Hi, Newbie on this forum and the DIY scene.
I am hoping for some advice. I am a stickler on recycling stuff in my house.
I have a coffee table shaped like a cabinate 720x220x400mm (63liters). a pair of EMU-XM7 (2way -5") (i know i am committing a sin) and a 6.5" Yamaha midbass woofer, powered by an Arylic 2.1 amp.
I want to put all these into the exclosure and know i will be sacrificing stereo.
I have tried to use the cabinate calculator but it has totally confused me and wonder if anyone here can advise me.
1) Is the enclosure too big?
2) Do i need a vent?
3) Should i enclose the 5" and the tweeter?
4) Should i build a seperate enclosure for the 6.5" ? and vent ?
I plan to use the cross-over from the EMU-XM7 for the 5" and tweeter.. and use the subwoofer function from the arylic2.1 to drive the 6.5".
Any feedback will be appreciated! thanks again guys. This is a place full of information though confusing for a newb. 🙂
Here is the ideas of the layout.
Screenshot 2021-05-12 013213.jpg - Google Drive
I am hoping for some advice. I am a stickler on recycling stuff in my house.
I have a coffee table shaped like a cabinate 720x220x400mm (63liters). a pair of EMU-XM7 (2way -5") (i know i am committing a sin) and a 6.5" Yamaha midbass woofer, powered by an Arylic 2.1 amp.
I want to put all these into the exclosure and know i will be sacrificing stereo.
I have tried to use the cabinate calculator but it has totally confused me and wonder if anyone here can advise me.
1) Is the enclosure too big?
2) Do i need a vent?
3) Should i enclose the 5" and the tweeter?
4) Should i build a seperate enclosure for the 6.5" ? and vent ?
I plan to use the cross-over from the EMU-XM7 for the 5" and tweeter.. and use the subwoofer function from the arylic2.1 to drive the 6.5".
Any feedback will be appreciated! thanks again guys. This is a place full of information though confusing for a newb. 🙂
Here is the ideas of the layout.
Screenshot 2021-05-12 013213.jpg - Google Drive
An externally hosted image should be here but it was not working when we last tested it.
Welcome, kerv, I'll give your thread a nudge!
It's no wonder you are apologetic, as you are about to butcher a perfectly good pair of bookshelf speakers! 😱
E-MU XM7 Bookshelf Speakers - Perfect companion for the Sound Blaster X7 - Creative Labs (UK)
What is this cabinet calculator you have tried to use?
I would consider the possibility of giving the 5" drivers (plus tweeters) their own small, sealed enclosures within the larger "coffee table" cabinet.
The remaining cabinet volume would then be dedicated to the Yamaha 6.5" mid/bassdriver. Can you give its specifications to determine its suitability for such a role?
You need to download the datasheet on your 6.5" driver to find out qt, vas, fs, xmax
qt > .4 many suggest sealed cabinet. qt < .4 many suggest vented.
I have a datasheet on a 6.5" visiton bg17-8 and the vas is 8.2 L so with a box of 63 L David Weems suggest your resonant F3 is about 1.2* fs. For a ported box.
His chart for 5 cm ID ducts drops off at 60 L but the next entry up in the 40 hz table is 2.2 cm long.
I wouldn't put the 2nd 5" speaker in there, nor the first. Too close to the woofer to bother with. I would spend $3 on a 3" tweeter. You are going to have to buy a box of crossover parts anyway. FIll the box with useful things. My $99 (in 1977) KLH23 were a 10" woofer with a 3" paper cone tweeter, tweeter blocked by one capacitor. Sounded decent.
qt > .4 many suggest sealed cabinet. qt < .4 many suggest vented.
I have a datasheet on a 6.5" visiton bg17-8 and the vas is 8.2 L so with a box of 63 L David Weems suggest your resonant F3 is about 1.2* fs. For a ported box.
His chart for 5 cm ID ducts drops off at 60 L but the next entry up in the 40 hz table is 2.2 cm long.
