- Written by John E. Johnson, Jr.
- Published on 01 October 2010
- Earthquake Sound Cinenova Grande Multi-Channel Power Amplifier with Class A Bias
- Page 2: Design of the Earthquake Cinenova Grande Power Amplifier
- Page 3: The Earthquake Cinenova Grande Power Amplifier In Use
- Page 4: The Earthquake Cinenova Grande Power Amplifier On the Bench
- Page 5: Conclusions About the Earthquake Cinenova Grande Power Amplifier
- All Pages
Besides testing the updated amplifier circuit, I asked Joseph Sahyoun, President of Earthquake Sound, to bias two of the channels at 10 watts in Class A, as opposed to all the channels in simple Class AB. My request for this is based on the fact that most of us use our home theater setup for two-channel audio as well. One simply sets the SSP or receiver to Stereo, and just the front two left and right speakers get an output signal. Class A means that current is passing through the output stage at all times, and when an input signal (music) comes through, the current is sent to the speaker. At idle (no music), the current is dissipated as heat. Of course, this is inefficient, but audiophiles don't care.
The sonic benefits of Class A are worth it. Most of the time when we are listening to a CD, the output is 10 watts or less, so that is why we chose that value in the experiment. It worked so well, as you will see below, Earthquake Sound will supply you with a five or seven-channel Cinénova Grande, custom configured with two channels biased as high as 20 watts into Class A. This is very unique, as no other manufacturer has this option.
I tested the Cinénova Grande with an OPPO BDP-83SE/NuForce Universal Blu-ray player, Anthem D2v SSP, Carver Mark IV ribbon speakers, and Paradigm Reference Signature C5 center channel speaker. Cables were Emotiva and Legenburg. For testing with Blu-ray movies, I used the HDMI connection between the player and the SSP. For two-channel listening, I used the stereo analog outputs from the player to the CD pair of analog inputs on the SSP.
There are plenty of movies to test a big multi-channel power amplifier with. Amadeus, for example, has tremendous surround sound when Mozart conducts his operas at the symphony hall. It's very powerful stuff, and the Cinénova handled it all with ease. The music is thunderous, and every hair on my body stood on end when I cranked the volume up in this movie.
The attack scene in Pearl Harbor is one of my favorite demo samples when friends are over. The machine guns of the Zero's, the Arizona when its powder magazine explodes, everything about it just begs for a muscle amp, and the Cinénova earns its classification here.
The engine room sounds are what demand power in this movie, besides being a great story with one of the best actors in the world, even if he did speak Russian with a Scottish accent. I sensed no weakness in the sound produced by the amplifier. Maybe the wall studs became a bit rattled, but not the Cinénova.
If you like the sounds of screeching winged creatures and all the violence that goes with an R-rated vampire movie, you would enjoy Van Helsing through the Cinénova.
Now to the stereo music listening. I set the Anthem D2v to the CD analog stereo input and to Stereo mode so that just the front left and right channels were being used, and this meant that only the two Cinénova channels that were biased 10 watts into Class A were being driven. No DSP was applied to the audio from the SSP in this mode. This also meant that my multi-channel SACDs were being listened to in the stereo version on the disc.
Most of the time, 10 watts is enough for casual listening, with just an occasional peak in the 50 watt range. Class A sound is a world of its own. The differences between Class A and Class AB are subtle, but noticeable. There is a smoothness to the sound that Class AB just quite can't reach. Close but no cigar. Violins have an additional correctness about them. Brass sounds more like brass and less like something that has its edges not quite in focus.
Voices sound absolutely mellifluous with Class A operation, as with this SACD of Rachmaninov's Vespers. My recommendation is that, if you purchase a Cinénova and like the idea of having two channels of Class A operation, request that they be biased 20 watts into Class A instead of just 10. When I was listening, and I don't listen to music very loud most of the time, I think the output was edging a bit higher than 10 watts for some passages. Enough that I would re-bias it to 20 watts Class A. Now keep in mind that the amplifier will get rather warm when you bias two channels at 20 watts of Class A. It will be dissipating about 150 watts of heat during quiet passages. So, I suggest getting one of those tiny fans that have a clip on one end and have the air blow over the top of the amplifier to aspirate more air up through the chassis.