When I play the mid range on its current crossover (0 to 5Khz) I cannot even see it move, even when I'm putting 120Watts into through that crossover into the mid and compression driver.
I'm pretty sure it's not getting too much low frequencies if I can't even see it move, but perhaps I'm wrong. I hate to be so helpless but I know nothing about crossovers, any chance you can help me with what specific value cap I would need?
And I really don't see why I need something to listen to to see how my stuff should sound. It seems like a few people here are saying that somehow I've messed something up. I just don't understand, this setup sounds fine. You all say that I'll have overlap between the woofer and mid, can I hear it, nope. You all say I should've done active crossovers, did I, nope, does it sound good, yes.
I have all the basic elements of a three way setup, a low, mid, and high. I don't understand what I've done that is so wrong as to make all of you think my setup is sub-par. I've done nothing different than all the other homemade PA systems have I not?
And none of you explain your thinking behind your suggestions, nobody seems to say why I should change something. Is it for sound quality, speaker longevity, just to conform?
I'm just so confused, how is it that I've built this setup in such a way that everyone things it sounds horrible? What part of this setup is so poor or questionable that you all question how it sounds?
...but you don't give it any reason to drink!
Please just explain how I can benefit from a PLLXO and I'd be happy to consider building one. One of the benefits I see from that is since its before the amps, I don't need huge passive crossovers on the outputs of the amp for large power handling.
So far you've said:
"i don't know that it will work the way you expect but who am i to say i've heard stranger contraptions produce great results! " and I'm still wondering what I've done that is so weird that it is to be called a contraption, you never answered.
"i hope it wasn't your x-over configuration turning into a bad/weird reactive load that hurt the la601" I asked what you meant by reactive load, you never answered.
"an iron core on an inductor meant for audio?sorry that just spells bad to me!" I asked why its bad, you never answered.
I don't mean to sound rude but I'm just confused. More questions are getting created than answered. I appreciate all the help, I really do.
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I guess I'm just a bit offended that everyone assumes this system sounds bad for some undisclosed reason, without ever hearing how it actually sounds.
I think I have a solution. When I fix my amp, I'll get a nice video of this system up and running, then you guys can watch it, and then really hear how it sounds, then tell me if it sounds good or bad. I'll accept it if you tell me it sounds bad after you've watched the video, but for now, I can't accept someones opinion based on assumptions.
In the meantime: I'll be ordering caps for my amps soon, so if we can figure out an easy solution to making my mid a band pass, perhaps I can order those parts when I order the caps for my amps.
Thanks for the help.
I think I have a solution. When I fix my amp, I'll get a nice video of this system up and running, then you guys can watch it, and then really hear how it sounds, then tell me if it sounds good or bad. I'll accept it if you tell me it sounds bad after you've watched the video, but for now, I can't accept someones opinion based on assumptions.
In the meantime: I'll be ordering caps for my amps soon, so if we can figure out an easy solution to making my mid a band pass, perhaps I can order those parts when I order the caps for my amps.
Thanks for the help.
I understand that you're frustrated.
From our point of view, you've got together a bunch of budget drivers, and crossed them over in a very very simplistic fashion, without any measurements.
I'll be honest, the chance of the above sounding properly good is very slim.
I recommended that you buy a pair of Behringers so that we're both on the same page. If you tell me that your set-up has a bit more low-end heft than the Behringers, that's fine. I know exactly what you're referring to. But after you've said
I think its worth you having something to refer to.
To find out what size capacitors you need, measure the input impedance of your mid amplifier, and use the usual formula to find out what size cap you need. Chances are it won't be a standard size, but you can parallel up a couple of smaller ones - just add the values until its roughly the value you want.
Chris
From our point of view, you've got together a bunch of budget drivers, and crossed them over in a very very simplistic fashion, without any measurements.
I'll be honest, the chance of the above sounding properly good is very slim.
I recommended that you buy a pair of Behringers so that we're both on the same page. If you tell me that your set-up has a bit more low-end heft than the Behringers, that's fine. I know exactly what you're referring to. But after you've said
I think its worth you having something to refer to.
