| Ahmad_tbp |
hi
i wanna build a sub for my bass guitar ..
i donno too much bout the construction of sub-woofers case... :( ..
i just design this like FBT sub - woofers for my 12 " sony xs-l121p5 car subwoofer... can any body plzz look at my desgin & tell me how is it ? ..
is dimensions good ? ... any idea ? .. how is the iner construction ?
i ll be grateful for any idea ...
and another question ...
i wanna put my amp into this ..
i donno which arrangment is good ? .. i mean :
input ===> subwoofers filters & eq ===> subsonic filter ===> preamp ===> power amp ===> delay & short circuit protction ===> out ...
or :
input ===> preamp ===> subwoofers filters & eq ===> subsonic filter ===> power amp ===> delay & short circuit protction ===> out ...
is it good ? .. any idea plzzzzz ?
any good idea ? any good schematic or pcb layout for subwoofer filter & eq , or preamp ? ( i wanna use ESP p68 as my power amp ) |
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| quasi |
Hi Ahmad_tbp;
I could be wrong here so new information would be appreciated from anyone...
but...
A subwoofer speaker designed for car or home use would be very unsuitable for a bass guitar speaker. The efficiency and ruggedness of these would simply not cut it, particularly for stage work.
You need to look for extended low frequency PA (public address / musical instrument) drivers for your application. These will give you the efficiency and toughness required. Manufacturers such as JBL, RCF, Peavey etc come to mind, but be warned these units won't be cheap. See if you can find a well cared for second hand bass-box in the musicians trading columns.
Cheers :drink: |
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| DonoMan |
| Eminence will work too |
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| Ahmad_tbp |
it seems i should forget bout it :( ...
as i said befor in my posts .. a bass amp is too expensive in here .. tooooo expensive :( ... after years i could nt buy a second hand amp yet ! ,, i couldn t find !!!
so what do u think ? .. i have to build this amp ?? .. which subwoofer u offer ? .. somethin that i can find in here ? ... there s lot s of car subwoofers here ,, clarion , jbl , anythin :( .. they r not suitable ? ...
and are the power amp & other sections good ?
is the case good & suitable ?
& thnx DonoMan but i cant buy anythin from net :( ...
plz help me .. :( |
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| DonoMan |
| car subs will work somewhat but they are FAR from optimal |
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| quasi |
Hey Ahmad_tbp,
Yes JBL make car subs too but these are nothing like what is required in a bass guitar rig.
Unfortunately good bass boxes for bass guitar are physically large and usually have one (or two) 15" or even 18" PA / musical instrument speakers.
I remember seeing some RCF's that would do the job and they seem to be good value for money.
The power amp would be a good project to do and if you use second hand parts (as I did with my amp project) you could build it for very little.
Then you could buy or build the pre-amp section (could be quite complex) and work on effects units later.
Good Luck |
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| Ahmad_tbp |
thnx a lot man :( .. still havin trouble findin a good speaker here ...
:-< ...
i really don know what to do :-< ... :bawling: |
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| Ahmad_tbp |
| wowwww ,, i saw the rcf :bawling: .. i never can find somethin like that here ... |
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| DonoMan |
| if you really need to use car subs, then I guess your only option for volume is to do something like quad 12"s or build a couple of horns |
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| jcx |
| is this about SS Amplifiers? or sub construction? |
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| Ahmad_tbp |
lol, , what s extactly a horn doin ? :P ...
but i never seen a horn in here :P .. it s bettter to froget it & earn money for a practice bass amp .. :P |
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| Ahmad_tbp |
hi jcx
i m tryin to build a sub for my bass guitar :( |
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| quasi |
A quad box or maybe 2 x 15" subs could work because you would gain some efficiency by using extra speakers.
Most sub woofers that I have seen have efficiencies of 88dB or so (1w @1 mtr) compared tp PA drivers of around 94dB+.
So if you buy the most powerful sub woofers you can afford and then deliver only about half their rated power you should be ok.
You could build a quad box with 4 x "100w" 12 inch sub-woofers (check the real power rating) and end up with a 200 watt RMS 4 ohm box with an efficiency of around 92dB+
This would even cost less than one JBL.
The reason the numbers for the power rationgs don't add up is because I don't trust what's written on the box and I divide the power specification by 2. Also consider that a bass guitar note that isn't damped is basically a sine wave and this is very tough on speakers.
But if this is a practice amp with some light stage work then go for it!
Cheers: :drink: |
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| simon5 |
Your design is a dual bandpass subwoofer, a bit complicated for a first try, if it's designed by Sony to go with this subwoofer it's ok, but if you want to change the dimensions or something, it will probably sound very bad.
I suggest you to go less complicated for the first time, especially if you don't know the T/S parameters on the woofers you are going to use.
Go for a big sealed box, bigger = louder, and use several drivers if you can, like if you find a good deal on two or four 12" drivers of the same brand, same model, go for it.
You can make something not that bad, don't worry.
If the bass notes are not loud enough, you could tune the box with a long ABS pipe, but doing this is harder if you don't know the parameters at first, we would need to know the internal size of the box too.
For the component chain, I would go with this:
imput --> subsonic filter --> crossovers and eq ---> preamp --> power amp --> delay and short circuit protection ---> output |
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| DonoMan |
No. Bigger does not mean louder. It means low-end extension.
And I still think a horn is best. |
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| simon5 |
Well louder in the bass department... I always say that because unless you're going for SPL competitions, there's no need to have small boxes with high Q and one note bass...
Yes a horn would be the best, a little bit hard to design correctly... |
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| quasi |
A correctly built horn loaded box could be too big physically as a Bass rig you want to cart around.
