Hi as per title, I need to find some full range speakers for a boombox. Something fairly cheap would be preferable. I am also open to suggestions separate woofers/tweeters if you think that would be better and still affordable.
Stuff I already have -
2x 12AH 12V SLA batteries
Arjen Helder TA2020 2x25W amp (wasnt really planning on using it)
Sure Electronics TK2050 2x100W amp
Massive sheet of 12mm MDF
I would just like a fairly simple sealed or ported box, doesn't really matter how big it is.
Would like decent bass say 40Hz up. 20Hz is unrealistic yeah?
Would prefer drivers from an Australian store but have a package forwarding service I can use in the USA if that will work out better. Thanks.
Stuff I already have -
2x 12AH 12V SLA batteries
Arjen Helder TA2020 2x25W amp (wasnt really planning on using it)
Sure Electronics TK2050 2x100W amp
Massive sheet of 12mm MDF
I would just like a fairly simple sealed or ported box, doesn't really matter how big it is.
Would like decent bass say 40Hz up. 20Hz is unrealistic yeah?
Would prefer drivers from an Australian store but have a package forwarding service I can use in the USA if that will work out better. Thanks.
The Dayton ND105's have outstanding bass output for such a small driver.
Dayton Audio ND105-4 4" Aluminum Cone Midbass Driver 4 Ohm
These would work very well crossed with a helper tweeter.
There's a discussion on their forums with crossover diagrams.
on Sale - $55/pr (drivers & XO) - Techtalk Speaker Building, Audio, Video, and Electronics Customer Discussion Forum From Parts-Express.com
Dayton Audio ND105-4 4" Aluminum Cone Midbass Driver 4 Ohm
These would work very well crossed with a helper tweeter.
There's a discussion on their forums with crossover diagrams.
on Sale - $55/pr (drivers & XO) - Techtalk Speaker Building, Audio, Video, and Electronics Customer Discussion Forum From Parts-Express.com
So what you think I should run 2 of those 4" in series or something? They are a little low in the power department, 30W RMS each. I have a 100W per channel amp. Was hoping for something louder.. That second link seems to indicate they wouldnt be very loud.
Not even with 8" inch drivers? Those Dayton 4" seem to model OK down to 40Hz in a vented enclosure, then again I might not know what I'm doing. -3db is 35Hz
What about two of these in parallel for each channel - GRS 8FR-8 Full-Range 8" Speaker Pioneer Type B20FU20-51FW
Maybe coupled with a cheap tweeter to fill in the high end.
That would give 4ohms so I would get ~100W and they should handle the power. Efficiency is listed as 91dB 1W/1M
Volume could be anywhere in 60-120 L range.. (if I'm using WinISD correctly and not misinterpreting the graph its giving me)
Maybe coupled with a cheap tweeter to fill in the high end.
That would give 4ohms so I would get ~100W and they should handle the power. Efficiency is listed as 91dB 1W/1M
Volume could be anywhere in 60-120 L range.. (if I'm using WinISD correctly and not misinterpreting the graph its giving me)
I dont really care haha, as long as its mildly portable. Was thinking a longer enclosure that sat on the ground rather than a tall standing one.
Yea exaclty. Think center channel speaker. There are quite a few examples of center channel speakers covering lower frequencies (somewhere).
A boombox is mostly for outdoors use right?
If so remember to add the 6 dB/oct drop below 200Hz, so that -3 dB @ 35Hz is actually -18 dB (or -15 dB actually since it'll probably stand on the ground).
Even with 4 10" drivers my Boominator (over in the class-D forum) doesn't pressume to go below about 90Hz flat (F0).
Yeah it is mainly for outdoor, will get used a bit indoors too.
I didnt know about the 6 db/oct drop thing. Does that mean the frequency response curve would be better off peaking below the 200Hz mark so it would then get flattened out?
What are peoples thoughts on the GRS 8FR-8?
The GRS is probably more than good enough for your purpose. I dont' even think you'll need a tweeter. Treble has a way of getting sucked up into open air anyway. It's probably going to be used either far away in a 360 or 180 range or quite near field, right? No tweeter needed then.
Go for four GRS, in bipole config. That will give you plenty of slam and good spread of the higher frequencies.
With 12 mm mdf you want to either double up or put braces everywhere, not only for the sound quality but more so for long term structural integrity. Mdf, esp. without laminate is not a very strong material a portable box that is going to flex and bump around.
Go for four GRS, in bipole config. That will give you plenty of slam and good spread of the higher frequencies.
With 12 mm mdf you want to either double up or put braces everywhere, not only for the sound quality but more so for long term structural integrity. Mdf, esp. without laminate is not a very strong material a portable box that is going to flex and bump around.
Maybe I will just go for the GRS, I'm not after sound quality really anyway. Its more about being efficient, bassy and loud.
In bipole the speakers are supposed to be in phase, is there anything special I need to do to achieve this? I guess I just wire the two speakers per side in parallel to give me 4ohms?
Thanks for the construction tips. Should I make the sides point up slightly on a angle or just make it with vertical sides?
If you don't care about stereo (you probably don't in this case. It's probably never going to be noticed anyway) you can probably gain some efficiency by hooking the drivers up in an 8 ohm parallel-serial-parallel config.
But yes, bipole is just speakers wired in phase.
About the construction, what I'd do is wrap the whole thing in protective speaker felt (self-adhesive or spray glued), that stuff used for PA systems, put speaker corners on, also used in PA stuff, metal grilles of course and top the whole thing off with a PA handle. That will get you a rugged, prolooking box with minimal amount of work.
Monacor has quite a descent cheap selection of such stuff.
Monacor: Produkter
But yes, bipole is just speakers wired in phase.
About the construction, what I'd do is wrap the whole thing in protective speaker felt (self-adhesive or spray glued), that stuff used for PA systems, put speaker corners on, also used in PA stuff, metal grilles of course and top the whole thing off with a PA handle. That will get you a rugged, prolooking box with minimal amount of work.
Monacor has quite a descent cheap selection of such stuff.
Monacor: Produkter
I'm pretty sure I cant bridge the channels of the TK2050 so I cant run it in that config.
Yeah I was going to add some of that stuff, grills are a must.
I just checked the postage for 4x GRS speakers and its about US$120 which sucks.. but if there isnt a better option than thats what I'll go for.
Yeah I was going to add some of that stuff, grills are a must.
I just checked the postage for 4x GRS speakers and its about US$120 which sucks.. but if there isnt a better option than thats what I'll go for.
Actually again, Monacor is a good bet then. They have some pretty good efficient drivers for low prices. Otherwise if you don't have that brand in Aus. then do a bit of searching. Visaton and Vifa springs to mind as other likely candidates. Pioneer Bofu/GRS is just hot in the US because that's what they got there. Similar drivers are available in other territories.
I'm pretty sure you can make the amp output a combined monosignal. It doesn't care what it's outputting as long as long as it's not shorting anything or presenting it to too little resistance.
I'm pretty sure you can make the amp output a combined monosignal. It doesn't care what it's outputting as long as long as it's not shorting anything or presenting it to too little resistance.
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Can someone please check over these box calculations from WinISD.
Speaker parameters are here if you want to check i entered the parameters correctly.
Does that look right? 73.2L with 34.77Hz tuning and a 10cm port that is 20cm long. Last thing I want to do is build a box that is totally wrong.
An externally hosted image should be here but it was not working when we last tested it.
Speaker parameters are here if you want to check i entered the parameters correctly.
Does that look right? 73.2L with 34.77Hz tuning and a 10cm port that is 20cm long. Last thing I want to do is build a box that is totally wrong.
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