I don't think the thread starter is looking for some audiophile exotic construction. If you have a look at the 2x250W/100€ amp he uses, you see he is not looking for high end, but probably "much loud very cheap". If I'm wrong correct me.
Selling a sole chassis on eBay can work, selling self made, low craftmanship cabinests, doesn't.
If you are pleased with the cabinet, keep it and get a decend woofer, but before that, first explain what you want to use it for and what kind of music and SPL level.
A cabinet build without knowing what details to look for, may ruin the sound reproduction of the most expensive, capable driver. So post some pictures of your build, so we can match advice to your personality.
Concerning cabinets, we are not talking about some 2% lost quality, no one can hear, but not working as intended at all. So with cheap drivers, you have to take just as much care in building it as you should do for an expensive one. Maybe even more. This is a truth newbies and cheapies usualy don't like at all.
If you don't want to spent much money, you have to spent more on brain and manual work. If you want to save on planing and work too, you are wrong in DIYS.
You can get very good results from cheap speakers.
Most commercial build, not extremely expensive speakers, only use the cheapest chassis one can build.
Non the less your got to pick the right cheap chassis and put it into the best fitting cabinet to get an exeptable result. This is not a simple task, but a kind of art!
So if still interested, post some details.
Good luck!
Selling a sole chassis on eBay can work, selling self made, low craftmanship cabinests, doesn't.
If you are pleased with the cabinet, keep it and get a decend woofer, but before that, first explain what you want to use it for and what kind of music and SPL level.
A cabinet build without knowing what details to look for, may ruin the sound reproduction of the most expensive, capable driver. So post some pictures of your build, so we can match advice to your personality.
Concerning cabinets, we are not talking about some 2% lost quality, no one can hear, but not working as intended at all. So with cheap drivers, you have to take just as much care in building it as you should do for an expensive one. Maybe even more. This is a truth newbies and cheapies usualy don't like at all.
If you don't want to spent much money, you have to spent more on brain and manual work. If you want to save on planing and work too, you are wrong in DIYS.
You can get very good results from cheap speakers.
Most commercial build, not extremely expensive speakers, only use the cheapest chassis one can build.
Non the less your got to pick the right cheap chassis and put it into the best fitting cabinet to get an exeptable result. This is not a simple task, but a kind of art!
So if still interested, post some details.
Good luck!
I am not interested in using this box or woofer anymore, but i am interested in knowing what i did wrong so here is a link to some fotos i took earier. I can take fotos from the inside when im back home saturday. https://drive.google.com/drive/folders/1rsdgQLEVpwHJvOH62WIw6eBCRthwnJOZ
Lots of very good subs in 30 to 100 dollar range.
Very high Qts speaker was just a challenging one.
Would have to model the driver.
Having worked with High Qts 12" that will
barely do Qtc of 1.5 in 4 to 5 cubic feet.
My guess the 15" might be looking for
6 to 8 cubic feet.
High Qts will have a certain bloom
in a too small box.
Know that sound.
But in a large enough sealed box
is actually rather pleasing.
Overall very deep bass in sealed box.
The tradeoff, very low sensitivity.
Not considered a sub in traditional sense.
So can understand the frustration.
Next endeavor could suggest different
low cost drivers, for a traditional
bass reflex sub
Very high Qts speaker was just a challenging one.
Would have to model the driver.
Having worked with High Qts 12" that will
barely do Qtc of 1.5 in 4 to 5 cubic feet.
My guess the 15" might be looking for
6 to 8 cubic feet.
High Qts will have a certain bloom
in a too small box.
Know that sound.
But in a large enough sealed box
is actually rather pleasing.
Overall very deep bass in sealed box.
The tradeoff, very low sensitivity.
Not considered a sub in traditional sense.
So can understand the frustration.
Next endeavor could suggest different
low cost drivers, for a traditional
bass reflex sub
What i could not find in this thread if you actually use a crossover?
A passive filter or something active? Or just the amplifier directly connected to the speaker?
A passive filter or something active? Or just the amplifier directly connected to the speaker?
It looks like something got entered incorrectly into WinISD, or else WinISD is predicting the wrong response for this set of parameters. I used a different modeler, based on Jeff Bagby's WBCD spreadsheet, and it predicts a peak around 54Hz. I tried playing with the parameters to replicate your 29Hz peak but couldn't get that same result.
As others have pointed out, this type of driver is more suited for PA applications, where a 60Hz peak isn't as important as the midrange performance.
The only thing you seem to have done wrong is the data entry issue mentioned by Davor D, kouiky, Turbowatch2 & Neil Davis.
Here is the response of the driver, using exactly the parameters from the soundimports page you linked to in 113l (ie 4 cu ft) tuned with the stated port, and WinISD's default assumption of Box Ql = 10.
Note how similar the frequency and magnitude of the peak are to Davor D's hornresp sims from page 1.
I'll also attach a zip with the WinISD driver and project file - I've thrown a little bit of EQ at it to see what it might be capable of here too:
Depending on your priorities, you might go even more aggressive with the EQ, trading off a bit more SPL for more extension:
HTH,
David
Then it isn't surprising it doesn't sound like a subwoofer. The driver is trying to play the whole frequency range, and not just the part it is supposed to do..
Sorry, just realised one more thing I should have added before - your port is probably tuned lower than predicted by WinISD due to the end correction factor mentioned by Davor D.
WinISD assumes that the internal end of your port is at least one port diameter away from the sides and back of the box. A slot port like you have built does not meet this criteria, and the extra extension of 3 out of the 4 port walls essentially means it will tune lower. The common way to deal with this is to manually calculate the correct port length using a different end correction factor. Former forum member Bjorno gave this graphic with the equations and factors to use:
So, your port is likely tuned around 25Hz, which very slightly reduces the height and frequency of the peak compared to my earlier post - sorry for missing that out before.
