The CAD 500 MB Story

I would like to bring you the story of a new set of mono bloc amplifiers I recently designed. They are called the CAD-500MB’s. The 500MB’s are a pair of solid state, discrete, true balanced 500 watt amplifiers.  In fact these music powerhouses yield 1000 watts into 4 ohms.  What, solid state from the triode tube crazed Dennis some may ask.  In fact, if one had asked me 16 years ago when I started Cary Audio… are you going to build high power transistor amplifiers? My response would have been almost in the form of a lecture about how high power amplifiers corrupt.  If the first watt is no good than why would you want 499 more? Oh, the self-righteous tube-o-phile in me would keep you listening all night. Well if I may, I would like to explain how this new solid state, high power craze came about. Or, how I became corrupted.

About six years ago, Gregg Dunn, our Cary Audio sales manager joined the company. Although he loved tubes in audio he felt we needed to seriously enter the home theater market place. Gregg convinced Billy and me that with our reputation of the best sounding two channel tube gear, we could design and become the best in multi-channel solid state amplifiers. Within about six months I completed the CAD-500-T, a five channel Cary Cinema amplifier.  It weighed in at 168 pounds, measured over two feet deep and contained five individual monster power transformers.  This new CAD-500-T was constructed of all machined aluminum. The June, 1999 issue of Home Theater Magazine featured our new monster amp on the front cover along with a glowing review. We were in the home theater arena. Well not exactly, the amplifier was sooooo heavy, sooooo large and expensive ($8000) no one wanted to lift it.  We sold a couple dozen and I was back to the drawing board. Two years later I completed the five channel Cinema 5. The Cinema 5 soon became the lead product of our new Cary Cinema line of products.  The Cinema 5 continues to receive product of the year awards around the world.  Next came the Cinema 7 and now the Cinema 7B. We won the Home Theater Magazine, 2005 Rave Award for the best cinema amplifier (Cinema 7) under $3000.  The enthusiast press, the market place and the customers were singing the sonic merits of the Cary solid state amplifiers. It was time for some two channel stereo action with this design. 

Once again, Gregg Dunn came to me with an idea. I can still hear him …. “High power, full bandwidth and low distortion in a mono amp package”.  He had this wild look in his eye as he insisted that we needed a 500 watt mono amplifier. Oh, it also had to play at 1000 watts into 4 ohms. Since Gregg has had some serious home run ideas in the past, I thought ok, let me do some basic design work.  Soon the design work turned into a passion: A personal desire on my part to produce absolute excellence in the sonic merits of this high power solid state amplifier. 

First I started with the same power supply and power transformer that ran the 5 channels of our Cinema 5. Then I proceeded to implement the basic emitter follower design that was winning all the awards. I chose direct coupled FET inputs driving bipolar Sanken high current wide bandwidth output devices.  The amplifier also needed to be true fully balanced to match some new preamplifier designs that I was completing.  The basic prototypes were sounding much too good for our listening room at the factory. I was now listening in my home listening room.  The 500MB’s had me on my hands and knees with clip leads, various parts and a soldering iron. My wife knew this was a serious project. The listening room looked like a parts depot.  Picture this scene … a pair of the new raw prototype CAD-500MB’s along with a pair of CAD-211 Anniversary Edition amplifiers sitting in line with a pair of CAD-805 Anniversary Edition amplifiers. I was into serious listening comparisons. I almost wore out a few of my records in the process.

To speed up the tale of high power corruption, within a few weeks I had become very fond of the sonic presentation from the CAD-500MB’s. The final design challenge was to increase the sound stage depth and have the midrange bloom a bit more. Well, I must say, I achieved success! The CAD-500 MB amplifiers have a deep sound stage, a glorious midrange along with enough serious power to shake the house. 

The boys and girls in the Cary Audio “toy” factory have been manufacturing the CAD-500MB’s since February.  I have heard from many satisfied customers from all corners of the world about how happy and pleased they are with their new reference quality solid state power amplifiers.  They simply love their new CAD-500 MB’s. My own pair of CAD-500 MB’s have not been turned off in my home listening room since January. They are great fun and such a pleasure to listen to with any type of music. 

Oh, get this …… Gregg has some of our custom home theater installers using … you guessed it … five (5) CAD-500MB’s in home cinema surround sound systems.  Talk about total corruption. We Love It!

Yours Truly,

Dennis J. Had
President

Written: July 27, 2005