR connectors are gold plated for maximum conductivity and resistance to corrosion.

The input receiver is the highly regarded UltraAnalog® AES21 which decodes the digital audio signal while rejecting incoming jitter. The decoded digital audio signal is then applied to the new High Definition Compatible (HDCD®) process decoder from Pacific Microsonics.

Once the digital audio signal is received, decoded and filtered, it is applied to a pair of Burr Brown 20 bit ladder-type D/A converters which convert the digital signals to analog. The output stage features class-A biased, direct-coupled, proprietary op amps which achieve extremely low levels of noise and distortion as found in ADCOM's top-of the line GFP-565 Preamplifier. The GDA-700 also offers both balanced XLR and unbalanced RCA jacks for utmost flexibility when connecting the unit to your favorite preamplifier. Again, as with the input jacks, all XLR and RCA output jacks are gold plated to ensure maximum signal transfer.

The power supply circuit for the GDA-700 is contained on a separate circuit board assembly which utilizes two independent transformers including a low noise toroidal for the analog circuitry. More than 13,000 uF of filter capacitance and multiple stages of regulation generate clean DC power supplies for the various circuit stages. RFI and EMI filtering is handled by an integral AC filter/IEC inlet with a detachable three wire AC cord.

The anodized aluminum front panel includes a power switch, an input selector, a control for digital domain phase inversion and a row of LED indicators that display the digital frequency of the incoming signal. Also included is an HDCD indicator that lights whenever the HDCD decoding process is active.

The GDA-700 will carry a suggested retail price of $1000.00 and can be found at ADCOM dealers nationwide.

ADCOM, long prominent in the design, manufacture, and marketing of high performance, high value audio components is based in East Brunswick, NJ.

Note: For those unfamiliar with Pacific Microsonics' HDCD, this new process in the form of a decoding chip provides qualitatively improved digital filtering when conventional CD's are played and provides HDCD decoding for new HDCD encoded CDs. The latter is accomplished by using an HDCD encoder which has a word length longer than the conventional 16 bits and a sampling frequency higher than 44.1 kilohertz. This high resolution signal contains more information than would fit onto a conventional CD. Therefore a continuous, real-time analysis of this signal is made taking advantage of technologically advanced DSP techniques to determine which elements beyond the range of a conventional CD are important. After being identified, this high-resolution information is encoded on to a standard CD and eventually decoded using the HDCD decoder to precisely reconstruct the high-resolution signal which is fed to a pair of suitable D/A converters for analog conversion.