Putting this together now, but not open baffle due to aesthetics.
I can still change it at this point:
This GRS sounded fine open baffle crossed at 300 Hz on my table.
The Dayton RS52AN did not sound as good, especially in the low end, which was surprising to me.
Why does Zaph write this about the B&G neo3 :
"Note: these were tested with the rear chamber in place. Later, with a different pair, I also tested with the chamber removed. The tweeter was far too overdamped in that case, and I recommend leaving the rear chamber installed."
Why is overdamped bad?
Is GRS like this?
Marketing claims GRS PT6816-8 is for "open-baffle" "line array".
My enclosure is almost done.
If you want 20 Hz to 1 KHz, it seems to be a good choice.
Seas has more detail and my metal grill fits over it.
I can still change it at this point:
Will it sound like ****?
Also when it's open baffle it's radiating surface is 104 cm^2 instead of 52 cm^2.This GRS sounded fine open baffle crossed at 300 Hz on my table.
The Dayton RS52AN did not sound as good, especially in the low end, which was surprising to me.
Why does Zaph write this about the B&G neo3 :
"Note: these were tested with the rear chamber in place. Later, with a different pair, I also tested with the chamber removed. The tweeter was far too overdamped in that case, and I recommend leaving the rear chamber installed."
Why is overdamped bad?
Is GRS like this?
Marketing claims GRS PT6816-8 is for "open-baffle" "line array".
My enclosure is almost done.
SB Acoustics SB23CACS45-4 8" ceramic woofer- 4 ohms is also a great woofer
SB is more for bass and build quality is really nice.If you want 20 Hz to 1 KHz, it seems to be a good choice.
Seas has more detail and my metal grill fits over it.
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I think he meant the response had a more extended/gradual roll-off toward the low frequencies, but I'm assuming. If this shortens the response area that's flat, it complicates crossover design or limits the usable range. Another post here:
https://www.diyaudio.com/community/threads/fyi-zaphaudio-new-ribbon-tests.69037/page-4
"I pulled the rear chambers off my pair last night also. It was severely overdamped without one. Reponse was still relatively smooth but tilted down and extended to about 600hz."
Any foil driver should be tested with pink noise , 1/3 octave wide . With pink noise there is no masking above and below the intended narrow noise signal .
1W RMS is enough power to detect distortion artifacts by ear .
No filter needed but bandwith center frequency should be around 400 to 2000Hz .
Please report here any defects of this driver (pair?) , thanks!
1W RMS is enough power to detect distortion artifacts by ear .
No filter needed but bandwith center frequency should be around 400 to 2000Hz .
Please report here any defects of this driver (pair?) , thanks!
Okay, going for the rear chamber, since I already started on the baffle and it will look better.
How big should I make the rear chamber for the GRS?
Should I make it tapered curve?
I have the board in the pic cut in half.
You can make the same shape as B&G driver or you can flip them and make it into a point.
Should I do that?
Or what would be easier is to just make the back flat and add wavy rubber and wool to the back.
Pic also attached. It's a rubber wave form shape and then wool or something on top.
Should I do that?
I haven't measured drivers in 20 years maybe.
"You can't listen to a graph."
Banned from DIY audio I think, "Dickman" was his "surname" or "Diekman"
I think.
GRS in open baffle is excellent solution to simplify cross over and ruin down to 300-600 Hz
There really isn't anything interesting above 3-4 KHz
Shows you how bad some measurements and tweeters are.
This thing has a giant peak at 8 KHz, doesn't bother me at all.
Off axis response terrible, in one direction, no problem.
Every dome driver/tweeter I have ever heard, sounds worse.
And tweeters they only play to 1.5 KHz maybe.
So basically no 8" woofer 2-way option.
You can cross these over to 8" SB "ceramic" woofer with 6-7 x-over components and they will play down to 20 Hz at 83-85 Db in 35 liter box.
WITH A LOT OF BASS. But I don't have a metal grill for SB at the moment, also you could say the SEAS has more detail and I DO NOT really need a lot of bass.
You can listen to electronic music (drum bass) or jazz or classical.
Audiophiles:
"OH, hey listen, all you have to do is put a notch in the x-over".
I do NOT want to do that.
"Just fill your box up with 20+ x-over parts." No thank you.
