McCormac Amp Upgrade

[Huang]

Not so much new gear but an enhancement to existing equipment. I love what Steve McCormack does with an amplifier so a few years ago I bought a DNA 1 and had Pat and Steve do their thing. I come from a RF engineering background and some important tenants in a solid-state RF amplifier are local charge storage, impedance management, low dielectric constant boards,  and isolation. Steve’s designs employ all those fundamentals. DNA stands for Distributed Node Amplifier (DNA). Rather than have a few very large reservoir capacitors next to each other (and to the bridge rectifiers), the DNA technique distributes many smaller reservoir capacitors among the output stage. This amp does not sound tubey or solid state it just gets out of the way and delivers music!

During the original build of my amp they did some experimentation with pulling the power supply out of the amp case and giving the power supply a housing of its own. The power is fed into the amp via a pair of umbilicals, one for each channel I am guessing (Pat and Steve hold their techniques close to the vest). I brought the amp back to them to modify, whatever they do, they took an amp I loved and made me love it more! The power supply enclosure alone weighs 44 lbs. With the addition I hear more resolved, more immediate music with a higher and wider soundstage. The bass seems tighter. The biggest difference is the perception the music performance is happening right in the room with me (with a good recording). These improvements are not limited to some genres, but everything I’ve thrown at it has sounded better. It is true the, Vandys are a window into the music, and will produce what they are presented.

The amp sits between the speakers on the floor therefore, the power supply must sit nearby. I made a platform for the power supply to sit on. I hollowed out a section in the middle of the base and filled it with sand, the base weighs around 15 lbs. or so and seems quite dead to vibration.

               

Edited August 26 by Huang
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[GdnrBob]

Steve and Pat do great work. I had them work on quite a few pieces before I moved on to Ayre. I had no idea they moved onto a separate power supply. It must improve sound quality, as there is way too much stuff packed into an amplifier that would probably be better if moved outside. Lord knows preamps need to separate this, too.

That base looks quite nice, too.

Bob