Here comes new impedance measurement markbakk.
I having a hard time to set all the "right" settings in REW (because i never remember them)
Have disturbances in the measuring circuit, but you have to "remove them" in your head when you look at the curve. ( it wasen´t any last year?)
Also get small differances ! ( as you can se in the plot) and peak is 115 hz.
Reference impedance line is a 7,8 ohm resistor.
Brown trace is 10 cm and then 8, 6, 4, 2 and ending at the top (97-99dB) with 1 cm Blue trace 👍
best regards John
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Ok thx. All in all, I think your crossover needs attention. The bass and mid section overlap too much. You can see that some cancellation is going on between 300 and 500Hz. The mid to high crossover could be finetuned, as a (modest) peak at around 3k generally has to be avoided.
Furthermore, although some of the measurements of the mid have some resemblance, others divert and show more or less the same issue. I can’t explain the differences. But the BSC in the mid crossover possibly isn’t adequate.
Furthermore, although some of the measurements of the mid have some resemblance, others divert and show more or less the same issue. I can’t explain the differences. But the BSC in the mid crossover possibly isn’t adequate.
In your Vituixcad info the power and directivity does show that there is some excess energy in the 3Khz region, so that is definitely something you could go over and verify that the transition to the tweeter is maybe better than that old ? data set.
In terms of getting higher than 1 metre to avoid room bounce as they are separate enclosures it should be relatively simple to use a piece of household furniture or some old loudspeaker stands and some books to get them high enough to get a decent 1m or 2 metre reading on axis and maybe some 30 or 45 degree of axis so that you can see that they drop of smoothly. However, if you like the sound maybe leave well alone until you are feeling better.
Interestingly the Xover for all three units is positive phase, and looking at the derived phase they are not closely aligned. To satisfy this question what does the phase look like if you flip the midrange phase does the phase measurements for the bass-mid or mid tweeter become better aligned ?
If so, a bit of subtle tuning of a component in either high pass or low pass may be beneficial, keeping in mind you should be aiming for a smooth gradual taper downwards at the the high frequencies.
However as you listen maybe a bit further away you may not want to much attenuation. If the traces don't happen to look more aligned within one or two mouse clicks, i would be tempted to leave it alone and restore your original values and midrange phase and just work around the mid tweeter transition.
Take it easy. 🙂
In terms of getting higher than 1 metre to avoid room bounce as they are separate enclosures it should be relatively simple to use a piece of household furniture or some old loudspeaker stands and some books to get them high enough to get a decent 1m or 2 metre reading on axis and maybe some 30 or 45 degree of axis so that you can see that they drop of smoothly. However, if you like the sound maybe leave well alone until you are feeling better.
Interestingly the Xover for all three units is positive phase, and looking at the derived phase they are not closely aligned. To satisfy this question what does the phase look like if you flip the midrange phase does the phase measurements for the bass-mid or mid tweeter become better aligned ?
If so, a bit of subtle tuning of a component in either high pass or low pass may be beneficial, keeping in mind you should be aiming for a smooth gradual taper downwards at the the high frequencies.
However as you listen maybe a bit further away you may not want to much attenuation. If the traces don't happen to look more aligned within one or two mouse clicks, i would be tempted to leave it alone and restore your original values and midrange phase and just work around the mid tweeter transition.
Take it easy. 🙂
Yes you are right, but it´s a harder "true" thing in reallety, Vituaxcad don´t show the "xover-struggle" i had with the 130-400 hz area.
And the 300-500 cancellation don´t show up in the measuremts.
Yes, that was my gole when i started this thread 👍
But i can´t se it in most measuremts over 2 meters strange enough?
?. means what?
And i have try a little different xover solutions, and some is better with small margins (but with expensive components, like a 7,5 mH coil)
Here is one other xover solution, but more expensive.
And unother LR2 with litte lower impedance.
regards John
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Yes Ray it can be better "above all in Vituaxcad" with more component, but not so much in reallyty. (difficult to balance more cash or not)
Absolutly Ray!
Thats on my list!
I have aslo wonder about that!
I think it´s so strange....