To find out what size capacitors you need, measure the input impedance of your mid amplifier, and use the usual formula to find out what size cap you need. Chances are it won't be a standard size, but you can parallel up a couple of smaller ones - just add the values until its roughly the value you want.
Chris
Thank you for explaining your thinking. Now may I ask what measurements you mean, and also what you think would be a better crossover (I thought more simple is better)?
Maybe I'm wrong but I thought most cheap little pa systems that wanna-be dj's buy are just boxes full of cheap drivers with simple passive crossovers after a small power amp... I thought I was doing the same, just homemade instead of prebuilt...
Welp since I'm cheap and don't want to waste money on reference speakers, Ill make a video of my system when the amps are repaired, and I'll let you do the judging. That way I don't have to spend money and I also have someone else to compare my system. 2 birds with 1 stone
On my mid/high amp it tells me the input impediance but I have no idea what formula your referring to.
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Tube Amper
i understand that the word "contraption" can have a negative connotation but i wasn't saying it doesn't sound good quite the contrary.
i guess for me the uncertainty that the mid driver might fail from thermal stress due to it's having to deal with frequencies it can't reproduce is something that i would address but that's me.
as to the crossover behaving like a reactive load that becomes a subject i'm still learning about so my comment on this subject could be tainted by my lack of knowledge but from my understanding an iron core coil will exhibit saturation distortion far sooner than an air core coil(this is quite audible especially in cheap and cheery home theater sub's which is the reason so many receiver sub amps die but that's a whole other topic) the other thing that comes to mind is magnetic coupling if you mount this inductor(x-over coil) in or on the sub are you close enough to be within the magnetic field of the driver, that iron core coil could be forming a transformer across your sub and amp.
as to furthering your understanding of reactive loads sorry not a good teacher like i said i'm still learning but there mounds of info to go through.
i guess my approach to system design based on what knowledge i've acquired over the years would have me doing things differently no offense.
p.s. if the horse needs a reason to drink he's obviously not thristy.
i understand that the word "contraption" can have a negative connotation but i wasn't saying it doesn't sound good quite the contrary.
i guess for me the uncertainty that the mid driver might fail from thermal stress due to it's having to deal with frequencies it can't reproduce is something that i would address but that's me.
as to the crossover behaving like a reactive load that becomes a subject i'm still learning about so my comment on this subject could be tainted by my lack of knowledge but from my understanding an iron core coil will exhibit saturation distortion far sooner than an air core coil(this is quite audible especially in cheap and cheery home theater sub's which is the reason so many receiver sub amps die but that's a whole other topic) the other thing that comes to mind is magnetic coupling if you mount this inductor(x-over coil) in or on the sub are you close enough to be within the magnetic field of the driver, that iron core coil could be forming a transformer across your sub and amp.
as to furthering your understanding of reactive loads sorry not a good teacher like i said i'm still learning but there mounds of info to go through.
i guess my approach to system design based on what knowledge i've acquired over the years would have me doing things differently no offense.
p.s. if the horse needs a reason to drink he's obviously not thristy.
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His mids are fine. The Behringer A500 amplifier supplies 125w RMS into 8ohms, the Pyle PDMR6 Sealed Back speakers have a 150w RMS power rating, 300w program power. Power handling is not a concern. Closed back midranges have a high resonant frequency which after response drops off substantially. Pyle does not release response graphs, attached is a realistic example by Eminence. There will be a small amount of overlap from ~400hz to ~800hz.
Simpler is better, don't worry about putting a high pass on the mids. If you want to be technically correct, you could cross the 15" drivers at 400hz instead of 800hz. You may be more pleased with this sound, too. Listening to the system with the 15" driver disconnected is a good idea. Experimenting by crossing over the 15" @ 300hz or 400hz with a 5.1 sound card and foobar2000 is an excellent idea. It is free to you, and you may end up improving on your already satisfying sound. Or, if you are simply happy with the way it is, don't change anything.
