I have a tweeter making a faint hiss with no wires plugged into it? as in not plugged into the amplifier or any circuit at all. just hooked up in parallel with a speaker. I dont know how it makes a noise but it does if I put my ear a few inches from it. the other one doesnt do that when unplugged i'm not sure how its possible for a tweeter to make any audible sound without even being plugged into anything at all.
back-emf from the other speaker most likely. Have you ever tried using a speaker as a microphone?
Tony.
Tony.
that makes it part of a circuit.
If it was running for a long enough time with enough power, that may explain the hissing sound. (may be fried)
Disconnect it and check the dc resistance with a multimeter.
Lightly tap or scratch the woofer cone, and you will probably hear more from the tweeter.
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Tony is correct. The movement of your midrange voice coil in a magnet field generates an electrical current which you have wired in parallel with the tweeter.
-Maxwell's Equations.
-Faraday's field equations.
-Lorentz Force Law.
... and for Apogee ribbon speakers....Emil Lenz left-handed, 3-finger force law!
The pole piece on many tweeters is open for ventilation, and an air path from the midrange air volume could be moving the tweeter dome. The better cabinets seal the tweeter's rear air volume - some add a pinch of fiberglass for absorption.
Do you have a house cat? 🙂
Could be sea shell effect ?
Its just the horn phasing the high frequency sound coming in and sounding like the sea.
A noisy magnetic field (e.g. from PSUs or other large transformers or electric motoers etc) picked up by the crossover's coils ?
Regards
Charles
Regards
Charles
there is no crossover coils. tweeter uses a capacitor. speaker has no crossover components. raw speaker in parallel with the tweeter.
somehow the tweeter is getting electricity to make white noise faintly.
and there is absolutely no amplifier plugged into the speaker or the tweeter. completely unplugged from any possible power source.
The tweeter has no pole piece. its inside a flat cylinder plastic housing with a fine metal grill on the front. no tweeter cone is visible. but I can see holes and supporting plastic from the center outward. I think its some kind of piezo tweeter possibly.
I dont hear it on the other tweeter. just one.
I noticed it gets louder with my computer. computer monitor. and stuff turned on. but i can still hear it a little with all my stuff turned off.
but its no where remotely near any large power transformers or electric motors/inductive loads
I have no pets here. pets are not allowed where I live
both the speaker and tweeter still work fine. sounds great when playing music. both tweeters. i just dont know how one of them somehow is getting phantom electricity of a white noise with no wires attached to it.
somehow the tweeter is getting electricity to make white noise faintly.
and there is absolutely no amplifier plugged into the speaker or the tweeter. completely unplugged from any possible power source.
The tweeter has no pole piece. its inside a flat cylinder plastic housing with a fine metal grill on the front. no tweeter cone is visible. but I can see holes and supporting plastic from the center outward. I think its some kind of piezo tweeter possibly.
I dont hear it on the other tweeter. just one.
I noticed it gets louder with my computer. computer monitor. and stuff turned on. but i can still hear it a little with all my stuff turned off.
but its no where remotely near any large power transformers or electric motors/inductive loads
I have no pets here. pets are not allowed where I live
both the speaker and tweeter still work fine. sounds great when playing music. both tweeters. i just dont know how one of them somehow is getting phantom electricity of a white noise with no wires attached to it.
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Maybe it's the the tweeter cap ,does it stop after a while ? have you tried swapping speaker wires to see if it's from the amp ?
A piezo tweeter is capacitive in nature. Wiring it in parallel with the inductance of the main speaker may constitute a tuned circuit which is picking up the high frequency radio noise radiated from your computer equipment. Perhaps someone can do the maths to see if this explanation is possible?
Since this phenomenon only occurs in one of the tweeters, a fault in the mechanical construction of the suspect tweeter may be responsible for converting the 'tuned in' energy into sound. A replacement tweeter is therefore the likely solution.
Since this phenomenon only occurs in one of the tweeters, a fault in the mechanical construction of the suspect tweeter may be responsible for converting the 'tuned in' energy into sound. A replacement tweeter is therefore the likely solution.
its only noticable within a few inches though. not very loud. cant be heard from my normal sitting position. but I still think its a bit weird!
and like i said it does it when its not plugged into the amp. so theres no wires to swap.
and like i said it does it when its not plugged into the amp. so theres no wires to swap.
If possible, take the speaker outside in the quiet of night, far away from your electronics, and listen for the hiss. This may confirm whether the noise is due to RF pickup. or not.
It's also worth experimenting by wiring a 22 ohm resistor in parallel with the piezo tweeter.
This has certain advantages sound wise. See this site:
Frugal-phile | Piezo Tweeter Crossovers | J Risch
This has certain advantages sound wise. See this site:
Frugal-phile | Piezo Tweeter Crossovers | J Risch
Piexo tweeter? Then it was definitely back EMF. Won’t take much cone movement since the tweeter is almost no load at all. A regular tweeter (or resistor in parallel) is a much heavier load and takes more cone movement to generate SPL out of the tweeter.
If you were just using a crossover cap and nothing else on the tweeter it’s no surprise it sounds better with the resistor in parallel. The resistor is required when using a conventional crossover with a piezo, whether it’s just a cap or some higher order network. Nobody ever uses one, and then they complain about how bad it sounds. 1/(2piRC) will give your effective crossover frequency. It will be lower for a 22 ohm resistor than an 8 ohm, but it’s way better no filtering at all.
If you were just using a crossover cap and nothing else on the tweeter it’s no surprise it sounds better with the resistor in parallel. The resistor is required when using a conventional crossover with a piezo, whether it’s just a cap or some higher order network. Nobody ever uses one, and then they complain about how bad it sounds. 1/(2piRC) will give your effective crossover frequency. It will be lower for a 22 ohm resistor than an 8 ohm, but it’s way better no filtering at all.
it has a capacitor as well as a resistor and I also put a resistor in series to reduce the volume slightly since it was a bit louder compared to the speakers volume.
the main speaker seems to be made such that it doesn't need its own crossover. dust cap and cone material and build made to be its own crossover somehow.
maybe it does need a crossover i dont know but it sounds great now
the main speaker seems to be made such that it doesn't need its own crossover. dust cap and cone material and build made to be its own crossover somehow.
maybe it does need a crossover i dont know but it sounds great now
Oh dear … You have a strong electric field under Your house, or perhaps it is acting like a seismograph picking up earthquakes. It could be haunted too. I would call the Ghostbusters.
I was thinking you may have discovered a way to generate electricity using ambiant sounds..../surrounding vibrations that match conebox resonences and then connect to a circit
whats the current? likely very low but still... if you got a woofer by a water fall I wonder if you could light a led.. some how You have to convert to dc I guess. hmm
whats the current? likely very low but still... if you got a woofer by a water fall I wonder if you could light a led.. some how You have to convert to dc I guess. hmm