Bedroom music Need to build small speakers

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I need to use what I have and they need to be small.

Aussie query regarding the Jaycar CW-2315.

I hate to waste a Vifa M-22 in a too small closed box and I have a pair of the polycones sitting on a shelf, the P-13s need to be used and I will match them with the D-27 so the XO is no problem there, I just need a little extra bass and power handling and help with a 2.5 way.

Assuming I put the little 6inch in a 15liter sealed box 250mm wide and use a single inductor where is the best place to add the baffle step? P-13 rolls off at 200 in a small sealed box of 4litres ( has to be sealed- we have no room to spare and the finished box needs to fit the existing wall mounted stands ) Baffle step starts at ~400hz I assume and the little woofer has nothing to speak of below 50Hz
 
Hi Moondog,
If that's the CW-2135, even in 15 L I'd still vent them, tuned to ~50Hz - this will give a slight hump at the low end, but get you down to 50Hz. Closed, they'll roll off at ~ 100Hz.
I can dig out an impedance curve if you need it. The cw-2135's won't handle lots of power down low, but are good to medium - high levels.
If your P13s roll off at 200, that's where I'd size the inductor for. (or just try the biggest ones you've got on hand !)
cheers,
Pete McK
 
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Happy new Year Pete
Yes my poor reading and typing, they are the CW2135.
Unfortunately I have to use a sealed box because of the position of the wall mounted brackets ( which were placed for the pair of Sansui book-shelfs ) I do have several discrete sub boxes to fill in the bottom end if we feel the need.

I have still not ever built a series XO and thought this was the ideal opportunity as these little speakers will never ever have to play at party levels and I can give the midrange priority
 
diyAudio Member
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I just modelled both sealed and ported in small boxes i like the shape of the roll-off better with the sealed box, this is a very small bedroom.

i could get the overall size of the box down if I had a tweeter here that would come down to meet the P-13, unfortunately the D26NC needs at least a second order XO quite a bit higher than 2700 so i don't think it is suitable for a series XO.

Unless some-one has a cross-over already developed using this combination that is
 
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i have been doing some work on the XO using information from AndyGs site ( Thanx Andy ) and David Weems book.

Without modelling I know that what I have is just a starting point but I would appreciate any comments, "Speakerbug" have a good range of aircore coils and if I need a certain value they do not have ( 0.57mH ) I have assumed that going to the next closest standard value but with the lowest DCR is better 0.56mh being less than 2% different but half the DCR.

Do I understand correctly that with series XOs the cap in not directly in the signal path and quality of the cap is therefore of less significance?? and I can use the cheaper Jantzen Audio Crosscap and save some real money??

Second question now, how low can I cross a D27-45-06 using a first order series?? I have chosen 2700Hz as a starting point which is quite a bit lower than the little 2-way reference project using the same drivers.

Should I also use Vifas Resonance trap filter as part of the actual tweeter or just not use anything


P-13 will of course use a Zobel, ~15uF + 8R

I may also ( will most probably ) need an additional conjugate circuit to counter the woofers 12dB peak in response centered @ 2100Hz
 
diyAudio Member
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I could live with these "AS IS" just adding a little depth to a P-13 makes quite a difference even if it is a cheap woofer

This is just a quick baffle test to check my dimensions.
5.6mH on the woofer 3.3uF on the tweeter and some ploy and felt padding, I just love cardboard.

The 2YO just loves to help, the sharper and more dangerous the tools the more she likes to get involved
 

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diyAudio Member
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SWMBO now wants to hear the mid tweeter combination using the M-22 woofer rolled off at the same frequency, even tho she thinks the boxes may be too big, she can hear the peak in the little Response woofer better than I can. Therefore I am making some quick test boxes out of cardboard, they would be finished except I have run out of quick-set PVA
 

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Saw this topic when it started and I thought to myself: why does a bedroom system need to be put in this 'multi-way' forum instead of much simpler and smaller 'fullranger' type...?

Now this 3-way is coming up.

You must have a very big bed room. And look at those (lethal) huge magnets! I bet it'll be very good at being used as a wakeup call :D :D
 
Yeah, I just made a bedroom speaker system from 5 1/4" 15 watt full range car speakers. I made .5 cubic foot ported cabs hooked up to a 20 watt chip amp. Sounds really good in my 10' x 12' bedroom. However, it does not sound good at all in my family room - total rubbish.

Maybe Moondog does have a really big bedroom or he likes his music really loud.

Don
 
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Well we think it is medium size, our priority is clarity of the midrange, you just can't do that with a 2-way using cheap drivers, and Cecile gave me the P-13s as a birthday pressie 4 years ago, so they are the obvious choice.

They need to be physically small boxes for the reasons given in the first post and loud enough so we don't disturb her daughter sleeping 2 rooms away ( if you take my meaning)
 
diyAudio Member
Joined 2007
Yeah, I just made a bedroom speaker system from 5 1/4" 15 watt full range car speakers. I made .5 cubic foot ported cabs hooked up to a 20 watt chip amp. Sounds really good in my 10' x 12' bedroom. However, it does not sound good at all in my family room - total rubbish.

Maybe Moondog does have a really big bedroom or he likes his music really loud.

Don[/QUOTE
We consider our private space is entitled to the same quality of reproduction as the public space in our house, only have a small amplifier here tho, not the 800 watts Tri-amped monster in the lounge room, and 35 liters is small; tiny in fact when you consider she puts up with huge subs in the main system
 
im making my own slightly different version of this for my bedroom, about 14' square so not huge, but i reckon itll be loud enough to drown out the OH :D

Audax Mini-Monitors - Enclosure Design

now i doubt you can find the drivers anymore, the link was more for the general idea of my bedroom system plans...personally id use the p13's(?) in something like this, and hide a sub somewhere if really needed.....
 
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diyAudio Member
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Well after padding the tweeter and then using a series XO, SWMBO prefers the openness of the single cap on the tweeter and no padding resistor.
This has a lot to do with the .5 woofer, I think it is adding a dB to the mids, even if it is rolled off at 230Hz or thereabouts.
it is a combination that is easy to listen to, even if it won't rattle the windows.
Tomorrow I'll swap out the tweeter and let her listen to the D26, but crossed a little higher i think
 
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Query for those who built the 2-way reference project; did any-one experiment with a second order series on the tweeter??

I have been playing with the first order series XO and it is fine and sweet until i crank up the volume, tweeter seems ti distort a little at high but reasonable levels, and I was thinking that it may need a little less bass coming through.
other option is to buy some more parts and use the AR series XO, which i have not tried yet. Still to play around with a standard second order XO at around 2500Hz - 3k
 
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OMG I can't believe I am only just getting back to building these. Still using the P-13 and the D-27 but changed the woofer to the big Vifa P-25 so while I am working on new box dimensions ( which is partly why I went to using a low Q driver to get a smaller box but also it is much smoother at the top end so will work much better with a first order) but I have a problem.
Modeling the P-13 in a small sealed box ( 3 to 5 liters) and using a 8.2mH coil (rolling off above 110Hz) on the woofer while it sounded good on the test baffle it doesn't model that well
Sometimes the more I work on a design the more confused I get and I think I may have lost the thread where these design questions had already been asked and partially answered
 
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