Simpler is better, don't worry about putting a high pass on the mids. If you want to be technically correct, you could cross the 15" drivers at 400hz instead of 800hz. You may be more pleased with this sound, too. Listening to the system with the 15" driver disconnected is a good idea. Experimenting by crossing over the 15" @ 300hz or 400hz with a 5.1 sound card and foobar2000 is an excellent idea. It is free to you, and you may end up improving on your already satisfying sound. Or, if you are simply happy with the way it is, don't change anything.
Attachments
Thank you for bringing some truly helpful and reliable information into this thread.
Hopefully now people will stop nagging about that mid range blowing itself up, however please note that I will be throwing the behringer a500 into bridge mode to power the mids & highs as soon as I get the other channel fixed (yes both my amps need filter caps).
What exactly is the issue with having sound overlap like that? Does this not happen when you play a song on stereo speakers? 2 speakers playing almost the same sound. Why is it bad in my situation per say?
I'd like to get your opinon on it but don't you think it'd be better for me to slap a High pass on the mid than to lower the low pass on my woofer?
You really surprised me on that post there.Apparently you do have the knowledge to back up what you say, you just need to share it more often.
As far as you not knowing enough about reactive loads, pfft, looks like you know enough to me! I now understand your concerns.
Lets try this, lets say someone gave you a cubo15 with a Behringer 15W300A8 woofer in it, a pyle 6.5" mid, and a pyle compression driver and horn, what would you do with those (besides buy things to replace them, that is not an option
)?In order answer your question properly, I will need to explain an often overlooked element in speaker design called phase. All speakers have phase, and it is equally important as frequency response or power handling.
Phase may sound like a mysterious word, but you can simply think of phase as timing. Phase is the timing a speaker has in playing a sound when it receives a signal from the amplifier. If the driver is manufactured perfectly, it will have a flat phase response. A flat phase response is equally desirable as a flat frequency response.
In basic terms, when two speakers try to play the same range of frequencies, they can mess up their timing (phase), causing the quality of the sound to be degraded. This is the first reason to cross the 15" driver lower, so it doesn't interfere with the phase of the mid. When two drivers interfere, it is called "comb filtering."
The second reason to cross the 15" driver at a lower frequency is mass. The mass of the driver also affects phase. The more massive a driver is, the more energy it takes to move, and the slower it will be to respond to the signal. To give contrast, the only speakers with flat phase response are planar drivers, such as isodynamic planar drivers and ribbon drivers. These speakers have extremely little mass, as the element which moves to make sound is essentially a thin ribbon suspended in the air by a magnetic field. The 15" and 6-1/2" drivers we are dealing with here are called piston drivers, just for reference.
The second reason is not absolute. Piston drivers have the biggest phase problems near the resonant frequency. The resonant frequency occurs where you can see the huge impedance spike in the attachment on my last post. Right at this spike is where the frequency drops off. Theoretically, it would be appropriate to consider putting the midrange driver on a bandpass to avoid this frequency altogether and cross over above it.
However, there is a catch. The very act of using a crossover negatively affects phase. This is the reason behind "simpler is better." Without advanced calibration tools and complex spreadsheets, it is impossible to get the phase problems introduced by a crossover under control. Therefore, it is good to use as little crossover as possible. Thus, the third reason, it would be simpler to have the system crossover over at ~400hz, assuming you want to avoid the issues addressed by the first reason.
But there is still more to consider. Power handling. That amp can supply 375 watts RMS @ 8 ohms in bridged mono mode. This will almost certainly kill your midrange. If you want to avoid killing your midrange, but still wish to use that much power, you will need to put a highpass filter on it. I propose two alternatives.
One alternative, use a simple in-line crossover going to your amp. This will still affect phase, as all crossovers do, but it will not interact with the other crossover causing unknown effects. FMOD Crossover Pair 500 Hz High Pass | 266-280 Unfortunately, they do not make a 800hz high pass in line crossover. Disclaimer: I make no guarantee a crossover of any type will prevent your mid from being burned up with that much power.
