That VC looks crooked and tilted. Also the added on rear basket piece is also crooked compared to the main basket and the gaps between them. If that's what your hard earned cash buys you, then I'd say you're better off with Scanspeak drivers.Just a surround dip, nothing out of the ordinary?
Always happens with a big mismatch in mechanical/acoustical impedance.
Btw, nobody is talking about that the bottom part of the basket is 100% just for looks apparently and doesn't seem to have any function whatsoever? (look at the gap between)
That's also one way to blow your budget up
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Most SB acoustics drivers are incredible value for money. Every once in a while they slip and there are QC issues. The Satori stuff is expected to be better than the regular SB drivers, especially considering the cost. I only had one driver so far with a rubbing VC, which only acted up when it was pushed harder for a while. Madisound sold me the driver and as always took care of it immediately.
In my case it was a 6MW150D. The VC on this driver is pretty stout for a 6" semi-pro driver. The dark color of the VC is a coating they apply to reinforce it and shed heat more efficiently. It looks like a burnt VC but its electrically just fine. The rubbing was from a misalignment and you could only detect it with a low mid sine wave at high level. I went through 40 of these drivers and this was the only bad one I've had so far. What puzzles me is the spec sheet claims it has a demodulation ring at the gap, but I dont see this to be the case. Perhaps they designed the basket to be part of this. I measured 0.37 mH @ 1kHz, which is low for longer 2" windings.
In my case it was a 6MW150D. The VC on this driver is pretty stout for a 6" semi-pro driver. The dark color of the VC is a coating they apply to reinforce it and shed heat more efficiently. It looks like a burnt VC but its electrically just fine. The rubbing was from a misalignment and you could only detect it with a low mid sine wave at high level. I went through 40 of these drivers and this was the only bad one I've had so far. What puzzles me is the spec sheet claims it has a demodulation ring at the gap, but I dont see this to be the case. Perhaps they designed the basket to be part of this. I measured 0.37 mH @ 1kHz, which is low for longer 2" windings.
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I can say by experience that there is not likely to be any damping by the plastic fingers around the motor because they do not come in good contact with it. In fact I have used the fact that there is a small gap between the fingers and the magnet to run nylon monofilament (like fishing line) around the magnet via the gap so that the driver can be supported near the magnet when I hang the driver in my nude dipole loudspeaker that uses it.
Just use REW.
I use an Audio Precision System nowerdays but that's probably not in reach for DIY ;-)
I used ARTA for a university project and found plenty of bugs. Calibration is silly complicated. You could do averages of all sorts of measurements - but not from room acoustic measurements (where you 100% NEED it - like the programmer never used it's own software). And when written to him about the bugs ... the answer was not very ... nice. (But at least some of them got solved in later versions).
The ARTA mesurements don't show the peaks in H3 and H5 like the REW measurements.
I often had inconsistent measurements with ARTA when changing FFT length or sample rates. Hope most of these are solved nowerdays ... but I will not be the one to test it.
I like ARTA. When deep diving into distortion, I use STEPS which is a companion software part of the ARTA suite.
ARTA has the look and feel of the GUI-driven analysis software I used when I was a working engineer. It seems familiar to me. For people used to running Matlab, r, the various Linux home-grown apps that engineers write, ARTA will seem familiar and normal.
ARTA has the look and feel of the GUI-driven analysis software I used when I was a working engineer. It seems familiar to me. For people used to running Matlab, r, the various Linux home-grown apps that engineers write, ARTA will seem familiar and normal.
It's more that I just can't stand the the very convoluted REW interface, I can't stand the always smoothed graph (office excel) looks even less. Unfortunately, both of those seem to be the standard these days in a lot of software programs
Including weird jumping around..... just .... why.....
This seems to be kinda the standard when it comes down to many software programmers for some reason that is unknown to me?
The phenomenon that measurement results change when using different FFT settings should not surprise one I think. Picking right block lengths, useful sampling rates and using the right windowing on both blocks and time window seems an art in itself.
I think both REW and ARTA are valuable contributions and used with the right interfaces and knowledge they make AP pretty obsolete. Because of the price difference of course. There always will be reasons to keep the expensive gear on the bench, even if it only were to show off. Seen that happen in the past and it likely is the same now.
When you change the measurement settings and level changes by a few dB? No - that should not happen. The software needs to correct for that.
But it's long ago I used ARTA, so I hope they solved these issues meanwhile.
Did you work with systems like Audio Precision for a while? You really wanted to go back to a software?
