Challenges I faced with getting "good" off axis measurements.
* at first I didn't take into account the rotation axis. It really needs to be in line with the front baffle.
* up to 90 deg was ok. getting to 180 deg my yard (measuring outside) is not big enough and I get irregularities in the measurements greater than 120 deg.
* my turntable is not good enough for measurements past about 90 deg. It starts to droop when it goes past there. A Low Cost Speaker Testing Stand
I had three attempts at getting some decent off axis measurements (through 180 deg) for doing a new crossover, but in the end didn't use them, due to the above mentioned issues. I guess I could go ahead with up to around 100 deg as it is better than just on axis.
I modeled the current crossover with the taken off axis measurements in vituixcad and compared to actual off axis measurements using that implemented crossover and did not get a good correlation, so decided that I still had work to do.
In the end that is my yardstick. If there is not good correlation between actual measurements and simulations based on actual measurements, then something is awry.
Attached are the last attempt I made of one of my tweeters. 1st is on axis through 90 deg in 10 deg increments.
2nd is 90deg through 180 deg in 10 deg increments.
To me the second lot are too all over the shop (probably due to reflections off the fence (broken up by shrubs). If I had a wide open space and a better turntable then maybe I could get the 180 deg (or even full 360 deg) measurements satisfactorily.
Tony.
* at first I didn't take into account the rotation axis. It really needs to be in line with the front baffle.
* up to 90 deg was ok. getting to 180 deg my yard (measuring outside) is not big enough and I get irregularities in the measurements greater than 120 deg.
* my turntable is not good enough for measurements past about 90 deg. It starts to droop when it goes past there. A Low Cost Speaker Testing Stand
I had three attempts at getting some decent off axis measurements (through 180 deg) for doing a new crossover, but in the end didn't use them, due to the above mentioned issues. I guess I could go ahead with up to around 100 deg as it is better than just on axis.
I modeled the current crossover with the taken off axis measurements in vituixcad and compared to actual off axis measurements using that implemented crossover and did not get a good correlation, so decided that I still had work to do.
In the end that is my yardstick. If there is not good correlation between actual measurements and simulations based on actual measurements, then something is awry.
Attached are the last attempt I made of one of my tweeters. 1st is on axis through 90 deg in 10 deg increments.
2nd is 90deg through 180 deg in 10 deg increments.
To me the second lot are too all over the shop (probably due to reflections off the fence (broken up by shrubs). If I had a wide open space and a better turntable then maybe I could get the 180 deg (or even full 360 deg) measurements satisfactorily.
Tony.
Attachments
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This is mostly OT so just shortly with sorry.
"Something better" is quite abstract. Journey could also sound just series of mistakes and pain in the a** producing lots of garbage with short life time. See also the following answer.
Our diy history is quite irrelevant. Typical case is that experienced members are giving instructions for beginners hoping to get as good sound quality as possible. Modern life style is also busy so another wish or requirement is to design speakers without wasting too much time. Listing our learning curve, all mistakes, wrong or missing tools and methods could be fun self-ironic background information, but it does not provide immediate and direct help to any problem or question.
My policy is to hit right on target; as good and fast as possible - especially when giving instructions and recommendations to someone else. Reliable and comprehensive data, and fast and sustainable design.
I have also seen that rookie has succeeded with WWMTMWW+sub design including horizontal off-axis measurement data 0-160 deg. It's really not that difficult. Main problems are prejudices and traditions. "Fake news" and "nationalists" on discussion forums maintaining poor vintage traditions and recommending limited tools.
This is international forum is English only. The same language for all has advantages of course, but causes clear unequality too. Writing is easier and faster for native English so their messages have much more weight due to message count and length. The others (like me) get tired quite fast and total information will be biased by active English writers.
So it's important (imo) that experienced native English realize this difference and try to be as responsible as possible: recommend methods and tools for enabling very good result as fast as possible. Not listing or recommending anything they just use due to some personal opinion or limit knowing that it does not provide adequate information for evaluating sound while design phase.
