s.o.u.p! 0 Posted September 17, 2008 I have a few speakers I'd like to play with and make a new pair. in each box I'll have 2 X 8" 1 X 2" and 1 X .5" There will be a slight problem however with the 8" woofers being 8ohms each, making for a 4ohms or 16ohms configuration. Unless I have a 4 way system, which poses some unique oppertunities aswell. I'm not really sure on the box configuration though, sealed, ported, transmission line..... other. I currently have a pair of transmission lines with 1 X 8" and 1 X 1" each, and a tight taper of 1.1. I'm capable of handling and not afraid of a challenge, anything is on the table, I don't want something I can just knock up in a day, I'm out to challenge myself and impress. So, what would you guys like to see? Or what do you reckon? And what would you do about the woofers? I'm really thinking about something with a 3rd order bypass subwoofer and a filter I know of that incorporates a lightbulb that will grow brighter based on signal strength, and a glass window into the enclosure that will allow the view of the woofer. I havn't done much in the way of drawing this yet, but I will if my plans go further and nobody comes up with an idea that I like better, but the box would be rather tall with the following order of componants in the following order.... .5" tweter 2" midrange 8" woofer Plinth Window with view of angled 8" woofer Plinth I'm guessing about 4~5 ft tall, a foot deep and a foot wide. But nothing is set yet, including the design. Later if neccessary I'll link to the speakers I'll be using, but I'm happy to do that groundwork if someone comes up with a design I like better. This is NOT a project you'll be reading about in the upcoming weeks/months this is just a spark and I'll be putting in more effort when my timetable clears more..... Share this post Link to post Share on other sites
datafast69 68 Posted September 17, 2008 Hmm...cab's hay :) How about something in petrified wood :D Should have a low resonance? Maybe? You could maybe do a sealed bottom with the two 8" drivers and a ported top, in a slightly rear leaning pyramid style...damn I don't know :P For a little inspiration ;) http://www.humblehomemadehifi.com/Andromeda.html Share this post Link to post Share on other sites
kRaZeD_ 0 Posted September 17, 2008 Expanding on datafasts idea... Do a ported lower 8" then a sealed 8" above it, one for the lower end and one for tighter lower midbass. Might sound like poop, but it might not too. Share this post Link to post Share on other sites
maccdaddy 0 Posted September 17, 2008 Expanding on datafasts idea... Do a ported lower 8" then a sealed 8" above it, one for the lower end and one for tighter lower midbass. Might sound like poop, but it might not too. Haha that's a cool idea, depends on the suitability of the speakers too though. There is still the problem of the impedance... Share this post Link to post Share on other sites
datafast69 68 Posted September 17, 2008 Yeah, looking at my suggestions I'm very sure that I'm not a speaker designer :P The big question is, are the drivers suited to work well together, you don't want to have any driver stressing to reach the crossover point to the next. Share this post Link to post Share on other sites
maccdaddy 0 Posted September 17, 2008 Yeah, looking at my suggestions I'm very sure that I'm not a speaker designer :P The big question is, are the drivers suited to work well together, you don't want to have any driver stressing to reach the crossover point to the next. That's a good point, you would need to filter the ported driver to a lower frequency and HP the sealed one a bit higher otherwise it will sound shite. Share this post Link to post Share on other sites
kRaZeD_ 0 Posted September 17, 2008 Yeah, looking at my suggestions I'm very sure that I'm not a speaker designer :P The big question is, are the drivers suited to work well together, you don't want to have any driver stressing to reach the crossover point to the next. That's a good point, you would need to filter the ported driver to a lower frequency and HP the sealed one a bit higher otherwise it will sound shite. Good luck finding a crossover design with suitable points for that idea... Share this post Link to post Share on other sites
maccdaddy 0 Posted September 17, 2008 Yeah, looking at my suggestions I'm very sure that I'm not a speaker designer :P The big question is, are the drivers suited to work well together, you don't want to have any driver stressing to reach the crossover point to the next. That's a good point, you would need to filter the ported driver to a lower frequency and HP the sealed one a bit higher otherwise it will sound shite. Good luck finding a crossover design with suitable points for that idea... Wait, he never said he wanted an easy solution... He could custom build his own crossover, it may take a few years doing an electrical engineering degree but that's the challenge :P Share this post Link to post Share on other sites
Burning_Feet_Man 0 Posted September 17, 2008 8" ported, 6.5" sealed mid, 1" tweeter + ribbon avoid the window Share this post Link to post Share on other sites
wheelz 0 Posted September 17, 2008 8" ported, 6.5" sealed mid, 1" tweeter + ribbon avoid the window +1 on that suggestion. Theres not much chance of getting 2 x 8's to blend with 1 x 2 inch midrange. 8's play horribly above 1.6- 2k and 2 of them will slighty amplify that issue, and 2 inch midranges wont play much below 3k with any decency. That leaves a nasty octave sized gap. 8 in ported for nice low end extension, should play down to 40ish nicely, 6.5in midbass/midrange, and some 1 inch tweets. the fun part is getting the crossovers right. they need to suit the actual drivers themselves and are tricky to design. Share this post Link to post Share on other sites
s.o.u.p! 0 Posted September 19, 2008 What's wrong with a window? Crosovers are easy, to make, well, passive ones anyway, series, parrallell, high pass, low pass, attenuator circuits, all good in that department. (With most speakers) The 4th order bandpass sub box tipycally has a nice high end rolloff that matches the low end rolloff of a sealed that has the same model speaker. so it doesn't matter if they are 4 ohms, 16 ohms, or 8 ohms each because if they're 8 ohms, you can just use a crossover, and if they aren't 8 ohms each you can just wire the woofers in parrallell/series and let the box's natural rolloff handle the bandpassing. For the lowest rolloff though the ported wins out (atleast with this model speaker) but the box will be bigger and the appearance of the box will be more plain (than the 4th order bandpass configuration). But the ported will have a morelinear delay at the crossover frequency (85~100 hz) (the 4th order bandpass box will have a large delay at the frequency of 85hz) The delay can be removed with the plinth design tough, and that could make for an interesting box. As for the midrange, turns out I don't have them, and can't get them anymore, so maybe a sealed 4", but I still like these 2" ones I originally thought I had, because they looked cool and have a very wide frequency response range. Share this post Link to post Share on other sites
s.o.u.p! 0 Posted September 19, 2008 8" woofer: 8 ohms 120W RMS 90db @ 1W 1M Re 6.9 ohms fs 39.9hz Qms 6.623 Qts 0.470 Qes 0.506 Vas 32.8L Cone area 0.0214 Share this post Link to post Share on other sites
kRaZeD_ 0 Posted September 19, 2008 Jaycar 8" from a few years ago? Format seems to suggest so :) Share this post Link to post Share on other sites
s.o.u.p! 0 Posted September 19, 2008 Yeah, I got them for one purpose, then used them for another, and now their garage fodder, so I wanna make them into something worth it. Share this post Link to post Share on other sites
battlefield_gir 1 Posted September 20, 2008 this is felipes domain. im also making speakers. god damnd finnish drivers are so expensive but sound fantasic. Share this post Link to post Share on other sites