When buying populated PCBs or kits rather than finished amplifier, especially off ebay from an unknown source, "quality control" is indeed difficult.
There are however distributors that would exchange a board if there is a problem.
You could also opt to buy a evaluation module from a manufacturer like TI:
https://www.ti.com/tool/TPA3220EVM-MICRO#buy
There is also kits out there for LM3886.
This one is highly recomended:
TPA3255 2x260W 2Ch Class D Audio Amplifier|Amplifier| - AliExpress
maybe something cheaper and not so powerful:
Amplifier Board - AIYIMA A2D859 - TPA3116D2 | 2.0 Channel 2*120W | Pow
It all comes down to what you are willing to do (solder, handle SMD etcpp., buy additional parts like volume potentiometer, sockets) to make that kit into an amplifier. The choice of amplifiers with reasonable->very good quality out there is rather big.
PS.:
And to repeat myself: have a look at the swap meet, at the vendors and manufacturers being part of the forum and also the group buys.
There is a recent group buy for a pretty much state-of-the-art class-d-amplifier.
Maybe that´s too much for you but it´s well priced for what it is:
XRK RTR TPA3255 Reference class D Amp GB2
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Right now the LM 386 is hooked up to my laptop headphone out and a and old pc speaker, and sounds loud enough. Earlier tests it did not sound so loud, maybe there was something in the connections.
It sounds even better in Audacity with 'leveling' under 'distortion' so there is some distortion... The chip does not get very hot.
Wait a minute, I had set it to 1.5 V . Changed that to 3.5V and it seems to handle higher volumes without so much distortion. The datasheet says it can go from 4V to 18V I am not sure what to use. The speaker is on the tabletop, so mounting them in stands in open baffle concept and angling them upwards should help some more.
It sounds even better in Audacity with 'leveling' under 'distortion' so there is some distortion... The chip does not get very hot.
Wait a minute, I had set it to 1.5 V . Changed that to 3.5V and it seems to handle higher volumes without so much distortion. The datasheet says it can go from 4V to 18V I am not sure what to use. The speaker is on the tabletop, so mounting them in stands in open baffle concept and angling them upwards should help some more.
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Let's look at the chips suggested:
TDA2030: AC / DC 9V-12V input, 4-8 Ω impedance output
Does it need a heat sink? Power requirements are OK. I will be running it off an AC power adapter, any filtering suggested?
LM1875: Power - 12-16 V Dual AC. Needs more power and large heat sink
I had a BA5406 chip PC speaker board that needed repair. Is this a good option? Never heard it play though.
The lm386 still sounds a little harsh, though. Not sure what to do about that.
TDA2030: AC / DC 9V-12V input, 4-8 Ω impedance output
Does it need a heat sink? Power requirements are OK. I will be running it off an AC power adapter, any filtering suggested?
LM1875: Power - 12-16 V Dual AC. Needs more power and large heat sink
I had a BA5406 chip PC speaker board that needed repair. Is this a good option? Never heard it play though.
The lm386 still sounds a little harsh, though. Not sure what to do about that.
There is a description of the board here:
LM386 Audio Amplifier Amplitude Module Board with Adjustable Resistance Control Potentiometer buy in Pakistan
From that web page:
What does this mean, does it increase gain or volume?
LM386 Audio Amplifier Amplitude Module Board with Adjustable Resistance Control Potentiometer buy in Pakistan
From that web page:
What does this mean, does it increase gain or volume?
The "CFL Conversion" is a very simple amplifier, which will have low power and high distortion. I don't imagine the results are worth the hassle...still a fun and simple build perhaps for the beginner.
LM386 will be able to produce a bit more power and with lower distortion if you supply more voltage. 3.5v is not even within the recommended operating range. But it is still not going to give very satisfactory results, in my opinion.
LM386 will be able to produce a bit more power and with lower distortion if you supply more voltage. 3.5v is not even within the recommended operating range. But it is still not going to give very satisfactory results, in my opinion.
Low power and maybe low efficiency as well. Worth trying sometime. Sound quality has to be tested.
In the meantime I will proceed with the LM 386, looking at input power requirements here:
https://www.ti.com/lit/ds/symlink/lm386.pdf
5-12 V power supply. Power requirement:
In the meantime I will proceed with the LM 386, looking at input power requirements here:
https://www.ti.com/lit/ds/symlink/lm386.pdf
5-12 V power supply. Power requirement:
> Low power and maybe low efficiency as well.