"Look at my sexy passive cross over part pics." No thank you.
"I just screwed my woofers into the speaker with no washers and wood screws". No thank you.
"Dayton RS woofers look sexy" No they don't.
SB Acoustics is sexy.
Also why you worried about slight distortion when you have HUGE distortion below 60 Hz at 90 Db?
Measurements are important, especially when it comes to health and safety but I'm trying not to make measurements my religion.
I value simplicity.
A lot of people can make it complex and great, but can you make it simple and great?
Also 3" and 8-10" is pretty good.
Just GRS is more interesting and comes with a grill. But seems fragile.
How big should I make the rear chamber for the GRS?
Should I make it tapered curve?
I have the board in the pic cut in half.
You can make the same shape as B&G driver or you can flip them and make it into a point.
Should I do that?
Or what would be easier is to just make the back flat and add wavy rubber and wool to the back.
Pic also attached. It's a rubber wave form shape and then wool or something on top.
Should I do that?
I haven't measured drivers in 20 years maybe.
"You can't listen to a graph."
Banned from DIY audio I think, "Dickman" was his "surname" or "Diekman"
I think.GRS in open baffle is excellent solution to simplify cross over and ruin down to 300-600 Hz
There really isn't anything interesting above 3-4 KHz
Shows you how bad some measurements and tweeters are.
This thing has a giant peak at 8 KHz, doesn't bother me at all.
Off axis response terrible, in one direction, no problem.
Every dome driver/tweeter I have ever heard, sounds worse.
And tweeters they only play to 1.5 KHz maybe.
So basically no 8" woofer 2-way option.
You can cross these over to 8" SB "ceramic" woofer with 6-7 x-over components and they will play down to 20 Hz at 83-85 Db in 35 liter box.
WITH A LOT OF BASS. But I don't have a metal grill for SB at the moment, also you could say the SEAS has more detail and I DO NOT really need a lot of bass.
You can listen to electronic music (drum bass) or jazz or classical.
Audiophiles:
"OH, hey listen, all you have to do is put a notch in the x-over".
I do NOT want to do that.
"Just fill your box up with 20+ x-over parts." No thank you.
"Look at my sexy passive cross over part pics." No thank you.
"I just screwed my woofers into the speaker with no washers and wood screws". No thank you.
"Dayton RS woofers look sexy" No they don't.
SB Acoustics is sexy.
Also why you worried about slight distortion when you have HUGE distortion below 60 Hz at 90 Db?
Measurements are important, especially when it comes to health and safety but I'm trying not to make measurements my religion.
I value simplicity.
A lot of people can make it complex and great, but can you make it simple and great?
Also 3" and 8-10" is pretty good.
Just GRS is more interesting and comes with a grill. But seems fragile.
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Maybe I should make the chamber larger than I thought:
https://www.rob-elder.com/LouC/speakers/Neo83/Neo8Neo3.html
"(Roughly 8 X 3 X 3 internal dimensions)" dimension in inches
https://www.rob-elder.com/LouC/speakers/Neo83/Neo8Neo3.html
"(Roughly 8 X 3 X 3 internal dimensions)" dimension in inches
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Okay, seems like these need a larger chamber than I thought:
https://www.diyaudio.com/community/threads/fyi-zaphaudio-new-ribbon-tests.69037/page-4
https://www.diyaudio.com/community/threads/fyi-zaphaudio-new-ribbon-tests.69037/page-4
Not sure what you're goals are here but it would make sense to me to run the GRS open baffle to 1khz and cross to an 8" woofer there.......add a bit of horn loading to the GRS and match the directivity to the woofer.....would be a fantastic open baffle MT section over a boxed woofer at 100-120hz or so.
You should definately consider raising the crossover point btw the woofer and the Slim 8. It's distortion rises significantly below 800hz. And this is NOT just graph watching, it CAN be heard. You will experience a forward or shouting midrange presentation even if adjusted to measure flat. Regarding the 8Khz peaking, if that doesn't bother you, maybe this won't eiether, so to each his own. You may like the extra clarity or detail you hear from this top end boost, but for many listeners this becomes fatiguing over time.
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Almost done hopefully.
This guy -- https://www.rob-elder.com/LouC/speakers/Neo83/Neo8Neo3P3.html -- says it doesn't sound better open baffle.
