If you're talking about my modeling of your design, my model pretty much validates what you modeled. Are you now suggesting that you increase the taper ratio beyond the ~4:1 ratio in our modeling by using a 45-degree angle? If so, that would increase the taper ratio, which would make the line's effective length larger and lower its 1/4-wavelength resonant frequency, essentially no longer optimally tuned. With a larger taper ratio, then, the line's length would have to be decreased in order to restore its 1/4-wave resonance appropriately. Maybe I don't grasp what you're suggesting now?
Paul
Paul
Hi.45degree angle is just about construction of the box.Make box stiffer.Not about inside volume or ratio or acoustics.
We did it 520/120 surface ratio.For my TS parameters can you suggest a better box? Maybe deeper bass? What about if i make 640/64 ?
what ratio you make if you have these drivers?
We did it 520/120 surface ratio.For my TS parameters can you suggest a better box? Maybe deeper bass? What about if i make 640/64 ?
what ratio you make if you have these drivers?
I'm sorry but I still don't understand what you mean by the 45-degree angle. Regarding the line's taper ratio, changing it will not give deeper bass. In conjunction with the driver's T/S values, primarily fs and Qts, there will be one and only one optimum tuning frequency that provides an overall acceptable bass response shape. Once you've determined what that is, the bass reach, f3 for instance, will be determined by how much volume is in the line, more volume, lower f3, but you then have to keep an eye on the driver's excursion. The primary benefit of a larger taper ratio is that is also helps make the overall response smoother, but it also requires the line to be shorter as well as keeping your eye on the air velocity in the terminus. A 640/64 ratio might be fine as long as the (shorter) line's length in conjunction with that ratio creates the optimum tuning frequency.
Paul
Paul
Thanks, phivates, that makes sense. Now for umut1001, I modeled a line with a taper of 640 cm2/64 cm2 which required the line to be 127 cm long in order to achieve the same tuning frequency as with your original line. The driver's center is located 25 cm from the beginning of the line, and the first 86 cm of the line's length are filled with polyester fiber at a uniform density of 0.75 lb/ft3, requiring a total of 15-16 ounces (~500 grams) of fiber. I've attached the modeled anechoic system bass response.
Paul
Paul
Yes i meant this is about joints.Thank you
Oh i did not know the line should be shorter when area is bigger.I thought the longer line the deeper bass.
My tower speaker should be 20cm wide and 80cm tall and max 40cm deep.I think 640cm2 s1 is also not possible when i double check.
Maybe we can make another simulation.Or i will go with 520/120cm2 inside area.
And i could not find MK software.Is it a paid software? Is there any improvements over Hornresp.Sorry i am new to TL.I just want to make the good one as soon as possible.
Oh i did not know the line should be shorter when area is bigger.I thought the longer line the deeper bass.
My tower speaker should be 20cm wide and 80cm tall and max 40cm deep.I think 640cm2 s1 is also not possible when i double check.
Maybe we can make another simulation.Or i will go with 520/120cm2 inside area.
And i could not find MK software.Is it a paid software? Is there any improvements over Hornresp.Sorry i am new to TL.I just want to make the good one as soon as possible.
You cannot get Martin King's software anymore but it does allow better modeling of TLs than Hornresp I think(?). The actual line's length and its taper ratio create a longer effective length and its 1/4-wave resonant frequency, while the line's volume creates its bass reach. For the same 1/4-wave resonant frequency a tapered line will always be shorter than a non-tapered line. Your 160-cm long line with the 520/120 taper ratio will be just as good as a shorter 640/64 tapered line having the same volume, with the only real difference being in the smoothness of the response above several-hundred Hz, and since your design is intended to be a "subwoofer", those higher-frequency ripples aren't important.
Paul
Paul
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Ehem, sorry to intrude here, but it was supposed to be a subwoofer. This is the modeleled response from pkitt, with some remarks that I made. Notice the steep roll-off below Fs - impossible to eq up! Most two-way main speakers are also BR-tuned around 40-45Hz, so what is the benefit from this TL woofer?
