Well, the sun is out, a rare commodity in Scotland. So I a have a choice:
Do I spend some time in the garden this weekend, or attempt to reduce the distortion in an Aurasound NSW2 wide range driver, by mounting 2 drivers back-to-back...?
Do I spend some time in the garden this weekend, or attempt to reduce the distortion in an Aurasound NSW2 wide range driver, by mounting 2 drivers back-to-back...?
Ah, practical and philosophical advice, by equal measures.
Here was my solution:
Best of both worlds; sunshine and audio!
Then the clouds came and I had to go inside (and take some measurements).
Here was my solution:
Best of both worlds; sunshine and audio!
Then the clouds came and I had to go inside (and take some measurements).
1. distortion is mainly dependent on excursion, which remains the same.
2. when your diaphragms are 6cm apart, there will be a comb filter effect from 2kHz upwards, since the phase changes by these 6cm runtime.
3. The moving mass increases not only double but all the weight of the air in the channel is additional, so the efficiency is lower than half.
Double the cost, power, weight just for a smaller cab volume?
2. when your diaphragms are 6cm apart, there will be a comb filter effect from 2kHz upwards, since the phase changes by these 6cm runtime.
3. The moving mass increases not only double but all the weight of the air in the channel is additional, so the efficiency is lower than half.
Double the cost, power, weight just for a smaller cab volume?
Hello bansuri, thanks for your comments.
It was a bit of an experiment, really, to learn something, try to reduce thd and have some fun.
Results are in!
- no improvement in thd (theoretically, the isobaric config should reduce even order harmonic distortion as it creates symmetry if the drivers are well matched)
- broad dip of around 3.5db around 1.7 kHz - this corresponds to a wavelength of 20cm, which is the length of the tube that loads the drivers (not the distance between driver diaphragms, which is 6cm
- no evidence of comb filtering - over the pistonic range the drivers should run in-sync, I think, push-pull
I will post the graphs if of interest.
It was a bit of an experiment, really, to learn something, try to reduce thd and have some fun.
Results are in!
- no improvement in thd (theoretically, the isobaric config should reduce even order harmonic distortion as it creates symmetry if the drivers are well matched)
- broad dip of around 3.5db around 1.7 kHz - this corresponds to a wavelength of 20cm, which is the length of the tube that loads the drivers (not the distance between driver diaphragms, which is 6cm
- no evidence of comb filtering - over the pistonic range the drivers should run in-sync, I think, push-pull
I will post the graphs if of interest.
Using isobarik instantly adds a poor low pass filter and above a certain point, related to the depth of the isobarik chamber. One starts to get a ripple train as the wavelengths become small enuff to start to causing the reflected wave to be in and out of pahse with the output of the front driver.
So i would suggest it would be a waste of time.
What do you have the single in?
dave
So i would suggest it would be a waste of time.
What do you have the single in?
dave