And tryed before to shift phase on the woofer, but no improvements at woofer-midrange meeting, but must test again! (also midrange)
👍 thanks for idea´s Ray 🙂
Best regards John
Please forgive me for going off topic here for a moment to address an important issue I'm rather passionate about. I'd like to give you some encouraging words with your situation, coming from someone in a similar situation...
The pain medication itself you're taking isn't really an issue here, ie. what it can or will potentially "do to people". The potential for addiction to opiates is mainly there if the person taking them has an addictive personality, history of certain mental issues (depression, anxiety) and takes them for reasons other than just pain relief itself. If you're taking the medication in increasingly higher and more frequent doses, attempting to feel numb, warm and fuzzy, then there's definitely a problem.
If you're taking it for pain in a responsible manner and according to the doctor's instructions, there is very little if any concern for becoming addicted. You may acclimate to it gradually over time, possibly needing a slightly higher dose for the same efficacy, but that doesn't mean you're becoming addicted to it. That's the critical difference between dependency and addiction.
Unfortunately there's a huge stigma and vilification that comes with prescription opiates. A lot of people don't understand the need and role of this medication, assuming people who take it are by default lower class and lacking in character, automatically being doomed to becoming an addict or already being one. We can partially thank the media for spreading this misinformation, among other people up top and in charge.
The honest truth is the medication can and usually will significantly improve the quality of life in people with severe, chronic pain if its administered properly, even under long term use. Don't be too worried about taking some medication if you really need to. Thats what its there for. It sounds like you have a healthy respect for it and approach it accordingly.
Its very sad people quickly pass judgment onto others who take opiate pain meds, assuming they abuse them being they're opiates and vilify them, automatically linking to the use of other hard drugs. Even pharmacists are now doing this. They should be working with the patient, finding solutions and helping them, not passing judgment and treating them like bad people who just want a fix.
I hope this helps a little and gives you some piece of mind, not to be too concerned with taking medication if you genuinely need it. Sorry for being so personal about this, but I hate to see other human beings suffer needlessly if they have options.
One thing to be aware of if taking something like Vicodin is its inclusion of acetaminophen, which can be harder on your system than the opiate at some doses. Had a doctor tell me once to take them basically every 2 hours if needed for the day after a procedure - took a couple months for my liver enzymes to get back to normal.
Sims in post #104 obviously are using actual measurements. Obviously they are not dual channel. Does the sim use measured impedance of drivers too?
So, you should give driver location parameters too for VCAD2.
You are using passive components - coils, inductors and resistors, but in VCAD it is possible to use IIR parameters too, they are immune to impedance changes and impedance ot T/S data is not needed. By giving target response, VCAD can suggest FIR or IIR settings.
(I don't use VCAD for design myself, so I can't give detailed instructions)
So, you should give driver location parameters too for VCAD2.
You are using passive components - coils, inductors and resistors, but in VCAD it is possible to use IIR parameters too, they are immune to impedance changes and impedance ot T/S data is not needed. By giving target response, VCAD can suggest FIR or IIR settings.
(I don't use VCAD for design myself, so I can't give detailed instructions)
That region indeed isn’t so simple. Plus you always end up with expensive components. There’s a reason people stay away from designing passive three way systems.
BSC = baffle step correction. Needed for correcting the acoustic effects from 4π to 2π radiation transition of a given loudspeaker in a given baffle/enclosure.
You are so welcome profiguy 🙂
And you are right of course!
Have large respect for all opiates and benzodiazepines, both of them "will ruin your whole life" if you do not have strong morals and take responsibility for yourself, because unfortunately the doctors who prescribe the preparations do not take any responsibility themselves.
I have quickly realized that you need to rase/dubble the dose after only a week if you take it regularly, and i don´t "accept" that.
So im trying to cope (and listen on my body, so tried to rest when i need) in the weeks and take "weak doses=5-10 mg" friday and saturday.
Have done so 10 years now, and it still works
Had also under long period try out with complement of 40 mg Saroten/tricyclic/day or Gabapentin 900 mg/day + 100 mg setraline.
