The Audax PR170N0 6.5" is used in the Peavey SP3 and Peavey SP3G speakers with the 15” BWX/KADT Black Widow.
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The Audax PR170N0 6.5" is used in the Peavey SP3 and Peavey SP3G speakers with the 15” BWX/KADT Black Widow.
Nice find. They tune it to 58 Hz, which produces a nice flat response and sharp knee in my model.
Hi,
Yes. Maximum power for linear excursion is around 40W. A 98dB/2.83V/1m Speaker makes a heck of a racket with that.
It is my understanding that the OP wants a home LOUDSPEAKER, but not a bona-fide PA Systems.
Also, exceeding X-Max simply means more distortion. At frequencies that low the human ear is remarkably tolerant and high volumes decrease our sensitivity to distortion too.
I remember at many gigs our light show man, complained I was over-driving the PA system (well, I was just at the edge) with earplugs that knocked 20dB or so of the SPL that was clearly audible (we both wore them), with them out the overload magically disappeared... ;-)
2.6mm actually. And I suspect the whole thing will handle +/-10mm without damage, it will just distort/compress.
The frequency is set very low. It behaves actually like a sealed box. I usually do that, so I can see if there is mileage in venting... Often there is. TBH I find not sealing boxes seems to sound less compressed, more alive.
150 Liter Box, tuned to 40Hz.
For much music this is a good compromise. The lowest E on a normal e-Bass is around there.
Okay, a Subwoofer is needed for 32' Organ pipes and 5 or 6 String E-Bass (and syth bass), but for most music it works fine.
Using this slightly falling bass response tends to tighten up the Bass to something more akin to sealed systems, but with more LF extension and LF powerhandling.
???? Where?
Ciao T
Yes. Maximum power for linear excursion is around 40W. A 98dB/2.83V/1m Speaker makes a heck of a racket with that.
It is my understanding that the OP wants a home LOUDSPEAKER, but not a bona-fide PA Systems.
Also, exceeding X-Max simply means more distortion. At frequencies that low the human ear is remarkably tolerant and high volumes decrease our sensitivity to distortion too.
I remember at many gigs our light show man, complained I was over-driving the PA system (well, I was just at the edge) with earplugs that knocked 20dB or so of the SPL that was clearly audible (we both wore them), with them out the overload magically disappeared... ;-)
2.6mm actually. And I suspect the whole thing will handle +/-10mm without damage, it will just distort/compress.
The frequency is set very low. It behaves actually like a sealed box. I usually do that, so I can see if there is mileage in venting... Often there is. TBH I find not sealing boxes seems to sound less compressed, more alive.
150 Liter Box, tuned to 40Hz.
For much music this is a good compromise. The lowest E on a normal e-Bass is around there.
Okay, a Subwoofer is needed for 32' Organ pipes and 5 or 6 String E-Bass (and syth bass), but for most music it works fine.
Using this slightly falling bass response tends to tighten up the Bass to something more akin to sealed systems, but with more LF extension and LF powerhandling.
???? Where?
Ciao T
2.6mm ?
You are right! I checked the BB Pro parameters and it was 2.6.
If you have 10 mm Xmech, then you are good to 20 Hz at 100 Watts on any vented alignment.
However, he really needs a sub (which I think he already has), so if he uses vented I would recommend using the box frequency Peavey uses and set it at 58 Hz. F3 will be 59.5 Hz. For that alignment:
Box is 3.5 cubic feet
vents would be two 4" diameter and 1.23" long each.
You could go larger, but at that frequency port compression is probably not going to rear it ugly head (peaks at 12 m/s @ 100 W).
Personally, I would try to make a 2-way out of this system to reduce complexity and cost.
So, to be able to do some calculations on the money side while waiting for some responde form Peavey, if I go with a 2 Way, besides the speaker ( $ 120 ), I will have to do 1 crossover for the ~1.5 KHz area, the box will need a lot of fill inside right? and would that be it?
