Fast, fun, Inexpensive OB project

Could somebody explain to me what happened?-

I have the manzanita 12" with vifa. I had originally wired the vifa opposite polarity for more 'relaxed' sound, and then when i tilted the baffle back 30degrees yestetday, i had to rewire to vifa to its original polarity because the reverse polarity was no longer the more 'relaxed' configuration. It sounds less shouty with both + polarities together now.

Why is this so?

Thank you for the education :)
 
Hello all, I am rebuilding these as when I moved a couple of years ago, my listening space wasn't ideal. I repurposed the 12in sls into a Ripole subwoofer and errr... used the baffles as kindling as they weren't particularly pretty. I have moved again and am missing that open baffle sound and am now rebuilding the baffles and have the original 12in Peerless sls drivers and the Seas 27tdfc tweeters. From what I understand, the Vifa is superior but this is what I have and what I'll use for now. My question is the pictures on the first page for the baffle have been revised (iirc the original baffle was different and I see that it mentions the Vifa. Is the crossover schematic also revised or is that the crossover schematic for the original drivers? If it isn't, can someone point me to a pic of the original cross-over?
Thanks,
Andre
 
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I'll dig thru my archives to see if I still have the original crossover - it's been awhile.
Don't hesitate to get the Vifa/Peerless TC9FD as it's inexpensive and works better for this speaker than the original tweeter. I buy mine from Parts Express, but you might have another source north of the border.
 
I'm glad this thread has found new life! It's inspired me to whip up a Manzanita-like pair of tabletop OB speakers using some drivers I have on hand, namely an old Focal 13v7511 12"/13" woofer and the Peerless TG9 fullrange. I'm using a thin baffle (1/4" MDF) of minimal size, so that the frame of the woofer is really supporting and stiffening much of the baffle. Another MDF cradle will support the magnet of the Focal to make the structure more stable. I'm also planning to rear-mounting the TG9. I will work this up as an active speaker, so I think I will call it the "active Charlita" as a way to pay some small homage to the original Manzanita.

Just cut the baffles today but I may not get to assembling them for another week or so unless I find some time and space for it while I work on other projects.
 
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Well I found a schematic, but I had just labeled it M-12 crossover. :xeye: Not really sure this is correct. John should remember.
EDIT: I found the BOM from 10 years ago, and this would be it. This matches the parts used with the 27TDFC.
 

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Interesting how the parts prices have changed over the past 10 years.
  • Peerless 830669 woofer___2007 - $71.65__2017 - $76.99
  • SEAS 27TDFC tweeter____2007 - $35.13__2017 - $47.10
  • Sledgehammer 12mH____2007 - $21.75__2017 - $32.00
  • Aircore 0.81mH coil______2007 - $4.20___2017 - $5.70
  • Film Cap 12uF__________2007 - $5.40___2017 - $7.00
 
Very good! Looking forward to photos and reports of how well it works. :up:

I managed to throw together one speaker tonight. I won't be able to get to taking measurements and working up the crossover for at least another week, but this gives you an idea of how its put together. Minimal 14x17 baffle using 1/4" (6mm) thick MDF. My lungs are still clogged with the stuff. :( The woofer frame adds stiffness to the thin baffle. The TG9 is rear mounted because the windows in the frame are pretty small and I do not want to impede the rearward radiation. I will probably need to do some extensive chamfering of the edges of the hole to minimize a tunnel resonance that will otherwise appear probably somewhere around 1.5kHz.

A cradle/"kickstand" holds up the magnet of the woofer. This can work but I will need to firmly attach it (glue/screw?) to the bottom edge of the baffle. Might also try to add some mass behind the magnet to reduce vibration/movement. It's pie in the sky at this point but that's the general direction of the project at this point.

Sorry for the poor pic quality. Lighting at the time was poor.
 

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