I would have thought it sounded better open baffle, also, but I guess people have different opinions.
Also the aesthetics of open baffle suck *** according to most persons' humble opinions, including mine, but it's not too bad if it sounds (way) better.
Interesting.
Raise it to what frequency?
Where did you get that fantasstish graph?
I had it playing on my counter open baffle just tilled up about 60 degrees, next to a tilled DAYTON RS52AN-08 both high passed at 320 Hz 12/db octave.
The RS52 sounded like a small woofer playing in a small box at the low end and the GRS sounded fine I thought.
So I figure 800 Hz would be okay, guess I was wrong.
Both sounded great though.
I thought with the GRS I could hear the music more accurately and could also hear more detail in the music.
Sirens for example sounded life-like.
Most people are familiar with what sirens sound like.
Maybe human voices too.
About the large peak at 8-12 KHz.
After listening to sound, not looking at graphs (insert mind blown emoji here) I have to agree with another person on DIYaudio, that the peak on a or this AMT driver is not irritating.
"Wouldn't worry too much about the 12khz hump as it's really not there with music"
I think the 300 Hz bump is supposed to be attenuated by the enclosure I built, according to the website I linked to:
https://www.rob-elder.com/LouC/speakers/Neo83/Neo8Neo3P3.html
Hopefully it is the right size, but I can make it smaller.
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That's why i asked your goals.....open baffle is a different thing......and for the folks that can place their speakers out into the room 2 meters, it just doesn't get any better than a well executed mid-treble solution......i'll stand by that statement inside out.
Not sure about the driver sounding 'better' due to the loading......more likely the overall alignment didn't work for the fella.
Not sure about the driver sounding 'better' due to the loading......more likely the overall alignment didn't work for the fella.
The measurement is my own, performed at the same time I did a planar measurement series with all of the PE drivers when they were newly released and compred them to original BG models and the Radian drivers that were coming out at the time. My measurements begin on page 5, but there's good info all the way through the thread.
https://www.diyaudio.com/community/threads/new-planar-drivers-at-parts-express.360339/page-5
I think several of us thought that you were crossing at 300hz because that's what you mentioned in you initial post, but I see now from your graphs that it looks like you're closer to 800hz, which is good. As to the "detail" you like, I'll say again, elevated treble always gives the perception of detail. It's not accurate though. You may not care much for measurements, but there's a reason well designed speakers generally follow a similar freq response profile and that those same speakers are generally preferred in blind testing as performed by Harman. If you find that only certain styles of music suit your speakers, that's a sign that their freq response is not great.
https://www.diyaudio.com/community/threads/new-planar-drivers-at-parts-express.360339/page-5
I think several of us thought that you were crossing at 300hz because that's what you mentioned in you initial post, but I see now from your graphs that it looks like you're closer to 800hz, which is good. As to the "detail" you like, I'll say again, elevated treble always gives the perception of detail. It's not accurate though. You may not care much for measurements, but there's a reason well designed speakers generally follow a similar freq response profile and that those same speakers are generally preferred in blind testing as performed by Harman. If you find that only certain styles of music suit your speakers, that's a sign that their freq response is not great.
This is why I'm kind of starting to hate graphs.
I spend a lot of time looking at graphs.
It's kind of good and bad.
The B&G neo8-PDR and Neo8 and GRS 8 all look excellent.
Slim looks okay.
That's kind of the downside of being "smart" is over analyzing everything.
It's not really even smart it's just training your brain to be active in one sense and then passive in another.
I guess I'll look for a B&G and GRS 8 real quick.
If I can't find any I'll just move forward with the GRS8 slim.
Even with the speaker fully glued together I can still route the hole bigger for a neo8 or GRS8.
DIY audio is kind of about building what the individual likes.
I mean in the "what is the universe expanding into?" thread on here, I seem to be the only one questioning the expansion premise.
If that tells you anything.
The observable universe is 93 billion lightyears across and a few years ago people were claiming (maybe still are) that the universe is 13-14 billion years old.
That's just 1 of 100 counterpoints to expansion.
Example -- SB satori woofers/drivers measure the best.
Many people don't like them because they are not detailed or slow or some other reasons.
I like them, but I'm not a real audiophile.
They are slow woofers that go deep.
Look at CSD or pulse/step response.