The quad box or dual 15" rig in a sealed or ported box would be the way to go. It would be easy to port whatever box Ahmad_tbp ended up with for a good and deep sound. Remember we are not talking about hi-fi here so issues with port chuffing will not be a problem (no-one will hear it on stage).
I built 2 quad boxes a few years ago with the primary design consideration being able to fit through the back door of my car. I then ported the box using bass box parameters. How does it sound? wicked !
Everyone here is genuinly tring to help you Ahmad_tbp. Ultimately though try not to get carried away and the Sony design is getting carried away.
Go have a good look at what other base players are using and then build a similar box. Stuff it with your sub-woofers wire them up and then tune the box to get the correct bass extension. I and others here will show you how to do that (it is very easy).
Good luck :drink: |
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| Ahmad_tbp |
hi quasi,simon5,DonoMan.. thank u so much for help me ,, thank u so much ,,,
so u think it s better if i tryin to build a seald 4*12" or 2*15" box .. huh ? ...
i just looked at ampeg s a 4*12" & 2*15" cabinets ...
http://www.ampeg.com/products.htm?product=94&catid=11
http://www.ampeg.com/products.htm?product=31&catid=11
... what bout their dimensions ? .. are they good for me ? ..
i really donno what to do :( .. unfortanately i donno if i can buy 4* 12" good sub .. lol it s so funny !!! i donn have enough money to buy a bass amp , i don have money to build one ! & i want to have one ! .. lol
& what do u think if i just buy another sony p5 sub and build a duel 12" cabinet ? :P ...
& one thing else . that design is mine i really donno anythin bout what is T/S parameters ... i never see an inner subwoofer construction ... i just saw a fbt 12"dimensions .. & design a box like that , & think what is the inner construction can be ... & i think they may build it as i designed .,, so i draw it ! :P ... and now i found out i designed a dual bandpass subwoofer !!! lol
thnak u so much so much for help ,, i m so gratefull ..
i ll tryin to buy another sony sub :P . i really cant build a quad cabinet :P .. it s tooo expensive for me :( ........
:dunno: |
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| Ahmad_tbp |
hi
for test ( lol just for test the sound !) .. i ll tryin to build a small cabinet for my subwoofer this weekend .. & see how is the sound :( .. i ll inform u .. :( |
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| quasi |
Well yes you could buy another Sony Sub if money is the problem and run the 2 subwoofers. I dont' know anything about this unit but if it is a 4 ohm unit then you should run them in series. This will give you an 8 ohm impedance and while it wont be as loud as if you ran them in parallel (2 ohms) they will last longer because they will only be given half the power (remember sub-woofers aren't really designed for bass guitar.
Build a box something like the picture and build it as large as you are happy to carry around (it will be very heavy), just make it strong and use composite wood (particleboard or MDF 18mm+ thick). Once you have built the box you can either leave it sealed (safer and smoother bottom end response) or you can port it to give more efficiency (louder) at the bottom end.
If you can find the T/S parameters it could help you to build the right box, but don't worry too much because the box can still be "tuned".
I have built things before on a budget and you will be surprised at what can be achieved and how good it will sound.
Cheers |
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| quasi |
Sorry Ahmad_tbp
I was typing when you sent the last message. Good luck with the small box. Remember bigger is better (up to a point that is).
Cheers |
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| Ahmad_tbp |
hi quasi .. i donno how should i thank u ...
u help me too much man ;) .. thnx a lot ;) ...
sorry i have another question ,, it s beacuse of my english :P ..
i cant understand what do u mean :P .. what is "port" mean here ? | quote: | | ...or you can port it to give more efficiency (louder) at the bottom end.... |
i saw loudspeakers cabinets ( specialy subwoofers ) have a hole in them ... i donno what is it doin .. & i donno if u mean that by "port" ... is it the port u said ? :P ..
or not ,, what does that hole doin ? .. & how size should it be for my 2*12" subs cabinet ? .. :P
i ll send my design for 2*12" cabinet soon ;) ... & i ll build it w a thick mdf ;) ,,,
i really reaaalllyyy donnno know how should i thank u man ...
Cheers quasi ;) |
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| Ahmad_tbp |
i desgined too diffrent cabinet ...both are 18"*30"*18" ...
first one w one (or two) 4" hole & a 12"pipe !!! lol .. i just draw it cuz i saw this hole in most cabinets :P .. i have no idea bout this hole & pipe dimensions .. or what does it doin :P ...
the second draw , is a same cabinet but i divisioned the inner space by a 12" wall .. & put a 26"*2" hole at the bottom of the cabinet ... ( just like some cabinets i saw ) lol .. as i told i have no idea bout this hole too .. !!!!!!! lol
i just put these there as i saw in some cobinets ... any idea ?
is this box enough ? or i need a bigger one ? ...
and is this hole is nessecary ? or better if i make front panel seald ?
or if this holes are good which design is better ? . the cabinet w one(or two) hole in it or the cabinet as my second design ? ..
and plzz with which dimensions is good for them ? :P
thank u so much ...
( i m busy with my test box :) ) |
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| simon5 |
First, you should try a box with no hole. If you think the low frequencies are not loud enough, then you can make a hole. In that hole, you put a pipe. Longer is the pipe, lower the box will be tuned.
Remember to seal well your box, no air should come out of anywhere except air moved by the speakers. If you put a pipe in it, seal it tightly in the hole, the air should be only coming from inside the pipe.
