I purchased two LM 386 and a PAM 8403 amplifier boards locally in 2016 hoping to build my own chip amplifier. With the TEA 2025 connected and driving my desktop open baffles, I thought it good to connect the LM 386 and check it for sound. There are reviews all over the tube but how does in sound?
This is a follow on from this thread: New Sleek Chip amp project however that thread is ending with the TEA 2025 based system so it seems good to create a new thread. The design should be similar though:
https://www.diyaudio.com/forums/att...6d1516102314-sleek-chip-amp-project-amopl-jpg
At first listen it sounded harsh, and a little bright. I connected it to my open baffles and then to a large Sony mini-fridge type speaker, the ES 333 or something. Without any amplification (yes I tried that ) there was hardly any sound but with the amplifier the music was soft, distorted and muffled. Maybe it was the source, as CD-derived track and Deezer type streaming sounded better. It plays quite loud 70dB at 10 cm from the speaker front.
Sorry for the blurry pix - actual setup. There is a nice clear description of the lm386 here:
OK, so the amplifier project has started - this will go in the living room to drive my 'bookshelf' OB speakers. Enclosure design next.
Questions:
How do I improve the design? One reviewer suggested a large capacitor across power input to increase bass response.
How do I incorporate bass and treble controls into the design?
This is a follow on from this thread: New Sleek Chip amp project however that thread is ending with the TEA 2025 based system so it seems good to create a new thread. The design should be similar though:
https://www.diyaudio.com/forums/att...6d1516102314-sleek-chip-amp-project-amopl-jpg
At first listen it sounded harsh, and a little bright. I connected it to my open baffles and then to a large Sony mini-fridge type speaker, the ES 333 or something. Without any amplification (yes I tried that ) there was hardly any sound but with the amplifier the music was soft, distorted and muffled. Maybe it was the source, as CD-derived track and Deezer type streaming sounded better. It plays quite loud 70dB at 10 cm from the speaker front.
Sorry for the blurry pix - actual setup. There is a nice clear description of the lm386 here:
OK, so the amplifier project has started - this will go in the living room to drive my 'bookshelf' OB speakers. Enclosure design next.
Questions:
How do I improve the design? One reviewer suggested a large capacitor across power input to increase bass response.
How do I incorporate bass and treble controls into the design?
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LM386 is a low power amplifier, a fairly old class AB design with less than 1W output and high distortion. It's really for things like clock radios.
I think you will have better results with PAM8403 which is a newer class D and has 3W output.
But I would instead look to the TPA3116d2. Modules can be had cheap and this chip is good for 50WPC with the right power supply. With a modest 12v supply it's good for 15W or so and with very low distortion.
I think you will have better results with PAM8403 which is a newer class D and has 3W output.
But I would instead look to the TPA3116d2. Modules can be had cheap and this chip is good for 50WPC with the right power supply. With a modest 12v supply it's good for 15W or so and with very low distortion.
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I bought these years ago when I was searching for options to build an amplifier. Finally settled for salvaged PC speaker amp, but I just took out the lm386 the other day to see how it sounds. I am quite satisfied with the detail in that thing, and the punch. I tested it out with the SONY ES 333 large speakers and plays acceptably OK but the phone has to be turned up to full volume, a line out from a CD player would give better power, even a PC headphone out should have more power. Now that I have it might as well use it: use what you have.
One lesson I learn is that the amplifier and speaker must match, must be tested and work together.
The PAM8403 has higher power, but I am really worried about the class D switching design. The other class D amp I used was the Lepai and that was terrible, loud but empty sounding and I gave it away. That was a class D as well.
Lets see if it is too small to connect using crocodile clips, nothing but testing them out to see how it will sound.
Edit: Crocodile clips just fit, so I will go ahead with the test.
Meanwhile, I look for the TPA3116d2 board. 12V and how many amps - will an AC adapter giving 1000 mA work?
Its a nice board, but need to figure out the power supply. Bass and Treble controls too.
https://www.amazon.com/Clyxgs-Subwoofer-TPA3116D2-Amplifier-Recommended/dp/B07KWS33LP
One lesson I learn is that the amplifier and speaker must match, must be tested and work together.
The PAM8403 has higher power, but I am really worried about the class D switching design. The other class D amp I used was the Lepai and that was terrible, loud but empty sounding and I gave it away. That was a class D as well.
Lets see if it is too small to connect using crocodile clips, nothing but testing them out to see how it will sound.
Edit: Crocodile clips just fit, so I will go ahead with the test.
Meanwhile, I look for the TPA3116d2 board. 12V and how many amps - will an AC adapter giving 1000 mA work?
Its a nice board, but need to figure out the power supply. Bass and Treble controls too.
https://www.amazon.com/Clyxgs-Subwoofer-TPA3116D2-Amplifier-Recommended/dp/B07KWS33LP
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Also from reading your review, it seems like you're expecting bass from 4" speakers with an open baffle... I'm afraid that's not going to really happen. Track down some better speakers, if we're talking vintage and not some of the newer small high-excursion subwoofer designs, 6" at the absolute minimum in a well designed enclosure to get anything which approaches bass. 8, 10, 12" even better (in an appropriate enclosure) especially with low power.
As for bass and treble controls, IMHO, you don't really need them. Especially if your goal is to pull together as cheap a setup as will give you a decent sound.
Good luck with your experimenting [emoji106]
As for bass and treble controls, IMHO, you don't really need them. Especially if your goal is to pull together as cheap a setup as will give you a decent sound.
Good luck with your experimenting [emoji106]
So you are going to spend > $100 (including your custom made chassis and cabinet, plus power supply and hardware) so as not to "waste" woefully inadequate LM386 chips (value some 30 U$ cents).
Yes, I can see the logic in that
Just read your 20W amp "review":
Yet now you claim to be happy with a 300mW amp?
