A good tweeter to match 5" SB Acoustics Magnesium Woofers

[xmax]

I imagine the 4K dip is related to edge diffraction the baffle differs from the design a little I have not got around
to cncing a exact baffle. I'm extra busy and just getting over the damn flu. But again I don't think it will make enough difference
to change my mind.

Correct Solid is the 2nd harmonic and dotted is 3rd.

[dlr]

I imagine the 4K dip is related to edge diffraction the baffle differs from the design a little I have not got around
to cncing a exact baffle. I'm extra busy and just getting over the damn flu. But again I don't think it will make enough difference
to change my mind.

Correct Solid is the 2nd harmonic and dotted is 3rd.

I'm not trying to change your mind. I'm interested in the measurements and interpretation. The dip is 5K, not 4K, my mistake on that, but I don't see how a 2nd order distortion dip such as that can be diffraction related. It's in the 2nd order harmonics, there's a dip at 2K. 5K is not a 2nd order harmonic. It's not 3rd, either. In fact, not a harmonic of any kind to the dip centered at 2K.

You've also not answered the question of the time window used. The graph has no indication of any sort of time limitation, the response shown goes down to 10Hz which wouldn't even be possible in essentially any anechoic chamber extant that I've read about given even their limitations. Everything below about 400Hz looks to be in noise, not useful, the two arrows at 150 and 300 provide focus on anomalies that look also to be of no use, the 5K dip in 2nd harmonic is odd as I would expect it to be at 4K (again, maybe I'm interpreting it wrong), all of which makes me question the distortion results overall.

How can the 5K be a 2nd harmonic of the diffraction at 2K? Why does 3rd harmonic in the response with the resistor increase below 3K when the drive signal level is down, yet decrease above it? Provide more detail, it could help answer questions. I suspect I'm not the only one with those questions.

And again, what was the time window used? What kind of time window was used? Certainly you know those. That will have a significant impact on any measurements.

dlr

[dcibel]

Yes I do know a thing or 2 about noise, let's say there is noise in the system why is it louder with the resistor?

You're asking what a source of noise could be? The list is pretty long, furnace, ac, fridge, amp hum, or even a recording engineer that can't keep his yap shut can all be sources of noise during a measurement. It is important to keep everything very quiet through the duration of the measurement for distortion, for good reason as you can see the harmonic information is often very close to the noise floor of the equipment.

[xmax]

I'm not trying to change your mind. I'm interested in the measurements and interpretation. The dip is 5K, not 4K, my mistake on that, but I don't see how a 2nd order distortion dip such as that can be diffraction related. It's in the 2nd order harmonics, there's a dip at 2K. 5K is not a 2nd order harmonic. It's not 3rd, either. In fact, not a harmonic of any kind to the dip centered at 2K.

You've also not answered the question of the time window used. The graph has no indication of any sort of time limitation, the response shown goes down to 10Hz which wouldn't even be possible in essentially any anechoic chamber extant that I've read about given even their limitations. Everything below about 400Hz looks to be in noise, not useful, the two arrows at 150 and 300 provide focus on anomalies that look also to be of no use, the 5K dip in 2nd harmonic is odd as I would expect it to be at 4K (again, maybe I'm interpreting it wrong), all of which makes me question the distortion results overall.

How can the 5K be a 2nd harmonic of the diffraction at 2K? Why does 3rd harmonic in the response with the resistor increase below 3K when the drive signal level is down, yet decrease above it? Provide more detail, it could help answer questions. I suspect I'm not the only one with those questions.

And again, what was the time window used? What kind of time window was used? Certainly you know those. That will have a significant impact on any measurements.

dlr

"Why does 3rd harmonic in the response with the resistor increase below 3K when the drive signal level is down, yet decrease above it?"

Because of the transfer function allows more low frequency information through because the 6.2 ohm resistor essentially changes the
the tuning frequency of the filter lower, a simple analogy would be using a filter for a 8 ohm tweeter designed for a 4 ohm tweeter.
I have came to this conclusion from experience.

The info below 500hz is interesting at best, at this point I will test everything again with the exact baffle and non-102 degree fever.
I also invite people to do some testing on their own, frankly I was taken by they amount of people not seeing what I am talking about.

[dlr]

"Why does 3rd harmonic in the response with the resistor increase below 3K when the drive signal level is down, yet decrease above it?"

Because of the transfer function allows more low frequency information through because the 6.2 ohm resistor essentially changes the
the tuning frequency of the filter lower, a simple analogy would be using a filter for a 8 ohm tweeter designed for a 4 ohm tweeter.
I have came to this conclusion from experience..

Still no answer on the window/gate.