If you go with the pipe, try a 3 inch diameter pipe first. If the pipe is making too much air noise, get a 4 inch diameter pipe. Remember that if you go with a larger diameter, you need to make it longer to tune at the same frequency. |
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| Ahmad_tbp |
hi simon5 | quote: | | First, you should try a box with no hole. If you think the low frequencies are not loud enough, then you can make a hole. In that hole, you put a pipe. Longer is the pipe, lower the box will be tuned. |
so u think its better if i build a sealed box first ..
i wanna order this box to a carpenter , i dont want to build it my self ... so it s maybe better if i order it w a 4"hole and ( or may be two holes ,, what do u think ? :( ) and for the first try seal the hole ( or holes ! ) lol ,, and then if i see the freq is not good open the holes ,,, do u think it s may be better ? ...
and what do u think ? one hole is enough or i should design the box w 2 holes ?
i draw another cabinet ,,, plzz take a look at it ...
it s so much bigger ... thnx a lot |
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| simon5 |
Yes you could order it with a 4" hole and seal it, then test the box, then put a pipe into it and test it again.
I suggest only one hole since these Sony subwoofer drivers are not moving that much air. Two holes need pipes alot longer to tune it at the same frequency.
The bigger your cab can be, the best it will be with a bass guitar. But it's harder to move hehe!
You could start with a 14 inches long port, then cut it inches by inches to see where you like the sound.
14 inches would tune this box around 20-25 Hz, then you can choose the tuning between 20-25 Hz up to 45-50 Hz with no pipe, only a hole. To tune around 30-35 Hz, you need a 6 inch long pipe, and so on.
If you knew the T/S parameters or know someone would could give them to you, it would be way easier for us to help you! ;) |
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| Ahmad_tbp |
hi simon5 ;) ...
i found this things :P ... it s in another language i donno what does it means :P :
T/S:
Impedance (Ohms): 4
D (mm): 250
D (inch): 9.8
Rdc (Ohms): 3.2
Fs (Hz): 26.4
Qts: 0.42
Qes: 0.44
Qms: 5.86
Vas (Lit.) : 55.5
Vas (ft_): 1.96
Mms (g) : 219.0
Lvc (mH) : 1.2
Xmax (mm) : 7.5
Xmax (inch) : 0.3
BL (Tm) : 16.1
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Impedance (Ohms) - znamionowy opor glosnika
D (mm) - srednica w jednostce metrycznej
D (inch) - to samo, tyle ze w calach
Rdc (Ohms) - impedancja cewki
Fs (Hz) - czestotliwosc rezonansowa glosnika (punkt najwyzszej impedancji na wykresie zaleznosci impedancji od czestotliwosci)
Qts - dobroc calkowita
Qes - dobroc elektryczna
Qms - dobroc mechaniczna
Vas (Lit.) - objetosc ekwiwalentna w litrach
Vas (ft_) - to samo, ale w stopach szesciennych
Mms (g) - masa ukladu drgajacego (membrana, cewka, zawieszenia chyba obydwa(?) )
Lvc (mH) - indukcyjnosc cewki
Xmax (mm) - maksymalne wychylenie membrany z pozycji rownowagi, po przekroczeniu ktorego zaczna siê znieksztalcenia w dzwieku
Xmax (inch) - to samo - w calach
BL (Tm) - sila napedu magnetycznego
.....................................................
Description:
12" Polypropylene Cone
1200W max input power (350W RMS)
Unique cone design offers superior rigidity
Gold-plated Binding Posts
Small sealed/ported enclosure optimized
4 Ohm Voice Coil
Specification --
Sensitivity -- 89 dB/W/m
Frequency Response -- 18 - 2,000 Hz
Mounting Dimensions --
Diameter -- 277 mm (11")
Depth -- 161 mm (6-3/8")
Weight -- Approx. 5.7 kg (12 lb 10 oz) per speaker
Gold-plated binding posts -- A solid, secure, simple and capable method of transferring serious current to speakers with protection against corrosion for lower resistance.
Polypropylene cone -- A plastic based material used primarily for speaker cones due to its resistance against harsh environmental conditions, rigidity, and damping.
4-layer edge-wound voice coil -- Start with an aluminum former and wind four layers of copper wire that's flat, rather than round. This allows the wire to pack together in a smaller space than would otherwise be needed.
Dual "Triple-layer" damper -- Three layers of high strength damper material make up each of the two spiders, ensuring virtually perfect linear travel of the voice coil. The lead wires are embedded in the top spider, preventing entanglement and extending the voice coil's throw.
Pentagonal Cone -- Improves cone rigidity for lower distortion, and reduction of standing waves on the cone itself, for cleaner sound and better transient response |
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| simon5 |
These are exactly what we are looking for. The T/S parameters.
These are the T/S parameters of your 12 " sony xs-l121p5 car subwoofer ???
If yes, then we will be able to help you design a good vented box with a pipe.
Edit: Just checked, you found out the parameters, I'll check how it's looking in WinISD... |
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| simon5 |
It's looking quite good, I tried a 4 cu.ft internal net volume with a 12" long 4" diameter pipe.
The maximum power you can put into your box for both woofers is 325W RMS, so you'll need a 325W RMS into 8 ohms or a 325W RMS into 2 ohms amplifier.
112 dB on the Low B string and 113 dB on the low E string, very flat frequency response curve. Maximum SPL is 114 dB at higher frequencies.
