Cabinet design for 3 inch full range
Since this is a small speaker, 3 inches in diameter overall, I searched for enclosures for similar speakers.
There is a 3 inch Fostex unit, the FF85WK at the bottom of the page. The specificiations sheet has plans for a recommended enclosure. It is a deeper than I would have liked, however I will go with the recommended size, as there has to be space for the port tube inside the speaker cabinet.
Dimensions are roughly 10x15x22 cm which yields a volume of 3.3 litres.
The port length is 10 cm and diameter is 4 cm.
As an experiment, I placed the driver on a cardboard tube 50 cm long and 8 cm in diameter. The sound was acceptable, if muffled. A reflector at the top of the port refelcted the high frequency sounds from the driver, now lying horizontal. A ported version could sound better. Volume is 2.6 litres, however. Still not enough bass.
Since this is a small speaker, 3 inches in diameter overall, I searched for enclosures for similar speakers.
There is a 3 inch Fostex unit, the FF85WK at the bottom of the page. The specificiations sheet has plans for a recommended enclosure. It is a deeper than I would have liked, however I will go with the recommended size, as there has to be space for the port tube inside the speaker cabinet.
Dimensions are roughly 10x15x22 cm which yields a volume of 3.3 litres.
The port length is 10 cm and diameter is 4 cm.
As an experiment, I placed the driver on a cardboard tube 50 cm long and 8 cm in diameter. The sound was acceptable, if muffled. A reflector at the top of the port refelcted the high frequency sounds from the driver, now lying horizontal. A ported version could sound better. Volume is 2.6 litres, however. Still not enough bass.
Last edited:
from Full Range gallery: Full range with reflector on top. I can tell you it works. Curve the reflector and you have wide dispersion. Or so I would think.
http://www.diyaudio.com/forums/full-range/65061-full-range-speaker-photo-gallery-6.html#post744122
http://www.diyaudio.com/forums/full-range/65061-full-range-speaker-photo-gallery-6.html#post744122
Initial testing of speaker enclosure with only sides and bottom completed (placed a book on the top) are very encouraging. The speaker plays quite loud, pleasing sound quality, and audible bass, although sealing the box and adding the port tube should improve things.
Was worried all that work would go to waste and it would sound terrible!
Was worried all that work would go to waste and it would sound terrible!
Speaker enclosure completed
Completed the speaker enclosure with hardboard, Sounds boxy with the 500 hz or so peak that shows in the spectrum analysis.
As a reference speaker I used the Sony SS-333 series.
The bigger speaker shows better bass output, however many peaks and valleys in the spectrum for both, the bigger speakers bass is audible, the difference is audible and matches measurements.
Completed the speaker enclosure with hardboard, Sounds boxy with the 500 hz or so peak that shows in the spectrum analysis.
As a reference speaker I used the Sony SS-333 series.
The bigger speaker shows better bass output, however many peaks and valleys in the spectrum for both, the bigger speakers bass is audible, the difference is audible and matches measurements.
Attachments
Ran into a serious problem and considering abandoning the project.
http://www.diyaudio.com/forums/multi-way/288970-matching-speaker-drivers.html#post4660634
http://www.diyaudio.com/forums/multi-way/288970-matching-speaker-drivers.html#post4660634
Decided against abandoning the project.
I found two speakers from another defunct speaker set, the one I am trying to repair, and this time I started out by testing the output from each speaker. They were within 2 DB of each other.
I decided to use corrugated cardboard enclosures to speed up prototyping. Cardboard has been used to build furniture, a bicycle and even a church.
I built one enclosure and painted it, but that was messy, and not good for the environment, so the next one I will cover with vinyl covering or with water based paint and a thin white glue varnish.
I will use several layers of cardboard to build the enclosure, since the single thickness is not strong enough, and there are several types of cardboard to contend with.
Nothing like hands on experimenting.
I found two speakers from another defunct speaker set, the one I am trying to repair, and this time I started out by testing the output from each speaker. They were within 2 DB of each other.
I decided to use corrugated cardboard enclosures to speed up prototyping. Cardboard has been used to build furniture, a bicycle and even a church.
I built one enclosure and painted it, but that was messy, and not good for the environment, so the next one I will cover with vinyl covering or with water based paint and a thin white glue varnish.
I will use several layers of cardboard to build the enclosure, since the single thickness is not strong enough, and there are several types of cardboard to contend with.
Nothing like hands on experimenting.
Completed enclosure
They sound fine, a big improvement over the plastic enclosures. Clarity is good, bass is acceptable.
One strange thing is that the sound seems to drop out from time to time, maybe the polarity is not correct on the speakers and the sound from one speaker is cancelling out the other. Otherwise really a very good final result. All this is cardboard, and I need to improve on the fit if not the finish on this thing.
They sound fine, a big improvement over the plastic enclosures. Clarity is good, bass is acceptable.
One strange thing is that the sound seems to drop out from time to time, maybe the polarity is not correct on the speakers and the sound from one speaker is cancelling out the other. Otherwise really a very good final result. All this is cardboard, and I need to improve on the fit if not the finish on this thing.
Attachments
Need More Bass
Need more bass - sound is clear enough, but bass is less than I think I could have. One indication is that the speaker cone on the little 3 inch speaker vibrates at low frequencies, so I need a port or a slot to make these low frequencues louder.
What are my options?
- larger sealed enclosure about 7 litres as recommended
- ported enclosure
- slotted enclosure
Will the material make a difference - wood, plywood, MDF, hardboard?
There are the Fostex plans but I want the speakers to be on wall so they should be less than 10 cm deep. I could make them longer to keep the same volume.
http://www.madisound.com/pdf/fostexcabs/83e_revencl.pdf
Need more bass - sound is clear enough, but bass is less than I think I could have. One indication is that the speaker cone on the little 3 inch speaker vibrates at low frequencies, so I need a port or a slot to make these low frequencues louder.
What are my options?
- larger sealed enclosure about 7 litres as recommended
- ported enclosure
- slotted enclosure
Will the material make a difference - wood, plywood, MDF, hardboard?
There are the Fostex plans but I want the speakers to be on wall so they should be less than 10 cm deep. I could make them longer to keep the same volume.
http://www.madisound.com/pdf/fostexcabs/83e_revencl.pdf
Update: using the enclosure in #24 I have used two other PC speaker drivers that are about the same size.
How do they sound? Clarity is good, bass is adequate, but I prefer to listen to these speakers any day over the other stuff I have. Now to complete right side speaker and mount them on the walls. Material is harboard single sheet.
This looks a good project:
http://www.diyaudio.com/forums/full-range/292563-ff85wk-ufonken-project.html
How do they sound? Clarity is good, bass is adequate, but I prefer to listen to these speakers any day over the other stuff I have. Now to complete right side speaker and mount them on the walls. Material is harboard single sheet.
This looks a good project:
http://www.diyaudio.com/forums/full-range/292563-ff85wk-ufonken-project.html
Last edited:
i really like that old pc speaker look, they do not look that anymore and i think it is a bit sad, everything should look so cool today
The problem with that original plastic enclosure is that the grille caused some distortion due to interference, at least that is my take. Replacing the grille and painting them black would have worked I suppose.
The PAM 8403 is overheating and not working so I guess it is out of the running. As in this thread.
The PAM 8403 is overheating and not working so I guess it is out of the running. As in this thread.