Yamaha's Silent Cinema - does it work?

[noddin0ff]

My receiver (circa 2000) is supposed to have this feature (Silent Cinema) which is claimed to simulate a 5 channel sound field when listening with headphones. I've played computer games that created this effect very realistically so I feel I know what it should sound like.

In the 5 years I've had the thing, it's never sounded anything close to 5 channel. It's just boring, flat 2 channel

Can any of you Yami owners claim different? I just want to know. Were the older models duds?

[kexodusc]

I think it's really the software that reveals this stuff. When I use my Yammie, only computer games really give the impression of anything close to 5.1, but it's not very convincing. No better than my Soundblaster card. It's more like an inside your head type feeling.
For movies neither are very good. I think it's just a case of raised expectations and failing to deliver.

[teledynepost]

Seems odd. How would this be acheived in headphones?

[noddin0ff]

Thanks Kex. Isn't inside-your-head essentially the same as 2-channel Dolby?


Seems odd. How would this be achieved in headphones?

Glad you asked. Well...Did you ever wonder how you know sounds are coming from behind you when the source is the same distance from each ear?

The shape of your ears changes the waveform of the sound that your eardrum 'hears' differentially depending on whether that sound come from the front or the back.

This can be mimicked electronically. The way they do this is to place a microphone in the ear canal, play a sound from behind the listener and record how the sound is 'heard' from within the ear. Then they can compute the differences between original and 'heard'. Then they computationally add these differences into the source sound. If you reproduce the modified source sound near the ear canal, it 'sounds' like it came from behind.

The problems are several. 1) The effect is dependent on the shape of the ear, which is not uniform from person to person. They actually have to take recordings from a population of representative ears. 2) The effect depends on an accurately delivered (focused) sound wave. It works reasonably well with computer monitor speakers because they have narrow dispersion and the computer users head is generally a fixed distance from the center of the screen. 3) the effect is dependent on the implementation as Kex suggested.

In the first-person shooter games I've played you could practically close your eyes, turn and shoot with reasonable accuracy at a target that you 'heard' behind you- the auditory image is that good. But those sounds are relatively simple compared to a 5.1 movie soundtrack.

Still, being a believer in technology, I was expecting better, and remain disappointed.

[Woochifer]

I think it all comes down to your expectations. I think the Silent Cinema feature works well at filling in the soundfield, so that you don't have that two point sources effect that headphones can often create. It makes the overall effect with 5.1 soundtracks immersive with no huge gaps in the soundfield. Where it seems weakest is with conveying a sense of spatiality. It's also not that effective at creating directional cues from the backside, but given that you're only working with two channels without any assistance from the room/walls, I'm not sure how that effect can be realistically created with only two channels.

For comparison, you should give Dolby Headphone a try. It's available on some newer receivers, but a specially mixed Dolby Headphone soundtrack was done on the Pearl Harbor DVD and it seemed to convey the spatiality and directionality better than how the Silent Cinema feature did. It still has its shortcomings, so I wouldn't get the expectations too high. If that's how the function works with receivers as well, then I would give that a try if you're looking for a 5.1 effect with headphones.

Technology can do a lot of things, but discrete channels are still discrete channels, and there's only so much that two channels can do.