im definitely ONLY interested in accurate sound.
distortion of any kind is something i want to avoid absolutely.
so what about using an 8 or 10 in driver in a bass horn?
smaller size, same high efficiency, smaller box, best sound?
Hi 60ndown,
"...all designs perform about the same."
If that's the case why bother asking about phase (or anything else as a matter of fact, just stuff that puppy in 4'x' board, and call it good)? Attached, please, find a SPL comparison of the RSS390HO in a tapped horn (@500W), and in a bass reflex enclosure (@800W). They don't perform the same, they are nowhere near the same size, be have differently under power, and if you would break down and fire up Hornresp you would see that their phase behaviour isn't the same either.
Regards,
"...all designs perform about the same."
If that's the case why bother asking about phase (or anything else as a matter of fact, just stuff that puppy in 4'x' board, and call it good)? Attached, please, find a SPL comparison of the RSS390HO in a tapped horn (@500W), and in a bass reflex enclosure (@800W). They don't perform the same, they are nowhere near the same size, be have differently under power, and if you would break down and fire up Hornresp you would see that their phase behaviour isn't the same either.
Regards,
Attachments
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and 120 is about 94% of 125, in this world.
unfortunately this world is also full of spiteful rude and sarcastic people.
the 'holier then thou' crew
serving no good to anyone but themselves.
and completely ignorant to the fact
that they behave that way
in the name of,
God.
then when something comes to light they dont like, they quickly *edit* it away hoping no one will notice....
God definitely notices everything.
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lilmikes 'how to tapped horn/hornresp' post
this is pretty awesome
Simple Tapped Horn Tutorial using Hornresp - AVS Forum
this is pretty awesome
Simple Tapped Horn Tutorial using Hornresp - AVS Forum
Not a side by side comparison, and the distortion observed in the Lab Sub was below the horn cut off, where a HP filter should be employed.
It does seem the push pull makes a difference in distortion below horn cutoff, but that seems rather academic, since a HP would eliminate the distortion while protecting the speaker from over excursion.
I edited nothing -- the moderators were kind enough to edit your offensive posts, not even at my request.
However, lets get back on topic, and put some math to this... as everyone is just guessing in the dark as to what you really want. You have a wo32 (corner loaded I'm assuming) and it has the recommended 10" drivers (again assuming) You are very happy with it, and it's crossed at 60hz to flatten off the rising response, so that you have (optimistic) somewhere between about 35-40hz up to about 120hz. At about 150 watts you are exceeding xmax by 2, so it's safe to assume that's driver damage territory and there is no way you are running that loud. At the most optimistic you are running 120db from 40-120hz at 1 meter. Your listening position is somewhere between -6db and -10db from your 1 meter level, meaning you are really listening to about 110db. (In reality, it's probably closer to 105db)
SO, lets put that outdoors, and you are listening at about 30-60 feet away. You need your 1 meter output to be about 23db above your 105-110, meaning your sub needs to put out 128-133db from 35hz-120hz.
That's no easy feat, and your little 12volt supply to an auto amplifier with your Karlson will not do it.
Your 120db = 125db comment shows that you haven't done any math.
please do us all a favor -- do the math, figure out what you want, and then ask questions.
You'll find lots of help, with no sarcasm or anything else off topic.
and no.... "and 120 is about 94% of 125, in this world...." it is not -- your ears hear log, not linear.
http://www.kemt.fei.tuke.sk/Predmety/KEMT320_EA/_web/Online_Course_on_Acoustics/hearing.html
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But you seem to notice little.
A 10 dB increase sounds twice as loud at around 1000 Hz.
Down at 20 Hz, it "only" takes 5 dB to sound twice as loud.
A 3 dB increase requires double the power .
A six dB difference requires four times the power, but when drivers are pushed hard, they heat up, and no longer will put out 3 dB or six dB more even if the power is available.
And if driven over excursion limits, drivers break. Many designs run out of excursion before power limits.
Regarding phase questions, no speakers are flat in phase response, below are a TH (blue), BR (purple), and AS (acoustic suspension, green) all with similar frequency response. A pair of C horns (orange) have a higher cutoff than the other three cabinets but the flattest phase response.
As long as the subs phase curve is matched to the top cabinet at the acoustic crossover point, the difference in phase response between the cabinets is not a big deal to my ears.
