The end result is really impressive for how rudimentary it is Really surprising how basic the fundamentals of parts of our lives are that are then just fine tuned by experts
That's a really good point - getting a basic version of common household gadgets is pretty easy. But I'm constantly stunned how complex it can be to refine them!
A few suggestions: 1). Those thumping noises after P sounds are because you don't have a pop filter, so the bursts of air from plosives are hitting the microphone and making it go thump. 2). This is a dynamic microphone, which if I recall, tend to want/need their own preamp before your computer's sound card has at it. This might be part of why the noise is so bad, so maybe a simple op-amp circuit to boost the signal before sending it off would help things.
Ah that makes a lot of sense, I'd love to try some kind of preamp then. Cheers for the heads up! The pop filter is probably the easiest problem to fix. Thanks for the suggestions 😃
@@JamiesBrickJams And i just want to add that the weight of the membrane is absolutely critical to the high frequency sound , also winding the coil as close as possible to the edge of the magnet will make the microphone a lot more sensitive , and a preamp board will help so much too :) !
@@davidfrancois2764 very true! I tried many variations to get that coil inside the magnet and as close as possible but really struggled 😅 Will certainly see what's possible with some other membrane materials! Cheers again 😁
maybe even a single jfet could give you enough amplification. But usually that is used for electret microphones. Those use change of capacitance, instead of induction. edit: for electret microphones, you literally need no extra components, only the JFET, but coils conduct well, so this may need a more complicated circuit. A two battery powered OPAMP circuit would be much easier to build and operate (two batteries, one opamp, two resistors, plus one extra capacitor or resistor on the output).
honestly this feels perfect for a horror recording format, the audio sounds old and dated perfect for something like old interview tapes or documentation recordings.
A lot of the low frequency noise you are getting is from your desk being touched and because you have no pop filter. The desk vibrations could be solved by isolating the part that holds the membrane and coil with some more rubber bands like the ones you used for the membrane. It also might be worth looking into using a preamp of some kind as they can help reduce noise and filter out frequencies you don't want in addition to increasing the signal strength.
Some fantastic advice here, thanks for sharing! A pop filter is definitely an easy addition, and more isolation I think should be pretty straightforward too. Will need to do a bit more research into a pre amp though. I experimented with various transformers and they all added various odd buzzing noises. But thanks for the heads up - I'll look into some kind of filtering!
@@JamiesBrickJamstransformers might not be the best idea, perhaps digital preamps could be good (im not sure, but "OP-Amp" might be the electric ic's name..
you almost certainly want to pre-amplify the signal to make it usable for your PC, also, it could use a low-pass filter to reduce high-frequency noise.
Most of the suggestions I see in the comments look to be correct. Since in a dynamic microphone, the induced voltage on the coil is proportional to the change in magnetic flux, you may be able to increase the output level by having your coils closer to the magnet (i.e. nearly touching the "outside corner" of your ring magnets) -- if you search for magnetic field diagrams, your aim should be for the coils to cross over as many of the lines as possible during movement to get maximum induction. Using magnets without holes in the centre will increase the magnetic field strength, too. As other people have said, the dongle you are using is likely designed for a microphone with an impedance on the order of 1000 Ohms, so you need a preamp which will both amplify the voltage to a suitable level and provide an input impedance more closely matched to your coil to prevent signal degradation from power loss. I imagine it would be rather difficult to find something suitable at a reasonable price -- the other alternative is to try a DIY preamp with op-amps, resistors and some other discrete components - certainly possible on a breadboard given enough time and perseverance. The frequency response you're getting will in part be due to impedance mismatched power losses, but is probably mostly from the material of your membrane. Typically microphone membranes are extremely thin in order to reduce their mass for any reasonable high-frequency response, and the LEGO you use to mount the coil will be contributing a damping effect from the extra mass. The best suggestion I can make would be to use something like tracing paper to try and reduce the mass of the membrane as much as possible. One other thing -- you may want to twist your wires together. It doesn't sound like you're getting much EM interference, but twisted pair is an easy way to reject a lot of environmental noise and it should reduce the power losses a little too. Good luck!
Fantastic advice, thanks so much for taking the time to post! Really appreciate details like this. I think you're definitely right about using a decent pre amp. To be honest I don't know much about them, but if I can find an affordable solution, I'll definitely give that a try. Other membranes too will be interesting to experiment. I'm still holding out hope my ribbon microphone might work out. Or perhaps a capacitative membrane. Cheers again for the advice! 🙏
I like how it sounds like an old carbon microphone. These audio components out of Lego are really cool! You could try and make a record player next that would be awesome
Thanks a lot! Haha funny you mention that - I've actually been toying with the idea of a record player. It's certainly something I'm seriously considering!
I am not an audio expert, but i may suggest you to focus on making the membrane much more thinner and lighter, i'm quite shure that way it will work better since the noise you hear is not because of the microphone itself but because the signal it produces is so low that the computer has to amplify it but it will also amplify the noise. Btw great work and i really love your videos!
Thanks a lot, appreciate it! And yeah you're totally right, I keep having to boost the signal on the recording which also boosts the noise. I'll certainly try some different membranes. Perhaps also delivering some power from the PC so that I can boost the signal before it hits the PC
You might be able to get similar with just plastic wrap yea? The reason you'd want something light is bc sound is just a difference in pressure / pressure wave, which means you have a force applied over each area of the membrane, so less dense and thick that membrane the more movement that force generates, which means more voltage
@jamievancoppenhagen the actual membrane inside a lot of microphones is just thin plastic, like you might get from certain plastic bottles, or the cover of folders for documents. Just needs to be thin, but not deform under its own weight. Then the frequency response will be wider and less bassy probably.
You need a thinner membrane and a not so stiff suspension. Also, the wheel the cardboard and the magnet are attached to adds too much weight and dampens the whole membrane. More mass needs more force to start moving so try to get that as low as possible. As others have said, a pre-amp is necessary, there are simple op amp circuits out there. the coil should be inside the magnet or around it, as the magnetic field is the greatest there and thus should increase the voltage output.
I suggest putting one of those magnet clips that used to be used on old USB cables. I tried doing that for an antenna and it seemed to reduce some of the static in audio, so I wonder if it can do the same for a microphone.
To produce larger signal level, you need few things: First, the magnetic circuit should be as short as possible - the coil has to be very close to the magnet(s), where the magnetic field is strongest. Second, the coil has to have sufficient amount of turns - voltage generated is proportional to number of turns. Third, the membrane has to be very lightweight so the acoustic pressure moves it easily.
I think a smaller, lighter diaphragm could give you higher frequencies. If your diaphragm is big and heavy, you essentially get a natural low pass filter, because more mass doesn't like to move as much, and the bigger area also gives you more air resistance.
Dynamic mics work really well with really loud sources like orchestras or bass/guitar amps, and for the latter character is probably more important than accuracy
I wear a pair of decent audiophile headphones and something about your last mic was occasionally producing the DEEPEST bass i've ever heard. I think it was whenever you would touch the desk? Felt like my brain was going to vibrate out lol
Haha oh man my apologies 😅 I totally know what you mean - I was also using some decent over ear Sony headphones and felt my brain shaking during those pops! I debated cutting them out but figured I'd rather leave it un-doctored. RIP your poor ears
For a dynamic mic like this you won't need any kind of bias voltage, only electret and capacitive mics need a bias voltage, however you could really use a decent pre-amp because the one in your dongle is not designed to be used with such a high impedance low output microphone
I actually did try that using various amplifiers - even a homemade transformer! But unfortunately they all created a buzzing noise. But that's still a great idea, and I'll continue to work on them - thanks. They'll certainly be needed for the ribbon microphone to work properly
I feel like what probably helped the most with the last iteration was physical closeness of the magnet and coil, since the field strength falls off with the square of the distance iirc, having it close makes the signal a lot stronger. This is really cool tho
Others have mentioned some important things, a pre-amp is going to be a necessity. Some design tips as well, if you can make the membrane lighter and thinner without compromising it's strength much, I would absolutely investigate that. instead of elastics, try something like fishing wire to suspend the diaphragm, you actually don't want things to be too "bouncy" and I believe fishing wire may be the perfect blend of flexible and stiff for this application. I think your final design of having the coil near the middle of the magnet was really good, consider the direction of the field lines vs the direction you're wanting to induce a current. You generally want the magnetic field to be moving orthogonal to the direction you want the coil to generate current, which is perfect in your final setup, you may want to experiment with sinking the coil in further or making the coil longer, passing through more of the center of the magnet.
You should definitely use a pre-amplifier. They are used in dynamic microphones (the one you have). It will help with the loudness. Also add a popfilter so you don't blow into the mic. You can maybe move the coil inside the magnet area. You can also try making another coil and connecting them in series (make sure both of the coils are twisted the sane way, for example if the first coil is twisted clockwise, the other one can't be anti-clockwise or else the coils would work against each other and there would be no sound). You can make a box around it with only a wall missing on the front of the microphone and add some padding onto the walls to make it onky pick up your voice and not the surroundings. You can maybe even try to makr a bigger membrane to not make it as tinny and bring more bass. You can then cut the membrane to perfection. Hope any of these tips will help you!
Oooh hooking up a couple in series would have been a cool idea! I was struggling to find Lego pieces that fit snugly inside the magnet, but another coil in front in series would have been an easy way of boosting the signal. And I'm sure you're right about a pre amp. I'm seeing if I can find an affordable solution there. Cheers for the advice!
I know it's weird to ask (and I haven't had time to finish the full video), but could you do a mini-tutorial or whatever on how to make a 'bad' microphone with this? I want to hear Edison wax cylinder quality sound, y'know.
- 4:33, you need to have shielded wires (wires insulated by a first coasting, metal mesh or film, and then a thicker final coating, creating what resembles a speaker or headphone wire at the least). Also, you would need a pre-amplifier to boost the initial signal, ensuring that that will both be shielded and offer a unclipped, undistorted, and still loud enough signal to at least be decently recognisable. - 4:39, thinner wire tends to catch more residual signal and for higher voltage and lower current, thicker being for lower voltage yet higher current. - 8:09, the signal is clearer due to the placement of the coil within a magnet, being closer and of more effect when generating Eddie currents through the coil. just three helpful tips :>
a thinner membrane like cellophane or a balloon stretched over a ring may give it more response as it will warp easier than a thick material, taking the higher frequencies
If you put a mesh over it it might help a little, modern microphones have a ring around them tightly packing a mesh to it. Dont know if its possible with legos, but just a heads up!
Electronics hobbyist here, I graduated the german equivalent of highschool this year and will start studying electrical engineering soon and am quite invested in it already. One thing that would most definitely improve the sound quality is adding a pre amp. Capturing audio will always add noise and when you amplify the audio in post you also amplify the noise floor, this is called signal to noise ratio and by making the input signal louder aka adding a pre amp you can increase the signal to noise ratio and thus decrease the noise in your recording. This would most likely remove the need for noise reduction in post. Something else I am not very familiar with, but would look into, is the resonance frequency of the membrane, that being the frequency the membrane naturally tries to vibrate at and thus where the microphone is the most sensitive. The resonance frequency of you designs is probably pretty low, meaning it picks up low frequencies well but everything else not so much. Again I am not very familiar with the mechanical side of things so I am not sure how to solve this best.
Howdy! And cheers for your comment - that was very helpful 😁 I'm sure you're right about a better preamp. That audio dongle I was using probably wasn't doing much of anything. Will certainly give that a try in a future version! Also you're totally right about the cardboard membrane - it's likely dampening things an awful lot. Here's hoping the ribbon microphone will do a better job 🤞🤞
Thanks! And you're totally right, in this case I was really debating turning off all music. After trying with and without music, I personally didn't think it distorted the audio coming from the mic, but definitely appreciate that it can be distracting. Will bear that in mind in future - thanks for the feedback!
Put a Metal Housing around the coil and the magnet. I could bet, that there is a significant amount of electromagnetic background noise. (that should improve some of the static)
Perhaps you might want to try making a condenser microphone next? It's basically what you've already made, except you use a conductive membrane (like a sheet of copper foil), and a conductive backplane (again, copper foil) instead of a magnet. This creates a capacitor which you can charge with a constant DC power source (a battery). As the membrane moves, the capacitance will change, which can then be detected by putting a resistor in series and taking the voltage over it as the signal. In theory it should give a much better frequency response, as you can use a much lighter membrane (no coil of wire in the center).