If your carpenter use 3/4" MDF or 3/4" plywood and he use some bracing in the box, your bass cab will be quite nice for a budget solution, probably beating some commercial bass cabs. |
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| Ahmad_tbp |
WWWWWWWWWWWWWWOOOOOOOOOOOOOOOOOWWWWWWWWWWWWWWWWWWWWWWWWWWWWWW!!!!!!!!!!!man
thank u so much mannnn :)
how should i thank u alllll ???
my test cobinet is near to be finished ... :)
i ll inform u :) ... |
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| Ahmad_tbp |
hi simon5 again :P ...| quote: | | ...I tried a 4 cu.ft internal net volume with a 12" long 4" diameter pipe |
what is a 4cu.ft internal net volume ? :P :cannotbe:
...
so u think if i build the 3rd design and use a 4" * 12" pipe it s good yeah ? ... |
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| simon5 |
I mean 4 cubic feet internal net volume.
Internal measurements of the box then you remove the volume taken by the two woofers, by the bracing and by the port.
Yes I think if you build the 3rd design, it will be ok. |
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| Ahmad_tbp |
hi simon5 :) ;) ...
i exactly understand whad did u mean :) ..
thnak u so muchhhh :) ...
............
i ll test my box in bout few hours :( .. i ll inform u :( ... |
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| Ahmad_tbp |
hi :(
i built a 18*14*11" box for my sub , for testin
w a 2" * 1 " long pipe :( .... the sound is realllly bad :( ..
it has somethin veryyyy bad like reverb , reflection ,, somethin like that :( ...
i donno why ? ... is it may cuz of my amp ? :( ... |
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| simon5 |
Your pipe is too short, the box is tuned way too high. Small box need longer pipe.
Try to fill the pipe very tight with a tshirt, socks, polyfill or something and check if the sound is better.
If not, maybe your box is not strong enough, step on your box or put heavy things on the box, then hold the sides with your hands and see if the sound changes.
Good luck |
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| quasi |
It seems that Simon5 has been helping you quite well. I am sorry I went quiet for a while but I was working on other stuff.
As Simon suggested your port is too short and I also think your box is too small even for only one woofer. Simon's idea of stuffing the box is a good one. This will help to stop echoes inside the box and also make the woofer think it's in a bigger box.
I ran the information you provided through WinISD as Simon did and came up with this.
A box of 63.4 litres (sorry I cant get my head around cubic feet) and a -3db point of around 25Hz. Pretty good.
If you plan to use two woofers then you will need to double the size of the box.
Cheers :drink: |
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| quasi |
If you want your speaker to go lower (I don't know how many Hz the top string of a bass guitar is), then you need a bigger box.
I tried a big box in WinISD and got this. This is only for one speaker. Lower bass usually means a bigger box.
Cheers |
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| quasi |
I've just read that the top string on a bass guitar is 41 Hz.
So you don't need too big a box. I have guessed the internal volume of your box so here it is in WinISD. Looks good, get the ports right and it should be a winner.
Cheers |
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| Ahmad_tbp |
hi all ,,, hi simon5 , hi quasi ;) ...
thnx a lot ...
i just came back from university ... i started testing subwoofer again w a very simple 25w tda7265 based amp & i use a sine wave generator program to make the signal ...
here is my result :P ..( in same volume )
20 hz : the sound is very very low , & i almost hear nothin :( , but when i turn the bass volum a bit higher the speaker is startin to shaking very bad ...
30 hz : still hear a very low sound
40 hz : the sound get a bit louder ... !
50 hz : louder again !
100 hz : the sound is LOUD !!!
150 hz : the sound get low
200 hz : lower again :( ...
300 hz : lower again :( ...
in 1000 hz the sound is very very very low , almost as the same i started the test in 20 hz ... ( and there s no diffrence if i turn the bass volume all the way up )
in 2000 hz i almost hear nothin :( ...
i donno ... :(
so u think it s cuz of my box ,, yeah ? ..
i ll completly seal the box & i ll test it again simon5 & i ll inform u ... |
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| Ahmad_tbp |
hi quasi :) .. & welcome back ;) & thnx a lot for testing ...
i have a five string bass , & my lower string has a 31 hz freq ...
so u think i should build a biger box ???? :( ...
or the 24"*24"18 cubic box is enough & good ? :)
simon said that the 24"24"18" box w a 4"12" pipe is ok for me .. i donno anythin bout the winisd .. so what do u think simon & quasi .. :( what should i do ? |
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| quasi |
According to WinISD for a flat response down to 30 Hz the following applies.
A ported box with an internal volume of 65 ltrs
A vent that has an internal diameter of 82 mm and is 268mm long.
You will need to experiment a little with the port to get it just right especially if you can't get pipe exactly 82mm wide.
Cheers |
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| Ahmad_tbp |
hi quasi ...
so should i build a 24"*24"*18" box ??? or i should double the size ? :( ....
and i should use a 3.5" * 11.5 " pipe .. yeha ???
i m gettin little confused :P ... |
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| quasi |
What do you normally use over there? Feet & Inches or millimetres?
How thick is the wood you are using?
Cheers |
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| Ahmad_tbp |
hi quaaaaaasssiiiii :)
we use millimetres :) ...
& i wanna use a 18 mm mdf ( or 20 mm if i find )
;) |
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| Ahmad_tbp |
hi guyz again .. & onething else :P ...
what if i add a 12" woofer w built in tweeter in this box w seprated amp for mid and high freq ???
plzzz help me ,
at first i decided two build two cabinets ,, one for subwoofer & one for higher freq ...
but now it ll become tooooooo big ...