The second alternative: Don't bridge. That is a huge amount of power, and it probably won't be as loud as you think with that much wattage. Unfortunately, according to physics, power in does not equal decibels out, you get diminishing returns when adding more power. Here is an example: Your Pyle speakers have a sensitivity of 93db. If the speakers are within a few feet of a wall and you listen at a distance of 8 feet, at maximum volume your amp in dual channel mode (125w) will output 109.2db. In bridged mode (375w), that only increases to a total of 114db. You can see for yourself with this calculator: Peak SPL Calculator In short, you more than double wattage going to the speakers, but only increase volume by 4.8db! Not very much of an increase.
The second alternative continued: Towards the beginning of the thread you were enthusiastic about tri-amping your speakers. Why not tri amp? You still can do this, even with passive crossovers. You will need to split the highpass and lowpass circuitry in the "2-Way 8 Ohm 5,000 Hz 150W" crossover you purchased. You can dedicate "output 1" on your Behringer A500 amp for your mid, and "output 2" to your compression tweeter.
I hope this helps.
Phase may sound like a mysterious word, but you can simply think of phase as timing. Phase is the timing a speaker has in playing a sound when it receives a signal from the amplifier. If the driver is manufactured perfectly, it will have a flat phase response. A flat phase response is equally desirable as a flat frequency response.
In basic terms, when two speakers try to play the same range of frequencies, they can mess up their timing (phase), causing the quality of the sound to be degraded. This is the first reason to cross the 15" driver lower, so it doesn't interfere with the phase of the mid. When two drivers interfere, it is called "comb filtering."
The second reason to cross the 15" driver at a lower frequency is mass. The mass of the driver also affects phase. The more massive a driver is, the more energy it takes to move, and the slower it will be to respond to the signal. To give contrast, the only speakers with flat phase response are planar drivers, such as isodynamic planar drivers and ribbon drivers. These speakers have extremely little mass, as the element which moves to make sound is essentially a thin ribbon suspended in the air by a magnetic field. The 15" and 6-1/2" drivers we are dealing with here are called piston drivers, just for reference.
The second reason is not absolute. Piston drivers have the biggest phase problems near the resonant frequency. The resonant frequency occurs where you can see the huge impedance spike in the attachment on my last post. Right at this spike is where the frequency drops off. Theoretically, it would be appropriate to consider putting the midrange driver on a bandpass to avoid this frequency altogether and cross over above it.
However, there is a catch. The very act of using a crossover negatively affects phase. This is the reason behind "simpler is better." Without advanced calibration tools and complex spreadsheets, it is impossible to get the phase problems introduced by a crossover under control. Therefore, it is good to use as little crossover as possible. Thus, the third reason, it would be simpler to have the system crossover over at ~400hz, assuming you want to avoid the issues addressed by the first reason.
But there is still more to consider. Power handling. That amp can supply 375 watts RMS @ 8 ohms in bridged mono mode. This will almost certainly kill your midrange. If you want to avoid killing your midrange, but still wish to use that much power, you will need to put a highpass filter on it. I propose two alternatives.
One alternative, use a simple in-line crossover going to your amp. This will still affect phase, as all crossovers do, but it will not interact with the other crossover causing unknown effects. FMOD Crossover Pair 500 Hz High Pass | 266-280 Unfortunately, they do not make a 800hz high pass in line crossover. Disclaimer: I make no guarantee a crossover of any type will prevent your mid from being burned up with that much power.
The second alternative: Don't bridge. That is a huge amount of power, and it probably won't be as loud as you think with that much wattage. Unfortunately, according to physics, power in does not equal decibels out, you get diminishing returns when adding more power. Here is an example: Your Pyle speakers have a sensitivity of 93db. If the speakers are within a few feet of a wall and you listen at a distance of 8 feet, at maximum volume your amp in dual channel mode (125w) will output 109.2db. In bridged mode (375w), that only increases to a total of 114db. You can see for yourself with this calculator: Peak SPL Calculator In short, you more than double wattage going to the speakers, but only increase volume by 4.8db! Not very much of an increase.
