Electret-Condenser Microphone Gain Adjustment Made Simple
Vložit
- čas přidán 20. 12. 2021
- The popular "electret/condenser" microphones of today are inexpensive and provide very good performance for just a few dollars. Often times they come with a fixed load resistor but I have discovered that by making that load resistor variable, the gain can be adjusted without the necessity of building an audio amplifier into the microphone.
- Zábava
Thank you for making this video! Ive been making an interface between my radio and a headset that uses an electret mic. The original design called for a 1K resistor but the gain was really low. By mistake I put in 2.2K when I was tinkering and to my surprise the gain increased. That had me scratching my head. Now I finally understand why!
And Merry Christmas and a Happy New Year to you and your family from Canada.
Merry christmas and a happy new year to you and yours, from sweden.
Good information to know. Merry Christmas and Happy New Year.
Nice, thanks for the tip. The best to you and yours.
I made a couple of "word mistakes". One is if you make the series capacitor a low value say, 0.001 uF you might be able to tailor the output frequency response and attenuate the lows and not the highs. I would think if you use a 10uF capacitor it should be "non-polarized" but the ones we get off Ebay use polarized (standard) electrolytic capacitors. Seems to be OK.
Always great videos and info El Paso. Thanks!
Hello, El Paso.- Very good for the electr. Mike.- For You, much Greetings from Verona city, Italy.- Thanks for All .- Excuse me for the poor English Language ! p.s. : Ciao by Aldo.-
At 2:56 in the video, I say attenuate the highs but mean attenuate the lows...
Thanks for your excellent video. I have a Ubitx Hf kit rig. Have been battling low rf output on voice for some time due I believe to low output from my FET Mike. I will be trying your suggestions out as soon as I can.
Owen Vk5kov from down under of course.
Hi Owen, I hope a mic upgrade works for you. I know the original D-104 elements when they get weak will hardly modulate my transmitter, I think mostly because they have lost their low frequency response. 73 WA4QGA
73.
Congratulations for this démo very cool and interesant.
Where and how connect a vu meter to control the gain effect? Just before the out?
Thanks
I haven't thought about the VU meter but I would think the impedance would be too low and load down the output of the microphone - I have never tried it - but I would suspect a VU meter would need to be located further down the audio chain. I adjust the gain and watch the RF power output of the amplifier to the antenna with a peak reading meter. I personally like the LED peak reading meters better than the Bird 43 style. I guess I just like the blinking lights 🙂 73 WA4QGA
Enjoyed the video on your electret microphone. Also, could you show us the electret condensor mic itself before the install ? I would like to see the gain of the electret microphone in action along with the quality of performance. That is, your gain on the watt meter and modulation as you turn up or turn down the new inline potentiometer. To me that would be a better example of gain from your schematic. Could you possibly update the video on this project ? Thanks Billy Albq. N.M.
Hi Billy,
I don't think a YT video can be updated after posting. We used to be able to add comments to the video in case we said something incorrect but YT notified us and stopped that because they said the comments could not be seen on hand-held devices and most people apparently, watch YT on their phones instead of a PC. I think your suggestions are very good and if I make another video about microphones I will show the mics and how modulation is controlled by the inline pot.
Here is one type I have used from Ebay.
www.ebay.com/itm/354402889211?hash=item52840eedfb:g:LU0AAOSwd0BVtQn0&amdata=enc%3AAQAHAAAAoHDeTqjNAjk9ffBpDFfy8qi53kDjWWP6bhht4t6iouBe7LXzK5nBPeoQ7ynwsHpUX2lnJby1p0wEXY4P9R%2B8OG2if%2FY6op7%2BtJLvGrDe91tNhIsUsuHBAaXgKo0GQsLtt61KyblRCNnw7Ccr%2F5GbhLiWnrGYEIYRkLC6tHeHI20znmjma6W3b16V60PvY5vSYBbczEsu2cSM9E821%2BjDmm0%3D%7Ctkp%3ABk9SR8irhb24YQ
Here are the 69 cent mic elements I have gotten from Amazon - now they are only 59 cents... but you have to buy 10.