Also in the other case, the 3 Way, I will have to buy the 2 speakers ( $122 ) plus 2 crossovers and maybe a little fill or none is fine?. Since now the speakers will have a dB level that matches better, will the active crossover still be needed and therefore bi-amping be needed as well ?
Is there anything else that will be needed for any of the 2 cases? ( besides extras like maybe handles or legs or any other normal construction parts of course )
Leo
Also in the other case, the 3 Way, I will have to buy the 2 speakers ( $122 ) plus 2 crossovers and maybe a little fill or none is fine?. Since now the speakers will have a dB level that matches better, will the active crossover still be needed and therefore bi-amping be needed as well ?
Is there anything else that will be needed for any of the 2 cases? ( besides extras like maybe handles or legs or any other normal construction parts of course )
Leo
If you use an active crossover, you won't need a passive crossover and visa-versa.
However, the active route requires an active electronic crossover and an amp for each speaker.
There are always little things you need to complete the project such as connectors, wires, etc.
Between the three different designs the relative costs would fall in this order from most expensive to least:
Active 3-way system
Active 2-Way system
Passive 3-Way System
Passive 2-Way System
Headphones
The active system is the most flexible and best sounding system. You need an active crossover such as Behringer's DCX2496 for $300 and then you need more amps. Every speaker gets connected to its own channel of an amp.
Passive systems are cheaper, but you can't adjust them without physically replacing components. Passive systems must be designed well or they will not sound good. The best passive system will never sound as good as a good active system when set up correctly.
These are just some of the things you need to know to understand what direction to go. Keep asking questions, that's the only way to really understand all this.
Ja Ja! I love the Headphones option
OK, so I would love to go the route of the Active crossover but for the time being I dont have the money for it, even though I will in the future.
So I know that for passive crossovers it is much better to do some custom ones for this system and I will if the price permits me now.
Now a question just to understand things better, if for example the crossover I need is a 400 Hz 2nd Order 12dB one, and there is one like that that is sold somewhere, why is it that is better to build it yourself. Is it the quality of the components? Or some other parameters that I don't know of?
Also, I want to go for now with the passive crossover route but I may not have the money to build them yet ( I dont know exactly how much will they cost ) what if for the moment until I save enough money, I get some off the shelf ones as a stop gap like someone said before and as soon as I can make the good ones I do the swap? Will the system sound so bad or could be ok to pass the time?
Thanks for the help.
Leo
OK, so I would love to go the route of the Active crossover but for the time being I dont have the money for it, even though I will in the future.
So I know that for passive crossovers it is much better to do some custom ones for this system and I will if the price permits me now.
Now a question just to understand things better, if for example the crossover I need is a 400 Hz 2nd Order 12dB one, and there is one like that that is sold somewhere, why is it that is better to build it yourself. Is it the quality of the components? Or some other parameters that I don't know of?
Also, I want to go for now with the passive crossover route but I may not have the money to build them yet ( I dont know exactly how much will they cost ) what if for the moment until I save enough money, I get some off the shelf ones as a stop gap like someone said before and as soon as I can make the good ones I do the swap? Will the system sound so bad or could be ok to pass the time?
Thanks for the help.
Leo
You are 100% theoretically right, but in this case I think there are good reasons why that will not be the case.
I recommend as simple a 2-way as possible. First, he can't measure the T/S parameters nor the actual frequency responses.
Without that there is little sense in pouring money into a crossover that is only a best guess.
Keep it simple, keep the cost down, and you will have a great starter system that he can upgrade over time without breaking the bank.
Hi,
Okay, the issue is electrical slopes vs. acoustic slopes.
All of the shelf crossovers omit such niceties as impedance equalisation (necessary to avoid nasty peaks in the crossover region) and of course they are "textbook" designs.
That means they work well with "textbook" drivers (that is drivers with a resistive impedance and a flat frequency response from DC to light).
Of course real drivers are very different.
So when combining real drivers with non-flat frequency response and reactive impedances with such "textbook" off the shelf crossovers an acoustic Disaster is generally unavoidable.
So you must adapt as much as possible the crossover to the drivers.