The maximum efficiency of resistor-loaded audio amplifier is 8%. And it idles hot. An AB amp like LM386 can exceed 50% efficiency and idle hardly-warm.
The sound quality is known from the 1950s when this was leading-edge.
The maximum efficiency of resistor-loaded audio amplifier is 8%. And it idles hot. An AB amp like LM386 can exceed 50% efficiency and idle hardly-warm.
The sound quality is known from the 1950s when this was leading-edge.
Attachments
The TEA 2025 amplifier has the following current flow, checked with a multimeter:
TEA 2025
Zero Volume : 40 mA
Max Volume (Playing Music) : 90 mA
For this as well as the LM386 amplifier, could I get away with using a 9V 300mA AC/DC adapter? It seems reasonable, though there may be something I have missed.
TEA 2025
Zero Volume : 40 mA
Max Volume (Playing Music) : 90 mA
For this as well as the LM386 amplifier, could I get away with using a 9V 300mA AC/DC adapter? It seems reasonable, though there may be something I have missed.
I'm not sure if it's difficult or expensive to obtain electronics where you are, but it seems as if you are sinking much effort into building what will ultimately be a badly performing amplifier.
There's an English expression "you can't make a silk purse from a sow's ear" (a sow being a pig) and it does, in my opinion, apply to using LM386 or TEA2025 in anything other than a child's toy or pocket radio.
If you want a decent amplifier for home use, for little money and effort, I would highly recommend a TPA3116d2, powered by a used laptop supply (around 19v and 3A or more). Even a 12v 2A supply from a router/modem will do at a pinch, you'll have less power but probably enough.
Get the simplest module you can find with no frills, they're dirt cheap, and splash out if you must on a stepped attenuator for the volume so you get even volume on both channels.
This will give you easily 15W of power without the need for a heatsink, very low distortion especially compared with the likes of LM386 and TEA2025, and low noise.
I would also suggest you ditch the alligator clips and invest in or borrow a soldering iron, some solder, and a pair of side cutters so you can solder the connections. You don't need anything fancy, a simple 15w or 25w iron will do the job.
All the best with your project! May you find your audio nirvana.
There's an English expression "you can't make a silk purse from a sow's ear" (a sow being a pig) and it does, in my opinion, apply to using LM386 or TEA2025 in anything other than a child's toy or pocket radio.
If you want a decent amplifier for home use, for little money and effort, I would highly recommend a TPA3116d2, powered by a used laptop supply (around 19v and 3A or more). Even a 12v 2A supply from a router/modem will do at a pinch, you'll have less power but probably enough.
Get the simplest module you can find with no frills, they're dirt cheap, and splash out if you must on a stepped attenuator for the volume so you get even volume on both channels.
This will give you easily 15W of power without the need for a heatsink, very low distortion especially compared with the likes of LM386 and TEA2025, and low noise.
I would also suggest you ditch the alligator clips and invest in or borrow a soldering iron, some solder, and a pair of side cutters so you can solder the connections. You don't need anything fancy, a simple 15w or 25w iron will do the job.
All the best with your project! May you find your audio nirvana.
It is not difficult at all to obtain electronics - unfortunately we are under restricted movement right now due to you know what 19 and deliveries will be delayed as well. The LM386 and PAM 8403 were both purchased locally from a place that delivers (stopped delivering right now). Unfortunately the PAM 8403 seems to have burned out.
This is a learning experience, and I thought I might as well experiment with these things I bought many years ago, and get the case, connections all sorted out as well as using it as a laptop speaker amplifier in as a temporary measure with some mini open baffles.
The TPA seems like a nice amplifier, and it has a seperate subwoofer channel that will come in handy, and I could run it off an adapter: 80W per channel is certainly not needed but then again I have the vintage SONY receiver to work with for the moment.
From AMAZON:
Clyxgs TPA3116D2 2.1 Digital Power Amplifier Board, 2x80W+100W(Bass) Audio Stereo AMP Module for Audio System DIY Speakers 12-26V
Brand: Clyxgs
4.3 out of 5 stars 108 ratings
Price: $15.99
✅ Two TPA3116D2 chips – one for the left/ right channel power amplify and the second is in bridge connection with the front NE5532 to drive the subwoofer.
Is there a simpler board? Let's see.
The alligator chips are only temporary. I have soldered stuff including the input wire that came off the TE2025 board: works fine now. I prefer to go solderless but there we go again.
