Electronic cross overs are preferred for at least three reasons off-hand.
1) parts are less expensive. Try pricing the cost of a single 10uF/200V polyester cap!
2) digital domain allows for features you just can't get in passive networks like time delay to match physical offset.
3) efficiency. total sound output is greater, as there are less losses.
Behringer DCX2496
DBX DriveRack PA+
1) parts are less expensive. Try pricing the cost of a single 10uF/200V polyester cap!
2) digital domain allows for features you just can't get in passive networks like time delay to match physical offset.
3) efficiency. total sound output is greater, as there are less losses.
Behringer DCX2496
DBX DriveRack PA+
right thanks for clarifying that. active crossovers are going to be more efficient than passive ones.
i was wondering about combining the left and right signals before the amp or after it. which would be a better idea.
most sub notes are mono, but what if there are ones that are not. will positive or minus be sent the wrong way somewhere?
i was wondering about combining the left and right signals before the amp or after it. which would be a better idea.
most sub notes are mono, but what if there are ones that are not. will positive or minus be sent the wrong way somewhere?
According Boltzmann's constant, proved by Max Planck around 1900, the energy of an electron is dependent on its temperature. Just heat them up a bit to restore them to like new condition.
Make sure to use pure silver wire (about 10 lbs per foot) in a pure radon environment not greater than 2 atmospheres of pressure for the effect to stabilize the particles. I heat my radon to 295.15 degrees Kelvin. Think of it as a vulcanization process.
Did you know that a petabyte of data weighs 2.89 grams?
I'm so FOS
Make sure to use pure silver wire (about 10 lbs per foot) in a pure radon environment not greater than 2 atmospheres of pressure for the effect to stabilize the particles. I heat my radon to 295.15 degrees Kelvin. Think of it as a vulcanization process.
Did you know that a petabyte of data weighs 2.89 grams?
I'm so FOS
I heat my radon to 295.15 degrees Kelvin. Think of it as a vulcanization process....I'm so FOS
Live long and prosper dave....
I've been living happily with mixed-bass and a 140 Hz (18 dB/8ave) electronic cross-over since 1968. At 90 Hz, you aren't keeping much bass out of the mid-range drivers.
Long ago at Bell Labs, I had a buddy who used full-range Klischorns but added a mixed-bass below 40 Hz. Then he built a house with a room suitable for playing his system in.
I ordinarily couldn't care less about definitions that arbitrarily distinguish stuff like woofers from subwoofers.
Maybe we are going to flame into Golden Ear territory, but there sure isn't sound localization with a 140 Hz 18 dB/8ave crossover woofer. i'd guess that with a woofer sitting sort of near the mid-ranges and a sharp slope cross-over, 200 Hz would be OK.
I used to listen to a system with Ionovac tweeters. Only a slight exaggeration to say that all the sound seemed to emanate from them, regardless of what the other drivers were up to.
Maybe we are going to flame into Golden Ear territory, but there sure isn't sound localization with a 140 Hz 18 dB/8ave crossover woofer. i'd guess that with a woofer sitting sort of near the mid-ranges and a sharp slope cross-over, 200 Hz would be OK.
I used to listen to a system with Ionovac tweeters. Only a slight exaggeration to say that all the sound seemed to emanate from them, regardless of what the other drivers were up to.
Here we go into the realm of hearing measurements without blind testing.
What was your cross-over slope? That is crucial.
You talk as if the shift was detectable with all kinds of sources. Remarkably little content in the low range. Very wonderful when it is there, of course.
Lots of ways to do things ineptly. For example, having detectable harmonics, noise, and crap coming out of you woofer will sure "help" localization and very immediately.
As generations of testing have shown, localization is not a matter of where you have some LF content even when a pure tone could be localized (maybe that would be above 100 Hz in a music room, just speculating. The upper partials grab the localization and, to be best of my knowledge, there is no subtle shifting as you describe.
Probably 18dB/oct, I don't remember. It was outside in 1/2 space.
An externally hosted image should be here but it was not working when we last tested it.