With Audax PR170M0 and Fostex FT17H the budget is suurvivable and the hard work on the crossover inbetween has been done and documented by others here and on Audio Asylum.
The lower the crossover order and the crossover frequency the greater the chance that the "off the shelf" crossover actually results in a usable system.
So you could try a "shelf bought" 250Hz/2nd order crossover, this may JUST ABOUT work out. Make sure the crossover uses air core inductors and film capacitors. Once you see what a proper crossover using these costs you may reconsider doing your own.
My experience is that the best crossover is no crossver and the secondbest is a tie between first order and "as steep as possible" (10th order is something I have used before) WHICH RE-INTEGRATE a step waveform with minimal ringing.
All the stuff in between, including acoustic 4th order LR slopes sounds bad in some areas. Trust me, been there, done that and got the T-Shirt.
So I would suggest you go with a Zobel for impedance correction on the Peavey Woofer (can be worked out from the published Data) and a single inductor in front of the Woofer, designed for a cutoff of around 300Hz (not 400, you need to "EQ" the woofer a little) with the woofer in reverse polarity.
For the Audax you ideally would use aperiodic damped vents (read a lot of small holes and some felt) to maximally reduce the magnitude of the impedance peak and then just give a capacitor more or less based on textbook calculations for 400Hz. You may need to use a bipolar electrolytic capacitor there, but I would suggest trying to stick to film capacitors, even cheap ones.
This will very likely give a sufficient integration between both drivers.
For the top-end you can start running the Audax without lowpass (or maybe using a series inductor of around 0.1..0.22mH) and operate the Fostex FT17H with just a capacitor in series (around 2.2uF - try a few different values, maybe just buy 1uF X 4 and 0.47uF X 4 and try until it sounds (and maybe measures) right.
Such a system will not be the last word in smoothness and power handling, but it will sound reasonably balanced and even handed, while being very 'direct', 'immediate' and quite exciting sounding. And I think you can actually achieve it. Layer you can upgrade to an active system.
The Audax & Fostex Drivers are both found in some very high priced and well regarded speakers (both Studio & HiFi) and I do not think they will need upgrading, the Peavey BW's you need to keep as long as you your GF, so once you feel the need to improve these speakers you can mess with the crossovers at modest cost or go fully active in steps at greater cost.
Or maybe the speakers will sound just dandy to you and you prefer instead to build a nice tube amplifier kit to drive these speakers...
Anyway, that would be my advise, but you do not have to take it...
Ciao T
PS, I recently designed a speaker that used a 60Hz 1st order crossover. My first very rough cut was just a "textbook" 1st order as described - RC in parallel to the woofer - values calculated from the datasheet, L & C based textbook formula. It sounded and measured much better than one should think.
The finally "fine-tuned" version ended up with some minor value tweaks and the addition of an LCR "trap" to pull down the first breakup resonance of the cone driver, but sonically there was very little to choose between the versions. The final measures notably flatter though...
Okay, the issue is electrical slopes vs. acoustic slopes.
All of the shelf crossovers omit such niceties as impedance equalisation (necessary to avoid nasty peaks in the crossover region) and of course they are "textbook" designs.
That means they work well with "textbook" drivers (that is drivers with a resistive impedance and a flat frequency response from DC to light).
Of course real drivers are very different.
So when combining real drivers with non-flat frequency response and reactive impedances with such "textbook" off the shelf crossovers an acoustic Disaster is generally unavoidable.
So you must adapt as much as possible the crossover to the drivers.
With Audax PR170M0 and Fostex FT17H the budget is suurvivable and the hard work on the crossover inbetween has been done and documented by others here and on Audio Asylum.
The lower the crossover order and the crossover frequency the greater the chance that the "off the shelf" crossover actually results in a usable system.
So you could try a "shelf bought" 250Hz/2nd order crossover, this may JUST ABOUT work out. Make sure the crossover uses air core inductors and film capacitors. Once you see what a proper crossover using these costs you may reconsider doing your own.
My experience is that the best crossover is no crossver and the secondbest is a tie between first order and "as steep as possible" (10th order is something I have used before) WHICH RE-INTEGRATE a step waveform with minimal ringing.
