10 minute OB FAST System
I had an old refrigerator box that I was flattening for recycling and noticed it was about right size for an open baffle. I cut the box into two 90 deg sections and glued a piece of foam core for reinforcing the driver mount. Cut two holes for TC9FD and mounted them, then I put a ported sub woofer (old JVC labrynth subwoofer speaker) behind the baffle and aimed port backwards against wall. So with a sub assisting a full range, I guess I have a FAST with an OB. I hooked up the A output from Yamaha amp to Vifa's and B output to JVC subs no crossover. I have never heard an OB before and I was pleasantly surprised to hear that it was pretty good - very spavious open sound with nice mids and highs. I even tried bi-amping by driving Vifa's with Lepai T-amp. That allowed me to independently control level of sub woofer and bass which was nice to overcome baffle step. Cardboard is fugly and there is no way I am keeping this long, but it was fun and quick. 10 minutes from idea to first sound. Pretty cool and fun if you have never tried open baffle before. In case you are curious, I did an A/B comparo of the FH3-inspired horns and the OB, the horn wins in imaging and vocal clarity and cleanliness of bass compared to sub. I think what surprised me is how good cardboard and 10 minutes of effort can sound! I mean for a small party, these would have been more than suitable for some fun with friends and drinks.
I had an old refrigerator box that I was flattening for recycling and noticed it was about right size for an open baffle. I cut the box into two 90 deg sections and glued a piece of foam core for reinforcing the driver mount. Cut two holes for TC9FD and mounted them, then I put a ported sub woofer (old JVC labrynth subwoofer speaker) behind the baffle and aimed port backwards against wall. So with a sub assisting a full range, I guess I have a FAST with an OB. I hooked up the A output from Yamaha amp to Vifa's and B output to JVC subs no crossover. I have never heard an OB before and I was pleasantly surprised to hear that it was pretty good - very spavious open sound with nice mids and highs. I even tried bi-amping by driving Vifa's with Lepai T-amp. That allowed me to independently control level of sub woofer and bass which was nice to overcome baffle step. Cardboard is fugly and there is no way I am keeping this long, but it was fun and quick. 10 minutes from idea to first sound. Pretty cool and fun if you have never tried open baffle before. In case you are curious, I did an A/B comparo of the FH3-inspired horns and the OB, the horn wins in imaging and vocal clarity and cleanliness of bass compared to sub. I think what surprised me is how good cardboard and 10 minutes of effort can sound! I mean for a small party, these would have been more than suitable for some fun with friends and drinks.
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I work in boats all the time, so I always have some lying around, never noticed about the price. Guess you are right.
One late night, well a six years old go to bed quite early, but anyway I did steal back some foam board.
And built a Mini BiB's..
Hang on, is fast but not as fast, as the glue dries in 5 minutes ..
First, measure twice
3 minutes later, cutting
All the pieces took about 10 minutes to cut
Starting to glue
Made one or two small mistakes along the way, that made it took a little longer than necessary
Among other things, that the speaker did not fit, so I had to build a small box behind the magnet. Wait that was not really my fault i guess.
Damping in place
Tried not to repeat the mistake they made in Italy when they built the Leaning Tower of Pisa, trying to cut the bottom straight.
Upside down, and five minutes drying time, what a waste of time ...
Playing time..
How should I describe the sound then?
WOW, I'm stuck, feel a new addiction coming
Of course they do not rattle any windows, but there are enough bass so that's really fun to listen to Vicious Delicious by Infected Mushroom.
But they need not be ashamed when they play Ohio by Over The Rhine or Joy to my soul by Oslo Gospel Choir.
Oh sorry picture of speakers used..
The NS3 is running full range, the Vifa tweeters are not connected.
Already having some ides for the next build. Only have to find a store that sells foam board cheap.
\M
And built a Mini BiB's..
Hang on, is fast but not as fast, as the glue dries in 5 minutes ..
First, measure twice
3 minutes later, cutting
All the pieces took about 10 minutes to cut
Starting to glue
Made one or two small mistakes along the way, that made it took a little longer than necessary
Among other things, that the speaker did not fit, so I had to build a small box behind the magnet. Wait that was not really my fault i guess.
Damping in place
Tried not to repeat the mistake they made in Italy when they built the Leaning Tower of Pisa, trying to cut the bottom straight.
Upside down, and five minutes drying time, what a waste of time ...
Playing time..
How should I describe the sound then?
WOW, I'm stuck, feel a new addiction coming
Of course they do not rattle any windows, but there are enough bass so that's really fun to listen to Vicious Delicious by Infected Mushroom.
But they need not be ashamed when they play Ohio by Over The Rhine or Joy to my soul by Oslo Gospel Choir.
Oh sorry picture of speakers used..
The NS3 is running full range, the Vifa tweeters are not connected.
Already having some ides for the next build. Only have to find a store that sells foam board cheap.
\M
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Thanks, thickness is on front and back 10mm (3/8 inch) and sides in 5mm (3/16) in stores you can also buy 3mm (1/8).
But they are quite expensive, to bad.
\ \M
Actually I haven't any clue, it is sold as foam core board, in the store I bought it in.
I will try to take a picture of it. But it looks like the pictures on Google when I search for it.
It is /thick paper/ foam /thin paper / foam/ thick paper.
\\M
Guess it is your fault I'm bitten,Mag,
Nicely done! Finally someone with a big foam project. I bet it sounds great.
Love it. I see the bug has bitten you now. Isn't it great to not have any sawdust and you built it in your living room in what? An hour?!
X
ThanksTook a little more than a hour, slow drying glue.....
\\M