Yeah would definitely say start w/ 2 way. XO is by far the hardest thing to get right in audio (for me anyway). My first build was 2 x 8's and a cheap motorola horn.
Not great speakers and not great working with each other but I know that now! Rebuilt that XO sooooo many times and that helped me understand audio way more than most anything else I've done. Crack into it, get to test lots of configurations and discover what sounds good to you. Even once you know what your doing much of a build is compromise. You get to choose one characteristic over another. This has all lead me to my current build, tri-amp 3 way w/ active XO, phase perfection!
Not great speakers and not great working with each other but I know that now! Rebuilt that XO sooooo many times and that helped me understand audio way more than most anything else I've done. Crack into it, get to test lots of configurations and discover what sounds good to you. Even once you know what your doing much of a build is compromise. You get to choose one characteristic over another. This has all lead me to my current build, tri-amp 3 way w/ active XO, phase perfection!
Alright, I'll talk to my dad and brother about building the BOFU tonight. If the build gets commenced, I'll be sure to post back with pictures and the like 
No promises that it'll look amazing, but hopefully we'll get a working speaker. Thanks again everyone who contributed and helped me make a decision
Just out of curiosity, I see that the tweeter handles 10W RMS and the woofer handles 60W RMS. Does that mean the speaker will handle 70W RMS total?
No promises that it'll look amazing, but hopefully we'll get a working speaker. Thanks again everyone who contributed and helped me make a decision Just out of curiosity, I see that the tweeter handles 10W RMS and the woofer handles 60W RMS. Does that mean the speaker will handle 70W RMS total?
60 watts continuous sinewave can burn out large voice coils - think about holding your hand on a 60 watt incandescent light bulb only worse - or a holding a 15 watt soldering iron tip - - music has peak to average dB levels - some pop music has very little dynamics. There's less energy in the highs overall. Under hard drive, speakers coils will heat, that raises their Re and qts. You need enough power not to clip too often for your listening requirements. BOFU to my ears has a "shimmering" compressed sound which is euphonic. The Sammi is less sweet but has stronger motor and can play louder without as much compression - either were fun in the klam toy outdoors. re:grout sealer - is silicone type to be avoided? - or do any them extend foam surround life?
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Ah, yeah I just asked out of curiosity. I don't plan on blasting them 24/7, so that won't be a problem then.
I have some 25+ year old speakers that were sealed with silicone, and they've had absolutely no problems. Still sealed and sounding good It looks a little sloppy if you don't cut off the excess, but it should be fine. I'm not sure if it's the best, but I'm just posting what worked for those.
I have some 25+ year old speakers that were sealed with silicone, and they've had absolutely no problems. Still sealed and sounding good
It looks a little sloppy if you don't cut off the excess, but it should be fine. I'm not sure if it's the best, but I'm just posting what worked for those.
>>> Rebuilt that XO sooooo many times...
Yup. Seeing that big piezo horn in the pic above made me laugh. I built something recently using that tweeter (the cheap version from PE anyway) and had a difficult time coming to grips with it... let me find a pic to post... it's a very cute looking little speaker but BOY DID IT GIVE ME A HEADACHE! I think i used a 3.3uf cap on the tweeter (and a 20 ohm resistor across) and let the woofer (a 5.5" Jamo buyout also from PE) run full. The woofer has a full, rich sound and looked well made, especially for around $10!). It's an easy first timer project. But the treble always stunk! I may have posted before that that tweeter NEEDS a helper tweeter. The smaller piezos sound much better to me and are far easier to integrate using smaller caps with full/wide range speakers. Allowing piezos to cross over too low never sounds good imo. If you use that large piezo, completely covering the back with plumbers putty... probably even silly putty... made it sound better by reducing the plasticy sound it has. I have two left and wanted to use them for something else but have decided to leave them for another day. I gave these little black speakers away to my friends ex wife since he got the stereo and she needed something... he bought her a cheap receiver and set up the speakers so she can enjoy her music. I think they suit the dance music she listens to... I've been told she loves the speakers. I would rather use them as small tables instead of for music.
The lemon squeezer tweeter and the other small piezos work great imo with the B20 with simply a 20 ohm resistor across and a cap value between .33 an 1.5uf... i have mine setup firing backwards using a 1uf cap and an Lpad... firing forward i use a .47uf cap (8ohm resistor across) and no Lpad. I'm happy with that but understand others might like something different.
I have been eyeing that 4" dayton driver for weeks now. It's on my 'to buy' list and i was going to post a design of it paired with a small cheap piezo to make a neat little dorm speaker that works with an inexpensive receiver or maybe the dayton digital amp... if it can move that woofer LOL... If anyone wants to build it before i do i simmed a .375cf box with a 1" x 1.5" port for a -3 at 42hz... have not figured the piezo cap and resistor value yet but i'm pretty sure it will all work well together.
