Just thinking about the rationale of why one wd squeeze a driver with a big magnet into the tightest space possible. The backwave of a driver does not go straight back w a great big magnet and spider in the way. Often with modern designs the backwave also has to contend with 3 side panels at close proximity. Surely this affects mid performance
I know narrow baffle designs are supposed to image better or is that another myth?
I know narrow baffle designs are supposed to image better or is that another myth?
I think the main rationale is to make the enclosures aesthetically/domestically acceptable by making them narrower and hence reducing the bulk of the enclosure as viewed from the front.
However, as an old school guy, the extreme depths of these enclosures really puts me off having to live with one!
And those 2 or 3 teeny-weeny bass divers - still no substitute for a single 12" driver!
Not the response you were looking for I suspect, however, I do think it is true that these eyesores image better.
However, as an old school guy, the extreme depths of these enclosures really puts me off having to live with one!
And those 2 or 3 teeny-weeny bass divers - still no substitute for a single 12" driver!
Not the response you were looking for I suspect, however, I do think it is true that these eyesores image better.
Here's a midrange in the smallest box I could make. I wanted it flat from 200Hz to 500Hz. You can see the hump caused by the small box right before 200Hz. I had a special use case where I wanted to keep a noise cancelling speaker physically close to the driver and I wanted the frequency response flat in the region of cancellation.
I included the same driver in open baffle and the manufacturer's measurement to show what it should look like. I rolled off my speakers during measurement because I had no intention of running them into higher frequencies.
Obviously, the small box has an impact that would be negative if you wanted a slower or more controlled roll off at the top and bottom.
I included the same driver in open baffle and the manufacturer's measurement to show what it should look like. I rolled off my speakers during measurement because I had no intention of running them into higher frequencies.
Obviously, the small box has an impact that would be negative if you wanted a slower or more controlled roll off at the top and bottom.
Attachments
There is the thought that the precedence effect means that diffraction will be relatively inaudible when it is close in time to the direct sound.
This doesn't consider the variations in off-axis response. Some would prefer to reduce diffraction in other, more thorough ways.
As diffraction is treated, the size of the cabinet becomes less important in this respect.
This doesn't consider the variations in off-axis response. Some would prefer to reduce diffraction in other, more thorough ways.
As diffraction is treated, the size of the cabinet becomes less important in this respect.
Well we're not talking about the smallest box here, we're talking about the narrowest. All you've shown is the effect of a under-damped closed box system.
Loudspeaker Enclosures are Waveguides
Loudspeaker Enclosures are Waveguides
"By making the baffle narrower, the beamwidth of the waveguide is narrower across it's entire bandwidth, and directivity control is extended downwards by about one octave."
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To obtain the lowest cabinet diffraction effects, B&W uses the smallest possible sphere and tapered tube driver cabinets for the midrange and tweeter. In-room speaker placement and listening-room treatments now dominate the complex-mix of direct plus indirect sound heard by the listener. A wider tweeter baffle with large radius edge round-overs will project the high frequencies foward to the listener and reduce room effects. Wider cabinets project the sound energy foward until the baffle step frequency. This can produce superior sound at the listener in AVERAGE rooms.
Loudspeaker Enclosures are Waveguides
"By making the baffle narrower, the beamwidth of the waveguide is narrower across it's entire bandwidth, and directivity control is extended downwards by about one octave."
=======
To obtain the lowest cabinet diffraction effects, B&W uses the smallest possible sphere and tapered tube driver cabinets for the midrange and tweeter. In-room speaker placement and listening-room treatments now dominate the complex-mix of direct plus indirect sound heard by the listener. A wider tweeter baffle with large radius edge round-overs will project the high frequencies foward to the listener and reduce room effects. Wider cabinets project the sound energy foward until the baffle step frequency. This can produce superior sound at the listener in AVERAGE rooms.
Out of context this suggests the opposite meaning. Patrick is talking about creating diffraction to use in a constructive way. It is the same effect described by Olsen (iirc) and used by many, including Danley.
This seems to be saying small and large are both better, perhaps it needs context, maybe a link?
The effect of a complete rollback within the driver nearfield can become something else not far out from there. The tradeoffs need to be explored to find the optimum and at this rate its conclusion isn't clear.
I do not trust your sims
open baffle would have a -6db bass slope until 500Hz (for 20cm) and then a peak of 3-8dB and then smaller ripples.
You do not consider the radiation from the back of your speaker, it is an infinite baffle
when you round the corners you get also an even response from a closed box
you also have to consider the baffle step
open baffle would have a -6db bass slope until 500Hz (for 20cm) and then a peak of 3-8dB and then smaller ripples.
You do not consider the radiation from the back of your speaker, it is an infinite baffle
when you round the corners you get also an even response from a closed box
you also have to consider the baffle step
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Back to the original question
From an idealized standpoint, the answer is "yes". Narrow baffles are inherently flawed. So are wide baffles. So are open baffles. So are multi entry horns. So are coaxial drivers ... etc etc. Everything is inherently flawed. As I use to remind my young engineers, all of our analysis is wrong, all of our designs have flaws... our job is to minimize the level of wrongness in the analysis and reduce the design flaws to those which we and our customers can live with.
From the practical standpoint of what has been shown to work well... the answer is "no". Modern narrow baffles are not inherently flawed. There are many examples which work quite well, and this proves that any flaws which a specific narrow baffle speaker might have are not inherent to the basic architecture.
Jim
From an idealized standpoint, the answer is "yes". Narrow baffles are inherently flawed. So are wide baffles. So are open baffles. So are multi entry horns. So are coaxial drivers ... etc etc. Everything is inherently flawed. As I use to remind my young engineers, all of our analysis is wrong, all of our designs have flaws... our job is to minimize the level of wrongness in the analysis and reduce the design flaws to those which we and our customers can live with.
From the practical standpoint of what has been shown to work well... the answer is "no". Modern narrow baffles are not inherently flawed. There are many examples which work quite well, and this proves that any flaws which a specific narrow baffle speaker might have are not inherent to the basic architecture.
Jim
I've heard only one example that worked quite well. They were a commercial offering from the Netherlands IIRC and were very good indeed. Wish I could remember what they were called.
Seems to me that the skinny speaker narrow baffle is just a WAF friendly trend that we want to justify with engineering.
Seems to me that the skinny speaker narrow baffle is just a WAF friendly trend that we want to justify with engineering.
The width of the baffle affect the transition from half sphere radiation to full sphere. So a old style box 50 cm wide compared to a modern 20cm baffle maintain the half space radiation to a 2.5 lower frequency and this in the octaves with the most energy. Right or wrong they are different in an important part of the spectrum.
The real problem with (very) narrow speakers is in the limit of the dimension of the mid-woofer that can be used. Bass from a 10" is different from what can be achieved with a 5" or 6" driver.
Ralf
Ralf
Yes, very close. The OP asked about backwave. Those are non-smoothed measurements of a driver in the smallest box I could fit in contrast to the same driver in an open baffle.
The OP's secondary concern was imaging.