I have already seen the promised land of audio, my regret is that I did not experiment when I was a teenager and I would have had a serious system by now. There was no internet then, but there were people I guess.
One last question - apart from making sure the connections are good, is there anything I can do to make the LM sound better? Capacitors, filters etc?
This is a learning experience, and I thought I might as well experiment with these things I bought many years ago, and get the case, connections all sorted out as well as using it as a laptop speaker amplifier in as a temporary measure with some mini open baffles.
The TPA seems like a nice amplifier, and it has a seperate subwoofer channel that will come in handy, and I could run it off an adapter: 80W per channel is certainly not needed but then again I have the vintage SONY receiver to work with for the moment.
From AMAZON:
Clyxgs TPA3116D2 2.1 Digital Power Amplifier Board, 2x80W+100W(Bass) Audio Stereo AMP Module for Audio System DIY Speakers 12-26V
Brand: Clyxgs
4.3 out of 5 stars 108 ratings
Price: $15.99
✅ Two TPA3116D2 chips – one for the left/ right channel power amplify and the second is in bridge connection with the front NE5532 to drive the subwoofer.
- ✅ DC 12-26V(24V recommended) wide input voltage; 3.5mm audio input jack; 3-pin audio input jack; Volume/ Subwoofer/ Stereo knob adjustment.
- ✅ 80W*2+100W 2.1 channels (left+right+subwoofer), high efficiency and low heat.
- ✅ 3.5 mm audio jack, 2.1 mm DC power jack and phoenix speaker connectors for easy hookup, an optional 3-pin connector for internal line-in audio is available (wiring harnesses not included).
- ✅ Widely used in DIY bookshelf loudspeaker, car audio components, home theater audio system and more.
Is there a simpler board? Let's see.
The alligator chips are only temporary. I have soldered stuff including the input wire that came off the TE2025 board: works fine now. I prefer to go solderless but there we go again.
I have already seen the promised land of audio, my regret is that I did not experiment when I was a teenager and I would have had a serious system by now. There was no internet then, but there were people I guess.
One last question - apart from making sure the connections are good, is there anything I can do to make the LM sound better? Capacitors, filters etc?
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This answer has some suggestions.
audio - How to improve lm386 amplifier circuit - Electrical Engineering Stack Exchange
I reduced the gain and also increased the power supply to 9V which marginally improved the sound. Putting an inductor in series cut out some of the high frequency harshness. Maybe I need a tweeter for the highs after all, and let this speaker deal with other stuff.
Echoes of what was said here:
audio - How to improve lm386 amplifier circuit - Electrical Engineering Stack Exchange
I reduced the gain and also increased the power supply to 9V which marginally improved the sound. Putting an inductor in series cut out some of the high frequency harshness. Maybe I need a tweeter for the highs after all, and let this speaker deal with other stuff.
Echoes of what was said here:
As low power amplifier options go these days, the LM386 is neither a high fidelity nor an high efficiency choice. Good luck!
This is fun.
Many many years ago (1988 or so) that an amplifier should be matched to the speakers. This was news to me. With this cheap little LM as well as other amps I intend to develop both the amplifiers and speakers as one system, and tune each one accordingly. I am not a commercial producer of amplifiers so I do not need to make my amplifier work flawlessly with every speaker on the planet. (as if).
Is this an useful idea?
Many many years ago (1988 or so) that an amplifier should be matched to the speakers. This was news to me. With this cheap little LM as well as other amps I intend to develop both the amplifiers and speakers as one system, and tune each one accordingly. I am not a commercial producer of amplifiers so I do not need to make my amplifier work flawlessly with every speaker on the planet. (as if).
Is this an useful idea?
1pcs 8Ohm 8R 3W Speaker Round 3-inch Speaker Magnetic Diameter 77mm High Quality | eBay
Should be a good match for LM386
Should be a good match for LM386
You mean the "High Quality" part. . What I actually have one similar to this one, marked 4 Ohms
3" inch 8Ohm 8Ω 15W Full Range Audio Speaker Stereo Woofer Loudspeaker HOT E2H8 | eBay
This system is used as an improvement of a laptop speaker system : external speaker, which it is.
The person at Lankatronics who sold it to me should have told me: "by the way it sounds terrible". But I never told him it was for Hi-Fi. He also sold me the PA 8403.
They sell components for electronic projects mostly, and their service is very good, with door to to delivery (since suspended).
They are now offering this: the LM358. Very tempting at 15 cents.
