You mentioned a yamaha sound bar, do sound bars in general have sub out which can work with this sub?
Iv never heard a sound bar most look small so i wondered if they are any better than the tv built in speakers.
Also iv never known bass to be in stereo.
but if you only got 1 sub in the room how do you get stereo bass? not like people have 2 subs left and right.
low frequency sounds being omni directional etc.
That doesnt explain stereo bass. The example of the tank is talking about a stereo signal to a single sub but you cant do stereo with just a single speaker. Combined to mono is whats normally done.
So in your tank example the tank going from left to right how would that work with a single sub? Or does someone move the sub to the other side of the room when the tank exits ?
My guess is you're only saying about bass being mono as a routine method because all you've ever experienced is PC speakers and home cinema kits with a single sub and small satellite speakers. That's the sum total of your knowledge, but there's a bigger world out there.
Have a look at the image below. You're seeing all the equipment in the system. Nothing else if off to the sides or out of shot. Now, given the size of the speakers, do you really think that they don't produce deep rumbling bass?
Here's an image of a different system. This time you're seeing just the front sound stage. The side and rear surround speakers are off shot, but that's less relevant. Do you notice the two subwoofers? That would be stereo subwoofers, wouldn't it? This rather explodes your idea that bass is mono as in "
you only have a single subwoofer".
A stereo hi-fi signal is typically two channels of sound with a frequency range of 20Hz to 20kHz. Most simple stereo systems with either larger stand-mounted speakers or floor-standers won't have a sub. The speakers will get the whole frequency range and play down to whatever frequency they roll off at.
Roll-off means the point where the speakers volume starts to drop off at progressively lower frequencies.
The model number of the large black speakers in the top picture is
B&W 800 D3. These have a frequency range quoted as 15Hz to 28kHz +/-3dB. At 15Hz the speaker is still producing useful sound, albeit at half the volume level of an octave higher which is 30Hz. This is better than a a lot of powered subs with 8-10" drivers. By contrast, that Philips sub with its 6.5" driver doesn't have a proper specification. The service manual for it quotes a lower frequency of 30Hz, but without a roll-off dB figure then the number is meaningless.
When it comes to movie sound tracks in domestic audio formats, be it Dolby Digital, DTS, Dolby TrueHD or DTS Master Audio, all five or more main surround channels are also a minimum of 20Hz-20kHz. This means that if you had the room and enough spare cash you could have say three pairs of the £23,000/pr B&W 800 D3 plus their matching centre speaker, and each could get full 20Hz-20kHz audio with no real need for a sub at all.
The only part of a movie sound track that is both bass and mono is the LFE channel. LFE stands for Low Frequency Enhancement. It has its roots in the 1950-60s when the cinema industry was experimenting with wider screen formats than Academy Standard and exploring stereo and multichannel sound.
LFE exists because there wasn't enough scope in the existing stereo soundtrack space to increase the bass level to wow audiences. Having an extra track dedicated just to deep bass, with the upper frequency pegged at 120Hz and the lower frequency of 3Hz(!!) meant that the additional volume was on tap when needed for the big explosions and other deep bass effects.
LFE first appeared in mass market consumer audio with the arrival of Laser Disc and AC3 multichannel audio in the 90s. It was niche market stuff though. DVD and Dolby Digital processing in the late 90s changed all that. DTS followed within 18 months. Suddenly home cinema systems were a thing that people were getting in to.
It was obvious though that expecting consumers to have floorstanding speakers all round the room was impractical. There was also an issue with amplifier power. There wasn't enough to to do 5 channels of full frequency audio. This is part of the reason why AV amps and AV receivers have
bass management. It filters the main channel frequencies to split away the bass and direct it to the sub which is already handling the LFE track. This is how we arrived at the sort of sub/sat systems from which your Philips SW3800 sub came from.
Main channel bass is not mono. It only becomes mono if the bass management in a processor splits and sums it to a single channel. LFE is the only true mono bass track.
