Hi guys,
Firstly what a fantastic forum, lots of great info here! Actually a little to much info actually as I have spent days and many many hours trolling the pages for info...
I will explain why later but can I first ask a relatively simple (I think?) question?
Can someone kindly summarize the current budget bluetooth capable class D amp boards?
Or more specifically the chips I guess, as I realize that there are many different boards with the same chips.
So now the background on why. I have a little knowledge but admittedly limited. I've always got some project on the go (often electrical) and recently I picked up a TPA3116 board. I grabbed an old speaker and built a portable battery powered bluetooth boombox. It was really popular and I have since built a few more for friends and have requests for more. I have a few TPA3116 boards and some TDA7492p. I'm not looking for amazing quality as they are portable battery powered boxes that are generally used when camping or at a party where ambient noise overrides any hiss or "less then perfect" quality. I'm really just looking for a cheap and easy board that can put some volume through an old home stereo speaker.
I would however really like someone to help with my stereo to mono issue. I cant find any modules in mono that compare to the two types I currently have (Sanwu boards).
Currently I have just connected one channel which I realize is not good! Luckily I have not burnt out any boards yet!
I understand I can't mono bridge the TDA7492p but can I with the TPA3116? I am seeing conflicting info online.
I also don't understand whether I can parallel either board/chip? I have seen others ask this question with differing answers (on other websites) or no answer at all. I know this is basic stuff but I feel like I am missing something. Someone please explain how I would run either of these boards in Mono safely, ideally whilst capturing sound from both channels?
If I can't parallel the TDA7492p boards I already have should I put a dummy load on the unused channel? Or given they were ridiculously cheap from ebay should I just make them like before and take my chances?
(Re the speakers as I'm sure someone will comment. I am just using normal budget stereo speakers & I actually don't have any for the next project, the ones I used before were some Sony 6ohm and some Kenwoods which were also 6ohm, mainly because the size was perfect and they were in my garage already...).
Thanks in advance.
Firstly what a fantastic forum, lots of great info here! Actually a little to much info actually as I have spent days and many many hours trolling the pages for info...
I will explain why later but can I first ask a relatively simple (I think?) question?
Can someone kindly summarize the current budget bluetooth capable class D amp boards?
Or more specifically the chips I guess, as I realize that there are many different boards with the same chips.
So now the background on why. I have a little knowledge but admittedly limited. I've always got some project on the go (often electrical) and recently I picked up a TPA3116 board. I grabbed an old speaker and built a portable battery powered bluetooth boombox. It was really popular and I have since built a few more for friends and have requests for more. I have a few TPA3116 boards and some TDA7492p. I'm not looking for amazing quality as they are portable battery powered boxes that are generally used when camping or at a party where ambient noise overrides any hiss or "less then perfect" quality. I'm really just looking for a cheap and easy board that can put some volume through an old home stereo speaker.
I would however really like someone to help with my stereo to mono issue. I cant find any modules in mono that compare to the two types I currently have (Sanwu boards).
Currently I have just connected one channel which I realize is not good! Luckily I have not burnt out any boards yet!
I understand I can't mono bridge the TDA7492p but can I with the TPA3116? I am seeing conflicting info online.
I also don't understand whether I can parallel either board/chip? I have seen others ask this question with differing answers (on other websites) or no answer at all. I know this is basic stuff but I feel like I am missing something. Someone please explain how I would run either of these boards in Mono safely, ideally whilst capturing sound from both channels?
If I can't parallel the TDA7492p boards I already have should I put a dummy load on the unused channel? Or given they were ridiculously cheap from ebay should I just make them like before and take my chances?
(Re the speakers as I'm sure someone will comment. I am just using normal budget stereo speakers & I actually don't have any for the next project, the ones I used before were some Sony 6ohm and some Kenwoods which were also 6ohm, mainly because the size was perfect and they were in my garage already...).
Thanks in advance.
There are a few board makers all with different variations.
The majority of them have the CSR8635 module for Bluetooth. The newer 8645 supports aptx. Apparently it sounds better but I have never tested this. I use cables 95% of the time. The annoying thing is that some boards do one or the other (ie. Bluetooth or 1/8th input but not always both).
There are some new 3116 boards with these modules. I was looking at them since there is one new design with 8645.
The majority of them have the CSR8635 module for Bluetooth. The newer 8645 supports aptx. Apparently it sounds better but I have never tested this. I use cables 95% of the time. The annoying thing is that some boards do one or the other (ie. Bluetooth or 1/8th input but not always both).
There are some new 3116 boards with these modules. I was looking at them since there is one new design with 8645.
If you need mono, just connect your mono source to both channels through something like a 1K resistor per channel.
You won't damage an amp by just using one channel. Class D will just remain silent with no input.
I do like the TAS5630. On a 48V supply it gives a lot more headroom than the TPA3116 on 24V.
Why no stereo with a boombox? Multi channel suits multiple small drivers.
You won't damage an amp by just using one channel. Class D will just remain silent with no input.
I do like the TAS5630. On a 48V supply it gives a lot more headroom than the TPA3116 on 24V.
Why no stereo with a boombox? Multi channel suits multiple small drivers.
Why you want to convert stereo board to mono when there are ready mono tp 3116 board like this DC 12V 24V TPA3116 D2 100W Mono Channel Digital Audio Power Amplifier Board Car | eBay pair it with this seperate bluetooth board you must be ok 12V Wireless Bluetooth MP3 WMA Decoder Board Audio Module USB TF Radio for Car | eBay.