& what bout if i build a bigger box and put them together ? ...( a box around 32"*32"*20" )
will u plzzzzzzzzzzz help me :( ... |
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| Ahmad_tbp |
hi again again & again :P
i just sent a post for help on constructin a psu without a transformer on solid state section ...
u guys have any idea ? :)| quote: | | how can i built a 90v 3-5a heavy duty PSU without using a transformer for my amp ? ( just like computer s power supply ) |
..... :D it seemz my questions will never end till every body run away from me !!!! lol ...... |
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| quasi |
Ok...lets see;
If you want to put all that stuff in then build a very big box.
The picture shows what your response will look like and gives enough detail to build it.
Never built a power supply without a transformer. This provides the isolation needed to keep you alive if something goes wrong
Good Luck |
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| Ahmad_tbp |
hi all again ...
how is this ???
i designed it , w the parameters that quasi give me ...
a 44"(1097mm) * 24 "(699mm) * 18"(434mm) box
w a 3" diameter & 6 " lenght pipe |
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| simon5 |
Hi, sorry I was away for the weekend.
Yes, your test box is probably too small so the 100 Hz band is boosted way too much.
Your idea to add a 12" woofer with integrated tweeter is not a bad idea, but you'll need to add a passive crossover network.
I'm sure that two woofers in your 24" x 24" x 18" box will sound great with a 4" diameter pipe. I would use a 12" pipe if you plan to play more inside, and 8" pipe if you plan to play more outside.
If you still want to add that 12" woofer, I would add it on the top of the box but keep it separated from the rest of the box with a layer of MDF. I would also angle it maybe 15-30 degrees to point at the listener.
Here is the simulated design of your box (with 8" pipe in red and 12" pipe in yellow) with bracing inside (I strongly recommend you to add bracing in your box). |
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| simon5 |
Here is to show you the difference between your test box with a 2" diameter pipe of 1" long versus the box you want to build.
I used your 25W opamp versus 300W for the box you want to build (150W per subwoofer) and I used the outside configuration so 8" long pipe.
You can see why the sound is so bad and why it's only loud around 100 Hz.
Remember that the frequency response over 300 Hz is not accurate, it's just to give you a general idea why your test box is not perfect. |
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| simon5 |
If you seal your pipe in your test box, like me and quasi recommended, you'll be able to do better testing with your subwoofer.
Here's the response, it'll be much better. Look by yourself. |
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| Ahmad_tbp |
hi simon5 , & well come back ;)
as u see , i think it s may be better if i use a woofer w internal tweeter w this cabinet ...quasi told me to build a 44"*24"*18"
box w a 3" diameter pipe & 6" lenght ... so u think i should use a 4"diameter w 12"-8" lenght w this 44*24*18" box ????
and u think i should seprate the woofer & sub woofers sections ... so i think if i do that we should calculate everything again ... yeah ?
here is a desgin again ... plz help me w sizes ...
and one thing else .. should i add a pipe for woofer section ??? or leave it sealed ??? |
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| Ahmad_tbp |
hi again :P| quote: | | but you'll need to add a passive crossover network. |
have any idea , schematic , pcb for that plzzzzzzzzzzzzzzzzz ??? :(| quote: | | I strongly recommend you to add bracing in your box |
:P .. may be my question seems silly , but it s cuz of my english :P ...
what is bracing ??? .. u mean i should build my box so strong ??? |
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| Ahmad_tbp |
hi again again again !
lol .. i tried to seal the pipe in my test box :) .. and WOWWWW the sound is great if i want to compare it w the first try :)
thank u so much guys ;) ...
but in 60 - 80 hz my box is shakin vey much , i think it s cuz of the box s not strong enough :)
i wont believe the sound changed that too much ...wow tnx a lot all ;) i m gettin hopeful :)
help me build my main box :) |
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| simon5 |
Hi, yes you should keep the woofer with a tweeter part sealed. No pipe for this part.
I would keep the 4" diameter by 12" long pipe for the main part if you play more outside or 8" long if you play more inside.
You could build the main part first and if you're not satisfied, you could add the woofer + tweeter part. You can also build them both at once. I can try to help you with the passive crossover, but I don't have any frequency response curves of the woofers you are using so I don't know where we should make the crossover frequency.
Bracing is MDF with holes that you put inside the box to make it stronger. With holes, the air can move in the box.
Here is an example for the angled front end with dimensions and an example of bracing. I'm not as good as you with drawing software hehe! |
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| Ahmad_tbp |
hi simon5 ... & thnx a lot ...
thank u for explainin bracin ;) .. i ll do as u say ;) ...
so i ll send u another design w the parameters u gave me ;) ... i don want to give an angel to the woofer/tweeter section , cuz if i want to use it on stage , it will be on top of the stage , and the listener are at the bottom of stage , so the angel should be down ( i donno if i can explain my mind good in english :P ) ...
and for crossover i just saw some second hand speaker i donno anythin bout the parameters of them , if i want buy a one i ll inform u ;) .. but totaly i wanna use sub woofers for 30hz to 500hz ( or maybe 1000hz .. i donno ,, what do u think ? . can the subs respond well in 1000hz ? ) and use the woofer/tweeter for above 500hz ,, ( till 10khz or 15khz ) ...
BUTTTT ....
there s a very big problem :-< ... the project maybe stop :-< ...
i couldn t find any transistors for amp ... i m still searchin for an amp ... all high power amps , use high power transistors , and i cant find them here ... :-< ... i donno what to do ... :bawling: i have to build this amp , but ,, it seems all the doors are closed to me :P
thnx all for help ... i donno if i can finish this project cuz of amps ... anyway thank u so much all , i learned too much from u men ;) ...
and special thnx to simon5 & quasi for helpin me a lot ... :( ...
i m so grateful to u , i donno how should i thank u ...
do u have any idea for amp ????
