Perhaps a good argument for placing the port in the rear if you must go ported.
For what it's worth, the last time I put one of my ears in the port while the loudspeaker was playing, I only noticed bass. It must have been more than 20 years ago, I later switched to electrostats and then to loudspeakers of which the port is too small for my ears.
KISS
Only one more try for the simple.
Take a look at the reflex speaker reviews. There is very measurable cavity resonance and velocity noise, you know the stuff that will add up and contribute to Total Harmonic Distortion and Noise. If you can not hear it and you do not care then go for the cheap bass reflex dB's.
Thanks DT
Added thought:
If the bass reflex speaker has a 500hZ input what do expect to hear at the port? Perhaps 500hZ and some 1000hZ and 1500hZ box standing waves. That would be 2nd and 3rd Harmonics. You might even like that. It is still distortion.
Only one more try for the simple.
Take a look at the reflex speaker reviews. There is very measurable cavity resonance and velocity noise, you know the stuff that will add up and contribute to Total Harmonic Distortion and Noise. If you can not hear it and you do not care then go for the cheap bass reflex dB's.
Thanks DT
Added thought:
If the bass reflex speaker has a 500hZ input what do expect to hear at the port? Perhaps 500hZ and some 1000hZ and 1500hZ box standing waves. That would be 2nd and 3rd Harmonics. You might even like that. It is still distortion.
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Okay, I thought about it. What would happen if I put a 9 volt transistor radio inside a sealed cabinet and turned it on?
If The baseball game were on you could hear the announcer call the play by play. You could hear the crack of the ball hitting the bat and the crowd cheer as the runner rounded 2nd base.
You could hear the game not just the tuned resonate frequency of the reflex enclosure.
Thanks DT
Aaand, even if that tuned port was moving as much air as it would with the speaker playing as loud as it could (without distortion) at resonance - you'd still hear the radio playing inside.
I agree, on a klipsch rb75 (8" 2-ways), there was a lot of garbage information (peaks, resonances, etc) coming out of the port.
Voice "sounded" cleaner to me when the slot port was stuffed.
Definitely less bass though .........
Voice "sounded" cleaner to me when the slot port was stuffed.
Definitely less bass though .........
I put small bluetooth speaker inside bass box with big enough port my arm fits in and yeah sound comes out fine from the port. Situation might be different with much smaller port as it should act as low pass filter I think but with this one treble and all came out just fine.
Also listened sound coming through woofer cone and it appeared to be less than from the port, low passed more if nothing else, less distractive. Otherwise the box seemed dead silent. Conclusion, sound leaks out through the port and cone much more easily than anywhere else, according to my ear. Very scientific 😀 had RTA on smart phone on and sound through cone seemed to be attenuated roughly 10-20db. Woofer was connected to an amplifier (power on). Was quick and fun.
Also listened sound coming through woofer cone and it appeared to be less than from the port, low passed more if nothing else, less distractive. Otherwise the box seemed dead silent. Conclusion, sound leaks out through the port and cone much more easily than anywhere else, according to my ear. Very scientific 😀 had RTA on smart phone on and sound through cone seemed to be attenuated roughly 10-20db. Woofer was connected to an amplifier (power on). Was quick and fun.
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Thank you David. Could you help me to understand your graphs please, although I’m fairly confident I understand the first two.
Graph 1 : Driver response & combined Driver+Port Response. So the port response would be the difference between the two responses?
Graph 2: Port air velocity
Graph 3: I can’t work this one out!
Interestingly, graph 2 has answered another question I had about ports: Do they stop working below a certain air velocity? It seems that, by looking at the graph, output is continuous, gradually reducing with air velocity down to 0 m/s?
Graph 1 : Driver response & combined Driver+Port Response. So the port response would be the difference between the two responses?
Graph 2: Port air velocity
Graph 3: I can’t work this one out!
Interestingly, graph 2 has answered another question I had about ports: Do they stop working below a certain air velocity? It seems that, by looking at the graph, output is continuous, gradually reducing with air velocity down to 0 m/s?
So the air movement is about the the enclosure/port tuning, much like the sound a beer bottle makes when you blow across the mouth and has nothing to do with the sound that comes from the port at 3 or 4 times and greater than the resonant frequency.
DT
DT