Grimm Audio

Let us introduce the four members of the Grimm Audio company:

Bruno Putzeys
Electrical Engineer. Has been active since 1995 designing class D power amplifiers for high-end and consumer audio applications, digital and analogue deltasigma and PWM modulators, AD/DA converters and discrete solid-state analogue audio circuits. Has further experience with vacuum tube electronics and loudspeaker design. Now working for Hypex, he was formerly employed at Philips where he invented, among others, the "UcD" power amplifier circuit.

Peter van Willenswaard
Electrical Engineer. Owner of company Audiomagic. Specialized in upgrades for digital audio equipment and upgrades for and repair of tube audio equipment. Design and construction of analog and digital equipment for consumer and professional clients. Former technical editor of Dutch pro audio magazine Pro-Audio&Visie (1989-1993). Long career as technical audio journalist (since 1982).

Guido Tent
Electrical Engineer. Runs the Tent Labs company. Develops,
manufactures and supplies low jitter clock upgrades for digital
products like CD/DVD players, ADCs and DACs. Consultant in the area of EMC, RF electronics and signal integrity. Career in analog electronics, RF and EMC (silicon and system design). Formerly employed at Philips Optical Storage where he was involved in the design of DVD-R pick-up units.

Eelco Grimm
Sound Engineer. Owner of the Fairytapes company for recording and acoustic consultancy. Former editor in chief of the leading Dutch professional audio magazine Pro-Audio&Visie (1992-2000). Writer of the book (with test cd's) 'Checkpoint Audio'. Teacher and researcher at the Utrecht School of the Arts, Media and Technology. Co-inventor of the 'Omnisurround' solution for realistic surround acoustic reproduction.

AD1 | Grimm
Operating directly at 1 bit, 2.8224MHz, the AD1 | Grimm is eminently suitable for creating SACD masters from analogue sources. Additonally, DSD processing DAW's will find no better front end. Combined with our DD1 digital converter, the AD1 offers the best CD rate converter performance available.

In order to get past the limitations posed by commercially available converter chips, the AD1´s converters are made with discrete parts. The input circuitry before the modulator consists of only two resistors. This strategy pays off with unparallelled low noise and distortion, while delivering data that can be directly pressed onto SACDs or processed in a DSD workstation.

 Maximising the converter´s capability are a plethora of design techniques such as:
an ultra-low jitter clock source delivering the same precision irrespective of whether it is operated in locked or free-running mode;
EMC by design. From the very first planning stage onwards, parasitics were considered as an integral part of the circuit, not something to be worked around at the end of the development cycle;
extensive use of wideband, quiet point-of-load shunt voltage regulators that effectively keep AC currents associated with the operation of analogue or digital circuits local, rendering interference between circuits zero;
choke power supply filter, providing clean power to the shunt regulators;
audiophile construction details such as selected capacitor types, 'melf' resistors and DC coupling.

The AD1 is constructed modularly and is available in 2 to 8 channel versions, cascadable for an unlimited number of channels. The outputs are SDIF3 compatible. A companion box, the DD1, converts these signals into various PCM formats through nonaliasing, ripple-free decimation filters. The DD1 is planned for release Q1 2007.

Read the AD1 specifications or download the Grimm AD1 leaflet pdf.
For even more in depth information, download the AD1 manual pdf.

Grimm Audio
Waterhoenhof 8
3582 DE Utrecht
The Netherlands
Tel:+31 (0)30 236 9829
Tel:+31 (0)40 213 0186
Fax:
E-mail:

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