Operational Amplifier ICs
Just Kidding !!!
. What I actually have one similar to this one, marked 4 Ohms3" inch 8Ohm 8Ω 15W Full Range Audio Speaker Stereo Woofer Loudspeaker HOT E2H8 | eBay
This system is used as an improvement of a laptop speaker system : external speaker, which it is.
The person at Lankatronics who sold it to me should have told me: "by the way it sounds terrible". But I never told him it was for Hi-Fi. He also sold me the PA 8403.
They sell components for electronic projects mostly, and their service is very good, with door to to delivery (since suspended).
They are now offering this: the LM358. Very tempting at 15 cents.
Operational Amplifier ICs
Just Kidding !!!
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Hi
Did you try this?
John audio tech: Make the PERFECT LM386 audio amplifier?
Make the PERFECT LM386 audio amplifier? - YouTube
chris
Did you try this?
John audio tech: Make the PERFECT LM386 audio amplifier?
Make the PERFECT LM386 audio amplifier? - YouTube
chris
Perfecting the LM?
I watched this but I was not sure how to add components to a board that is already made. I have to watch again and figure it out, thanks.
Making it 'perfect' is always an interesting thought. I re-connected my LM setup with direct connections to the speakers (no speaker terminals) and it does sound better. Did the open baffle enclosures and got a 300mW AC adapter to power it at 9V which will finally result in 4.5V x 2 and should not make it too hot. One thing I do not want is a hot amplifier. Sound quality is not too bad at that voltage. As a benefit, incorrect power connections do not burn the thing up - it does not light up.
I watched this but I was not sure how to add components to a board that is already made. I have to watch again and figure it out, thanks.
Making it 'perfect' is always an interesting thought. I re-connected my LM setup with direct connections to the speakers (no speaker terminals) and it does sound better. Did the open baffle enclosures and got a 300mW AC adapter to power it at 9V which will finally result in 4.5V x 2 and should not make it too hot. One thing I do not want is a hot amplifier. Sound quality is not too bad at that voltage. As a benefit, incorrect power connections do not burn the thing up - it does not light up.
Further Testing
One of the recommendations from the video was to use a 8 Ohm speaker instead of 4 Ohms or to add a resistor in series. Let me see the datasheet: while it does not have anything on power, it does show that above 9 Volts the output voltage does not increase very much, and with an 8 Ohm speaker it outputs twice the voltage swing.
Testing commenced with a large Sony ES-333 speaker : 8 Ohms impedance, part of a Hi Fi system. I was pleasantly surprise. At first the sound was not very loud and sounded weak, but after turning up the volume on my HTC Explorer (also vintage) and turning up the gain a little bit, I was on the way to some great listening. Clarity was good after I turned down the gain a little, and the bass was there. The music was actually enjoyable, without any sense of distortion. All this from 300mW or less. I do not understand power, even if it is logarithmic.
In a pinch I could listen to this amplifier all day with these speakers, although I am totally convinced that amplifiers and speakers should be tested and matched as a pair (or a trio?).
In short, quite amazing and satisfying. I am wondering what to do, to move the ES 333s off the large cabinet and put them on the floor and hook them up permanently to the LM 386 (by the way it runs way cooler running the 8 Ohms than the 4 Ohms).
Curioser and curioser.
One of the recommendations from the video was to use a 8 Ohm speaker instead of 4 Ohms or to add a resistor in series. Let me see the datasheet: while it does not have anything on power, it does show that above 9 Volts the output voltage does not increase very much, and with an 8 Ohm speaker it outputs twice the voltage swing.
Testing commenced with a large Sony ES-333 speaker : 8 Ohms impedance, part of a Hi Fi system. I was pleasantly surprise. At first the sound was not very loud and sounded weak, but after turning up the volume on my HTC Explorer (also vintage) and turning up the gain a little bit, I was on the way to some great listening. Clarity was good after I turned down the gain a little, and the bass was there. The music was actually enjoyable, without any sense of distortion. All this from 300mW or less. I do not understand power, even if it is logarithmic.
In a pinch I could listen to this amplifier all day with these speakers, although I am totally convinced that amplifiers and speakers should be tested and matched as a pair (or a trio?).
In short, quite amazing and satisfying. I am wondering what to do, to move the ES 333s off the large cabinet and put them on the floor and hook them up permanently to the LM 386 (by the way it runs way cooler running the 8 Ohms than the 4 Ohms).
Curioser and curioser.
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