www.amazon.com/Cylewet-Cylindrical-Electret-Condenser-Microphone/dp/B01N0VMN9P/ref=sr_1_9?crid=2LMX5TJ9DY3HF&keywords=condenser+mic+element&qid=1674027597&sprefix=condenseer+mic+eleme%2Caps%2C111&sr=8-9
great video. instead of a build-it-yourself, i sent out for a electret microphone amp board already pre-made. . i want to add a volume pot at the audio out but not sure how many ohm pot to get. it has 1 ic, 2 transistors and operates from 5vdc to 12vdc. any ideas? thank you.
To make a zero to full volume output control, you connect the output of your mic amp board to one of the pot and the other end of the pot to ground. The variable signal is then taken off the center pin of the pot and the ground end. Depending on which end you put the signal in and the end you ground will determine if the volume goes up or down when you turn it CW/CCW. Electret-condenser mic elements are fairly low impedance devices so any pot between 2.5K and 10K should work fine. I would likely go with the higher values like 10K. Hope this helps.
@@ElPasoTubeAmps thank you so much for your help. i am trying to keep the costs down and dont want to buy a pile of assorted pots. i will start with a 10k and update results here.( may take awhile...)
hello again! so i have everything hooked up accordingly, and the issue is that its too loud. the "pot" on the board is counterclock all the way- not sure if it even works. i have it running thru 2 pots which i scavenged, both 50 ohm and hooked in a sries circuit. and i cant control the vol. so i sorted some various resistors to put in-line including a 1.5 mega ohm, still too loud. thoughts? thanks!
I don't know but maybe you have the input pot connected wrong ? The input from the, for example, RCA input jack goes to one side of the volume control the other side goes to ground and the wiper goes to the input grid of the first stage. The value of the pot should be something betweel 100,000 and 1 megohm. Also, although it does not have to be, a volume control should be a logrithmic type pot and not a linear pot. Our ear responds logrithmic rather than in a linear manner. Either will work but the linear pot will get loud quickly whereas the log pot will not. Putting a resistor in series, even 1.5 meg is not going to do anything significant as the current flowing thru is in the microamps so there is no voltage dropped across the series resistor. Hope this helps.
thanks for your quick response!! the amp in question (if you care to look) "DC 5V-12V LM386 electret microphone power amplifier board" in the walmart search, it shows the 2 transistor board with input for electret mike. i dont have a pot in that circuit, just wired direct. the pots i used are both for the audio out. i will look to the logrithmic pots and see what i can find, not familiar with those. thanks again!
No man, following to the letter all i got was a great deal of noise, it improved slightly removing the 2.2k and just using the variable. even that was nothing to brag about
That's not good... Are you using this microphone on new equipment like iCom, for example, or vintage equipment like vacuum tube Collins equipment?
@@ElPasoTubeAmps I am using it as an external Mic for a Sony Digital voice recorder. ( Model: ICD-PX312 ) I am making a Mic array using a NE5532 TDA1308 Mono Audio Signal Input Mixing Board
@@home_Grown_studio One of the things that I have found that surprises me with these little mic elements, is they work very well into a high-Z input like vacuum tube circuits. Input Z is around 1 megohm. I have also tried to use them on modern solid state devices like iCom radios and they don't work so well. The input Z of the iCom type radios is a low Z impedance - not exactly sure what it is but I believe in the K ohm range. I bet your Sony device is a low Z input. Not sure how to help at this point.
@@ElPasoTubeAmps Actually I am getting close to achieving my goal. Been playing around with resisters getting better. Before I make the connections to the mixer I just want a good sound with little noise as possible. Anyway, Thx for the posts they are appreciated
@@ElPasoTubeAmps600 ohms for newer radios