All the stuff in between, including acoustic 4th order LR slopes sounds bad in some areas. Trust me, been there, done that and got the T-Shirt.
So I would suggest you go with a Zobel for impedance correction on the Peavey Woofer (can be worked out from the published Data) and a single inductor in front of the Woofer, designed for a cutoff of around 300Hz (not 400, you need to "EQ" the woofer a little) with the woofer in reverse polarity.
For the Audax you ideally would use aperiodic damped vents (read a lot of small holes and some felt) to maximally reduce the magnitude of the impedance peak and then just give a capacitor more or less based on textbook calculations for 400Hz. You may need to use a bipolar electrolytic capacitor there, but I would suggest trying to stick to film capacitors, even cheap ones.
This will very likely give a sufficient integration between both drivers.
For the top-end you can start running the Audax without lowpass (or maybe using a series inductor of around 0.1..0.22mH) and operate the Fostex FT17H with just a capacitor in series (around 2.2uF - try a few different values, maybe just buy 1uF X 4 and 0.47uF X 4 and try until it sounds (and maybe measures) right.
Such a system will not be the last word in smoothness and power handling, but it will sound reasonably balanced and even handed, while being very 'direct', 'immediate' and quite exciting sounding. And I think you can actually achieve it. Layer you can upgrade to an active system.
The Audax & Fostex Drivers are both found in some very high priced and well regarded speakers (both Studio & HiFi) and I do not think they will need upgrading, the Peavey BW's you need to keep as long as you your GF, so once you feel the need to improve these speakers you can mess with the crossovers at modest cost or go fully active in steps at greater cost.
Or maybe the speakers will sound just dandy to you and you prefer instead to build a nice tube amplifier kit to drive these speakers...
Anyway, that would be my advise, but you do not have to take it...
Ciao T
PS, I recently designed a speaker that used a 60Hz 1st order crossover. My first very rough cut was just a "textbook" 1st order as described - RC in parallel to the woofer - values calculated from the datasheet, L & C based textbook formula. It sounded and measured much better than one should think.
The finally "fine-tuned" version ended up with some minor value tweaks and the addition of an LCR "trap" to pull down the first breakup resonance of the cone driver, but sonically there was very little to choose between the versions. The final measures notably flatter though...
It's more the latter. Speakers are not a constant impedance, but vary depending on frequency. A crossover is a mix of capacitors, resistors, and inductors. This is called an LRC filter. Change any one of those values and the filter response changes.
The tricky part is that the speaker is one of those components, primarily the resistance, but it also has inductance. Both change with coil temperature and frequency and position of the voice coil on the magnet.
Every speaker is different, so to get a response that you want requires a different filter design for every speaker type you use. That's why there is no universal crossover.
Also, you can buy better components that the off-the-shelf crossovers and that can make a big difference in the sound.
Yeah, good points.
Recently I had a passive XO built replacing my active design and I was kind of shocked at the possible costs. Coils and Caps can get pricey.
Im not pushing the active design, just pointing out cost can get out of hand for passives if the XO gets complicated. You will keep this one simple
Yeah, good points.
Recently I had a passive XO built replacing my active design and I was kind of shocked at the possible costs. Coils and Caps can get pricey.
Im not pushing the active design, just pointing out cost can get out of hand for passives if the XO gets complicated. You will keep this one simple
How true that is. That is one reason I would push away the thought of a 3-way design. Not only is it fraught with lots of pricy components, but it is much trickier to design.
Also, the woofer-mid crossover point tends to be around 400 Hz, and the inductors at those frequencies get big and costly.
I may not be right, but I am kind of looking at this as a best bang for the buck project. Given the constraints (drivers and financing), there quickly comes a point where more doe not yield much of an improvement. So, pragmatic as I may sound I am trying to aim at the sweet spot.
Still, after all is done I think the system will impress the hell of everyone when it is finished and mated to a sub. As my girlfriend id fond of saying, "There will be much joy and happiness."