( where is quasi ? )
i ll send u my design ... |
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| simon5 |
Well lower the frequency is, better it is, but for your application, maybe it's better to cover most of the frequencies with your subwoofers, since a bass guitar is hard on drivers.
As you said, use a design with no angles then, it will still be great sounding, and stronger. You could use some polyfill lightly packed in the woofer + tweeter separate section. |
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| Ahmad_tbp |
hi simon5| quote: | | You could use some polyfill lightly packed in the woofer + tweeter separate section. |
what is that ? |
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| simon5 |
It's a material that when in a box, the woofer thinks the box is bigger than it really is. It's also lower the sound level a little bit but usually the sound quality is better when you use polyfill.
It's looking like that:
http://www.partsexpress.com/pe/psho...tnumber=260-330 |
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| Barton |
Not to butt into this thread, but....
I've been a working bass player for about 20 years. I had the bright idea to try the car subwoofer experiment when a local store had 10" IMPP (cheap Pioneer, I believe) subs on sale for $65/pair (US). The verdict: surprisingly good.
For what it's worth, here's what I discovered. First I tried them in a small sealed box. This worked okay unless I kicked up the bass (I was afraid a voice coil might go flying across the room). Better I think to tune the cabinet a little too high than too low--a well-thumped low string is mighty. That behind me and really wanting some low end thump, I built a fourth-order bandpass box (thanks WinISD) and the results have been amazing. Very solid to about 150 hz and surprisingly good power handling. The published power rating is 125 watts each. I have them wired in series and run 250 watts at them all night.
I like what I've ended up with. A "rumble box" to take the beating in the low frequencies, and a 2 X 12" to handle everything above 200 hz or so. One more thing: A compressor on the bass guitar is absolutely a necessity. These car speakers cannot handle the transients an uncompressed bass delivers.
So, it can be done. This is my introduction to this site. Hope I haven't broken protocol. Very good postings and good information here. |
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| Ahmad_tbp |
hi barton , welcome and thank u so much for postin ...
i m tryin to build a box w the help of simon5 & quasi ( i thank them too muxh ) and the parameters they give me ...& u think i need a compressor ???... i built one bout a year befor ... it was ross compressor , u can find the schematics and pcb layouts on www.tonepad.com ..
i donno if u try it or not ,,, but it don satisfy me , maybe cuz i expect it too much ... what is exatcly a compressor will doin here .. ???
the subs may have problem w bass frequancies but does the compressor change the freq for them ? so they can handle it better ??? ( sorry maybe my question seems silly :P but i confused )
do u have any idea for compressor & specialy limiter barton ???
any idea will be sooooooooooooooooo welcome ;) |
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| Ahmad_tbp |
| ( he he he it s my photo :D ) |
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| quasi |
Hey there are no butts here....
It's a good idea using the 4th order badpass for the extra low stuff Barton. It would need to be accurately built and very strong but I have run some 4th order and 6th order sims in WinISD for other speakers and have come up with some interesting concepts. It does depend on the quality of the woofer a fair bit, I guess any design does.
I did not think of a two way setup as you have. So if you're up to it Ahmad_tb you could run your sub in a 4th order box and then run another (different) speaker for the upper bass. This will provide more efficiency because you could tune each section seperately.
I'll run the sony woofer through WinISD as a 4th & 6th order and see what shows.
Cheers
PS. nice photo...you are a lot younger than me...:( |
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| Ahmad_tbp |
hi quasi :) ... welcome back ;)
| quote: | | It's a good idea using the 4th order badpass for the extra low stuff Barton |
what is the 4th order & 6th order ? :P :cannotbe: | quote: | | you could run your sub in a 4th order box and then run another (different) speaker for the upper bass |
i donno if i get u , but i wanna do that , build a box for woofer & subs ,,, and seprate them inside ... i sent a dsign for that , & ill send a new one ,,, and use the subs for extra low freqs & woofer/tweeter for higher freqs
wil u plz explain what do u mean a bit more ? :P .. ( sorry my english is very bad , i need to read ur mesages several times to understand what do u mean :P ) |
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| quasi |
Hi Ahmad_tbp,
The 4th order box described by Barton is a speaker box designed two work only in a narrow band (section) of sound. Inside this band the sound can be louder than a normal speaker box but outside this band the sound volume dies quickly.
Bartons idea is to have a normal box for all of his bass notes plus a 4th order box to boost the very low bass notes. I think it is a good idea but I think you should do this job in two parts.
Build a normal box first and then get this to sound as good and as loud as you can. Once you are happy with this then build the 4th order box. This way you can gain the confidence with the simple box first and understand how speaker boxes work before you build the more difficult box.
To help you understand what a 4th order box looks like and the way the sound output looks I have created one in WinISD. The sound response is the curved line. Do not build the box shown, it can be improved.
Cheers |
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| Ahmad_tbp |
wowww thnx a lot quasi :) ...
at sure i ll build it one day , when i become rich enough :P ...
( this 4th order box looks like what i designed for first time in this thread .. yeah ??? )
so man ,, what do u think bout a box w seprated sections for subs and woofer/tweeter ??? is there any problem ?
and any idea for amp ???? i still donno what to do w amp :-< ... |
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| quasi |
It's different because with the 4th order box the woofer is inside the box (you can't see it from the outside). All the sound comes from the port only.
When I'm rich enough I'll build one too.....oh well one day.
Cheers |
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| Ahmad_tbp |
i measured the notes freqs of my bass ( w a tuner program )
my lowest string has bout 31 hz and my highest last note has bout 330 hz ...
when i turn the treble volume all the way up on my instrument , the sound that came out from my speakers is too high and sharp , but the freq doesn t change ... why ?? .. why the freq doesn t change but the sound become too treble and sharp ??? :P ...
is it better if i tune my subs box to respond 31 to 500( 500 hz cuz the tune of notes will change in diffrent songs )
and woofer/tweeter section for above 500 hz ??? .. should i use crossover now ?? . any idea for crossover ??? ( i wanna use seprate amps for subs and woofer/tweeter ) |
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| Ahmad_tbp |
| well quasi ...i n my first design i wanted to sealed the rear panel too , but i dont show it in that pic , cuz i wanted to show the inner construct ... |
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| quasi |
| quote: | Originally posted by Ahmad_tbp
well quasi ...i n my first design i wanted to sealed the rear panel too , but i dont show it in that pic , cuz i wanted to show the inner construct ... |
Aah ok.
You could get a small 10" to 12" 150 watt PA speaker to take care of the 500hz and above plus a piezo horn tweeter for the rest. This speaker would not be very expensive (about the same as the subwoofer)
A 4th order box will not go to 500hz though so you will need something in between.
Cheers |
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| Ahmad_tbp |
| quote: | | A 4th order box will not go to 500hz though so you will need something in between |
am i goin to build a 4th order box ????
i have trouble findin transistor for sub amp .,,, not for woofer amp :bawling:
and i almost forgot somethin u said i m younger than u so should i call u Mr. Quasi ? :D |
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| Ahmad_tbp |
finallllllll drawinnnng :) ????????
w baracin !!! :)
any problem ?? any ideaaaa guys ??? |
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| simon5 |
Your final drawing is nice, but I would add two pieces of wood in it, just to be sure! :D
Two 9" x 24" braces, one between the rear panel and the center brace, the other between the center brace and the front panel, between the two woofers.
You need to leave a bit more wood between holes, to keep some strength, also don't place the bracing exactly in the center, put it off center, it's better to control box resonances. If there's the same distance between each panel and braces, then the box will resonate at that frequency. Since your box is not a perfect cube, it's less of a problem.
I'll show you an example here... you'll see that there's some bracing and that most braces are at a different distance from the other braces next to it. It's more important in this box, since it's a perfect cube.
Here you can consult the original plan to construct it to see the dimensions by yourself, it's the last design (EBS 142.5 liters) at the bottom of the PDF document:
http://www.adireaudio.com/Files/Ven...pplications.PDF |
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| Ahmad_tbp |
hi simon 5 ;)
i ll do somethin like that .. ;) .. thnx a lot ...
and thnx for explainin polyfill ... but i never find it here ;) |
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| Ahmad_tbp |
hi aaaaaaaallll ;)
i m busy w amp :) ... i think i find a way to build the leach super amp w mj15015/16 for my subs :D
any idea ???
do u have any idea , for protectin circuit , and sub filter and of course crosswover ... ? any good pcb or schematic ?
i m awaitin ur ideas ... ;)
( i just removed my photo !!! , i have no idea why i put that there .. do u know ? lol :P )
:smash: |
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| Barton |
Ahmad-- the compressor/limiter is just to keep the signal from being too peaky (very loud/very soft). Pro sound reinforcement speakers with a good quality high-powered amp can handle strong low frequency notes (think of a bass drum). Since I have neither--great speakers or a great amp--not using a limiter would lead to horrible sound at the least or blown up equipment at the least. To address your question, for what you're trying to do, any halfway-decent compressor/limited ought to work fine.
If I may take the thread on a tangent for a moment -- Simon or Quasi, any ideas how to handle ringing in a bandpass box. I've lined the rear chamber and left the front unlined as per the directions, but it seems like the front chamber rings... |
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| Ahmad_tbp |
hi burton
i have a compressor , but i cant find any pcb or schematic for limiter :( ...
any idea for limiter ???
( i m tryin to build amp :smash: ) |
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| quasi |
Hi Barton,
I would have thought that the front chamber i.e. the ported chamber in a 4th order box would have behaved similarly to a normal bass refelex box. These are normally lined quite heavily with sound deadener. If you've got an old woolly jumber stick that in there and see what it does. Try an leave the port entry clear.
Are the panels in the front chamber braced? The front panel could be vibrating so a wide panel to panel brace may help, but try the woolly jumper first.
Cheers |
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| Ahmad_tbp |
hi quasi , i ll bracin the front panel as simon said ... | quote: | | If you've got an old woolly jumber stick that in there and see what it does. Try an leave the port entry clear |
sorry . but what is wooly jumber ? ... i can t understand what do u mean :P ... |
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| quasi |
| quote: | Originally posted by Ahmad_tbp
hi aaaaaaaallll ;)
i m busy w amp :) ... i think i find a way to build the leach super amp w mj15015/16 for my subs :D
any idea ???
do u have any idea , for protectin circuit , and sub filter and of course crosswover ... ? any good pcb or schematic ?
i m awaitin ur ideas ... ;)
( i just removed my photo !!! , i have no idea why i put that there .. do u know ? lol :P )
:smash: |
I have a circuit for a DC detector to protect your speaker if your amp fails. I'll find it and post it to you.
As far as the other stuff goes, if this box and amp are for your bass guitar only then I would forget the sub filter and any fancy crossover. I believe that the sound of bass guitar should not be filtered because even though technically it only plays bass there are many harmonics that contribute to the sound. Why would you want to lose the clicks and snaps of great bass riffs? Invest in a simple compressor instead or make one (compressors are easy).