Art Welter
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Hi 60ndown,
The problem with dB is that it's so easy to get the numbers wrong. 3 dB is a 100% difference in power. In addition the models in the example (Post #15) are run @ a 300W difference in input power to begin with, that's another 2dB (from 500W to 800W). Just for fun I had Hornresp plot out both boxes with a 6dB input power difference, TH=200W/BR=800W, then the SPL curves are on about the same level. Naturally, the BR is still maxed out in power and Xmax, while the TH is now taking it considerably easier @ 1/4 max. power, and 7.3mm/35Hz excursion.
There has been a long discussion in the
http://www.diyaudio.com/forums/subw...ped-horn-project.html?perpage=25&pagenumber=1
pertaining to port losses, and there have been many discussions as to the very real power compression in the drivers, so the difference may be even a lot worse for the poor BR, but then, the TH is still in a much bigger box, and thus the BR may be much easier to lug back and forth, and nobody can tell you which sound you'll prefer.
Regards,
The problem with dB is that it's so easy to get the numbers wrong. 3 dB is a 100% difference in power. In addition the models in the example (Post #15) are run @ a 300W difference in input power to begin with, that's another 2dB (from 500W to 800W). Just for fun I had Hornresp plot out both boxes with a 6dB input power difference, TH=200W/BR=800W, then the SPL curves are on about the same level. Naturally, the BR is still maxed out in power and Xmax, while the TH is now taking it considerably easier @ 1/4 max. power, and 7.3mm/35Hz excursion.
There has been a long discussion in the
http://www.diyaudio.com/forums/subw...ped-horn-project.html?perpage=25&pagenumber=1
pertaining to port losses, and there have been many discussions as to the very real power compression in the drivers, so the difference may be even a lot worse for the poor BR, but then, the TH is still in a much bigger box, and thus the BR may be much easier to lug back and forth, and nobody can tell you which sound you'll prefer.
Regards,
Attachments
your math is excellent,
your understanding is non existent.
*if* you read my original posts (and try to understand them) you would know what im considering building,
"a single large subwoofer for occasional outdoor use" for fun, my life doesnt depend on it, a link to any good design (and a driver that works in it) would have been cool,
but no,
I HAVE TO LEARN HORNRESP
you dont understand/comprehend my inquiry = either you didnt read or didnt comprehend it.
i mentioned the wo32 in a private message to you a week ago, it hasnt been mentioned in any of my threads, except by you.
you told me once never to build one of your designs,
2 can play that game,
how bout you agree to never respond to any of my threads until you have read and can comprehend my request? (try reading it 3 or 4 times without a calculator in front of you)
seriously brother, in all the years (20) ive been on the www talking audio with people, you are the worst case of possessing a total inability to answer a simple question with a polite and helpful answer.
god forbid you ever pull over to *help* a woman with a flat tire, shed still be left in the dark and cold after you have explained to her the theory of relativity, and driven away not having actually fixed her tire.
im asking very basic questions about subwoofers, your telling me that im going to experience 'red shift' between 43hz and 38hz if i dont use 3 coats of polyurethane varnish on the 2nd and 5th corner of my horn.
i feel very sorry for your wife, she must require A LOT of medication.
your understanding is non existent.
*if* you read my original posts (and try to understand them) you would know what im considering building,
"a single large subwoofer for occasional outdoor use" for fun, my life doesnt depend on it, a link to any good design (and a driver that works in it) would have been cool,
but no,
I HAVE TO LEARN HORNRESP
you dont understand/comprehend my inquiry = either you didnt read or didnt comprehend it.
i mentioned the wo32 in a private message to you a week ago, it hasnt been mentioned in any of my threads, except by you.
you told me once never to build one of your designs,
2 can play that game,
how bout you agree to never respond to any of my threads until you have read and can comprehend my request? (try reading it 3 or 4 times without a calculator in front of you)
seriously brother, in all the years (20) ive been on the www talking audio with people, you are the worst case of possessing a total inability to answer a simple question with a polite and helpful answer.
god forbid you ever pull over to *help* a woman with a flat tire, shed still be left in the dark and cold after you have explained to her the theory of relativity, and driven away not having actually fixed her tire.
im asking very basic questions about subwoofers, your telling me that im going to experience 'red shift' between 43hz and 38hz if i dont use 3 coats of polyurethane varnish on the 2nd and 5th corner of my horn.
i feel very sorry for your wife, she must require A LOT of medication.