That's a really cool idea, thanks for suggesting! I as vaguely aware of them, but haven't done much research into how they work exactly. Your description sounds reasonably straightforward. Cheers for the tip - I'll certainly look into it some more!
A few suggestions: 1. Try a much lighter or more flexible membrane 2 Make the coil fit inside the magnet or surrounding the magnet (You want the coil to vibrate between the poles) 3. Use a shielded cable for as long as possible. Connect the microphone between the ring and the tip pins. Sleeve is the ground. 4. If you add a pre-amp, you want something like an electric guitar pre-amp, not a microphone one.
All fantastic suggestions, thanks for sharing them! I tried pretty hard to get that coil inside the magnet but really struggled to find the flight fit. But that would have been ideal. Certainly for a future version I'd like to try a better preamp and better membrane materials!
Tho I do not entirely know how a microphone's internals look, I do have at least one we could take apart to see what is inside and try to recreate it with Legos.
I might be a little late and off on my understanding of audio/vibration frequencies but, for what I understand if you were to use a large rectangle diaphragm and offset your coil with a 1/3-2/3 on both axis it should capture more frequencies than a large circle. I liked seeing you distance the magnets and coil from the diaphragm though, good idea!
Ah thanks, I've no idea if that was a good idea or not, but it seemed to work ok. That's an interesting idea to offset the coil - will need to run a few more tests I think!
Great video! You might try using a thinner lighter membrane. A heavier membrane should vibrate more at lower frequencies and a lighter membrane at higher frequencies. Think about how fast you can shake a beach ball vs how fast you can shake a bowling ball. Maybe a balloon stretched over a frame or something similar would work?
Maybe a thinner membrane and a microphone preaamp with a low noise floor? I have combined microphones myself, and wathching this made me want to design my own from scratch! Thank you so much, very inspirering!! :D
A lot of good mics will often have signal processing using one close mic and one far away mic, then using a differential amplifier to only give you the difference, idealy that'd be your voice. Also various different mechanical filters can be applied if you feel like doing it physically rather than with software - 3rd Year Engineering Love what you're doing here, it's a fun watch
Thanks a lot! Glad it's still interesting to an engineer, as basic as it is. I'll certainly give an amp a try on the next version. Would love to learn more about physical amps though too. I like the idea of minimal 'assistance'
So I know I'm a little late to the game and I also am not an audiophile or engineer. BUT! Maybe a thinner membrane to allow more minute vibrations? Maybe parchment paper? The issue then becomes suspending the coils in the medium (membrane) without the weight causing distortion or tearing. Once again, I have no working knowledge or qualifications.
I've tried a few! Softer seems to introduce more bass and higher frequency response drops. But I'm sure there's still loads of experimenting to do to find the optimal balance
Years of 12v audio experience (car audio). The most important thing to remember is your membranes weight/surface area ratio. For input, you want as light as possible while covering as much surface area as possible. Make the membrane out of something thin, light, and durable (think like a piece of one of those clear notebook dividers or something) keep it suspended and about the same size as your original. Next, make your coils tighter. Go down on your inner diameter. Should allow you many more turns, especially with that thin stuff. Your goal is to produce the highest amount of fluctuation, regardless of the actual voltage. For example a low of 1v and a high of 10v is better for input than let's say a low of 5v and a high of 12v. That 2v difference isn't worth the range of audio you will get with the lower voltages. Hope all that makes sense. And my voltage #s are from out of thin air, so take it as an example.
That totally makes sense, really appreciate you sharing these recommendations! For a future version I'll certainly try a thin coil with many windings. As much as I hate dealing with thin wire, I might even go thinner than 38 gauge to get those windings up 😬 Cheers!
An over ear design would sertanly be the easiest way to go, As the speaker it's elf can be much larger. If you wanted to make it an extra challenge instead of two drivers you could have 4 (2 for highs and 2 for lows) placing the lows in front closer to the ear, as they would be most likely much large than the highs.
Use a nylon string for the suspension of the coil, or use a nylon stalking cut out. The nylon will help pick up more vibrations and, in turn, make the audio clearer. If you use nylon string then the audio will be sharper but also more suseptible to that tinny noise where as the nylon fabric from most thin nylon stalkings are perfect for both catching audio and dampening any high pitched audio. Also, you need to align your coil and magnet. The coil keeps getting too close to the magnet, which is creating that old-school microphone effect. You don't really want the coil to wiggle around so much as you want it to move back and forth through the magnet. Lastly, a few more dampeners from the table to the magnet and coil will help make the background buzzing stop. Good luck.✌️
Is there a reason why you opted to use a TS connection as opposed to a TRS? If I remember correctly, TRS tend to have cleaner sound due to phase cancelation, or something like that. Been a while since I brushed up on that side of audio, since I’m more of a studio, mix, master, and post engineer. Really interested to see how you build a ribbon mic. They have a nice sound to them and a pretty cool science all things considered. Also, if you haven’t done it yet, I’d love to see you recreate a plate style reverb using lego. Who knows, it could become the new thing within the music world, lol.
There sure is a reason - I found a cheap pack of 10 😁 I butchered a bunch of other cables, including TRS, but they all sounded the same to me, so I just went with TS cause it looked cleaner. Terrible reason I know! But thanks for reminding me - really should try a few other cables with the improved mics. Great idea RE the reverb - I only recently heard of it, but it sounds really cool!
I'm curious how something like parchment paper or a stretched balloon/rubber glove for a membrane would sound. I assumed the cardstock sounded the way it did because it was too thick, but I'm not sure
The end result is like an actually usable microphone with quality genuinely comparable to really old professional microphones used in radio broadcasts, which is insane. A big part of that is probably the noise cancellation, but regardless considering how much of a limitation you have, that thing has no right to be as good as it is.
Aw thanks a bunch, appreciate your comment 😁 There's definitely massive room for improvement, but I was just as surprised to see just how easy a basic microphone really is! Certainly easy for anyone to make in an afternoon with minimal parts
such a cool concept, I don't really know eny thing about microphones, but that last one actually works pretty well it just has a old sound to it, keep up your amazing work!
08:00 There you have it. Now you can understand why in the 20s and 30s people talked funny on the radio! Because microphones just weren't as good then. You can hear high-pitched voices much more easily than bass. This is also why the transatlantic accent was so popular during the time; it was easier to understand dialog over the radio :)
Love the audio series so far! ❤ Anyway, i have a little bit of experience with microphones. There are tons of different kinds and technologies you should read yourself into but these are the tips that i got, that may help. First i think experimenting with ribbon or string microphones is a step forward but you can also achieve good results with membrane microphones. As you saw a good and big but stiff membrane should get the job done, atleast i believe so, because you want to have a good range of frequency and so far your last design sounded good but i think there were not enough low frequencies and it therefore sounded like an old iphone speaker. And stiff because you want to get rid of afterbounce and background noises of course. I beliefe that helps I think you should also cover the microphone with a fine piece of cloth! Especially at the front. That should help with the background noises aswell and also act as a pop filter, so you don't get those high bass pops everythime, especially when you say the letter P in any sentence. And it may help looking at non self powered microphones, where your device, like your PC gives power to the microphone, like via USB signal and the frequency waves get rectified onto the power signal, so that the signal frequency is modulated to contain the audio, which should give you the ability to justify the volume of the microphone. Hope that helps
Woah thanks for replying with so much detail - really appreciate you taking the time! I'd love to experiment with a membrane microphone. By that, do you mean like a condenser microphone? A pop filter is certainly an easy fix I can add to it! And agree, I think it makes sense to deliver power to boost the signal. To be honest, I'm not too familiar with how that circuitry works, but I'm sure it's relatively straightforward - will look into it some more. Cheers!
@@JamiesBrickJams Yes that is the type of micrphone that i was talking about. Allthough Ribbon or String microphones are generally used for radio station etc., atleast i heard so, condenser microphones are usually all around us, like normal Tablestand microphones. There also exists a type of microphone with large Membranes, which usually are these weird conference microphones, you see in conference rooms a lot. These that look like small ufo's for example. I think that is as far as my knowledge goes.
Try to use baking paper, idk if that will help but it's thin and flexible would work for a membrain or even like a disposable rubber clove maybe a balloon
The end result is really impressive for how rudimentary it is
Really surprising how basic the fundamentals of parts of our lives are that are then just fine tuned by experts
That's a really good point - getting a basic version of common household gadgets is pretty easy. But I'm constantly stunned how complex it can be to refine them!
As an audio nerd and lego enthusiast, i absolutely love this series of audio components made from lego
Aw well glad it's hitting the mark for some folks like yourself 😁 Cheers! 🙏
can relate
I love how the last mic sounds like the one they used waaay back in the past, it's make it nostalgic in a way 😀
Cheers 😁 Weird how lack of bass makes it sound old!
@@JamiesBrickJams I was half expecting to hear it play back in a Transatlantic accent
Looks like one too, likely not a coincidence.
A few suggestions:
1). Those thumping noises after P sounds are because you don't have a pop filter, so the bursts of air from plosives are hitting the microphone and making it go thump.
2). This is a dynamic microphone, which if I recall, tend to want/need their own preamp before your computer's sound card has at it. This might be part of why the noise is so bad, so maybe a simple op-amp circuit to boost the signal before sending it off would help things.
Ah that makes a lot of sense, I'd love to try some kind of preamp then. Cheers for the heads up! The pop filter is probably the easiest problem to fix. Thanks for the suggestions 😃
@@JamiesBrickJams
And i just want to add that the weight of the membrane is absolutely critical to the high frequency sound , also winding the coil as close as possible to the edge of the magnet will make the microphone a lot more sensitive , and a preamp board will help so much too :) !
@@davidfrancois2764 very true! I tried many variations to get that coil inside the magnet and as close as possible but really struggled 😅 Will certainly see what's possible with some other membrane materials! Cheers again 😁
maybe even a single jfet could give you enough amplification. But usually that is used for electret microphones. Those use change of capacitance, instead of induction.
edit: for electret microphones, you literally need no extra components, only the JFET, but coils conduct well, so this may need a more complicated circuit. A two battery powered OPAMP circuit would be much easier to build and operate (two batteries, one opamp, two resistors, plus one extra capacitor or resistor on the output).
Ribbon type microphones also needs an preamp. And try to find audio transformer for microphones, like replacement part for Shure SM57
honestly this feels perfect for a horror recording format, the audio sounds old and dated perfect for something like old interview tapes or documentation recordings.
Haha that's a really fun concept 😄
Makes sense considering hes almost engineering it from the beginning with very limited resources. Same as the first microphones and recording devices
apocalyptic fallout mic the villain speaks into to monologue to the protag vibes
it's insane out incredibly simple speakers and microphones are
True!
Insted of post-processing you can go analog way.
A lot of the low frequency noise you are getting is from your desk being touched and because you have no pop filter. The desk vibrations could be solved by isolating the part that holds the membrane and coil with some more rubber bands like the ones you used for the membrane. It also might be worth looking into using a preamp of some kind as they can help reduce noise and filter out frequencies you don't want in addition to increasing the signal strength.
Some fantastic advice here, thanks for sharing! A pop filter is definitely an easy addition, and more isolation I think should be pretty straightforward too. Will need to do a bit more research into a pre amp though. I experimented with various transformers and they all added various odd buzzing noises. But thanks for the heads up - I'll look into some kind of filtering!
@@JamiesBrickJamstransformers might not be the best idea, perhaps digital preamps could be good (im not sure, but "OP-Amp" might be the electric ic's name..
@@JamiesBrickJams I'd recommend using a resistor too
@TheCustomFHD why do I recognize you I feel like we used to talk on discord
@@Idontknow4 possible. Any server names that come to mind?
you almost certainly want to pre-amplify the signal to make it usable for your PC, also, it could use a low-pass filter to reduce high-frequency noise.
That would have been a really good idea, cheers for the heads up - will need to figure out how a basic filter like that works!
After 22 years I’ve finally discovered how a microphone works, and it took LEGO to do it. Thank you for this wonderful video!
Aw well I'm delighted this helped to break it down 😀
Most of the suggestions I see in the comments look to be correct.
Since in a dynamic microphone, the induced voltage on the coil is proportional to the change in magnetic flux, you may be able to increase the output level by having your coils closer to the magnet (i.e. nearly touching the "outside corner" of your ring magnets) -- if you search for magnetic field diagrams, your aim should be for the coils to cross over as many of the lines as possible during movement to get maximum induction. Using magnets without holes in the centre will increase the magnetic field strength, too.
As other people have said, the dongle you are using is likely designed for a microphone with an impedance on the order of 1000 Ohms, so you need a preamp which will both amplify the voltage to a suitable level and provide an input impedance more closely matched to your coil to prevent signal degradation from power loss.
I imagine it would be rather difficult to find something suitable at a reasonable price -- the other alternative is to try a DIY preamp with op-amps, resistors and some other discrete components - certainly possible on a breadboard given enough time and perseverance.
The frequency response you're getting will in part be due to impedance mismatched power losses, but is probably mostly from the material of your membrane. Typically microphone membranes are extremely thin in order to reduce their mass for any reasonable high-frequency response, and the LEGO you use to mount the coil will be contributing a damping effect from the extra mass. The best suggestion I can make would be to use something like tracing paper to try and reduce the mass of the membrane as much as possible.
One other thing -- you may want to twist your wires together. It doesn't sound like you're getting much EM interference, but twisted pair is an easy way to reject a lot of environmental noise and it should reduce the power losses a little too.
Good luck!
Fantastic advice, thanks so much for taking the time to post! Really appreciate details like this. I think you're definitely right about using a decent pre amp. To be honest I don't know much about them, but if I can find an affordable solution, I'll definitely give that a try. Other membranes too will be interesting to experiment. I'm still holding out hope my ribbon microphone might work out. Or perhaps a capacitative membrane. Cheers again for the advice! 🙏
I like how it sounds like an old carbon microphone. These audio components out of Lego are really cool! You could try and make a record player next that would be awesome
Thanks a lot! Haha funny you mention that - I've actually been toying with the idea of a record player. It's certainly something I'm seriously considering!
I am not an audio expert, but i may suggest you to focus on making the membrane much more thinner and lighter, i'm quite shure that way it will work better since the noise you hear is not because of the microphone itself but because the signal it produces is so low that the computer has to amplify it but it will also amplify the noise. Btw great work and i really love your videos!
Thanks a lot, appreciate it! And yeah you're totally right, I keep having to boost the signal on the recording which also boosts the noise. I'll certainly try some different membranes. Perhaps also delivering some power from the PC so that I can boost the signal before it hits the PC
@@JamiesBrickJams What about a cut open and stretched rubber glove?
You might be able to get similar with just plastic wrap yea?
The reason you'd want something light is bc sound is just a difference in pressure / pressure wave, which means you have a force applied over each area of the membrane, so less dense and thick that membrane the more movement that force generates, which means more voltage
@jamievancoppenhagen the actual membrane inside a lot of microphones is just thin plastic, like you might get from certain plastic bottles, or the cover of folders for documents. Just needs to be thin, but not deform under its own weight. Then the frequency response will be wider and less bassy probably.
Are you sHure you're not an audio expert ?😅
You need a thinner membrane and a not so stiff suspension. Also, the wheel the cardboard and the magnet are attached to adds too much weight and dampens the whole membrane.
More mass needs more force to start moving so try to get that as low as possible. As others have said, a pre-amp is necessary, there are simple op amp circuits out there.
the coil should be inside the magnet or around it, as the magnetic field is the greatest there and thus should increase the voltage output.
We makin it to the antique radio studio with this one
I suggest putting one of those magnet clips that used to be used on old USB cables. I tried doing that for an antenna and it seemed to reduce some of the static in audio, so I wonder if it can do the same for a microphone.
That's really interesting, I'd love to find any way of reducing that noise!
I love the last microphone you made. You sounds like your an old timey radio announcer
Thanks a lot 🙏 Yeah it does have that sort of old timey sound profile a bit!
i think making the membrane lighter and be suspended on weaker rubber bands might make it better
So something like waxed paper might work
It sounds like a radio recording from the 30's. Love these.
Ha yeah it does have a bit of an old school sound to it! Cheers 😁🙏
It sounds spot-on like an old 1930's radio mic, just needs something to boost the signal and perhaps a pop-filter.
Too right you are - great suggestions! And thanks 😁
Your videos are so professionally edited and made you're going to grow so much.
Aw shucks, thanks a lot - I appreciate it!
To produce larger signal level, you need few things: First, the magnetic circuit should be as short as possible - the coil has to be very close to the magnet(s), where the magnetic field is strongest. Second, the coil has to have sufficient amount of turns - voltage generated is proportional to number of turns. Third, the membrane has to be very lightweight so the acoustic pressure moves it easily.
sounds real vintage (maybe it could be used that way)
Ha you're right, it does have a hint of those old timey recordings
I think a smaller, lighter diaphragm could give you higher frequencies. If your diaphragm is big and heavy, you essentially get a natural low pass filter, because more mass doesn't like to move as much, and the bigger area also gives you more air resistance.
The fact that you were able to record using the microphone you made, and once you switched to only that I was still able to understand it was insane.
Thanks a lot 😁 I wasn't sure folks would be able to actually hear what I was saying at the end, but glad it came through ok (as messy as it sounds!)
I was prepared to need subtitles but no need.
Can you hook up your lego microphone in one room to the lego speakers in another room? I'd like to hear a lego intercom
That's a really cool idea! I see no reason why that shouldn't be possible - might give that a try someday. Cheers for the suggestion 😁
@@JamiesBrickJamscould be good for a YT short vid (y'know, the shorts feature)
Dynamic mics work really well with really loud sources like orchestras or bass/guitar amps, and for the latter character is probably more important than accuracy
sounds like an old radio which is very interesting
Thanks 😁
It kinda looks like an old carbon microphone
It’s like a ww2 mic and makes your voice sound like the old narrating voices
Haha it does a bit! Though I don't think anyone wants to hear me narrating anything with this 😂
SO LIKE THIS ONE TIME MATE
0:59
As a Dankpods subscriber, this IS roughly the quality that I am used to.