The second alternative continued: Towards the beginning of the thread you were enthusiastic about tri-amping your speakers. Why not tri amp? You still can do this, even with passive crossovers. You will need to split the highpass and lowpass circuitry in the "2-Way 8 Ohm 5,000 Hz 150W" crossover you purchased. You can dedicate "output 1" on your Behringer A500 amp for your mid, and "output 2" to your compression tweeter.
I hope this helps.
Forgot to answer one of your questions:
Excellent question. The truth is, it does. You have to take into account driver distance. In general and super simplified terms for stereo pairs: When separated with distance only the low frequencies--which radiate differently than high frequencies--are affected by comb filtering. The change in radiation happens to be right at 100hz. Frequencies above 100hz are not affected, frequencies 100hz and below are subject to comb filtering issues.
The distance between drivers at which comb filtering becomes an issue is also affected by frequency. Lower frequencies can be further apart before they become affected by comb filtering, whereas the top of the spectrum must have less than an inch driver center-to-center spacing. Therefore, the higher up you are, the more you need to worry about it. In your specific case: Crossing over at 300 or 400hz should not introduce comb filtering, but 800hz, for similar reasons why speaker "beaming" occurs, will most likely be a problem for you unless you take great pains to make the rims of the two drivers practically touch. Which to my understanding, they are separate boxes and thus susceptible to the issue at this frequency.
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In my efforts to copy my thoughts down into this forum I neglected the most important detail. Phase smearing, although I'm sure different people call it different things, is even more detrimental than comb filtering. It is simple to explain. Your 6-1/2" Pyle has a certain phase or timing. Your 15" Behringer has a different timing. These timings are further impacted by the crossovers on both. If both drivers try to play the same frequency range at the same volume with different timings, you can imagine how it will reduce sound quality.
Imagine a duet of violinists playing the same piece of music. One plays at a constant speed, but the second plays lower notes slower and higher notes faster. A bit of an extreme example, but you get the effect.
Imagine a duet of violinists playing the same piece of music. One plays at a constant speed, but the second plays lower notes slower and higher notes faster. A bit of an extreme example, but you get the effect.
I see what the problem is with all this phase stuff. I know exactly what your talking about but I just never put 2 and 2 together and said, hey, maybe my setup has this issue with phase separation and what not.
However I'm now wondering what benefits I would get from splitting the crossover, and thus having a tri-amped setup. How is that any different than what I already have?
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That question starts to get into answers I have not purposely done research on, but I seemed to have passively pick up somewhat of a response just by being around. Maybe someone else can clarify, but I believe the answer is also phase. Given what an individual amplifier sees, a "multi-amp" system will be more simple. This gives the amp more "control" over the driver. I am sorry for being ultra vague here, I do not have a solid answer. In the future I will branch my knowledge into amplifier design and construction. By then I will be able to clarify.
That probably won't satisfy you for now, so the best I can tell you is just try it out. It shouldn't be too hard to separate the components from the board and re-solder. I didn't mean to suggest tri-amping as something you should do, just something that is possible.
Edit: On the other hand, you could not tri amp and not worry about fixing the other channel of your amplifier.
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Well I appreciate the suggestion, but until I can get a good reason, I think I'll just leave it together. Although, who knows, maybe I'll get bored and decide to try it, because really it can't hurt.
As far as the Behringer A500 goes, the one channel that is broken is like that from how I received it 2 weeks ago. It is currently disconnected, I believe the only thing wrong is the one filter cap that fell off of the board. The legs are completely ripped off of the cap, but its one of those snap in caps so it has those large pads on the bottom that almost look like rivets, I'm almost tempted to solder on some "legs" to the bottom of the cap and wire it in and see if that channel of the amp works. Then again said cap has a slight dent in it as well......
tube amper
have you taken the time to look up PLLXO (Passive Line Level X-Over) a google search should lead to the acticle/page i'm talking about from there you should be able to understand what i'd do.
it would be easy for me to tell you "what i would do" but would you learn anything from it?
i've learned that i'm going to have to review some physics texts i guess i missed a few things about phase and wave propagation...
have you taken the time to look up PLLXO (Passive Line Level X-Over) a google search should lead to the acticle/page i'm talking about from there you should be able to understand what i'd do.
it would be easy for me to tell you "what i would do" but would you learn anything from it?
i've learned that i'm going to have to review some physics texts i guess i missed a few things about phase and wave propagation...