Turkish traditional music has vast number of percussion and bass drums sound good only from sealed speakers. Ovbiously they will be driven with a plate-amp? Easy to set eq. Why not just make new slim and smaller sealed boxes for your SB34? Same width as your main speaker. Put the driver on the side, as low as possible. It should not start walking around because of the main speaker sitting on top of it.
Here discussion of ported vs. sealed vs. TL
Ported vs TL vs sealed
Turkish traditional music has vast number of percussion and bass drums sound good only from sealed speakers. Ovbiously they will be driven with a plate-amp? Easy to set eq. Why not just make new slim and smaller sealed boxes for your SB34? Same width as your main speaker. Put the driver on the side, as low as possible. It should not start walking around because of the main speaker sitting on top of it.
Here discussion of ported vs. sealed vs. TL
Ported vs TL vs sealed
Attachments
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Hi Juhazi 
Thank you for your comment.Yes the same idea was in my mind.SB34 seems more quality than eastech ones.But i heard and read that TL may sound better than sealed speakers.So i decided to make a TL.I sometimes listen to traditional Turkish music but not much.I like the sounds of drums and percussion very much though.Live sounds of them are very good.
I only knew about Winisd but learning something about Hornresp was also very useful for me in this time.Great free program.
In SB34 datasheet says minimum 100 liters box value so i thought if i make a slim box it may not sound very good.Maybe effective volume increases about 25% if i fill it with polyfiber.So 64 liters cabinet may behave like 80 liters so it may be ok then.
I made a 12dB PLLXO with styroflex caps from my caps store for free Crossing frequency is around 120Hz.And subwoofer amplifier is IRAUDAMP7 with bridged mode.And smps500r as power supply.I put it in an aluminium case and it sounds good.
When i compare eastech tower vs SB34 subwoofer ,TL tower sounds much thinner than SB34.But this trial box of TLs have 2:1 ratio and SD1 256cm2 and SD2 is 128cm2 approx.Maybe bigger box will give a deeper bass.
What do you think? If i buy better quality drivers(maybe ceramic SB 20cm white cone ones) 2 pcs of each TL with 64liters inside volume.How will they sound compared to same SB34 inside volume?Which of them would you prefer?
New ceramic drivers will cost about 500 euros plus tax and new SB34 woofer will only cost about 160 euros plus tax.Economy is not good here in Turkey nowadays.And does not seem it will be good in near future.
Thank you for your comment.Yes the same idea was in my mind.SB34 seems more quality than eastech ones.But i heard and read that TL may sound better than sealed speakers.So i decided to make a TL.I sometimes listen to traditional Turkish music but not much.I like the sounds of drums and percussion very much though.Live sounds of them are very good.I only knew about Winisd but learning something about Hornresp was also very useful for me in this time.Great free program.
In SB34 datasheet says minimum 100 liters box value so i thought if i make a slim box it may not sound very good.Maybe effective volume increases about 25% if i fill it with polyfiber.So 64 liters cabinet may behave like 80 liters so it may be ok then.
I made a 12dB PLLXO with styroflex caps from my caps store for free
Crossing frequency is around 120Hz.And subwoofer amplifier is IRAUDAMP7 with bridged mode.And smps500r as power supply.I put it in an aluminium case and it sounds good.When i compare eastech tower vs SB34 subwoofer ,TL tower sounds much thinner than SB34.But this trial box of TLs have 2:1 ratio and SD1 256cm2 and SD2 is 128cm2 approx.Maybe bigger box will give a deeper bass.
What do you think? If i buy better quality drivers(maybe ceramic SB 20cm white cone ones) 2 pcs of each TL with 64liters inside volume.How will they sound compared to same SB34 inside volume?Which of them would you prefer?
New ceramic drivers will cost about 500 euros plus tax and new SB34 woofer will only cost about 160 euros plus tax.Economy is not good here in Turkey nowadays.And does not seem it will be good in near future.