By containing poor methods and tools. Problem is that we need some agreement what is good, adequate, flexible etc. Or the opposite: what is poor, inadequate and limited. We probably have different opinions and experience, but there is well known science available for making basic decisions. For example:
* Delete and ignore everything based on axial response only without directivity and acoustic power. Some exceptions are probably needed to enable simulation of e.g. horns before making expensive or difficult prototypes.
"Something better" is quite abstract. Journey could also sound just series of mistakes and pain in the a** producing lots of garbage with short life time. See also the following answer.
Our diy history is quite irrelevant. Typical case is that experienced members are giving instructions for beginners hoping to get as good sound quality as possible. Modern life style is also busy so another wish or requirement is to design speakers without wasting too much time. Listing our learning curve, all mistakes, wrong or missing tools and methods could be fun self-ironic background information, but it does not provide immediate and direct help to any problem or question.
My policy is to hit right on target; as good and fast as possible - especially when giving instructions and recommendations to someone else. Reliable and comprehensive data, and fast and sustainable design.
I have also seen that rookie has succeeded with WWMTMWW+sub design including horizontal off-axis measurement data 0-160 deg. It's really not that difficult. Main problems are prejudices and traditions. "Fake news" and "nationalists" on discussion forums maintaining poor vintage traditions and recommending limited tools.
This is international forum is English only. The same language for all has advantages of course, but causes clear unequality too. Writing is easier and faster for native English so their messages have much more weight due to message count and length. The others (like me) get tired quite fast and total information will be biased by active English writers.
So it's important (imo) that experienced native English realize this difference and try to be as responsible as possible: recommend methods and tools for enabling very good result as fast as possible. Not listing or recommending anything they just use due to some personal opinion or limit knowing that it does not provide adequate information for evaluating sound while design phase.
By containing poor methods and tools. Problem is that we need some agreement what is good, adequate, flexible etc. Or the opposite: what is poor, inadequate and limited. We probably have different opinions and experience, but there is well known science available for making basic decisions. For example:
* Delete and ignore everything based on axial response only without directivity and acoustic power. Some exceptions are probably needed to enable simulation of e.g. horns before making expensive or difficult prototypes.
Kimmo - you definitely bring up some very good points. One point I want to address is this
I think you underestimate how much weight and impact your writings on this forum have. There are many contributors on this site, but we are not equal in our expertise. You are in a very small group at the upper echelon of credibility and knowledge. So even if English language is more work for you, I guarantee that every word you write is carefully read and studied. Personally, I find your contributions to be extremely valuable.
I think you underestimate how much weight and impact your writings on this forum have. There are many contributors on this site, but we are not equal in our expertise. You are in a very small group at the upper echelon of credibility and knowledge. So even if English language is more work for you, I guarantee that every word you write is carefully read and studied. Personally, I find your contributions to be extremely valuable.
You have made 2 things wrong, applied neither baffle step response/diffraction, nor time delay to woofer. If you did, it would have resembled a lot better to the second graph you posted.
First of all thank you everyone for your answers,
after carefully reading I decided on building a proven design as my first speaker.
The Crossover I designed indeed used the provided graphs from Dayton which as many of u have pointed out will be quite different in a build enclosure.
I am planning on building the Classix II since I am mostly listening to HipHop and many say it is well suited for that style of music.
Is there another design around the same price range which I should take into consideration?
after carefully reading I decided on building a proven design as my first speaker.
The Crossover I designed indeed used the provided graphs from Dayton which as many of u have pointed out will be quite different in a build enclosure.
I am planning on building the Classix II since I am mostly listening to HipHop and many say it is well suited for that style of music.
Is there another design around the same price range which I should take into consideration?
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Thanks Loizek, that's quite right: unfortunately I haven't worked out how to apply time delay and diffraction to Xsim. I guess the point of my exercise is to show how it's critical to use measured in-box data.
Will see if I can work those things out and see how they affect the sims.
Cheers
Geoff
The Classix II are excellent speakers for the price, you can check out the many reviews; we love ours. If you wanted a floor stander and could afford another pair of the woofers, the Classix 2.5s may be a better choice: they're more efficient and Paul says they have a better mid range than you'd expect from the DC160. The Vifa BC25 is a really nice tweeter, I've used them in three projects.