I wouldn't put the 2nd 5" speaker in there, nor the first. Too close to the woofer to bother with. I would spend $3 on a 3" tweeter. You are going to have to buy a box of crossover parts anyway. FIll the box with useful things. My $99 (in 1977) KLH23 were a 10" woofer with a 3" paper cone tweeter, tweeter blocked by one capacitor. Sounded decent.
Last edited:
Thanks, i though that.. i did a quick stick together job today with plywood and bluetac. I would definately say it didnt sound good. 🙁 more of a boxy sound without a punch. (i have yet to put the tweeter and 5" into their own enclosure)
i have been trying to the the tech spec for the speakers but it seems impossible. (i have been searching for over a week on the web)
As you know the e-mu xm7 are creatives with not model number on them, whilst the yamaha is from a subwoofer YST-SW015 and the woofer model is X2323AO.
Hi indianajo,
problem is that the speakers are ripped out from other speakers so there isnt tech spec sheets around. the tweeter and 5" comes from creative E-MU XM7 and have no model number on them, whilst the yamaha (6.5")is from a subwoofer YST-SW015 and the woofer model is X2323AO.
Will try you suggestion later in the week, i just found another 6.5 yamaha speaker of the same model and will try sticking 2 $3 tweeter with 2 yamaha (6.5") .. Since i now have 2x6.5" do you think i will still need the vented ports and how able will i go doing it?
Thank!!
Since the T/S parameters of the subwoofer driver are not available, we can do little to help you.
The subwoofer driver is intended for a ported enclosure as photos of the original Yamaha subwoofer enclosure reveal.
Enclosures have to be built around known subwoofer paramenters. I'm afraid you cannot just stick any old subwoofer into an existing cabinet and expect it to perform properly.
An externally hosted image should be here but it was not working when we last tested it.
The subwoofer driver is intended for a ported enclosure as photos of the original Yamaha subwoofer enclosure reveal.
Enclosures have to be built around known subwoofer paramenters. I'm afraid you cannot just stick any old subwoofer into an existing cabinet and expect it to perform properly.
One possible cause of your bad sound of your quick box is internal reflections. Hard surfaces can cause standing waves at the frequency caused by the speed of sound and the dimensions of the box. People handle this by lining the box with absorbant or stuffing it with fiber. I intend to buy 1/2" thick jute carmat underlayment on ebay. Allegedly better than rubber underlayment available at all carpet stores. I intend to screw it inside the box in a double layer.
stuffing the box with fiber lowers the speed of sound overall and makes the box measure bigger than it is, so I am not going to do that. You had a box, a cabinet, that was nearly too big anyway for a 6 1/2" driver. I was trying to reuse a bit of furniture myself, 28"t x 29"w x 16" d. But bought 15" drivers from eminence to replace Peavey SP2-XT speakers that were stolen last September.
I've put 6.5" drivers on the end of a 8"x8"x14" carboard box with a 1" square hole in the other end. At 1 watt for TV sound the result was pleasant. Drivers were salvaged from a projection TV I found on the curb on garbage day.
Do you have a microphone to measure your result? Some software people quote is REM. I don't have Windows computer, so I am going to measure different frequencies with a fixed gain op amp & an analog VOM.
stuffing the box with fiber lowers the speed of sound overall and makes the box measure bigger than it is, so I am not going to do that. You had a box, a cabinet, that was nearly too big anyway for a 6 1/2" driver. I was trying to reuse a bit of furniture myself, 28"t x 29"w x 16" d. But bought 15" drivers from eminence to replace Peavey SP2-XT speakers that were stolen last September.
I've put 6.5" drivers on the end of a 8"x8"x14" carboard box with a 1" square hole in the other end. At 1 watt for TV sound the result was pleasant. Drivers were salvaged from a projection TV I found on the curb on garbage day.
Do you have a microphone to measure your result? Some software people quote is REM. I don't have Windows computer, so I am going to measure different frequencies with a fixed gain op amp & an analog VOM.
