I have a question about a subwoofer I am planning to build in a 350 liter cupboard space in the corner of my room (15 x 3.5 feet). The idea is to make a transmission line of 3 meter with a target of 30 Hz. I have four small 6 inch woofers (Sonic SLE 60/120), old and no specs, I only know they have a high QTS of about 0.7 and a Fs around 30 hz. The four small woofers together have a 400 cm2 total surface. Could this work? What are your thoughts...
Random/blind(no TS parameters) shot in the dark.
?taper it to 200cm2 from 400cm2 and Fb @ 25 hz or so (high qts and Fs of 30hz)?
flying blind without TS parameters is a bad idea, but here’s a bad guess 😝
?taper it to 200cm2 from 400cm2 and Fb @ 25 hz or so (high qts and Fs of 30hz)?
flying blind without TS parameters is a bad idea, but here’s a bad guess 😝
unfortunately there is no data and I can't find it on the internet.. these bass drivers were produced for a short time: Sonic SLE60/120 in Japan I think.. they have very light Styrofoam cones. long excursion and I estimate 85 dB sensitivity
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Falling back on my early days of having/needing only its Fs spec, then using a nomograph of the times that factors in some additional output impedance that makes it somewhat bigger than today's typical calculations (a good plan for a TL), then an ideal Av = Sd = 400 cm^2 vent requires a ~9.5 ft^3/269 L for 30 Hz, though it won't tune a TL to 30 Hz, so you'll have to use software to sim and/or ideally fine tune to actual Fs in room.
o.k. i have the possibility to tune the length of the line and tapering if needed. Everything will be screwed and not glued so easy to adjust panels ect. my main speakers (closed enclosure) go down to a usable 35 Hz so i want the transmissionline only around 20 - 35 Hz max. Above that my mains do very well. I am a little concerned about time delay between main and sub, i do not know if that could be disturbing the good impuls of my main speakers. thanks!
I decided to change the transmission line as part of my furniture, tv stand ect. mounted against the wall so it serves more purposes. It's a line of 244 cm (max. size of ply wood). I will first build it as raw housing and test it in position before i finish it. It will do only 20 - 40 Hz so i do not expect resonances. The bass drivers (16 cm / 100 cm2) will be facing down and not in sight, 40 cm from the floor. Any thoughts about this design?
would go low but i will loose 50%+ output form these already smal drivers considering 4 driver output plus TL output, isn't it
240 cm ~32hz
80 cm ~108 hz
48 cm ~ 180 hz
you sure you wanna listen to all that other noise ? the recent 4 driver folded pipe I did sounds like a ‘ box’
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Explain your self, why a open TL with 4 drivers would sound like a box? I will feed it with a subwoofer amp with a cutt of at 12 dB at 35 / 40 Hz so al higher frequency's will be not there...
He refers that you need to place the driver at the right offset distance in the TL, if is not optimal aligned you will have all kind of nasty harmonics above 100hz that in the real life sound "boxy" and "boomy" and that canot be fixed with DSP.
now i get it, thanks 😉 so, even if you feed the sub with low frequency's between 20 - 40 Hz, you will get these resonances? I will off set them, how far do i need to stay from the right? I will make the TL around 3.2 meters and have space to adjust. Could this work? (drawing)
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As every case is different, because of the drivers and cabinet dimensions, horn resp is your friend, you must tweak your ofsets inside of horn resp and watch the power output graph as you tweak .the less crap you have above 100 the better. At least not those horrible peaks.
See designs and responses from cabinets already designed. And the most important...
Actually builder and measured for freq response...
You can simulate all day ...all week...all month but until you make sawdust and measure what you made ,that is where the real fun begin.
Is better to have some me kind of sub than not sub at all 🙂
Some member wise words.
See designs and responses from cabinets already designed. And the most important...
Actually builder and measured for freq response...
You can simulate all day ...all week...all month but until you make sawdust and measure what you made ,that is where the real fun begin.
Is better to have some me kind of sub than not sub at all 🙂
Some member wise words.
i love this stuff!! A bit ‘deeper’ than bass reflex in the same volume enclosure(but that pesky pipe resonance needs to be ’fixed’ )
some people claim pipes sound better? I dunno.. but definitely interesting (you can give it the beans!!!) when you dont have that ‘undersized’ BR port noise ?
some people claim pipes sound better? I dunno.. but definitely interesting (you can give it the beans!!!) when you dont have that ‘undersized’ BR port noise ?
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…(ugly, raw unstuffed versions in horn response pic)
i built two if these (one is drivers @ start, the other is @ ~1/3 )
i built two if these (one is drivers @ start, the other is @ ~1/3 )
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Tang band w5 300 cm2—> 75 cm2 in ~180cm
these little turds:
https://www.parts-express.com/Tang-...per-Cone-Subwoofer-Speaker-264-917?quantity=1
these little turds:
https://www.parts-express.com/Tang-...per-Cone-Subwoofer-Speaker-264-917?quantity=1
