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How much space before a speaker port chokes?

abdo123

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I'm trying to do a flush mount of some speakers I have (or something close to a flush mount) and I was wondering how much space infront does the port requires?

What do ports do exactly? and what should I expect if I were to choke a port on a speaker?
 

Rick Sykora

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Hi. May have to explain a bit more. Perhaps you meant chuffs rather than chokes?
 

Matias

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It's a good question. Some speakers with down firing ports have like 10 cm clearance before the floor, so I suppose this is the distance that is really required?
 
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abdo123

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Hi. May have to explain a bit more. Perhaps you meant chuffs rather than chokes?

well I just mean blocked by something so the air inside the port cannot be as easily displaced.

However, I would very much appreciate a 'simulation' of these two scenarios

1) a port blocked by an infinitely rigid surface (i live in a sky scraper, walls are thick reinforced concrete).

2) a port is blocked (not stuffed) by speaker cabinet damping material.
 

Frgirard

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I'm trying to do a flush mount of some speakers I have (or something close to a flush mount) and I was wondering how much space infront does the port requires?

What do ports do exactly? and what should I expect if I were to choke a port on a speaker?

REW can help you.
 

voodooless

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This is not based on any actual science, an educated guess: take the diameter of the port and use that as the minimum distance to the wall. It might be that this lowers the tuning a tiny bit, but the closeness to the wall make up for it.
 

AdamG

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I'm trying to do a flush mount of some speakers I have (or something close to a flush mount) and I was wondering how much space infront does the port requires?

What do ports do exactly? and what should I expect if I were to choke a port on a speaker?
This is something that may vary from speaker to speaker. A good question to pose to the OEM of the Speaker.
 

mSpot

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What do ports do exactly? and what should I expect if I were to choke a port on a speaker?
Which speaker model do you have, and how much clearance does the manufacturer recommend for speaker placement?

Ports are used to tune the response of the woofer and increase bass. The port relieves air pressure in the cabinet so the woofer cone can move more freely, and sound is emitted from the port opening itself. When a rear ported speaker is placed close to a wall, the bass coming from the port is reinforced and reflected by the wall, which may cause a bloated sound, and in that case it may help to plug the port. Plugging the port partially or completely is a common way to tune the sound of a speaker to adjust for speaker placement and room response. Some manufacturers actually provide a port plug with the speaker to optionally adjust its sound for different situations.

In summary, blocking the port will change the frequency response of the speaker. The change may go in a good or bad direction depending on your speaker placement. You'll just have to try it.
 

Senior NEET Engineer

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Put your hand in front of the port and feel the point where it drops off
 

Chrispy

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Most often I've seen mentioned is that if the distance to the boundary is at least twice the diameter of the port, its sufficient. Some block the port when integrating with a sub....
 
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