You said you intended to use a 2.1 amplifier, in which case the correct combination is subwoofer and two 'full-range' satellite speakers.
The woofer amplifier section of the 2.1 amp would drive the subwoofer and the stereo amplifier section would drive two, small, full range drivers - not tweeters.
A 6.5" driver plus a 3" tweeter, with a crossover, is a 2 way speaker. A 5" driver, even full range, is not going to get you much bass. I tend to think of subs as 200 hz & lower. Subs certainly are not stereo.
above 200 hz you get into human voice, which requires stereo for proper response.
HI thanks for you reply. 🙂 It great having ideas and advise instead of poking around blindly!!
Hmmm. i bought some fish tank filter that was suppose to dampen the reflection but i didnt think that it will increase the size of the box (which is already too big). Will head out to lok for rubber underlay to see if it will work.
Yeah i had a feeling that the box maybe too big but i am thinking IF i place 2 6.5" drivers it MIGHT do the trick? Hahaha.
@Galu mentioned that the drivers originally came from a box with a port. Thing is looking at the measurement its rought 1/2 the volume of mine. Do you think that not putting a port on mine would be good enough because of the volume (63ltrs)?
Hmmm.. dont have a mic.. but i saw somewhere i can jimmy up a mic and an aluminium tube for testing for under $10. (that will have to wait to the weekend).
Cant wait to see what happens!!
Seems we both have an idiosyncrasy on recycling stuff 🙂
Hey Galu🙂
thanks for your reply.
yeah i know.. but i am trying to recycle a:
1) coffee table
2) A pair of speakers (2way consisting tweeter and 5" mid woofer with x-over)
3) 1 (or 2) 6.5" Yamaha midbass wooofers.
I want to put it all into the coffee table. with no satelites 🙂 yeah i know its silly but its the challenge. 🙂
Understand.. thus i was thinking of pairing the 5" and tweeter.. and have the single 6.5" like in the photo is sent. 2.1 in one box with no stereo. 😛
Yes, kerv, the woofer section of your 2.1 amplifier is mono and reproduces only the bass frequencies below, say, 250Hz.
The remainder of the audible range (250Hz and above) is reproduced by the stereo section of your 2.1 amplifier, to which you should connect small, full range speaker drivers which have a good mid to high frequency response.
Something like this, which is available with an impedance of 4 or 8 ohms to match that of your Yamaha subwoofer: http://www.farnell.com/datasheets/2579669.pdf
The remainder of the audible range (250Hz and above) is reproduced by the stereo section of your 2.1 amplifier, to which you should connect small, full range speaker drivers which have a good mid to high frequency response.
Something like this, which is available with an impedance of 4 or 8 ohms to match that of your Yamaha subwoofer: http://www.farnell.com/datasheets/2579669.pdf
Yeah 6 ohms. Just to complicate things further 🙂
Im now thinking of actually buying selected woofers for the project now. 🙂 hahaha
Im now thinking of actually buying selected woofers for the project now. 🙂 hahaha
Out of interest, kerv, is this yout Arylic 2.1 amp board?
2.1 Amplifier with 100W+50W *2 for DIY Audio-Arylic.com
– arylic
2.1 Amplifier with 100W+50W *2 for DIY Audio-Arylic.com
– arylic
@Galu.
Yes i bought it about 2 months back thinking of doing this project.
Everyone thinks they can walk into audio, hammer a few pieces of wood and have a good sounding speaker. Well, i fall under the category of these people hahaha.. 1 week later and i am truely humbled.
Yes i bought it about 2 months back thinking of doing this project.
Everyone thinks they can walk into audio, hammer a few pieces of wood and have a good sounding speaker. Well, i fall under the category of these people hahaha.. 1 week later and i am truely humbled.
I realise that, kerv, I simply use the term satellites to describe the stereo pair of speakers as distinct from the subwoofer.
P.S. For some reason, your recent posts have been delayed or so close to mine that I missed them! I'll have to piece the conversation together in the correct order before I contribute further!
Last edited: