Shearching audio amplifier schematic - Page 1
Forum section: electronics / beginners

author: dbernotas
author_rank: Newbie
timestamp: January 06, 2021, 02:32:58 pm
content: HelloI have a problem and I am hoping someone could help meI am looking audio amplifier schematic. I know there are tons of them on internet, and this is one of problem: I have no idea what to choose...I will be building it my self, so it should be an easy one to make.I will use it to power up 2x3wats (4 ohms) speakers and one 6w 6(ohms) "subwoofer". All speakers are from old 2.1 audio system used with my old pc.I would like to make it stereo and it would be nice to regulate "bass" level separately.

author: bob91343
author_rank: Super Contributor
timestamp: January 06, 2021, 08:27:17 pm
content: It's a bit ambitious for a homebrew project. You can find a unit that does what you need and look at the diagram. But there are too many specifications for a simple answer.

author: Le_Bassiste
author_rank: Frequent Contributor
timestamp: January 06, 2021, 09:04:44 pm
content: Quote from: dbernotas on January 06, 2021, 02:32:58 pmit really depends on how comfortable you are with designing (calculating) and troubleshooting electronic circuits.maybe, the lower powered (exactly the range you specified) integrated audio amplifiers are a good starter for you.for example, TDA2003. super simple circuit and dead cheap. a single one for each L and R, and another two in "bridged" configuration for the subwoofer should do for your purpose.have a look:https://www.circuitbasics.com/complete-guide-to-build-a-10w-amplifier-with-the-tda2003/

author: Larryc001
author_rank: Regular Contributor
timestamp: January 07, 2021, 06:08:02 am
content: There are lots of kits for sale on the internet which have all parts and instructions for probably less than buying parts separately. Great for beginners. Here is one I particularly like because it looks kinda trick.https://www.ebay.com/itm/Single-End-6J1-FU32-Tube-Amplifier-Kit-HiFi-3W-3W-Power-Amp-Audio-Amplifier-Kit/353344738491?hash=item5244fcd4bb:g:WNcAAOSwS3Ff9oBQ

author: andy3055
author_rank: Super Contributor
timestamp: January 07, 2021, 07:13:39 am
content: Take your pick here:https://www.ebay.com/sch/i.html?_from=R40&_trksid=p2334524.m570.l1313&_nkw=12+volt+audio+amplifier+kit&_sacat=0&LH_TitleDesc=0&_osacat=0&_odkw=12+volt+audio+amplifier

author: dbernotas
author_rank: Newbie
timestamp: January 07, 2021, 08:44:55 am
content: Thanx all for replaying.I will be trying to do what Le_Bassiste suggestedSeems interesting and not too complicatedWill be updating on how its going

author: dbernotas
author_rank: Newbie
timestamp: March 26, 2021, 12:09:14 pm
content: Hello again good people.I am back. After some long trials and errors i made some progressI took schematic from this site and made some changeshttps://xtronic.org/circuit/amplifier/circuit-power-audio-amplifier-with-tda2030-2-1/My approach looks like thishttps://drive.google.com/file/d/1zsTLtkXBN6R8aFa591uhQWQGm2qU3U-l/view?usp=sharingDifference is that I replaced TDA2030A amp circuit. I took it from datasheet.And as for my power supply I didn't have transformer with center tap, so I found schematic how to make power rails.And now i have some question:Is it good to use such power supply without center tap transformer?I use "pre AMP circuit" NE5532, but I don't understand why it is used, as I can hear my bass speaker is much more louder than left and right speaker. Maybe I could/should this kind of pre amp circuit on left and right channel ?how to make effective low pass filter, because now my subwoofer sounds like big loudspeaker, I can hear great amount of mid range sounds?Is it necessary/recommended to add electrolytic capacitor in series to speaker to save from dc voltage? What would be cons and pros ?Thank you in advance.

author: mariush
author_rank: Super Contributor
timestamp: March 26, 2021, 12:30:02 pm
content: I'd suggest going up to TDA2050, as it allows you to go with as low as 9v (so you can power it from a 12v power supply, or a laptop adapter 16.5 .. 18.5v if you want to) and it's dead simple to use.You can still buy clones from lcsc for under 50 cents each:1. HGSEMI TDA2050TB :https://lcsc.com/product-detail/Audio-Power-OpAmps_HGSEMI-TDA2050TB_C434516.htmlThe datasheet also contains very clear schematic and explanations :https://www.st.com/resource/en/datasheet/cd00000131.pdf(I've also attached it to this post)The clones probably won't have same maximum power and will probably have smaller transistors inside so I probably wouldn't power them with near the maximum voltages, but should still be good for 20-25 watts.Here's a DYI project with it, though they use the split power supply version, using a transformer to get negative and positive voltages :https://diyaudioprojects.com/Chip/DIY-TDA2050-Hi-Fi-Chip-Amplifier/Keep in mind that these chips are only around 65-70% efficient, so you really need a heatsink on them if you give them lots of voltage and aim for high wattage.

author: pqass
author_rank: Super Contributor
timestamp: March 27, 2021, 12:10:10 am
content: In case you are not aware, a wonderful resource for all things audio can be found here:https://sound-au.com/The project descriptions and articles are thorough. A very good start for a beginner.I'm not affiliated; just a happy user.