Great video, thanks for sharing! Subbed. Please note that modern speakers do still use electromagnets. More accurately, modern speakers no longer use electromagnets for the field coil, but the voice coil is an electromagnet and thus vibrates against the permanent magnet when power is modulated through the voice coil.
Thanks, Samy, appreciate the sub and excellent comment. Yes, in this video I didn’t want to get ahead of myself and focused only on the field coil. The voice coil is described in a later video in the series called, “How does a speaker work...” There, the function of the voice coil as an electromagnet is discussed. ruclips.net/video/TYxfdg6yfOk/видео.html
Your explanation or contention is quite weird. A moving coil speaker (or a microphone) is a transducer, which means it converts energy in one form to the other. A speaker converts electrical energy (power) into acoustic energy. If both the field and the armature happen to be of permanent magnets there won't be anything happening. In a static magnetic field if a conductor moves a current would be induced; this is a dynamo. In the same static magnetic field a current is passed in a conductor the conductor would move. Remember the Fleming's left hand rule for the motor and the right hand rule for the dynamo. In the beginning people had used electromagnet for providing the magnetic field in which the armature, the voice coil of the speaker moved. The added feature is that it offered the other important function of chocking the AC ripples in the rectified power to the radio. The people of those days had real sense in doing something. We should be able to appreciate it. Now a days it's not needed because of the availability of very strong permanent magnets, the Neodymium alloy being the strongest till now.
Thanks for the video! I have a question if I may ask... I have a big, and very heavy, 12" Field Coil speaker that came out of an old Hammond Organ and I want to use it with a Guitar amplifier. I'm sure every Field Coil is different but, would I generally use the B+ coming off the Guitar amplifier to power the electromagnet or would it be better to make a seperate power supply just for the Field Coil? My idea is to put this speaker into its own cabinet with the power supply and then just run the audio signal out of the guitar amp to the cabinet as if it were a permanent magnet speaker. Other than that, my only concern is how do I ascertain how much DC voltage it needs for its optimal efficiency. Unfortunately, I don't have a variable high voltage supply that I can use to tweak it but, I have a bunch of step-up Transformers ranging from 200v up to 700v or so that I can use. The power transformer that came off of the organ's amplifier is a 300-0-300 vct which was what it used to power the Field Coil. I'm really just trying to figure out how to give it what it wants and avoid giving it too much or too little. Thanks again!
I love electronics!...just not quite enough to do the work in college, unfortunately. My goal is to buy some vintage field coil speakers from eBay, and construct some top quality sealed enclosures made of MDF and wood for them. I need to figure out how much voltage a field coil speaker needs (I’m suspect it varies from model to model). The end goal is to take a 1940s or ‘50s era speaker which would otherwise be discarded and get it to sound as good as possible.
Sounds like a fun project, MusicStudent1. Yes, you’ll need to do your homework on the speaker you use to determine the volts required and amps drawn by the field coil. Then, you can locate a suitable DC power supply. Also be mindful of the voice coil’s impedance as you’ll want to make sure your amp is a suitable match. I’ve never built a speaker cabinet, but have always been interested in the process. There’s a lot to consider, and again, you’ll want to do research to determine if the speaker you choose will work best in a sealed enclosure or one with a port or other opening. You may also want to augment it with a high frequency driver which would require a crossover. There are many books and online resources available discussing speaker design. The internal volume and damping materials used can be critical to get good sound as resonance needs to be considered. Good luck with the project and keep us updated with your progress.
@@FluxCondenser , the idea is to take a device, like a loudspeaker, and take it beyond it's intended use. I did a little prototype project this summer with $4.00 speakers, an amp, and a wine storage box. It has ridiculously deep bass when I play those subwoofer demos on it. ruclips.net/video/h4bYGBB9sNA/видео.html ruclips.net/video/5vuAaLebMc0/видео.html An electrical engineer friend of mine attended an audio lecture in college and relayed that in a nutshell...the bigger the enclosure the better and the bigger the baffle the better. My enclosures are going to be sealed and huge...it's going to be an experiment. Stand by!
Great video, thanks for sharing! Subbed. Please note that modern speakers do still use electromagnets. More accurately, modern speakers no longer use electromagnets for the field coil, but the voice coil is an electromagnet and thus vibrates against the permanent magnet when power is modulated through the voice coil.