So now use 900 mg Gabapentin and Setraline 100 mg daily, 5-10 mg Oxy in the weekends and 7,5 mg Zolpidem 1-3 times a week when i can´t sleep.
Trust the doctor´s first few years, but all meds in and out made me also get more mental health issues like depression and even panic attacks (incredibly unpleasant & made everything worse).
So after some time i decide to read alot, and get some good knowlege about the actual medecin involved.
Still don´t have "come back" to my old self, and probably never will.
Becouse when "the closed door´s" in you brain had been opend, you can´t close them again! (hard to explain, but my type of medecin "creates that")
Will soon come back with speaker-diy-things, and wish you all a nice weekend!
best regards John
Right mattstat, more then 3,5-4 g acetaminophen daily can "in a minute" suddenly destroy your liver!
And liver´s, lungs etc have a very long healing time, and usually does not return to 100% function.
Hope you are fine now!
regards John
Hello there finnish neighbor 🙂
Had done so many simulations and measurements, so my brain are not sure ( in every detail).
But have now done 3 new different simulations WITH measured value on tweeter and midrange (both spl and imp)
BUT these don´t have measured woofer values (because I think it is difficult for spl to compensate own near-field measurements)
So the woofer have manufacturer's spec on spl & imp curves!
A little different in numbers of components and HP or LP first on midrange & a little impedance differences are what I can discern, but you talented people can probably see a lot more & tell me which of the filters is more beneficial.
Best regards John
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Yes mattbakk, its hard to measure that region properly and also the $ ´quickly flys away
I don't hesitate for a second, to try designing passive 2/3/4 or 5 way´s, or 3½/4½.
Failures provide lessons, and many lessons give you knowlege.
Learn from books & text or in real life with practical training depend on person, me can´t learn with books since 25 years back, but practical training works 🙂
I don´t "like" aktive filters for midrange and tweeters, and i always strive to get drivers to have their own "natural" little coloration on the sound.
So cd to preamp to amp is my "melody", and also if using a receiver to always use "Pure direct".
In that way i also "learn more and get more experience" and really can distinguish between the different components' own characteristics as far as the sound is concerned.
regards John
Possibly in terms of knowing you like to listen at higher volumes the first option rolls of the tweeter the fastest which should stop it from being stressed. The on axis response looks good to me and the off axis levels hopefully decline smoothly and maybe the 500Hz wiggle isn't there at 30 or 45 degrees of axis.
The 500 Hz dip aligns with the woofer phase change shown in green, maybe scroll down in level in the first window when you are in VituixCad and see how the woofer response dies away below 75dB. If there is a bump or step that down at 70dB that may explain the wiggle ?
Impedance and phase do look OK, although below 50 Hz it will take current. At 50Hz the overall impedance is around 3ohm at -45 degree phase. Fortunately a lot of recorded music tends to be tailing off in this frequency area , although there are exceptions, and I guess we all have a few examples in our music collection. At 400Hz the impedance is also 3ohms approx. but almost zero phase which will be fine for lots of amps.
The second crossover maybe a little better from a impedance viewpoint, and it has a flatter response than 1, although the flatter response means very little in the scheme of things.
Interestingly which one did you prefer sound wise? Is one nicer to listen too at low or high level. which one ticks the most boxes for you?
The third one highlights how much care is needed with building a three way with individual boxes for each driver, judicious placement in the differing X, Y and Z planes maybe would smooth out the dip to the point that it would be not noticeable to many people, and would only show up in the measured response.
As a caveat I have never designed or made a three way and if we could instantly pop over to your listening space we would probably still be discussing what we actually hear for many hours.
Happy listening.
The 500 Hz dip aligns with the woofer phase change shown in green, maybe scroll down in level in the first window when you are in VituixCad and see how the woofer response dies away below 75dB. If there is a bump or step that down at 70dB that may explain the wiggle ?
Impedance and phase do look OK, although below 50 Hz it will take current. At 50Hz the overall impedance is around 3ohm at -45 degree phase. Fortunately a lot of recorded music tends to be tailing off in this frequency area , although there are exceptions, and I guess we all have a few examples in our music collection. At 400Hz the impedance is also 3ohms approx. but almost zero phase which will be fine for lots of amps.