You don't need this when doing some speaker measurements from time to time. But when useing it on a regularly/daily base the gain in speed and confidence pays off.
As I also have to do electrical measurements for projects in an industrial/professional environment there is no question about not useing an AP.
But it's long ago I used ARTA, so I hope they solved these issues meanwhile.
Did you work with systems like Audio Precision for a while? You really wanted to go back to a software?
You don't need this when doing some speaker measurements from time to time. But when useing it on a regularly/daily base the gain in speed and confidence pays off.
As I also have to do electrical measurements for projects in an industrial/professional environment there is no question about not useing an AP.
That totally depends, if the user already is picking a certain combination of let's say a sample rate, FFT size and time window, there will be certain results from that accordingly.
There are no magic tricks there, that is just plain math.
For know I just find the statement way to vague.
So I am curious about the specifics, because I never had such issues myself.
I think it's not even important, but even mandatory that the user at least has some knowledge and understanding of what's under the hood of a certain program.
If not, it's extremely easy to fall into traps when not being careful enough.
5-10 years ago I would have agreed with you on the AP.
These days there are audio devices (like the E1DA COSMOS or Quant Asylum ), for a fraction of the price.
These perform the same/very similar or like 80-90%, while the costs are much much lower.
I have worked with AP as well, and personally I think for most professional audio projects/products it's way overkill and therefor overpriced. When used in a serious lab/science environment, it's a totally different story.
But that is more because the price of such systems are not very significant anymore.
That doesn't mean there are other ways to get the same or better results.
Keep in mind that you mostly pay for convenience.
Member
Joined 2003
FWIW my comparison between ARTA and REW for distortion produced exact same results as long as configuration and signal was also the same. Both have their pros and cons, REW has a cumbersome UI, and phase is not presented from the IR window start, rather it is from t=0 regardless of window setting, which is not what I want for measuring with a timing reference. ARTA on the other hand has an easy UI, but lacks some windowing features such as left window, overlays don't include phase, IR measurement cannot be frequency limited, and LIMP can't do a quick sine sweep measurement. However...cost of either software is low for what they provide so I won't complain too much.
My workflow:
For frequency response measurements is measure with ARTA, process IR through VituixCAD IR-FR tool which is well featured.
For impedance I stick with Limp despite the extra time required for good measurement, it's much easier to use vs REW for this task (personal opinion).
For distortion, I use REW primarily since it can limit the sweep frequency range and even apply any EQ filter to the measurement sweep with the latest version. These features as well as the noise floor determination make it a better solution than ARTA for distortion evaluation. I rarely use STEPS, it's slow and despite the claims I don't find it provides more accurate information than a sine sweep.
My workflow:
For frequency response measurements is measure with ARTA, process IR through VituixCAD IR-FR tool which is well featured.
For impedance I stick with Limp despite the extra time required for good measurement, it's much easier to use vs REW for this task (personal opinion).
For distortion, I use REW primarily since it can limit the sweep frequency range and even apply any EQ filter to the measurement sweep with the latest version. These features as well as the noise floor determination make it a better solution than ARTA for distortion evaluation. I rarely use STEPS, it's slow and despite the claims I don't find it provides more accurate information than a sine sweep.
That is very similar to my workflow as well.
Time window works better in VituixCAD
I have also never really seen any big differences in STEPS, and also from the math point of view I am missing the reasons why actually.
Btw, what are you using the left window feature for?
In most programs this is just rectangular and for our purposes, I don't really see reasons why you want something else for just the left window.
In fact, that window can be basically be with a length zero (or very small).
Member
Joined 2003
For left window, it is to ensure correct output when processing measurements in bulk. For example, if I set the window start by the tweeter on-axis impulse, depending on the speaker, a large waveuide or horn may place tweeter behind the midrange, so processing of midrange impulse will be behind the window start. Left window allows for correct FR in this instance with negative phase.
Other reason is that off-axis response impulse is often slighly behind the on-axis impulse for timing, so left window ensures correct result if window start is placed very close to on-axis impulse.
Left window is not "required", but is a "nice to have" feature to allow flexibilitity in window/phase reference points and provide guarantee of accurate results when processing many measurements with same window start time.
Other reason is that off-axis response impulse is often slighly behind the on-axis impulse for timing, so left window ensures correct result if window start is placed very close to on-axis impulse.
Left window is not "required", but is a "nice to have" feature to allow flexibilitity in window/phase reference points and provide guarantee of accurate results when processing many measurements with same window start time.