Yes, I can see the logic in that
Just read your 20W amp "review":
Yea, cardboard open baffle confirmed.
Yet now you claim to be happy with a 300mW amp?
Reasons...
Thanks. A little clarification is needed here, what I do is not immediately obvious to the outside observer.
I started off building all sorts of speakers, cardboard, yes, but also a plywood box to house the 6 1/2 inch woofers (Fr = 60 Hz or so ) and the tweeter. Results were disappointing. Since I was not getting enough bass anyway, I opted for an open baffle design hoping to add a subwoofer later.
I listen at extremely low listening levels : 70 dB 10 cm from the speakers. Under these conditions I have found loudness and bass controls very helpful, or at least a software equalizer. This may be possible with a good speaker, so I admit I made a mistake: I should have started out sourcing and testing the woofer first of all. With the living room system I find that the "Bookshelf" open baffle has just enough bass for me.
To recap: open baffles are a last desparate move after trying to get decent cabinets with bass, off on an, my first set of speakers was in 1991. Proper construction and sealing is the key, I might just contract out the build, however I need a guarantee that it will work.
Thanks. A little clarification is needed here, what I do is not immediately obvious to the outside observer.
I started off building all sorts of speakers, cardboard, yes, but also a plywood box to house the 6 1/2 inch woofers (Fr = 60 Hz or so ) and the tweeter. Results were disappointing. Since I was not getting enough bass anyway, I opted for an open baffle design hoping to add a subwoofer later.
I listen at extremely low listening levels : 70 dB 10 cm from the speakers. Under these conditions I have found loudness and bass controls very helpful, or at least a software equalizer. This may be possible with a good speaker, so I admit I made a mistake: I should have started out sourcing and testing the woofer first of all. With the living room system I find that the "Bookshelf" open baffle has just enough bass for me.
To recap: open baffles are a last desparate move after trying to get decent cabinets with bass, off on an, my first set of speakers was in 1991. Proper construction and sealing is the key, I might just contract out the build, however I need a guarantee that it will work.
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Explanations...
The cardboard open baffle was for testing, they are now gone.
I am experimenting with the LM386 and maybe the PAM8403 : making amplifier chassis, fitting the connectors etc. The point of it is to make mistakes on a small scale before going to a real large amplifier. I don't intend to spend much at all for now.
300mW: it is all in the listening, 300mW, 2.3W, 35 Watts per side on the Sony ES receiver and 50W per side in the car with the Pioneer. To my ears, power matters of course, but exploring either end of the spectrum matters.
Unusually, I am sharing a dwelling place with other people, and I do not think I can listen at 70+ dB except for short 5 minute sessions. But it works for me.
So you are going to spend > $100 (including your custom made chassis and cabinet,...
Yea, cardboard open baffle confirmed.
Yet now you claim to be happy with a 300mW amp?
The cardboard open baffle was for testing, they are now gone.
I am experimenting with the LM386 and maybe the PAM8403 : making amplifier chassis, fitting the connectors etc. The point of it is to make mistakes on a small scale before going to a real large amplifier. I don't intend to spend much at all for now.
300mW: it is all in the listening, 300mW, 2.3W, 35 Watts per side on the Sony ES receiver and 50W per side in the car with the Pioneer. To my ears, power matters of course, but exploring either end of the spectrum matters.
Unusually, I am sharing a dwelling place with other people, and I do not think I can listen at 70+ dB except for short 5 minute sessions. But it works for me.
I have a problem with headphones - I feel they give me temporary hearing loss and I did suffer hearing loss from an ear infection in the 1990s, connected to having closed ear headphones on for 7 hours a day or so.
Headphones are out. I will attempt to sound proof the room and choose listening times in the living room.
There is something of a discussion of listening at low volumes, I would think you need large sensitive speakers. I think. Where can I buy 8 inch woofers now...
So you are going to spend > $100 ....
....
Yet now you claim to be happy with a 300mW amp?
LM386 M1 chip it is, the lowest power out of the 300/600/1000 m W variations.
How did you know it was the M1? Anyway I may just go ahead and build it for my laptop speaker project. Yes I tested it out, and guess what 300 mW is not very loud.
I can't find the smiley for embarrassed...
Oops!
Try your other board and see if you like it. (PAM..)
Other than that I also think that investing all that time and money you should not try to save every penny on the actual chip.
There are still relatively cheap chips that are much much better than a LM386.
TDA2030, LM1875, TDA7293, TDA7294, LM3886.
The latter 3 are also found in commercial "audiophile" offerings.
Lots of people like TPA3116/TPA3118 which are very cheap as well (complete boards; but SMD mostly).
Depends on what you want to achieve and actually do yourself (enclosure design...?).
And maybe ask here before you buy another board.
If you´re lucky maybe you´ll find populated boards here in the forums ("swap meet").
Other than that I also think that investing all that time and money you should not try to save every penny on the actual chip.
There are still relatively cheap chips that are much much better than a LM386.
TDA2030, LM1875, TDA7293, TDA7294, LM3886.
The latter 3 are also found in commercial "audiophile" offerings.
Lots of people like TPA3116/TPA3118 which are very cheap as well (complete boards; but SMD mostly).
Depends on what you want to achieve and actually do yourself (enclosure design...?).
And maybe ask here before you buy another board.
If you´re lucky maybe you´ll find populated boards here in the forums ("swap meet").
The PAM 8403 is overheating and is probable burned out. It is not the money: I did not look at the specs and purchased these from a local electronics store instead of purchasing them online.
I should have bought two PAM 8403s. I will probably go for those boards you mentioned, however, how do you deal with quality control issues?
I should have bought two PAM 8403s. I will probably go for those boards you mentioned, however, how do you deal with quality control issues?