But with tweeters the CSD/step don't seem to tell you how they will sound too much maybe.
No matter how much you know, the amount of information you don't know is always infinite.
Tests are there to tell you how something might perform, not how something will perform.
Also you're dealing with psychoacoustics, that's a real word? Wow. Thought I made it up.
That's why I bought the best 2-ways made by Joe D. a few years back and I liked the sound of Bose 301's better.
Usher 8948a and 9950.
Joe D.: "let me measure them for you". My reply: "No, thank you."
The possibility that Bose isn't all just marketing is less than 0%, just like with everything.
There isn't much information in the 2-4 KHz plus range.
I do like blind A/B testing the best though.
I spend a lot of time looking at graphs.
It's kind of good and bad.
The B&G neo8-PDR and Neo8 and GRS 8 all look excellent.
Slim looks okay.
That's kind of the downside of being "smart" is over analyzing everything.
It's not really even smart it's just training your brain to be active in one sense and then passive in another.
I guess I'll look for a B&G and GRS 8 real quick.
If I can't find any I'll just move forward with the GRS8 slim.
Even with the speaker fully glued together I can still route the hole bigger for a neo8 or GRS8.
DIY audio is kind of about building what the individual likes.
I mean in the "what is the universe expanding into?" thread on here, I seem to be the only one questioning the expansion premise.
If that tells you anything.
The observable universe is 93 billion lightyears across and a few years ago people were claiming (maybe still are) that the universe is 13-14 billion years old.
That's just 1 of 100 counterpoints to expansion.
Example -- SB satori woofers/drivers measure the best.
Many people don't like them because they are not detailed or slow or some other reasons.
I like them, but I'm not a real audiophile.
They are slow woofers that go deep.
Look at CSD or pulse/step response.
But with tweeters the CSD/step don't seem to tell you how they will sound too much maybe.
No matter how much you know, the amount of information you don't know is always infinite.
Tests are there to tell you how something might perform, not how something will perform.
Also you're dealing with psychoacoustics, that's a real word? Wow. Thought I made it up.
That's why I bought the best 2-ways made by Joe D. a few years back and I liked the sound of Bose 301's better.
Usher 8948a and 9950.
Joe D.: "let me measure them for you". My reply: "No, thank you."
The possibility that Bose isn't all just marketing is less than 0%, just like with everything.
There isn't much information in the 2-4 KHz plus range.
I do like blind A/B testing the best though.
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Woh some guy did this:
https://www.diyaudio.com/community/threads/experiments-with-grs-pt6825-8-box-volume.386368/
Guess that answers a lot of questions about the volume options regarding the grs-pt6825-8, at least.
https://www.diyaudio.com/community/threads/experiments-with-grs-pt6825-8-box-volume.386368/
Guess that answers a lot of questions about the volume options regarding the grs-pt6825-8, at least.
No real surprises there………this driver is good from 800hz on up where it’s acoustic shelf is best served with an electrical filter overlapp. A mild contour filter for shaping should result in a fairly flat response out to 12k
From the linked thread, the tester appears to have just used it completely open in the back…..that’s a no no for sure……a piece of felt covering the back is essential for the these drivers in an enclosure to attenuate reflections that are out of phase…..even an empty back cup cover would have yielded better results
From the linked thread, the tester appears to have just used it completely open in the back…..that’s a no no for sure……a piece of felt covering the back is essential for the these drivers in an enclosure to attenuate reflections that are out of phase…..even an empty back cup cover would have yielded better results
In the spirit of audiophiledidness, I guess I should add this filter.
I think it's a series notch filter.
What do you humbly-opinionated veil-removing golden-eared graph-oglers think?
That's some nice looking graphs, right?
In the hopes of keeping things simpler, I'm temped to leave the notch out, but it does make the graph(s) nicer and in theory should sound better, no?
I just remembered with this tweeter there's a vertical and horizontal off-axis FR I should try to account for, hmm . . .
I think it's a series notch filter.
What do you humbly-opinionated veil-removing golden-eared graph-oglers think?
That's some nice looking graphs, right?
In the hopes of keeping things simpler, I'm temped to leave the notch out, but it does make the graph(s) nicer and in theory should sound better, no?
I just remembered with this tweeter there's a vertical and horizontal off-axis FR I should try to account for, hmm . . .
