Howdy folks. I built a set of TG's Faital 3wc 15" at the start of the year. This gave me a taste for DIY. I'm half way through building a set of micro active 2 way speakers for my son to use with his electric drum kit, and for general use (and maybe to take when we travel).
Figured i'd post it up here in case anyone has helpful comments, or wants to build something similar and my build helps.
Am using:
Wondom Jab5 (4 x 100w with DSP) - will use 1 channel per driver
SBA SB19ST 4 ohm tweeters
Dayton ND105 4 ohm 4" woofers
16mm MDF cabinets at 4.5L internal
Planning to muck around a bit with the DSP to see how low i can get them to go with a flat response.
My thinking is the amp's good for 100wpc, the drivers are 30w, so call it 60w peak. The amp's meant to be ok to 6 ohms, i'm asking it to deal with 4 ohms, but hopefully the fact that it's quite overpowered for the drivers means nothing melts.
Have cut everything, and done a basic test of the amp last night to ensure it works:
Wondom Jab5 test - YouTube
Next up bench test using the PC control module and all 4 drivers.
After that i need to mount the hardware in the cabinet. The 1 job i need to work out is how to have the plugs mounted, the 16mm MDF is too thick. I could rout it, but then it might be too thin. Do i use some hard plastic, or can i use metal - but i'm concerned about having a power plug mounted directly to metal... I'm not electrically skilled.
Few pics of the build so far:
Figured i'd post it up here in case anyone has helpful comments, or wants to build something similar and my build helps.
Am using:
Wondom Jab5 (4 x 100w with DSP) - will use 1 channel per driver
SBA SB19ST 4 ohm tweeters
Dayton ND105 4 ohm 4" woofers
16mm MDF cabinets at 4.5L internal
Planning to muck around a bit with the DSP to see how low i can get them to go with a flat response.
My thinking is the amp's good for 100wpc, the drivers are 30w, so call it 60w peak. The amp's meant to be ok to 6 ohms, i'm asking it to deal with 4 ohms, but hopefully the fact that it's quite overpowered for the drivers means nothing melts.
Have cut everything, and done a basic test of the amp last night to ensure it works:
Wondom Jab5 test - YouTube
Next up bench test using the PC control module and all 4 drivers.
After that i need to mount the hardware in the cabinet. The 1 job i need to work out is how to have the plugs mounted, the 16mm MDF is too thick. I could rout it, but then it might be too thin. Do i use some hard plastic, or can i use metal - but i'm concerned about having a power plug mounted directly to metal... I'm not electrically skilled.
Few pics of the build so far:
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Interesting project, you've done some nice work.
It's possible that you'll luck out here, but the logic you have used is not correct. Go slowly.
You should be concerned. Note that if your house burns down and your insurance company finds incorrect work you will have a problem.
Thanks Allen.
Yeah, the metal plate idea was no good. I'll have to find something else, maybe some very thin hardwood.
I've received advice from an electrical engineer at work that i'll "probably" be ok with the amp/driver combo.
Worst case i have to swap the drivers out for something 8 ohm, i went with 4 as they were more readily available and modelling had a lower frequency range than 8 ohm equivalents.
Anyway it's mostly just a learning experience, hopefully it pans out ok.
Thanks for the comments
Yeah, the metal plate idea was no good. I'll have to find something else, maybe some very thin hardwood.
I've received advice from an electrical engineer at work that i'll "probably" be ok with the amp/driver combo.
Worst case i have to swap the drivers out for something 8 ohm, i went with 4 as they were more readily available and modelling had a lower frequency range than 8 ohm equivalents.
Anyway it's mostly just a learning experience, hopefully it pans out ok.
Thanks for the comments
A metal plate may actually be compulsory. This isn't clear yet from what you've said, but I'm a little nervous myself about advising someone who is unlicensed, about mains wiring. At the least could you begin with some research on appliance classes and electrical safety.. and if this is nothing more than a learning experience then you could always find pre-enclosed power supplies to work with
They wont be mains wired, i'll be connecting a 19.5v laptop charger to the speaker box by plug. Given the impedance of the drivers, i'll see how that goes as i may need to look for a higher voltage charger instead if the amp's getting too hot. (Wondom state the amp can take up to 39v i think).
also on their website people have asked about running 4 ohm drivers, and they say it's possible, so at least there's no auto shutoff if the impedance drops too much..
Will do some board testing for temperatures with all 4 drives connected to see how hot it gets.
also on their website people have asked about running 4 ohm drivers, and they say it's possible, so at least there's no auto shutoff if the impedance drops too much..
Will do some board testing for temperatures with all 4 drives connected to see how hot it gets.
Other stuff readily (locally) available:
Digikey. The Tymphany / Peerless drivers are good value, and orders over $60 have free postage. Note that you need to filter by "in stock" stuff. Non stock stuff has a big delay / minimum order.
WES components and a couple of other places are also local, but usually cost a bit more.
...and there is always 2nd hand and salvage.
In a DSP build, you can make any driver play low. The limit is typically the driver displacement.
Great idea.
Hi mate, yep the amp seems to be handling the 4 ohm load ok, i ran them for a few hours yesterday and it barely warmed up..
Tweeter is too bright as expected, it's a couple of db more efficient than the woofer..
The trouble i'm having at present is SigmaStudio - I can't get sound from the amp while tuning, however once i connect the ICP1 control module, the amp wont play anything (by either bluetooth or the 3.5mm jack i've installed.
Anyway fun fun, lots to learn now with REW and SigmaStudio..
Another plus with buying a Dayton UMM 6 measurement mic is i can measure my main speakers for fun (Troel's Gravesen Faital 3wc 15"). Good way to get more practice with REW.
Tweeter is too bright as expected, it's a couple of db more efficient than the woofer..
The trouble i'm having at present is SigmaStudio - I can't get sound from the amp while tuning, however once i connect the ICP1 control module, the amp wont play anything (by either bluetooth or the 3.5mm jack i've installed.
Anyway fun fun, lots to learn now with REW and SigmaStudio..
Another plus with buying a Dayton UMM 6 measurement mic is i can measure my main speakers for fun (Troel's Gravesen Faital 3wc 15"). Good way to get more practice with REW.