You must run a full range PA speaker as well as your subwoofer because the subwoofer will not go high enough. This also removes the need for a midrange. If you decided to run a horn tweeter as well then a simple series capacitor will be enough crossover or just use a piezo instead.
Cheers |
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| quasi |
Haaaaargh ...did I say Jumber? :xeye: I meant woolly jumper. Does it get cold in Iran ...if it does then you have a woolly jumper. It is something you wear to keep warm . LOL.
Cheers:) |
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| Ahmad_tbp |
hi ... yeah it s become cold , but not too much ..
i already have built a compressor bout 1 year ago ,,, but i donno how to build the limiter , i don have any schematic or anythin for it :( ...any idea ? |
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| simon5 |
You must be "VERY" careful with polyfill or any kind of sound deadener in a bandpass box. It will change the tuning, and the tuning of a bandpass box is very picky about effective chamber volume.
I recommend to add bracing on the front chamber, it's a large chamber or not? Tried to put heavy stuff on your subwoofer or pushing on the side to see if it's changing the sound?
Sometimes it can be a leg that's a bit too short or something ringing in the room also... good luck! |
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| Barton |
Thanks a ton Simon and Quasi. I'll try this stuff out tonight.
Ahmad -- you really don't want a limiter. Just use the compressor you built. One thing about compressors: the more you compress the signal the more low end you'll have. One of the experts could probably tell you why; I don't know. Be advised that you'll need to reduce the low end if you use much compression.
How's the project coming along? |
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| Barton |
| Simon & Quasi -- you two had it right. The general ringing was lack of bracing in the bottom. I ran a sweep from 20 to 100 hz and the box just lit up about 45hz--I thought it might do the out-of-level washing machine thing and just take off across the floor. Some bracing took care of that. I put carpet pad on two sides of the front chamber which got rid of some additional ringing. Thanks again. |
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| Barton |
| Simon: I had a question about the EBS enclosure pictured in your earlier posting. Are those cubbies (square areas with partitions having circular passthroughs) tuned resonance cavities or just a way of doing bracing? Excuse my ignorance, but I've never seen anything like that. |
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| Ahmad_tbp |
hi Barton
yes ,, they r some kind of bracin ...
and i still stoped in amp :( ..
i boughht some equipment for silk screen printin ,,, but i cant make them work :P ... |
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| Ahmad_tbp |
hi all
another design , w bracin ... ( a lot bracin !!! )
and maybe a bracin in woofer section ( i show it as wireframe ) ...
and with a left view to show the location of bracings ...
is it goooood ??? |
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| Ahmad_tbp |
hi Barton ...
so u think i don need a limiter .. ( thnx god ! lol ) |
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| Ahmad_tbp |
hi any body out there ? :( ...
if i use bracin inside the box , should i change the pipe size or diameter ? |
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| quasi |
| quote: | Originally posted by Ahmad_tbp
hi any body out there ? :( ...
if i use bracin inside the box , should i change the pipe size or diameter ? |
You could try to work out the volume of air the bracing takes and then adjust you box size to make up for it.
But don't worry too much. It will be easy to adjust the port.
Cheers |
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| simon5 |
| quote: | Originally posted by Barton
Simon: I had a question about the EBS enclosure pictured in your earlier posting. Are those cubbies (square areas with partitions having circular passthroughs) tuned resonance cavities or just a way of doing bracing? Excuse my ignorance, but I've never seen anything like that. |
It's just a way of doing bracing, I followed the plan shown on the link above the picture. It's the EBS enclosure plan made by Adire Audio.
The same piece of wood can touch 4 box walls to prevent flexing, very good bracing. |
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| simon5 |
| quote: | Originally posted by Ahmad_tbp
hi all
another design , w bracin ... ( a lot bracin !!! )
and maybe a bracin in woofer section ( i show it as wireframe ) ...
and with a left view to show the location of bracings ...
is it goooood ??? |
Yes, it's good, but I would use smaller holes on the big piece of wood in the center, so that the two braces behind have wood on each side, like in the picture I showed you. It will be stronger this way. I would also push the center piece a bit more in the center, it can be *almost* in the center like I said, just not exactly in the center. I'm a bit perfectionist you know, if you're already satisfied, I think it will sound right already...
You can add bracing in the woofer part if you want to, it can help. But in that part it's more important to use some kind of stuffing. Check around you to see what people use inside speakers for stuffing, stuff like polyfill.
When you are ready to build your box, you can tell us and we will help you calculate everything to remove volume taken by the port, speakers and bracing. Then, we can tell you the final port length. If you are good in mathematics, I guess you can calculate the internal volume easily... |
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| Ahmad_tbp |
hi all , thnx for help :) ..
i m goin to see some carpenter ;) .. and i ll inform u bout the inner volume .. thank u so much men ;) |
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| Ahmad_tbp |
project is still stop :( ...
i just think its maybe better if i tryin to earn money & buy better speakers .. what do u think ??? :( |
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| Ahmad_tbp |
anybody out there ??? :(
any idea for a 300w+ Public Address amp ???? :( |
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| simon5 |
| Well I guess that bass cabs are really expensive in your area and good speakers are really expensive too. I think your idea could be a good first try. I can't help you on the amplifier part... |
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| Ahmad_tbp |
| lol .. yeah , they r really expensive ... |
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| Ahmad_tbp |
hiiiii simon5 & quasi & others ... i m back again !!! ...
lol .. hope u help me again ...
i bought two RCF 12" full range speakers , and another sony sub ...
plzz help me design my cab again ,, im starting to buil the leach super amp for that .. any idea ???
how are the RCF speakers i bought ???
i coudn t find any info bout them on net the are rcf L12-31k ... |
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