[Stephen Gladwin]

I've noticed an interesting phenomenon in my Denon receiver. Often when I play a source (be it a video game, a VHS tape, or a DVD), the bass will be more noticeable in a 2-channel or "direct" decoding mode than in a Dolby Surround or Pro-logic IIx mode. Why is this? To hear the same level of bass in Dolby Digital or Pro-logic as in stereo mode, I have to turn the bass on my sub up. Is the more subdued bass in these more elaborate surround modes just part of the circuitry and the differently decoded signals? Is there any function on my Denon AVR-1706 receiver that can stabalize the bass for all surround modes? Thanks!

[John S]

Your settings can definetly effect this.


This is called bass management and I am not sure exactly what that AVR offers in the way of bass management.

LFE only for the sub would produce this effect for example.

Hard to say... My 2 channel music and even LD 2 channel content will have hot bass compared to most Dolby Digital. My AVR remembers channel level settings per mode, per source so it helps with this a lot I suppose.

I am bad though, I will adjust my center channel level and sub level per content anyways to suite my tastes. I watch a ton of older movies, often not having 5.1 on it at all and they sure seem all over the place.

I watched the DVD of the 1978 King Kong night before last, and it had only 2 channel, no encoded surround what so ever on it. The transfer sucked to by the way. At least it was anamorphic widescreen.

The movie was pretty darn good though, I was surprised. I don't remember that movie being that good back in the day.

If you have a given auto mode running on your dennon and you adjust the channel levels, don't they stay when that mode gets selected again on that source?

[Dick Knisely]

What's happening is almost certainly some facet of how the bass management is being handled and/or how the AVR is setup. I've got a Denon AVR also and "Direct" will bypass all the AVR processing and on mine at least "direct" feeds only the 2.1 channels (no center, no surrounds).

The AVR processing is somehow decreasing the perceived amount of bass from the system--but that doesn't mean there's anything wrong. It's more likely that however you have things connected and set up results in an a real or perceived emphasis in the bass.

How is the sub connected into the system? Have you calibrated the sound level outputs using the test tones or a meter? Also keep in mind that sound level outputs in direct mode won't necessarily match what you'd see in any other mode--is it possible you're just hearing that mode as louder?