Cheers,
D.
WinISD assumes that the internal end of your port is at least one port diameter away from the sides and back of the box. A slot port like you have built does not meet this criteria, and the extra extension of 3 out of the 4 port walls essentially means it will tune lower. The common way to deal with this is to manually calculate the correct port length using a different end correction factor. Former forum member Bjorno gave this graphic with the equations and factors to use:
So, your port is likely tuned around 25Hz, which very slightly reduces the height and frequency of the peak compared to my earlier post - sorry for missing that out before.
Cheers,
D.
As I previously suggested, if you could kindly take a screenshot of the T&S parameters with the WinISD file open, we might be able to spot the error. It could be one decimal point that lead to this.
The box is still good and just to share the point, with a more expensive and purpose-designed subwoofer, it could easily go into the 20’s. Drivers like the Hi-Vi SP10 or several versions of woofers from SB Acoustics need more power, but can go very deep.
Nice post.
FWIW, it might be tuned even lower than that, as apparently using that vent length calculation could lead to calculated vent lengths that are too long anyway. See http://troelsgravesen.dk/vent_tuning.htm
All you did wrong was picking a useless woofer. Here are people that have spent half a lifetime or more on speaker building.
They can come up with some exotic, experimental solution to make this ill camel play some lower notes.
Honestly, in practice such tricks will work, but have severe side effects. Like extreme need of amplifier power, low SPL output and extra devices, like a DSP.
To say it simple, no one knowing basics of loudspeaker construction would have choosen this speaker for any cause.
You can compare it to building a boat from brick's and mortar. You may make it float, but it makes no sense.
That is what you did wrong. Your mistake with the TSP data was just some cream on the cake.
PS your cabinet looks useable. You will have to shorten the vent for a decent woofer, but the rest seems quite solid.
They can come up with some exotic, experimental solution to make this ill camel play some lower notes.
Honestly, in practice such tricks will work, but have severe side effects. Like extreme need of amplifier power, low SPL output and extra devices, like a DSP.
To say it simple, no one knowing basics of loudspeaker construction would have choosen this speaker for any cause.
You can compare it to building a boat from brick's and mortar. You may make it float, but it makes no sense.
That is what you did wrong. Your mistake with the TSP data was just some cream on the cake.
PS your cabinet looks useable. You will have to shorten the vent for a decent woofer, but the rest seems quite solid.
I can't really send the winisd project right now (since im not home), but i think the thing thats clear is that i probably made an error in entering the perrameters. Ill check them saturday when im home again. And i also didnt even know that qts was such an big number.....🤡💩💀👶
Now that ive wached some videos on youtube about qts i feel the same way.. IDIOT ME!💀
Some new to loudspeakers may not know this, but if you simulate with the right data, you have a 99% chance of getting exactly the speaker you predict.
I started using TSP around 1985, when I read about it on some English publication. I had a programable calculator and wrote a simple basic program for closed and a more compilcated for vented cabinets. Most DIYS and a lot of so called professionals didn't trust these tools. Only problem at the time where unreliable TSP parameter. Since then I never build a project where the bass did not turn out as expected.
At that time many speakers where sold with data like 30-60l closed, 50-80l vented. People bought them and tried to get them right by try and error. Electronics dealer sold speaker chassis and put "universal 4-8 Ohm x-over with 12dB 800-3000Hz" on top. The results where very mixed as some may remember.
Today we can simulate even the angles of a speaker baffle with the right software. Many DIYS speaker builds beat any commercial product even ten times as expensive. Speaker development is not a dark art of some industry wizzards any more.
The times of guess, try and error are over. Today you can see what you will get, before you buy and build.
I started using TSP around 1985, when I read about it on some English publication. I had a programable calculator and wrote a simple basic program for closed and a more compilcated for vented cabinets. Most DIYS and a lot of so called professionals didn't trust these tools. Only problem at the time where unreliable TSP parameter. Since then I never build a project where the bass did not turn out as expected.
At that time many speakers where sold with data like 30-60l closed, 50-80l vented. People bought them and tried to get them right by try and error. Electronics dealer sold speaker chassis and put "universal 4-8 Ohm x-over with 12dB 800-3000Hz" on top. The results where very mixed as some may remember.
Today we can simulate even the angles of a speaker baffle with the right software. Many DIYS speaker builds beat any commercial product even ten times as expensive. Speaker development is not a dark art of some industry wizzards any more.
The times of guess, try and error are over. Today you can see what you will get, before you buy and build.
China Garbage !! Why bother !
I won't buy any PE stuff , all garbage. they sold out. dayton taiwan is better , china is junk. No dayton usa , except old stock.
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I buy plenty of “PE stuff”. A lot of B&C, Eminence, and Selenium/PRV from there…. And a few Dayton made in Tiawan, and even Dayton made in China. But you have to be realistic in what to expect for your money. $35 doesn’t buy much these days, except maybe a small midrange. Those were just simply intended to be used in “rack stereo” speaker boxes - that is, as big a box as tolerable and live with the bass you get. Those old systems had 20 watts tops, so you never needed 20+ mm of x-max.
What you could get years ago were some fairly decent 8’s and 10’s - with Q’s in the 0.5 to 0.8 range, and put out a satisfying bass response to the 50’s or 60’s in one or two cubic feet sealed. Even as high as 90dB/W. Their only weaknesses were x-max’s in the 3mm range. When all you has was 20 to maybe 50 watts, that’s all that was needed. Those old designs have disappeared from the market. Too big a box for a main speaker, and not enough x-max for a dedicated sub. But they were under $35.