Thanks, Samy, appreciate the sub and excellent comment. Yes, in this video I didn’t want to get ahead of myself and focused only on the field coil. The voice coil is described in a later video in the series called, “How does a speaker work...” There, the function of the voice coil as an electromagnet is discussed. ruclips.net/video/TYxfdg6yfOk/видео.html
@@FluxCondenser Ahh, very cool!
Your explanation or contention is quite weird. A moving coil speaker (or a microphone) is a transducer, which means it converts energy in one form to the other. A speaker converts electrical energy (power) into acoustic energy.
If both the field and the armature happen to be of permanent magnets there won't be anything happening.
In a static magnetic field if a conductor moves a current would be induced; this is a dynamo. In the same static magnetic field a current is passed in a conductor the conductor would move. Remember the Fleming's left hand rule for the motor and the right hand rule for the dynamo.
In the beginning people had used electromagnet for providing the magnetic field in which the armature, the voice coil of the speaker moved.
The added feature is that it offered the other important function of chocking the AC ripples in the rectified power to the radio.
The people of those days had real sense in doing something. We should be able to appreciate it.
Now a days it's not needed because of the availability of very strong permanent magnets, the Neodymium alloy being the strongest till now.
What specific explanation or contention is weird? Your explanation just rehashes what’s been described in my videos.
Thanks for the video! I have a question if I may ask... I have a big, and very heavy, 12" Field Coil speaker that came out of an old Hammond Organ and I want to use it with a Guitar amplifier. I'm sure every Field Coil is different but, would I generally use the B+ coming off the Guitar amplifier to power the electromagnet or would it be better to make a seperate power supply just for the Field Coil? My idea is to put this speaker into its own cabinet with the power supply and then just run the audio signal out of the guitar amp to the cabinet as if it were a permanent magnet speaker. Other than that, my only concern is how do I ascertain how much DC voltage it needs for its optimal efficiency. Unfortunately, I don't have a variable high voltage supply that I can use to tweak it but, I have a bunch of step-up Transformers ranging from 200v up to 700v or so that I can use. The power transformer that came off of the organ's amplifier is a 300-0-300 vct which was what it used to power the Field Coil. I'm really just trying to figure out how to give it what it wants and avoid giving it too much or too little. Thanks again!
This is good stuff and well presented
I love electronics!...just not quite enough to do the work in college, unfortunately. My goal is to buy some vintage field coil speakers from eBay, and construct some top quality sealed enclosures made of MDF and wood for them. I need to figure out how much voltage a field coil speaker needs (I’m suspect it varies from model to model). The end goal is to take a 1940s or ‘50s era speaker which would otherwise be discarded and get it to sound as good as possible.
Sounds like a fun project, MusicStudent1. Yes, you’ll need to do your homework on the speaker you use to determine the volts required and amps drawn by the field coil. Then, you can locate a suitable DC power supply. Also be mindful of the voice coil’s impedance as you’ll want to make sure your amp is a suitable match. I’ve never built a speaker cabinet, but have always been interested in the process. There’s a lot to consider, and again, you’ll want to do research to determine if the speaker you choose will work best in a sealed enclosure or one with a port or other opening. You may also want to augment it with a high frequency driver which would require a crossover. There are many books and online resources available discussing speaker design. The internal volume and damping materials used can be critical to get good sound as resonance needs to be considered. Good luck with the project and keep us updated with your progress.
@@FluxCondenser , the idea is to take a device, like a loudspeaker, and take it beyond it's intended use. I did a little prototype project this summer with $4.00 speakers, an amp, and a wine storage box. It has ridiculously deep bass when I play those subwoofer demos on it.
ruclips.net/video/h4bYGBB9sNA/видео.html
ruclips.net/video/5vuAaLebMc0/видео.html
An electrical engineer friend of mine attended an audio lecture in college and relayed that in a nutshell...the bigger the enclosure the better and the bigger the baffle the better. My enclosures are going to be sealed and huge...it's going to be an experiment. Stand by!
Sir bush tr122 redio s oudio filter choke pawer and speaker s om?
Field coil speaker driver