The second crossover maybe a little better from a impedance viewpoint, and it has a flatter response than 1, although the flatter response means very little in the scheme of things.
Interestingly which one did you prefer sound wise? Is one nicer to listen too at low or high level. which one ticks the most boxes for you?
The third one highlights how much care is needed with building a three way with individual boxes for each driver, judicious placement in the differing X, Y and Z planes maybe would smooth out the dip to the point that it would be not noticeable to many people, and would only show up in the measured response.
As a caveat I have never designed or made a three way and if we could instantly pop over to your listening space we would probably still be discussing what we actually hear for many hours.
Happy listening.
Both first two crossovers have an ugly dip down to 2Ω in the low midrange. I wouldn’t do that, much music energy is in that frequency region.
Hi John
I simulated your project in VituixCad2 guessing the sizes and coordinates of the drivers on baffle from the images you posted.
Find attached a folder with the main project, the baffle step/diffraction and merging projects. The woofer Vb is 66L tuned at 25Hz while the mid is a closed box of 4L. I used traced curves to simulate the x-over.
Hope this helps
Regards
Saverio
I simulated your project in VituixCad2 guessing the sizes and coordinates of the drivers on baffle from the images you posted.
Find attached a folder with the main project, the baffle step/diffraction and merging projects. The woofer Vb is 66L tuned at 25Hz while the mid is a closed box of 4L. I used traced curves to simulate the x-over.
Hope this helps
Regards
Saverio
Yes i maby must think on that with my listeninglevels Ray, did¨t before you drew attention to it.
Think the 400 hz wiggle is an artifact because further away it does not exist, and a little toe-in I usually does.
Mean this ? (see pic)
Used manufactor specs imp and SPL on the Dayton 390ho, so not measured from me!
Will also try to get a little better impedance at the lowest "areas", but hard when working with 4 ohm woofer and 4 ohm midbass/midrange and 6 ohm tweeter.
My xover-parts ( especially caps ) are entirely finish from 36 uf and down, so i haven´t had the possibillity to listen on more then 1 or 2 xover¨s.
And after 2-300 soldering on/off the components arent exactly "nice" to work with hahaha.
Your are completely right Ray, every movement of the mid and tweeter-boxes make slightly different measurements.
And I can use that if I want in a possetive way, but my original design was ment to be "thin" like in woofer playing sideways with the side facing the listener, and mid/twe on topp.
Like the pic but woofer-port backwards.
hahaha, yes we would 😍
regards John
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Yes but its real hard to get real "good" impedance with these 4 ohm woofer and 4 ohm midbass/midrange and 6 ohm tweeter.
I will try to reach 3 ohm and accept one 2,7-2,8 ohm dipp.
And even if I have 2 ohm stabile amp, I want to "make the best of it", so even receiver can be used.
Do you have any suggestions for me ?
And you can have my FRD and ZMA files if you have ti,e to simulate a little.
Regards john
You´r so kind Saverio aka shadowplay62 🙂
Sadly i haven´s lear how to get the files into Vituaxcad, and my head is not what it used to be with these medications.
From time to time my head "work´s better", and that time i can be more productive 👍
My original design was ment to be "thin" like in woofer playing sideways with the side facing the listener, and mid/twe on topp.
But no doors are closed regarding woffer playing sideway´s or forward.
Woofer have 113 liters box ( before port/driver and 2 reinforcements )
So around 100 liter netto.
I downloaded you´r folder, but don´t know how to use it.
Best regards john
Hi Jawen,
With the file that Shadowplay62 kindly produced for you. Using windows explorer move the file or copy it into the VituixCad folder. Then you should be able to open VituixCad , select open file and select the jawen.vxd file or the only .vxd file in that folder, and open that, the information should load from there.
Have fun.
With the file that Shadowplay62 kindly produced for you. Using windows explorer move the file or copy it into the VituixCad folder. Then you should be able to open VituixCad , select open file and select the jawen.vxd file or the only .vxd file in that folder, and open that, the information should load from there.
Have fun.