In your example, the filter Fc increases (can't say precisely what point you considered to be Fc) as I see it, the level at 3K is practically unchanged, the response below it is down relative to 3K, almost -6db all the way to noise, so how is that lowering the tuning? The level above 3K is commendably flat with the resistor.

dlr

[xmax]

Still no answer on the window/gate.

In your example, the filter Fc increases (can't say precisely what point you considered to be Fc) as I see it, the level at 3K is practically unchanged, the response below it is down relative to 3K, almost -6db all the way to noise, so how is that lowering the tuning? The level above 3K is commendably flat with the resistor.

dlr

To be perfectly honest I'm not sure how to tweak the gate settings on the software, I remember when I first got it, I talked to the designer ,
he went over a few guidelines with me about keeping reflections out of the equation and I have been using it ever since with great success.

I will be happy to retest it with whatever conditions you like. I also encourage others to do the exact same test to see what they get. If nothing
else, all this bickering has got people thinking about the concept and when it can be used successfully.

Last but not least I encourage people to run a test like this and just listen to the tweeter with and without a post filter resistor of 6.2 ohms
with the tweeter volume corrected if needed. I'm pretty sure most anybody will hear what I am saying.

[ryanbouma]

Xmax, it is great that you admit you dont know how to tweak the gate time. Shows maybe you're not as arrogant as you have appeared to be. But to be perfectly fair and honest, if you don't know how to do that, you don't know how to measure a speaker. The gate/window time is pretty much the single most important setup issue with any speaker measurement. IMO its more important that drive voltage, microphone type, software type, amplifier, etc. The only thing more important would be getting the distance from reflections as far as possible and mic distance. Which those things actually dictate the gate time, which is why they are more important. I am with the others that disagree with you about how a resistor makes distortion rise and such. At this point it is clear you have not proven anything despite the comparison graph you posted, which was not very helpful even before we knew it was possibly not reflection free. Sent from my SGH-I337M using Tapatalk

[xmax]

Again I understand the importance of the gate setting but I have not had to change it. I will redo the
test to minimize the chance of reflections skewing the test I will also use REW if you prefer and set the
gate and mic distance how ever you like. (I imagine the mic fairly close and all other surfaces as far away as
possible)

Although since any reflections skewing the first test would be the same with and without the resistor,
I believe the 3rd harmonic distortion will be highish regardless of whoever does the test with any reasonable
gate/mic ratios.

[xmax]

As you can see the third harmonic is higher at 3K (the most sensitive area of our hearing)
with the resistor only the B&K mic has low enough distortion to see that. If you look
at the Via wave you can see the how low I like the 3rd harmonic. The test conditions should not have
anyone concerned about reflections. The other 2 mics are the UMM-6 and the
USB OMNI.



Maybe you guys measure speakers for different reasons than I do.
Although looking at it again the third harmonic is so low I don't think it's an issue.
I will return to this test at another date in the mean time think for yourselves and please don't drink the kool-aid.

[Kornbread]

Could you show us what the impulse response looked like?

[Waboo]

Anyone know when the 6" versions will show up? Madisound has been showing the 5" and 8" on their site for maybe a month now, but not the 6".

Looks like they just showed up today on the Madisound site, in both 4 and 8 ohm.

[xmax]

Looks like they just showed up today on the Madisound site, in both 4 and 8 ohm.

Nice!

[Waboo]

I was thinking maybe they're a pretty nice and reasonably priced midbass without stepping up to the Satori. I've been away from speaker building for quite a few years now and this new line has just kinda caught my eye. I don't know, maybe it's the white cone.

[xmax]

I have used the carbon fiber cone versions built on the same platform and they are incredible!
These seem every bit as good if not better. I will have some soon. Too bad I don't know how to measure
speakers...

[xmax]

Xmax, it is great that you admit you dont know how to tweak the gate time. Shows maybe you're not as arrogant as you have appeared to be. But to be perfectly fair and honest, if you don't know how to do that, you don't know how to measure a speaker. The gate/window time is pretty much the single most important setup issue with any speaker measurement. IMO its more important that drive voltage, microphone type, software type, amplifier, etc. The only thing more important would be getting the distance from reflections as far as possible and mic distance. Which those things actually dictate the gate time, which is why they are more important. I am with the others that disagree with you about how a resistor makes distortion rise and such. At this point it is clear you have not proven anything despite the comparison graph you posted, which was not very helpful even before we knew it was possibly not reflection free. Sent from my SGH-I337M using Tapatalk

You are 100% right, I was wrong, you guys should go about your buisness. If I ever have time to prove to you what I hear from this
type of filter/pad I will let you know. In the mean time please keep crossing tweeters over so close to the Fs not mindful of the transfer function.

Anybody interested in my findings with the Viawave etc, you know how to find me.