If you do go with the IIs, perhaps consider making speaker grilles as the DC160 isn't the most attractive looking driver. I'd also suggest using stands, but that will apply to most other designs you might be considering.
What's your room size, please? I ask because the DC160 can run out of puff on some program material if you push them too hard in a larger room. Usually, no problem; small to medium room, should be fine. In a larger room, say over 20' x 20', I'd be inclined to go for the 2.5s.
As Paul says on his website, the Classix II work really well with less well recorded or mixed music. We don't listen to hip hop, so don't know if it falls into those categories, but things like 50s to 70s jazz, early Beatles and Stones etc sound great. Parts Express and Meniscus Audio sell the Classix kits and there are many product reviews to peruse.
Alternatively, there are many proved, well regarded designs and kits - some with knock-down cabinets - for 6"-6.5" two ways out there, so your problem may be which one to choose for your budget. And speaking of budget, where do you live?
I ask because in Australia the price of Dayton drivers relative to other brands has increased significantly due to the decline of the $A against the $US, this makes the DC160 less of a value proposition: when I built my Classix II they were $40 each, now $60 each, which puts them up with some stiff competition. Having said that, the Classix II are still great speakers and very good value.
You will receive many suggestions I am sure. Take your time, read the designers' write-ups and build reviews and enjoy the journey!
Geoff
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Kimmo, perhaps you misunderstand the intent of the content that has come so far in the thread. If you want to continue to discuss we could take it to the discussion thread. Design your own speaker from scratch discussion thread
Sorry Geoff for the off topic. I hope we haven't put you off. Whatever you do the most important thing is to learn from it
Tony.
Sorry Geoff for the off topic. I hope we haven't put you off. Whatever you do the most important thing is to learn from it
Tony.
My room is about 15m² big, so quite mediocre and I don't listen to music that loud anyway.
I am from the EU where most hardware in comparison to parts-express is about 10% more expensive, so it is not that big of a problem.
I have also looked into the Samba Speaker which looks quite promising, anyone here built it / can say something about it?
I haven't heard the Sambas, which use a Dayton RS180P-4 mid and Dayton RST28F tweeter. However, we have pair of "Slapshot" MTMs which use the RS180P (8 ohm version) but a Morel tweeter and they sound great: very detailed, excellent bass - they have more 'Xmax" than the DC160 - and as a bonus they look space-age.
The RS180P will show up faults in recordings, but on the other hand, you hear a bit more of the music and they're a bit 'cleaner'. I could best describe the difference between the speakers as a bit like listening to CD vs LP.
Ideally, I would like a pair of the Classix 2.5s next to my MTMs and switch between the two, using the Classix for older recordings. That's not going to happen....
Value wise, Parts Express has the Classix with baffle only for US$85 and the Samba with baffle only on sale for for US$109, so the price difference isn't that much. Here, the parts for the Samba are over twice the price of the Classix, so you're lucky.
It's your choice, of course, I think you would be happy with either. Fewer people have built the Sambas than the Classix, but for one thing, they haven't been on the market as long and they're only sold through Parts Express.
There are other excellent kits and projects around, by all means wait for some more ideas from Forum members.
Geoff
The RS180P will show up faults in recordings, but on the other hand, you hear a bit more of the music and they're a bit 'cleaner'. I could best describe the difference between the speakers as a bit like listening to CD vs LP.
Ideally, I would like a pair of the Classix 2.5s next to my MTMs and switch between the two, using the Classix for older recordings. That's not going to happen....
Value wise, Parts Express has the Classix with baffle only for US$85 and the Samba with baffle only on sale for for US$109, so the price difference isn't that much. Here, the parts for the Samba are over twice the price of the Classix, so you're lucky.
It's your choice, of course, I think you would be happy with either. Fewer people have built the Sambas than the Classix, but for one thing, they haven't been on the market as long and they're only sold through Parts Express.
There are other excellent kits and projects around, by all means wait for some more ideas from Forum members.
Geoff
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I'm going to respond in wintermute's thread - Design your own speaker from scratch discussion thread
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