When Carver Corporation was still in business and Bob was still churning out audio equipment designs within that company that bordered on magic, I did not have the means to purchase much of it. The technology that intrigued me the most was Sonic Holography. I first heard the affect when Polk first introduced their SDA line of speakers. Then I saw an ad describing Sonic Holography and was perplexed but intrigued by how the same affect could be produced entirely electronically. Carver at the time would send you a thin vynl recording with the cancelation signals recorded into it. When I listened to it I was hooked and had to have a C-9, which I eventually saved up for and hooked up to my venerable NAD 3020 integrated amp. That had to be back around 1980. It's been in my slowly evolving system ever since. Over the years I've used it and not used it, always debating with myself whether or not it colored the sound or enhanced it, or both. I'm presently enjoying it again, saying the hell with over analysing it, I like what it does. What I'm looking for here, is other peoples experience and knowledge about this technology, whether used as a separate component or imbedded in a preamp or receiver. Following is some of my observation and experience with Sonic Holography over the years.
1. Speaker placement needs to be closer together than usual without SH.
2. I have never found listening sweet spot as critical as people have complained about. I would sit in that spot with or without SH. I've heard people say that your head moving as much as one inch causes the image to colapse. I find I have as much as a foot in either direction and can turn my head and look at the solid location of individual instruments to the outside of the speakers without losing the image.
3. Spectral tonal balance seems to tilt up slightly brightening most recordings. Now Carver literature has always said that the SH circuitry introduces no tonal coloration and I believe there is no equalization going on here. So I've always wondered if it's the extended separation that causes this, such as you hear when you switch back and forth from mono to stereo.
4. I always here more ambience with SH engaged and sometimes artificial reverb is exagerated. My theory here again is enhanced separation. Most ambient signal I believe comes from the extreme L-R L+R part of the signal, which is clarified through crosstalk cancelation? And if reverb is taking place in that part of the signal it will be exagerated?
Well I hope people will chime in here. I'd love to see Bob Carver himself add his knowledge.