Ayyyy 👉😄
I love how it sounds old-timey
I would suggest surrounding the microphone with foam and using a bit of a high pass filter to reduce both background noise and that low end rumble
He used the mic in the video recording. The madlad
I wear a pair of decent audiophile headphones and something about your last mic was occasionally producing the DEEPEST bass i've ever heard. I think it was whenever you would touch the desk? Felt like my brain was going to vibrate out lol
Haha oh man my apologies 😅 I totally know what you mean - I was also using some decent over ear Sony headphones and felt my brain shaking during those pops! I debated cutting them out but figured I'd rather leave it un-doctored. RIP your poor ears
For a dynamic mic like this you won't need any kind of bias voltage, only electret and capacitive mics need a bias voltage, however you could really use a decent pre-amp because the one in your dongle is not designed to be used with such a high impedance low output microphone
You could try an microphone amplifier that will make it louder and maybe even clearer.
I actually did try that using various amplifiers - even a homemade transformer! But unfortunately they all created a buzzing noise. But that's still a great idea, and I'll continue to work on them - thanks. They'll certainly be needed for the ribbon microphone to work properly
you would probably need more turns for louder audio, could maybe use a preamplifier and to remove the noise some copper tape around the mic
I feel like what probably helped the most with the last iteration was physical closeness of the magnet and coil, since the field strength falls off with the square of the distance iirc, having it close makes the signal a lot stronger. This is really cool tho
The culmination of this series needs to be recording an album on all Lego instruments, using all Lego equipment
Haha that would be amazing, what a cool idea! 💡
This reminds me of the very early stages of microphone from the 1920s
It does sound like one of those old relics 😁
I love the scarlet fire. I need to make this speaker/mic and use the mojo on it
Haha that's the dream 😂
Others have mentioned some important things, a pre-amp is going to be a necessity. Some design tips as well, if you can make the membrane lighter and thinner without compromising it's strength much, I would absolutely investigate that. instead of elastics, try something like fishing wire to suspend the diaphragm, you actually don't want things to be too "bouncy" and I believe fishing wire may be the perfect blend of flexible and stiff for this application.
I think your final design of having the coil near the middle of the magnet was really good, consider the direction of the field lines vs the direction you're wanting to induce a current. You generally want the magnetic field to be moving orthogonal to the direction you want the coil to generate current, which is perfect in your final setup, you may want to experiment with sinking the coil in further or making the coil longer, passing through more of the center of the magnet.
have a look at diy perks' diy microphone video. it's not only a great video but also very informative.
having that said, i really love your videos too
Thanks for the recommendation - I'll definitely give his video a look. I love his channel! ♥️
You should definitely use a pre-amplifier. They are used in dynamic microphones (the one you have). It will help with the loudness. Also add a popfilter so you don't blow into the mic. You can maybe move the coil inside the magnet area. You can also try making another coil and connecting them in series (make sure both of the coils are twisted the sane way, for example if the first coil is twisted clockwise, the other one can't be anti-clockwise or else the coils would work against each other and there would be no sound). You can make a box around it with only a wall missing on the front of the microphone and add some padding onto the walls to make it onky pick up your voice and not the surroundings. You can maybe even try to makr a bigger membrane to not make it as tinny and bring more bass. You can then cut the membrane to perfection.
Hope any of these tips will help you!
Oooh hooking up a couple in series would have been a cool idea! I was struggling to find Lego pieces that fit snugly inside the magnet, but another coil in front in series would have been an easy way of boosting the signal. And I'm sure you're right about a pre amp. I'm seeing if I can find an affordable solution there. Cheers for the advice!
Try twisting the free ends of the coil. This is usually done to limit the electromagnetic interferences which lead to a noise increase!
That's a great idea, cheers for the suggestion!
I kinda like how it sounds. It reminds me of those early 1900s radio microphones
Better than the pilot's mic on an airplane, that's for sure
Haha true 😂
You could make your own 1910s microphone with this.
Haha true, it already sounds like it's from that decade!
I know it's weird to ask (and I haven't had time to finish the full video), but could you do a mini-tutorial or whatever on how to make a 'bad' microphone with this? I want to hear Edison wax cylinder quality sound, y'know.
i fricking love the old microphones on radios back to 45-70
- 4:33, you need to have shielded wires (wires insulated by a first coasting, metal mesh or film, and then a thicker final coating, creating what resembles a speaker or headphone wire at the least). Also, you would need a pre-amplifier to boost the initial signal, ensuring that that will both be shielded and offer a unclipped, undistorted, and still loud enough signal to at least be decently recognisable.
- 4:39, thinner wire tends to catch more residual signal and for higher voltage and lower current, thicker being for lower voltage yet higher current.
- 8:09, the signal is clearer due to the placement of the coil within a magnet, being closer and of more effect when generating Eddie currents through the coil.
just three helpful tips :>
also, that little piece of adhesive on the coil at 8:39 is restricting some of the physical movement of the coil within the ring magnet.
a thinner membrane like cellophane or a balloon stretched over a ring may give it more response as it will warp easier than a thick material, taking the higher frequencies
Oooh a stretched material over a ring is a great idea - cheers! Might actually give that a try
I cant believe your channel hasn't blown up, this stuff is awesome!
Ha thanks a lot 😁 I'm just happy some folks are getting a kick out of these experiments
If you put a mesh over it it might help a little, modern microphones have a ring around them tightly packing a mesh to it.
Dont know if its possible with legos, but just a heads up!
Electronics hobbyist here, I graduated the german equivalent of highschool this year and will start studying electrical engineering soon and am quite invested in it already.
One thing that would most definitely improve the sound quality is adding a pre amp. Capturing audio will always add noise and when you amplify the audio in post you also amplify the noise floor, this is called signal to noise ratio and by making the input signal louder aka adding a pre amp you can increase the signal to noise ratio and thus decrease the noise in your recording. This would most likely remove the need for noise reduction in post.
Something else I am not very familiar with, but would look into, is the resonance frequency of the membrane, that being the frequency the membrane naturally tries to vibrate at and thus where the microphone is the most sensitive. The resonance frequency of you designs is probably pretty low, meaning it picks up low frequencies well but everything else not so much. Again I am not very familiar with the mechanical side of things so I am not sure how to solve this best.
