So I decided to make use of my cheaper sub that only goes down to 40Hz for a stereo sub experience.This is ridiculous hahaha, Can someone just send me £450 so I can buy another PB1000
- REW generated EQs
- User EQ
- Equal loudness contours Volume control
- Crossover for mains and subs
- Delays to time align subs to main
- Extra crossover for the cheap sub to pass through below 40Hz to the good sub
- (5.) delay numbers measured to account for the delay from the extra linear phase crossover on the cheaper sub
Someone moves a speaker by 2cm here and that’s me needing to take a week holiday to re-measure and calculate everything.
The stereo subs make a lot of things better and a very good centre image but overall the quality of the cheap sub even at 80Hz is not on par with the PB1000 and it does stand out. Not sure if I’m gonna keep it yet
I only EQ’d this with RTA mode and didn’t capture THD.But for time alignment I record an 80HZ sample from each speaker and check how many samples I need to delay a speaker by so that the output from each is exactly on top of each other. Even just doing this I could see that the wave from the cheap sub is less of a perfect sine wave and also surprisingly not perfectly regular. Time aligning the first peak would align most but on some waves it still started to start early or finish early or late. So I would guess that if I can see major issues just looking at an 80HZ waveform, that the THD is quite high
yeah so that means you’re going to be generating tons of overtones in the cheap sub.
super low frequencies tend to be non-directional (well, less directional, depends on the room) but it’s pretty easy to localize 160Hz and 320Hz overtones, so high subwoofer THD is going to mess up your stereo image.
dual sub rigs can be great though but i think in this case unless you’re using it to quietly fill in very specific null frequencies the cheap sub will be making things worse.