G'day, guys and gals (or g'night for me!) I found this interesting article on how to wire up the speakers to a DFPlayer. It's the first image.
Looks like it might be a lil better. Anyone tried this? Just wondered if there were any issues.
It's wrong!!!
The speaker outputs are a mono bridged output. The outputs are biased at half of the power supply voltage which means there is DC across the speaker. When wired correctly, both speaker terminals see the same voltage so there is no voltage across the speaker terminals except when there is a (differential) AC audio signal.
It's a mono signal. There's no way to directly drive stereo speakers from the speaker outputs. You can drive a pair, but left & right are identical (except out-ot-phase).
You can add capacitors to block the DC and it will work. A series capacitor makes a high-pass filter and since DC is 0Hz,it will be blocked. 1000uF will go down to 20Hz at 8-Ohms and 100uF down to 200Hz (you lose the bass). But you'll get half the voltage and 1/4 of the wattage. And you need to reverse the polarity of one speaker to keep them in-phase.
The advantages of a bridge amplifier are that can have a single positive power supply and you don't need a capacitor (making the device smaller), and you can potentially get 4 times times the wattage with a given power supply. You can also eliminate the output capacitor by using an amplifier design that can use positive and negative supplies.
The disadvantage is that it needs two hot-powered speaker connections instead of one signal output and a a ground.
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Nice bit of info there DVDdoug. I thought it was worth putting this one out and you are giving me some thoughts.
You had experience using the left side (of the DFPlayer pins, 4 and 5 down) audio channels on pins just above the speaker inputs? Been trying to get some more info on that but it seems a tad sparse on searches. I think that is what I would be interested in. Even the main PDF for the device is not giving too much info.
I've seen some peeps connecting an amp directly from the speaker outs. I would like to get some info on the best way to use the the 4/5 pins. Maybe should write a new question, ya think mate?
Those pins are line-level stereo output, which can be used as input to a stereo amplifier or earphones. The speaker output is mono only.
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Cheers. Yes that was what I was thinking of. Using those pins direct to an amp. Would like a lil more volume, know what I mean? 10w amp might do the trick. Maybe needs a preamp?
G'day all. Was hoping to use the audio output channels of the DFPlayer. I can call them the 4/5 pins on the left side of the module. The idea is to use them with an amp of some kind.
I have done some searches but not much is coming up. I have seen people using the speaker outs from the 6/8 pins but I am not totally sure that is the best way to do things.
The specs are also showing that the module needs a signal to enable them. Again there is not so much detail in the official PDFs regarding this.
Feel free to keep it on a base level.
This post here might be of some help.
Please do not cross post: flagged.
I don't think he has. Because he is not posting something that he himself has written or been involved with. Cross posting would normally involve them giving a post that they were a part of. It would be some kind of marketing technique to give reference to something they wrote in the past to increase views or bring alive a marketing post that is forgotten.
Not sure what you think of that.
It does not quite fulfil what I was after anyway but I was hoping for some other views or comments/ advice if possible. That post is about triggering the right side of DFPlayer 6/8. I have actually used those for manual control of volume. But not a lot else.
You said you wanted to know how to use pins 4/5, in that post I mentioned, you can see they are connected to a headphone jack. You can do the same going to an amplifier which is also mentioned further down in that post too. You will also need coupling capacitors too to connect the DAC pins to the amplifier circuit(s).
OK mate don't worry about it. I have gone over it a few times, but not sure still. You gave time to answer and find a post. For that I am happy. I didn't want to seem ungrateful. All good.
I can probably throw a circuit together if you want. I should still have a LM386 amplifier or 2.
Any help you have would be great mate. I don't think you were cross posting by the way as well. I'm not sure why someone flagged that. You also gave a link to this forum as well which means it would not be considered cross posting. You a top bloke!
I flagged your post. It is a direct continuation of this thread.
Cross posting wastes everyone's time. You've already been told to use pins 4 and 5 as line level audio out.
I'm not following you here. I asked a question. They are 2 different questions. I didn't even give a link to that question either anyway. Best just to let people answer the questions if they can.
Your two or more topics on the same or similar subject have been merged.
Please do not duplicate your questions as doing so wastes the time and effort of the volunteers trying to help you as they are then answering the same thing in different places.
Please create one topic only for your question and choose the forum category carefully. If you have multiple questions about the same project then please ask your questions in the one topic as the answers to one question provide useful context for the others, and also you won’t have to keep explaining your project repeatedly.
Repeated duplicate posting could result in a temporary or permanent ban from the forum.
Could you take a few moments to Learn How To Use The Forum
It will help you get the best out of the forum in the future.
Thank you.
Not the greatest setup but not bad for a quick throw together.
The 2 big caps are 10uf and the small one going to the speaker is 22uf.
I used this circuit below for the LM386.
And just straight piped pin 4 (DFPlayer) it into pin 3 (LM386)
Top job mate. Sorry if I wasted your time.
na, all good.
The LM386 is considerably less powerful and has higher distortion than the amplifier built into the MP3 player module.