This is my first post so I am expecting someone to point out that I have already blundered.... but here goes:
I think I understand that destructive interference occurs in the mid frequencies as a result of bipolar speaker configuration. I remember reading something Planet_10 said: that constructive interference is less likely to occur than destructive: that dips are more common than peaks with this set-up, and that dips in the frequency response are less noticeable than are peaks.
Is this correct? And if so, why is it the case? I would assume that the interference would occur in equal proportions.
I also read that a lenticular baffle could help minimize this consequence of bipole design, and that a baffle which is wider than the distance between the drivers helps improve response by moving the band in which the comb-filtering occurs.
Can anyone dispel any of these misconceptions, or otherwise guide me toward the appropriate reading material? I would love to read about bipole speakers!
Thank you diyaudio community!
I think I understand that destructive interference occurs in the mid frequencies as a result of bipolar speaker configuration. I remember reading something Planet_10 said: that constructive interference is less likely to occur than destructive: that dips are more common than peaks with this set-up, and that dips in the frequency response are less noticeable than are peaks.
Is this correct? And if so, why is it the case? I would assume that the interference would occur in equal proportions.
I also read that a lenticular baffle could help minimize this consequence of bipole design, and that a baffle which is wider than the distance between the drivers helps improve response by moving the band in which the comb-filtering occurs.
Can anyone dispel any of these misconceptions, or otherwise guide me toward the appropriate reading material? I would love to read about bipole speakers!
Thank you diyaudio community!
I suggest that you checkout Duke LeJeune's work on bipole speakers. Try this in Google for directions:
'duke lejeune on bipolar speakers'
'duke lejeune on bipolar speakers'
Great read Jim, thanks. Going to have to try that out, will it work with full range drivers?
Larry
Larry
Read this thread on my offset bipolar speaker adventure at:
Offset Bipolar MLTL with CSS EL70 Drivers--Part 1
Offset Bipolar MLTL with CSS EL70 Drivers--Part 1
Thanks Jim, This is really interesting.
I took some of the ideas I have read on this forum and the frugal-phile website applied them in a naive way to a portable speaker I was asked to design. My friends run a solar charged battery battery exchange outfit in rural Tanzania, and this is the first time these families have had electricity at home. This going to be their first speaker so it is a big deal.
I "came up" with a bipolar design using 15w full range drivers assisted with passive radiators (too dusty for vents) in a 2.7 Litre enclosure.
The first run is being made now!
What myself and everyone is wondering is, why does this $15 speaker sound so good?
When I made single driver prototypes they sounded pretty bad: thin bass, the voices sounded like they were coming from a box, and sometimes it would honk. But with the bipolar configuration the bass is ... there, and everything just sounds smooth and rich. Our clients will likely be using the speaker outside often, and man it sounds great outdoors.
I want to know why! But it isn't so easy. I'm basically hooked at this point.
Anyways, thanks for suggesting these articles.
I appreciate so much the exchange of information within this community.
I took some of the ideas I have read on this forum and the frugal-phile website applied them in a naive way to a portable speaker I was asked to design. My friends run a solar charged battery battery exchange outfit in rural Tanzania, and this is the first time these families have had electricity at home. This going to be their first speaker so it is a big deal.
I "came up" with a bipolar design using 15w full range drivers assisted with passive radiators (too dusty for vents) in a 2.7 Litre enclosure.
The first run is being made now!
What myself and everyone is wondering is, why does this $15 speaker sound so good?
When I made single driver prototypes they sounded pretty bad: thin bass, the voices sounded like they were coming from a box, and sometimes it would honk. But with the bipolar configuration the bass is ... there, and everything just sounds smooth and rich. Our clients will likely be using the speaker outside often, and man it sounds great outdoors.
I want to know why! But it isn't so easy. I'm basically hooked at this point.
Anyways, thanks for suggesting these articles.
I appreciate so much the exchange of information within this community.
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