Howdy! And cheers for your comment - that was very helpful 😁 I'm sure you're right about a better preamp. That audio dongle I was using probably wasn't doing much of anything. Will certainly give that a try in a future version! Also you're totally right about the cardboard membrane - it's likely dampening things an awful lot. Here's hoping the ribbon microphone will do a better job 🤞🤞
Small suggestion, but when making videos involving audio like this, background music is kind of distracting and unnecessary. Otherwise great video :)
Thanks! And you're totally right, in this case I was really debating turning off all music. After trying with and without music, I personally didn't think it distorted the audio coming from the mic, but definitely appreciate that it can be distracting. Will bear that in mind in future - thanks for the feedback!
Put a Metal Housing around the coil and the magnet.
I could bet, that there is a significant amount of electromagnetic background noise.
(that should improve some of the static)
Perhaps you might want to try making a condenser microphone next? It's basically what you've already made, except you use a conductive membrane (like a sheet of copper foil), and a conductive backplane (again, copper foil) instead of a magnet. This creates a capacitor which you can charge with a constant DC power source (a battery).
As the membrane moves, the capacitance will change, which can then be detected by putting a resistor in series and taking the voltage over it as the signal. In theory it should give a much better frequency response, as you can use a much lighter membrane (no coil of wire in the center).
That's a really cool idea, thanks for suggesting! I as vaguely aware of them, but haven't done much research into how they work exactly. Your description sounds reasonably straightforward. Cheers for the tip - I'll certainly look into it some more!
A few suggestions:
1. Try a much lighter or more flexible membrane
2 Make the coil fit inside the magnet or surrounding the magnet (You want the coil to vibrate between the poles)
3. Use a shielded cable for as long as possible. Connect the microphone between the ring and the tip pins. Sleeve is the ground.
4. If you add a pre-amp, you want something like an electric guitar pre-amp, not a microphone one.
All fantastic suggestions, thanks for sharing them! I tried pretty hard to get that coil inside the magnet but really struggled to find the flight fit. But that would have been ideal. Certainly for a future version I'd like to try a better preamp and better membrane materials!
this sounds like old radio broadcasts and i love it
Haha thanks a lot 😁
np
Scarlet Fire, a Dankpods classic. Love it.
😜
The temptation to push the membrane of the mic while its recording lol
Tho I do not entirely know how a microphone's internals look, I do have at least one we could take apart to see what is inside and try to recreate it with Legos.
These microphones reminded me of Alexander G. Bell's "Box phone". So heres a proposition, Try and recreate Bell's box phone.
In order to have high speed/frequency you need low mass.
Try a thinner membrane.
yeah, you need a mic to combo speaker/mic adapter for it to work on your laptop, no dongle needed
I might be a little late and off on my understanding of audio/vibration frequencies but, for what I understand if you were to use a large rectangle diaphragm and offset your coil with a 1/3-2/3 on both axis it should capture more frequencies than a large circle. I liked seeing you distance the magnets and coil from the diaphragm though, good idea!
Ah thanks, I've no idea if that was a good idea or not, but it seemed to work ok. That's an interesting idea to offset the coil - will need to run a few more tests I think!
Great video! You might try using a thinner lighter membrane. A heavier membrane should vibrate more at lower frequencies and a lighter membrane at higher frequencies. Think about how fast you can shake a beach ball vs how fast you can shake a bowling ball. Maybe a balloon stretched over a frame or something similar would work?
you could make the plate for the microphone alot thinner and maybe itll sound better, but you also might want to make it smaller
For sure, that's a good point. I'm sure it can be a lot smaller if I can increase the sensitivity or use a preamp!
The ending microphone sounds like one of those old ones you'd hear in a commercial
Maybe a thinner membrane and a microphone preaamp with a low noise floor? I have combined microphones myself, and wathching this made me want to design my own from scratch! Thank you so much, very inspirering!! :D
Ohh you live in Copenhagen - I live on Bornholm, let me know if I can be at any help! :)
That microphone is like ones from 1920s
A lot of good mics will often have signal processing using one close mic and one far away mic, then using a differential amplifier to only give you the difference, idealy that'd be your voice. Also various different mechanical filters can be applied if you feel like doing it physically rather than with software - 3rd Year Engineering
Love what you're doing here, it's a fun watch
Thanks a lot! Glad it's still interesting to an engineer, as basic as it is. I'll certainly give an amp a try on the next version. Would love to learn more about physical amps though too. I like the idea of minimal 'assistance'
So I know I'm a little late to the game and I also am not an audiophile or engineer. BUT! Maybe a thinner membrane to allow more minute vibrations? Maybe parchment paper? The issue then becomes suspending the coils in the medium (membrane) without the weight causing distortion or tearing.
Once again, I have no working knowledge or qualifications.
Try parchment paper as a membrane. Or feed the coil hovering in the center of a donut shaped magnet
8:01 hmmm.... Radio style
I like how the final result sounds like old-timey radio
I imagine a low-noise preamplifier would help make the signal stronger
Have you tried a softer membrane?
I've tried a few! Softer seems to introduce more bass and higher frequency response drops. But I'm sure there's still loads of experimenting to do to find the optimal balance
Years of 12v audio experience (car audio). The most important thing to remember is your membranes weight/surface area ratio. For input, you want as light as possible while covering as much surface area as possible. Make the membrane out of something thin, light, and durable (think like a piece of one of those clear notebook dividers or something) keep it suspended and about the same size as your original. Next, make your coils tighter. Go down on your inner diameter. Should allow you many more turns, especially with that thin stuff. Your goal is to produce the highest amount of fluctuation, regardless of the actual voltage. For example a low of 1v and a high of 10v is better for input than let's say a low of 5v and a high of 12v. That 2v difference isn't worth the range of audio you will get with the lower voltages. Hope all that makes sense. And my voltage #s are from out of thin air, so take it as an example.
That totally makes sense, really appreciate you sharing these recommendations! For a future version I'll certainly try a thin coil with many windings. As much as I hate dealing with thin wire, I might even go thinner than 38 gauge to get those windings up 😬 Cheers!
This is AMAZING !!!! - it is very interesting blend of tech and Lego
Appreciate it, thanks a lot 😁🙏
I think a thinner membrane would improve legibility, other than that, maybe having a larger coil around the magnet?