Godzilla
Yup. Seeing that big piezo horn in the pic above made me laugh. I built something recently using that tweeter (the cheap version from PE anyway) and had a difficult time coming to grips with it... let me find a pic to post... it's a very cute looking little speaker but BOY DID IT GIVE ME A HEADACHE! I think i used a 3.3uf cap on the tweeter (and a 20 ohm resistor across) and let the woofer (a 5.5" Jamo buyout also from PE) run full. The woofer has a full, rich sound and looked well made, especially for around $10!). It's an easy first timer project. But the treble always stunk! I may have posted before that that tweeter NEEDS a helper tweeter. The smaller piezos sound much better to me and are far easier to integrate using smaller caps with full/wide range speakers. Allowing piezos to cross over too low never sounds good imo. If you use that large piezo, completely covering the back with plumbers putty... probably even silly putty... made it sound better by reducing the plasticy sound it has. I have two left and wanted to use them for something else but have decided to leave them for another day. I gave these little black speakers away to my friends ex wife since he got the stereo and she needed something... he bought her a cheap receiver and set up the speakers so she can enjoy her music. I think they suit the dance music she listens to... I've been told she loves the speakers. I would rather use them as small tables instead of for music.
The lemon squeezer tweeter and the other small piezos work great imo with the B20 with simply a 20 ohm resistor across and a cap value between .33 an 1.5uf... i have mine setup firing backwards using a 1uf cap and an Lpad... firing forward i use a .47uf cap (8ohm resistor across) and no Lpad. I'm happy with that but understand others might like something different.
I have been eyeing that 4" dayton driver for weeks now. It's on my 'to buy' list and i was going to post a design of it paired with a small cheap piezo to make a neat little dorm speaker that works with an inexpensive receiver or maybe the dayton digital amp... if it can move that woofer LOL... If anyone wants to build it before i do i simmed a .375cf box with a 1" x 1.5" port for a -3 at 42hz... have not figured the piezo cap and resistor value yet but i'm pretty sure it will all work well together.
Godzilla
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That XO is kinda low... <2.5kHz by my calc. The official Motorola version of this piezo is nice.
dave
>>> That XO is kinda low...
Yup. But the speaker sounded like it had a hole in the mids if i went higher... it may have been a 2.2uf cap lol... but no matter what i did, it was no Fostex! No one should use those parts that i did to build that speaker. Perhaps both of those drivers could be put to better use in a totally different configuration with totally different drivers with success. Listening to better quality full range drivers from Fostex and Tang Band have caressed my ears these past few years with lovely sonics... all the more reason DIYers should give them a try over two way crap. But i'm preaching to the choir now.
Yup. But the speaker sounded like it had a hole in the mids if i went higher... it may have been a 2.2uf cap lol... but no matter what i did, it was no Fostex! No one should use those parts that i did to build that speaker. Perhaps both of those drivers could be put to better use in a totally different configuration with totally different drivers with success. Listening to better quality full range drivers from Fostex and Tang Band have caressed my ears these past few years with lovely sonics... all the more reason DIYers should give them a try over two way crap. But i'm preaching to the choir now.
even 2uF/8R parallel with 1016 is awfully low and has that bump which may need to be considered (not sure how close 1005 is to 1016 on the bottom). (off axis larger fullrange are rolling off and will exhibit big power holes in response - that 4-5K peak might do some crude filling) Normally its good practice with piezo to use 56R series after the parallel loading resistor - dunno if the near-short at VHF ever causes any real problems with some amps (?)
An externally hosted image should be here but it was not working when we last tested it.
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Thanks for the frequency chart... the large piezo sounded like the chart looks... yuck! The Jamo driver i used with it is rated to 4k... i have a feeling it does not make it that high and that's why i kept reaching lower with the big piezo... a dome with response comfortable to 2k is probably a better bet with the Jamo closeouts.
http://www.parts-express.com/pe/showdetl.cfm?Partnumber=272-302
http://www.parts-express.com/pe/showdetl.cfm?Partnumber=299-935
http://www.parts-express.com/pe/showdetl.cfm?Partnumber=272-302
http://www.parts-express.com/pe/showdetl.cfm?Partnumber=299-935
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Have you actually given us your budget??
I usually work on equal thirds when budgeting for speakers.
1/3 drivers
1/3 XO
1/3 box
Fungible depending on circumstances and what I can scrounge or salvage, which is why garage sales and thrift shops can ge your friend.
As an aside, Dave, how do you think would my earlier suggestion of a Foster full-range with a point 5 woofer sound?? Personally I would prefer a bigger woofer 8 or 10 inches but that little Peerless was reasonably priced and easy to deal with.
Zilla - IIRC KSN1005 was about as peaky on the bottom as KSN1016A - some copies of CTS are even funkier - here's a page showing 1005 without and with a network to flatten its response. If I ever hookup a measurement system again I'll check 1005 with CL feeding the piezo with resistor - that seemed to have promise - but the corner was still too low - might take a few minutes piddling
I ran this in the fake Druid
Piezo measurements
I ran this in the fake Druid
An externally hosted image should be here but it was not working when we last tested it.
Piezo measurements
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It is a bit tricky to get something other than exactly the same to work in a 0.5 configuration... often simplier to just go FAST.
It is something i have considered but not tried... usually when i'm looking at a set of the BD pipes or another bipole and asking myself if i can sub a little woofer in instead of another FR.
dave
I guess just the minimum it would cost to build a speaker. I may not put it in a full enclosure, as I'm really interested in just building a working speaker and understanding everything before I go through building good speakers. I'd like to spend no more than $50 on the drivers and the XO's, but the less I have to spend, the better. I only plan on building one speaker ATM. If I really like the way this BOFU sounds, I'll go out and buy some better enclosure materials.
Check the Speaker Gallery at Tech Talk at Parts Express. There many different inexpensive good sounding designs. Same for the Project showcase on Parts Express.
It was such a common Japanese approach in the early days too, I guess I've been lucky then.
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