Sorry, I can't really comment the sound of TL bass because I have never heard those! But the fact that it has deep roll-off, more group delay than sealed, and high Fs in this case - no wonder it will sound thin.
A sealed big driver in a "too small" box just needs more equalization and thus power, but SB34 is a really good driver and can easily take hundreds of watts. Air spring protects it from over-excursion. I have just made 3-way speakers with SB29 in roughly 40 liter sealed boxes and they sound wonderful! I also have 10" SEAS L26ROY in 30 liter sealed box and they produce 20 Hz easily and 30Hz well above 100db (single unit).
With a small sealed box perhaps you should add an equalizing Linkwitz transform "booster" circuit to you diy amp. You should be able to make and set it easily. Many subwoofer palte-amps have similar low-end eq for sealed boxes, eg. Hypex DS2.0. DS2.0 is out of production, but many sellers still have them and they are easy to find second hand. (I have two of them in use).
Some day you will perhaps want to upgrade to active dsp-controlled 3-way diy speakers. You can start with your main speakers and subwoofers, dsp gives you the possibility to equalize both and set different crossovers and delays easily. If you want to change the sub or main speaker, just measure and set configurations again. Hypex FA boards and the money spent will never get wasted! I made a pair of 3-ways with FA123 for my daughter - thread here https://www.diyaudio.com/forums/multi-way/322839-seas-mr18-3-a-2.html#post5605246
In-room response here
A sealed big driver in a "too small" box just needs more equalization and thus power, but SB34 is a really good driver and can easily take hundreds of watts. Air spring protects it from over-excursion. I have just made 3-way speakers with SB29 in roughly 40 liter sealed boxes and they sound wonderful! I also have 10" SEAS L26ROY in 30 liter sealed box and they produce 20 Hz easily and 30Hz well above 100db (single unit).
With a small sealed box perhaps you should add an equalizing Linkwitz transform "booster" circuit to you diy amp. You should be able to make and set it easily. Many subwoofer palte-amps have similar low-end eq for sealed boxes, eg. Hypex DS2.0. DS2.0 is out of production, but many sellers still have them and they are easy to find second hand. (I have two of them in use).
Some day you will perhaps want to upgrade to active dsp-controlled 3-way diy speakers. You can start with your main speakers and subwoofers, dsp gives you the possibility to equalize both and set different crossovers and delays easily. If you want to change the sub or main speaker, just measure and set configurations again. Hypex FA boards and the money spent will never get wasted! I made a pair of 3-ways with FA123 for my daughter - thread here https://www.diyaudio.com/forums/multi-way/322839-seas-mr18-3-a-2.html#post5605246
In-room response here
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Sorry, I don't know where to go for that!
But it really looks like umut's project might not be a well done unit as a subwoofer - or what do you think?
Transmission line is also a resonant device. Perhaps a dipole isn't - until it is put in a room.
The Subwoofer DIY Page - Choosing a System
Data-Bass
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You shouldn't criticize TLs if you've never listened to a well-designed TL. Nevertheless, the primary reasons for the performance you so quickly criticized is due solely to the chosen driver with its high fs and high Qts as well as its small size. It would be possible to improve its bass performance simply by increasing the volume in the line, but with an Sd of 120 cm2, it's never going to truly be a subwoofer. I modeled what the OP modeled with different software primarily to confirm his modeling results were valid.
Paul
Paul
"You shouldn't criticize TLs if you've never listened to a well-designed TL"
When did I do that? I was commenting only the proposed case. I did state that I have never hear a bad or well designed TL subwoofer. Isn't that just the point here?
Where did I make a generalization? I can't understand your's or phivates's criticism
I quit this here now. umut, you can ofcourse send me a private message.
When did I do that? I was commenting only the proposed case. I did state that I have never hear a bad or well designed TL subwoofer. Isn't that just the point here?
Where did I make a generalization? I can't understand your's or phivates's criticism
I quit this here now. umut, you can ofcourse send me a private message.
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