Ok, I have been considering everything you all guys kindly pointed out and even though I still want to do a 3 way as soon as I can, the money part tells me to start slow and do the 2 way. In the end it is going to be better for many reasons.
First, for the 2 way I will use the Fountek NeoCd2.0M as a tweeter that not only is a real good one but it also looks awesome Then later when I upgrade to the 3 way I can keep it and add the Audax PR170M0 and the final result would be really cool sounding and looking.
The second reason is that now will all the information that I learned form you guys, I am kinda curious to see the differences between a good 2 way and a good 3 way later.
Also as soon as I can start upgrading, I may decide to change the woofer ( if girlfriend permits and then with your help I can choose the best possible one.
So since I see that Loren and Thorsten and very knowledgeable people and I am sure both designs are going to be much more that what I was hoping for, it will be my chance to try both systems.
Now then a question, Loren, you said after Thorsten pointed out that the box for the Peavey could be a vented one,
" I would recommend using the box frequency Peavey uses and set it at 58 Hz. F3 will be 59.5 Hz. For that alignment:
Box is 3.5 cubic feet
vents would be two 4" diameter and 1.23" long each."
Will that still apply for the 2 way? I guess it could right?
Well I guess it is enough questions for now.
Thank you all.
Leo
First, for the 2 way I will use the Fountek NeoCd2.0M as a tweeter that not only is a real good one but it also looks awesome
Then later when I upgrade to the 3 way I can keep it and add the Audax PR170M0 and the final result would be really cool sounding and looking.The second reason is that now will all the information that I learned form you guys, I am kinda curious to see the differences between a good 2 way and a good 3 way later.
Also as soon as I can start upgrading, I may decide to change the woofer ( if girlfriend permits
and then with your help I can choose the best possible one.So since I see that Loren and Thorsten and very knowledgeable people and I am sure both designs are going to be much more that what I was hoping for, it will be my chance to try both systems.
Now then a question, Loren, you said after Thorsten pointed out that the box for the Peavey could be a vented one,
" I would recommend using the box frequency Peavey uses and set it at 58 Hz. F3 will be 59.5 Hz. For that alignment:
Box is 3.5 cubic feet
vents would be two 4" diameter and 1.23" long each."
Will that still apply for the 2 way? I guess it could right?
Well I guess it is enough questions for now.
Thank you all.
Leo
Ok, I have been considering everything you all guys kindly pointed out and even though I still want to do a 3 way as soon as I can, the money part tells me to start slow and do the 2 way. In the end it is going to be better for many reasons.
First, for the 2 way I will use the Fountek NeoCd2.0M as a tweeter that not only is a real good one but it also looks awesome
The second reason is that now will all the information that I learned form you guys, I am kinda curious to see the differences between a good 2 way and a good 3 way later.
Also as soon as I can start upgrading, I may decide to change the woofer ( if girlfriend permits
So since I see that Loren and Thorsten and very knowledgeable people and I am sure both designs are going to be much more that what I was hoping for, it will be my chance to try both systems.
Now then a question, Loren, you said after Thorsten pointed out that the box for the Peavey could be a vented one,
" I would recommend using the box frequency Peavey uses and set it at 58 Hz. F3 will be 59.5 Hz. For that alignment:
Box is 3.5 cubic feet
vents would be two 4" diameter and 1.23" long each."
Will that still apply for the 2 way? I guess it could right?
Well I guess it is enough questions for now.
Thank you all.
Leo
Leo,
This is going to be fun!
Before you cut wood give me a chance to redo the enclosure and crossover using LEAP5. The program just rolled in the door today, so I need to ramp up with it and this will be a good project to cut teeth on.
I looks like that there are driver libraries for the Peavey on the LinearX website for the LEAP suite. This means I should have a better model to work with and the crossover design should be a little more accurate.
It will take a few days to get this going, so hang in there.
We should keep all progress on this blog so everyone has a chance to review and critique the design and progress. There is a lot to do.
Good news! LEAP has the Peavey 1502-8 woofer model in the library. I don't see the Fountek, but that isn't as critical as the woofer.
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