ported to sealed

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missed the photo
 

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Hi Cal- I understand how cabinets are designed for specific drivers. I have been building these little music boxes using thrift store speakers. Most of the ones I have found so far are in sealed boxes so I make the new enclosures the same volume as the originals.
I have built a couple by making cardboard or foam core models but that’s pretty hit and miss so I am hoping there is a more efficient method.
 
Cal- I don’t know of anyone who could help measure them. They are JVC LE10007-011A, 4omh. I can’t find any parameters for them.
I was hoping there would be some kind of ratio of sealed vs ported but I guess that’s a bit naive on my part.
Given the box and port volume dimensions can the box orientation be changed from vertical to horizontal?
Sorry for the dumb questions- I should know this stuff better by now.
 
As a shot in the dark, if you downsize a ported box to about 70% of the original you can get away with going sealed but... YMMV. Try it by blocking off the port and adding some filling like pieces or wood or WHY to decrease the existing box volume before you make new ones.

A ported box usually has a lower q driver. If you take that driver and use it in a sealed, then you have to decrease the volume to try and raise the q so you get some bass. The trade off is the F3. IOW: it won't sound like the original, the bass will roll off sooner.
 
Thanks Cal- 70% is a good place to start. I have made a box with sliding inserts in the past with some success. They reason for downsizing the speaker box size is to make these compact little music boxes using TDA7297 amp modules. They are cheep, and fun to make for friends.
 

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sealed ? use 1/2 the ported volume more or less assuming the free air Q is ~ 0.3.
'apparent bass' will mostly be from any peaking in a smaller box than 1/2. otherwise use amplifier tone controls.
some folks like apparent bass, final sealed box Q >0.9, but many find it annoying after awhile
 
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I made a little test box- it works out to be about 70% of the original volume without the internal divide and 50% when partitioned. To my ear the larger 70% one has the best sound. Best being closest to the original. This is of course pretty subjective and only tested with one amp and no dampening in the box.
 

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i try same with old sony speakers, put them in very small box and closed ,as i needed them to play only to 120ish hz in 2.1 pc speakers powered by 3116 china made board with crossover. ended up using them as 2.0 speakers with my lm3886 2x20w small amplifier as i like when there is not too much bass for all day/night listening in bedroom on low volume.

so it all goes to what you expect will happen and how you put your mind to it,calculations probably make you not do this,so dont calculate.
and if low bass to you you always can put them with woofer .
 

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