@Freedom666
But of course, it's a complete DIY project, except for the amplifier modules, which are based on icePower.
But of course, it's a complete DIY project, except for the amplifier modules, which are based on icePower.
The grandson had a wild idea to make a Rocket Sub a couple of years ago.
It's a 4th order bandpass design, using an 8" up-firing woofer mounted on a sealed cylinder, and inside a 10" vented cylinder. Quik Tubes (concrete form cardboard tubes) were used. The space between the tubes acted as a vent.
Sippy cups wrapped with foil tape were used for the engines.
A large paper cup was used to make a pattern for the fin fairings. The cup was cut at an angle with the bandsaw. The cut piece was flattened out for a pattern.
The -3 dB pt is around 30 Hz - better than the simulation. Works fine with the bookshelf speakers he has in his room.
Definitely a FUNtastic FUNctional project!
It's a 4th order bandpass design, using an 8" up-firing woofer mounted on a sealed cylinder, and inside a 10" vented cylinder. Quik Tubes (concrete form cardboard tubes) were used. The space between the tubes acted as a vent.
Sippy cups wrapped with foil tape were used for the engines.
A large paper cup was used to make a pattern for the fin fairings. The cup was cut at an angle with the bandsaw. The cut piece was flattened out for a pattern.
The -3 dB pt is around 30 Hz - better than the simulation. Works fine with the bookshelf speakers he has in his room.
Definitely a FUNtastic FUNctional project!
Attachments
I built these ages ago (before I had measurement capability), then re-did the crossover during the pandemic. They're good fun, they came from Minnesota to California with me.
fun loudspeaker portable bluetooth
some info on how I modified it
added damping
added 1 ohm in line with the bass for a little bit of current drive by added resistance
EQ for corner placement (you can really gain headroom like this!)
EQ for against back wall
some info on how I modified it
Portable bluetooth box with piezo which deserves attention.
Original is 2.2uF in line nothing else.
Will get some resistor from plus to minus and checking polarity.
Box got damping (had none) and the paper cone some aluminium treatment
Original is 2.2uF in line nothing else.
Will get some resistor from plus to minus and checking polarity.
Box got damping (had none) and the paper cone some aluminium treatment
update to post 29 in this thread.
The piezo tweeter must be reversed there is a suckout at 3khz. Will report when turning its phase if it gets more linear.
box 25cm measured between driver and tweeter
close to tweeter 5cm
The piezo tweeter must be reversed there is a suckout at 3khz. Will report when turning its phase if it gets more linear.
box 25cm measured between driver and tweeter
close to tweeter 5cm
added damping
added 1 ohm in line with the bass for a little bit of current drive by added resistance
EQ for corner placement (you can really gain headroom like this!)
EQ for against back wall
testing a
dispersion / diffuser / waveguide element
in front of the 12 inch driver.
Sound could be more "warm" with more mids.
Maybe it will do some good.
Its attached to the protective grill not the driver
ventilated the dustcap and yellow spider, subtle but clearly more articulate sound
opening facing downwards hoping it collects like this less dust.
dispersion / diffuser / waveguide element
in front of the 12 inch driver.
Sound could be more "warm" with more mids.
Maybe it will do some good.
Its attached to the protective grill not the driver
ventilated the dustcap and yellow spider, subtle but clearly more articulate sound
opening facing downwards hoping it collects like this less dust.
now I found the solution to remedy the "cold" sound presentation:
damping the 5cm high plastic surrounding. Together with a grill not much transparent there are vagabonding resonances like in a cavity murking the sound.
Now the mids come much better through fullrange speaker alike.
Again in the frequency response not much change maybe in the burst decay which I did not measure.
since the BBC LS 3/5a we know that edge diffraction influences the sound.
Remedy applied makes a big sonic difference.
damping the 5cm high plastic surrounding. Together with a grill not much transparent there are vagabonding resonances like in a cavity murking the sound.
Now the mids come much better through fullrange speaker alike.
Again in the frequency response not much change maybe in the burst decay which I did not measure.
since the BBC LS 3/5a we know that edge diffraction influences the sound.
Remedy applied makes a big sonic difference.