Could you post a picture of this capacitor and it's mount?
You could try one of these for your 15" instead of that speaker level crossover:
FMOD Crossover Pair 500 Hz Low Pass | 266-260
FMOD Crossover Pair 200 Hz Low Pass | 266-258
These are essentially a neat and tidy PLLXO like what turk was talking about. There is a good chance they will sound better, and either of them would be a more appropriate crossover frequency. If you push the 15" a great deal louder than the satellites, you may want the 200hz filter as higher frequencies will still be evident at un-equal volumes. If you keep the volumes fairly equal you will most likely be more satisfied with the 500Hz filter.
True words.
You could try one of these for your 15" instead of that speaker level crossover:
FMOD Crossover Pair 500 Hz Low Pass | 266-260
FMOD Crossover Pair 200 Hz Low Pass | 266-258
These are essentially a neat and tidy PLLXO like what turk was talking about. There is a good chance they will sound better, and either of them would be a more appropriate crossover frequency. If you push the 15" a great deal louder than the satellites, you may want the 200hz filter as higher frequencies will still be evident at un-equal volumes. If you keep the volumes fairly equal you will most likely be more satisfied with the 500Hz filter.
True words.
Wait. We keep forgetting about the foobar2000 option. This is a great testing alternative. If you can take the effort to set it up, you can test for yourself the difference between the 200hz or the 500hz filters. I'm just a guy you've never met on the internet, it's better to base your actions on your own experience. Getting crossover experience from foobar2000 will be enlightening for you. Try it with all of your speakers. You could fix your A500 amp, tri amp the system, (don't forget to take out all current passive crossovers) then test all feasible crossover points on the fly. Once you find a crossover point you like, you can commit it to hardware and stop relying on foobar.
This method is simpler than empirical testing-and-math, and it can potentially produce equal results if you are patient.
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I already know about PLLXO's. But you never explicitly said that you would impliment them yourself and that'd be the end of the story.
And yes I would learn from you telling me what I would do. Going by your logic I should not give a thought about you saying my system probably has issues, because what would I care about you. But really that's the whole point of a forum, I can sit there all day long and google this and that but I wouldn't know specifically what to google, where to start, etc. Also if I see what you do then I know you are knowledgeable and not one of those audiophools that walk around thinking in their heads, "I have such nice stuff so this guys must automatically be sub-par", which is honestly how I originally thought you were, but after your last few posts you have more than proven that you definitely can back up what your saying with facts and knowledge.
Well my main PC is real nice and has like 7.1channel audio, problem is that my little PA setup is currently sitting in the garage, as I still haven't even made an enclosure for the mids and highs, so you can see that although foobar2000 itself is easy, moving my 70lb woofer, the mids and highs, and the 70lbs worth of audio equipment into my room with my main pc (which is where it is supposed to go when its all said and done) is quite a task.
At the same time perhaps I'm not fit for the job persay. If I think it already sounds delightful as is, perhaps I won't be able to find crossover frequencies that sound better, let alone, if I did, would it be enough difference to make me justify buying all new crossovers...
Here is probably the most important few questions, which I should've asked long ago. Based on the info you know of my current setup, what would you compare it to? Then based on modifying the crossovers to how you would like, perhaps woofer low pass at 400hz, and then separate the mid and highs, as well as put the mid on a bandpass from 400-5Khz what would you compare that to? Because really, if you tell me that you would assume it sounds about as good as the average small town DJ, and your trying to get me to get it to sound like some clean clear system that would please a true audiophiles ear, then really its not nessary. However if you assume it sounds worse, and are only trying to bring it up to sound like the average dj, then I can understand that.
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I understand, you are concerned with relativity. Before I answer that, I have two questions for you: Does the overall system volume level satisfy you? Are you going to leave the system in mono, or eventually expand to stereo?
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