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Hey 60, when I followed Decware closely a few years back, I could tell you are a man of action with all the projects you flew through. People here are honestly trying to help. You absolutely cannot compare your request to changing a tire. Your request is not black and white or even shades of grey. There are so many colors possible to answer you that you seem to be overwhelmed. Most of the responses are trying to shed light on the complexity of choosing the right hardware for the job, given the restrictions on size/price/application, etc.
Make everything as simple as possible, but not simpler. ~Albert Einstein
Make everything as simple as possible, but not simpler. ~Albert Einstein
The distortion measurements below horn cutoff make it quite obvious that push-pull drive reduces distortion. That's where it is most apparent.
The fact that it is so effective below cutoff should be convincing evidence to you. Whether or not you care about distortion is up to you, but in my way of thinking, if I can employ both horn loading and push-pull drive to reduce distortion even more - in the passband - then that makes a better product.
Have you seen these charts? Lots of subs measured side by side, at high power levels:
Done any distortion charts of that Keystone sub you've built? I'd like to see charts of it at 100 watts, 200 watts, 400 watts, 800 watts and 1600 watts please. We have some Fitzmaurice subs in the measurements listed at the link above; Yours would be a nice addition.
thanks for the support 🙂
but i still believe there must be 3 or 5 or 9 well respected designs that would satisfy me,
it seems to me a lot of "audiophiles" have chronic,
*analysis paralysis*
you ever heard of someone buying a piece of equipment and selling it again
BEFORE EVEN USING IT? 😀
if someone wanted a simple cheap reliable car, id suggest a 1973 vw beetle or an early toyota pickup truck, both would fit the desired criteria.
even if every member on this forum and every other audio forum n the world had all bill gates money, and designed and built the very best portable subwoofer in the world,
its going to sound and perform differently in every room its used in.
and require some eq.
my math skills cant balance the change in my pocket,
but i KNOW thats true about subwoofers.
but i still believe there must be 3 or 5 or 9 well respected designs that would satisfy me,
it seems to me a lot of "audiophiles" have chronic,
*analysis paralysis*
you ever heard of someone buying a piece of equipment and selling it again
BEFORE EVEN USING IT? 😀
if someone wanted a simple cheap reliable car, id suggest a 1973 vw beetle or an early toyota pickup truck, both would fit the desired criteria.
even if every member on this forum and every other audio forum n the world had all bill gates money, and designed and built the very best portable subwoofer in the world,
its going to sound and perform differently in every room its used in.
and require some eq.
my math skills cant balance the change in my pocket,
but i KNOW thats true about subwoofers.
Dude you're asking everyone to do the work for you and insulting some of the most knowledgeable people here when they try to help you??? This stuff is all about math and physics. Why not take the time to figure it out yourself like allot of us have, or go buy an off-the-shelf product.
i believe in the easy and generous sharing of knowledge and resource, if i need some help i ask for it, in response, some people try and help, some try only to appear clever but help not at all.
when asked for help, i try and help easily and generously and as simply as possible.
KISS principle - Wikipedia, the free encyclopedia
if a person is unable or unwilling to help (even though they have everything they need to help) for some reason, or too afraid to give a clear/defined answer for fear of being found at fault by other *overly critical* forum members,
i often find a little prodding will bring them back to a better sense of reality.they may not admit it immediately and openly on a forum, but future responses from them may have a different tone.
i dont have time to study everything im interested in,
but ive got 5 hours and a few $$ to throw a nice sub together,
if i could just get agreement on the design.......
when asked for help, i try and help easily and generously and as simply as possible.
KISS principle - Wikipedia, the free encyclopedia
if a person is unable or unwilling to help (even though they have everything they need to help) for some reason, or too afraid to give a clear/defined answer for fear of being found at fault by other *overly critical* forum members,
i often find a little prodding will bring them back to a better sense of reality.they may not admit it immediately and openly on a forum, but future responses from them may have a different tone.
i dont have time to study everything im interested in,
but ive got 5 hours and a few $$ to throw a nice sub together,
if i could just get agreement on the design.......
i bet if i asked in the speaker forum if anyone could recommend a good respected time tested speaker id get some straight answers.
is a good and well respected subwoofer design so hard to recommend?
is a good and well respected subwoofer design so hard to recommend?
You will never know what box to build because they are all, at the very least, 'good' and all have their pro's and contras.
So build them all, buy one good driver and swap it between them!
So build them all, buy one good driver and swap it between them!
if i could just get agreement on the design.......
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