I'd imagine you're right in both counts 👌
“This thing with the rubber nipples” 💀💀💀
You need a dynamic microphone circuitry between the computer and the microphone
you should decently try make a headset next for the complete setup
That's totally doable ... A bit challenging to make it interesting though. Certainly worth trying!
An over ear design would sertanly be the easiest way to go, As the speaker it's elf can be much larger.
If you wanted to make it an extra challenge instead of two drivers you could have 4 (2 for highs and 2 for lows) placing the lows in front closer to the ear, as they would be most likely much large than the highs.
Use a nylon string for the suspension of the coil, or use a nylon stalking cut out. The nylon will help pick up more vibrations and, in turn, make the audio clearer. If you use nylon string then the audio will be sharper but also more suseptible to that tinny noise where as the nylon fabric from most thin nylon stalkings are perfect for both catching audio and dampening any high pitched audio.
Also, you need to align your coil and magnet. The coil keeps getting too close to the magnet, which is creating that old-school microphone effect.
You don't really want the coil to wiggle around so much as you want it to move back and forth through the magnet.
Lastly, a few more dampeners from the table to the magnet and coil will help make the background buzzing stop.
Good luck.✌️
That sounds like a great idea, thanks for the suggestion!
Is there a reason why you opted to use a TS connection as opposed to a TRS? If I remember correctly, TRS tend to have cleaner sound due to phase cancelation, or something like that. Been a while since I brushed up on that side of audio, since I’m more of a studio, mix, master, and post engineer.
Really interested to see how you build a ribbon mic. They have a nice sound to them and a pretty cool science all things considered.
Also, if you haven’t done it yet, I’d love to see you recreate a plate style reverb using lego. Who knows, it could become the new thing within the music world, lol.
There sure is a reason - I found a cheap pack of 10 😁 I butchered a bunch of other cables, including TRS, but they all sounded the same to me, so I just went with TS cause it looked cleaner. Terrible reason I know! But thanks for reminding me - really should try a few other cables with the improved mics. Great idea RE the reverb - I only recently heard of it, but it sounds really cool!
I think the rubber suspenders are causing the lower frequency issue. Maybe try suspending from fishing line?
Could very well be. Nylon line isn't a bad idea to try - cheers for the suggestion!
If you put a small capacitor in the line, it should reduce some of the noise.
Huh that's interesting.. I'll see if I have any small ceramics lying around. Cheers!
3:40 That reminds me more of the Connectors from The Talos Principle 1 & 2
Now there's a blast from the past
this is such a nice microphone, it sounds like you are a radiohost from the 1920s, amazing
Haha thanks a lot 😁 Definitely an odd sound profile!
I'm curious how something like parchment paper or a stretched balloon/rubber glove for a membrane would sound. I assumed the cardstock sounded the way it did because it was too thick, but I'm not sure
Actually a few folks have suggested rubber or elastic, so good idea - looks like it's worth testing!
The end result is like an actually usable microphone with quality genuinely comparable to really old professional microphones used in radio broadcasts, which is insane. A big part of that is probably the noise cancellation, but regardless considering how much of a limitation you have, that thing has no right to be as good as it is.
Aw thanks a bunch, appreciate your comment 😁 There's definitely massive room for improvement, but I was just as surprised to see just how easy a basic microphone really is! Certainly easy for anyone to make in an afternoon with minimal parts
such a cool concept, I don't really know eny thing about microphones, but that last one actually works pretty well it just has a old sound to it, keep up your amazing work!
Thanks a lot, really appreciate it! 😁 It definitely worked a bit better than expected, but hoping the ribbon mic will be even better
08:00 There you have it. Now you can understand why in the 20s and 30s people talked funny on the radio! Because microphones just weren't as good then. You can hear high-pitched voices much more easily than bass. This is also why the transatlantic accent was so popular during the time; it was easier to understand dialog over the radio :)
That's so interesting an entire accent can be influenced by something like that!
I think you should use some light and thin materials, like thin paper or plastic
It beats a bunch of webcam microphones I've had over the years, hands down
Haha my condolences 😂
Love the audio series so far! ❤ Anyway, i have a little bit of experience with microphones. There are tons of different kinds and technologies you should read yourself into but these are the tips that i got, that may help.
First i think experimenting with ribbon or string microphones is a step forward but you can also achieve good results with membrane microphones. As you saw a good and big but stiff membrane should get the job done, atleast i believe so, because you want to have a good range of frequency and so far your last design sounded good but i think there were not enough low frequencies and it therefore sounded like an old iphone speaker. And stiff because you want to get rid of afterbounce and background noises of course. I beliefe that helps
I think you should also cover the microphone with a fine piece of cloth! Especially at the front. That should help with the background noises aswell and also act as a pop filter, so you don't get those high bass pops everythime, especially when you say the letter P in any sentence.
And it may help looking at non self powered microphones, where your device, like your PC gives power to the microphone, like via USB signal and the frequency waves get rectified onto the power signal, so that the signal frequency is modulated to contain the audio, which should give you the ability to justify the volume of the microphone.
Hope that helps
Woah thanks for replying with so much detail - really appreciate you taking the time! I'd love to experiment with a membrane microphone. By that, do you mean like a condenser microphone? A pop filter is certainly an easy fix I can add to it! And agree, I think it makes sense to deliver power to boost the signal. To be honest, I'm not too familiar with how that circuitry works, but I'm sure it's relatively straightforward - will look into it some more. Cheers!
@@JamiesBrickJams Yes that is the type of micrphone that i was talking about. Allthough Ribbon or String microphones are generally used for radio station etc., atleast i heard so, condenser microphones are usually all around us, like normal Tablestand microphones. There also exists a type of microphone with large Membranes, which usually are these weird conference microphones, you see in conference rooms a lot. These that look like small ufo's for example.
I think that is as far as my knowledge goes.
Super cool! Can't wait to see what you do with the ribbon design.
Thanks! Fingers crossed it just works at all 🤞😁
You could make a metal mesh cage around the entire mic to reduce some of the noise, probably
I considered that! But figured it'd look kinda ugly - Terrible reason I know 😅 But worth exploring, thanks 🙏
Try to use baking paper, idk if that will help but it's thin and flexible would work for a membrain or even like a disposable rubber clove maybe a balloon
Sounds like an old microphone from 100 years ago. Really cool
Cheers! 😁🙏