Inside, I'm sure things will be more forgiving depending on the layout of the guy's space. In my living room, my sub is off to the left to balance the open space into the dining room. Without it, the low end is right heavy due to the corner on the right.
I cross at 90Hz, and can't tell where the sub is. If I raise the crossover frequency, I start to hear it telling me some of the sound is coming from the floor.
i am more concerned whether combining the left and right signal after the amp would be bad for it if there was a difference in left and right signal that low(usually not).
i have done quite a lot of left and right experimentation in the low bass/sub area(mostly stereo bass guitar) and found out that you can very easily get cancellation and muted areas in a room. i gave up on that a long time ago and just run the high mids/tweeters in stereo only.
i have done quite a lot of left and right experimentation in the low bass/sub area(mostly stereo bass guitar) and found out that you can very easily get cancellation and muted areas in a room. i gave up on that a long time ago and just run the high mids/tweeters in stereo only.
First off, you can't "combine" two low impedance sources to feed a single load. That's called passive summing. It sums them across the output impedance of the amplifier. As we know, modern transistor/MOSFET amps have ZERO output impedance due to feedback, the result will not be effective.
Have a fire extinguisher handy.
Or if you do want to use passive summing more correctly, you will have to take a voltage loss across some sizable resistors that will make considerable heat instead of sound through the loudspeaker.
Have a fire extinguisher handy.
Or if you do want to use passive summing more correctly, you will have to take a voltage loss across some sizable resistors that will make considerable heat instead of sound through the loudspeaker.
Okay, thinking about this more... I don't know if it would work, but if the driver has 2 voice coils, run one for left, the other for right.
The best you could hope for in a crossover slope would be 12dB per octave. Let's assume you aren't going to provide some sort additional leveling such as a Linkwitz transform.
If we assume each coil is 4 Ohms, and we want a crossover at 90Hz we'd need an air-core coil of 10.004 mH and a bi-polar capacitor of 312.57184 uF. The cap is in parallel with the driver. The coil is in series prior to them.
Now to keep the bass off of your full range speakers, use the same approach, but inverted. A 10mH coil is in parallel with each speaker, and a 312.57184 uF cap is in series prior to the speaker (assuming it is 8 ohms).
Double check my math before purchasing anything.
Anyone know if this would/wouldn't work?
The best you could hope for in a crossover slope would be 12dB per octave. Let's assume you aren't going to provide some sort additional leveling such as a Linkwitz transform.
If we assume each coil is 4 Ohms, and we want a crossover at 90Hz we'd need an air-core coil of 10.004 mH and a bi-polar capacitor of 312.57184 uF. The cap is in parallel with the driver. The coil is in series prior to them.
Now to keep the bass off of your full range speakers, use the same approach, but inverted. A 10mH coil is in parallel with each speaker, and a 312.57184 uF cap is in series prior to the speaker (assuming it is 8 ohms).
Double check my math before purchasing anything.
Anyone know if this would/wouldn't work?
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First of all, DON'T use passive sub crossovers. Due to impedances of subs and satellites, they simply cannot work. Been there, simulated it, tested it...er sold it anyway...but it just doesn't work worth a damn.
Second, somewhere you need an electronic summing stage. Don't just connect L & R positive leads together, because then any out-of-phase information can basically act like a bit of a short circuit to the preamp or crossover.
Really, you need a crossover with a built-in sub output. Most receivers have such an output, driven by home theater considerations.
Second, somewhere you need an electronic summing stage. Don't just connect L & R positive leads together, because then any out-of-phase information can basically act like a bit of a short circuit to the preamp or crossover.
Really, you need a crossover with a built-in sub output. Most receivers have such an output, driven by home theater considerations.
I think I need an explanation. Sum means sum. 180 degrees out of phase, whenever it randomly occurs, happens in your head-space just like in a resistor and in your room or a concert hall.
Is there some way you can add signals that are 180 degrees out of phase and not have them cancel?
For several good reasons, I favor systems with mixed-bass woofers. But even without trying it, I bet two subs, even playing the same signal, sounds different, maybe even illusory sort of, fuller. That's not the same as saying "more veridical"... a discussion for another day.
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