Thanks everyone. I was actually going to edit my initial post but I decided to leave it as is because I think there are lots of people starting out who would like a brief simple summary of these cheap and easy boards. I have done lots of research myself (and have a history/background with electronics though mostly self taught) but i still find myself lost sometimes.
I have a friend in IT who is smart, builds server farms. He wanted to do something similar to me but gave up when he realised he might need to work out additional components etc. The point being is that it wasn't because it was too hard or above him but he simply couldn't be bothered or didn't have the time, he just wanted a plug & play board like the TPA3116 which we both ended up getting together.
So i guess that is why i started this thread, i have other projects on the go but specifically i am here asking about the easy all-in-one budget class D boards & how to mono them or just run one channel.
I decided on the tpa3116d2 and the tda7492p Sanwu boards as they seemed the best but I'm wondering if there are other options in the same category? (Yes my boards both have the CSR8635 bluetooth module, works great. Better & faster connection {initial hookup} than any of my commercial bluetooth audio products!)
Dogshome - the boards i currently own have onboard bluetooth modules so no easy way to mono up the input using resistors. But you say no damage is done just running one channel with load? E.g. left channel has no speaker/load connected.
I have a stereo box i made with salvaged parts. It is great but the idea of these current boxes is simplicity. When i said an 'old home stereo speaker' i probably should have elaborated, i meant the the whole speaker, original casing & all, not just the driver. So they are single wooden box (the left or right speaker from a micro/mini hifi stereo) about 250x150x150mm roughly with a main driver and a tweeter. I turned them on the side with a handle and put battery and amp inside. Basically the easiest/lasiest, cheapest boombox possible! But it is effective.
Angeldust - Yes i had seen that board type (although the one you linked was cheaper thanks). But by the time i buy the amp & the module it is cheaper & easier to just buy a stereo one like i already have. I may go this route for another project but i was considering a mono tda7498.
I'm embarrassed to ask this again but how do i do Mono from either of these boards? I feel like i have skipped a class of highschool physics but i know others have the same question...
1- The TDA7482p is BTL so I can't mono-bridge but i can parallel?
2 - The TPA3116 can be mono-bridged yes?
3 - How do I parallel a stereo output?
(I understand series and parallel obviously and how to parallel speakers etc but how to parallel the amplifier outputs? I found a couple of strange hand drawn schematics a few days back using resistor but it only confused me further. If I simply parallel the connections wont one channel be feeding back into the other channel, surely that can't be good?)
Thanks guys.
I have a friend in IT who is smart, builds server farms. He wanted to do something similar to me but gave up when he realised he might need to work out additional components etc. The point being is that it wasn't because it was too hard or above him but he simply couldn't be bothered or didn't have the time, he just wanted a plug & play board like the TPA3116 which we both ended up getting together.
So i guess that is why i started this thread, i have other projects on the go but specifically i am here asking about the easy all-in-one budget class D boards & how to mono them or just run one channel.
I decided on the tpa3116d2 and the tda7492p Sanwu boards as they seemed the best but I'm wondering if there are other options in the same category? (Yes my boards both have the CSR8635 bluetooth module, works great. Better & faster connection {initial hookup} than any of my commercial bluetooth audio products!)
Dogshome - the boards i currently own have onboard bluetooth modules so no easy way to mono up the input using resistors. But you say no damage is done just running one channel with load? E.g. left channel has no speaker/load connected.
I have a stereo box i made with salvaged parts. It is great but the idea of these current boxes is simplicity. When i said an 'old home stereo speaker' i probably should have elaborated, i meant the the whole speaker, original casing & all, not just the driver. So they are single wooden box (the left or right speaker from a micro/mini hifi stereo) about 250x150x150mm roughly with a main driver and a tweeter. I turned them on the side with a handle and put battery and amp inside. Basically the easiest/lasiest, cheapest boombox possible! But it is effective.
Angeldust - Yes i had seen that board type (although the one you linked was cheaper thanks). But by the time i buy the amp & the module it is cheaper & easier to just buy a stereo one like i already have. I may go this route for another project but i was considering a mono tda7498.
I'm embarrassed to ask this again but how do i do Mono from either of these boards? I feel like i have skipped a class of highschool physics but i know others have the same question...
1- The TDA7482p is BTL so I can't mono-bridge but i can parallel?
2 - The TPA3116 can be mono-bridged yes?
3 - How do I parallel a stereo output?
(I understand series and parallel obviously and how to parallel speakers etc but how to parallel the amplifier outputs? I found a couple of strange hand drawn schematics a few days back using resistor but it only confused me further. If I simply parallel the connections wont one channel be feeding back into the other channel, surely that can't be good?)
Thanks guys.
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Tpa3116. If you leave a channel disconnected then being class d it won't do a lot. You could link the unused input to ground to be doubly certain of if the bluetooth signal is noisy. A tiny amount of soldering to lift a resistor from the Bluetooth module.
So, the other channel is already good for 4 or 8 ohm loads with 21 or 24v supplies respectively. You could therefore use just one channel of that amp happily.
If you want the most oomph into 4 ohms, then you need to do a little soldering to parallel both channels into pbtl.
The amp will work fine with 24v and just one channel, you just won't get the theoretical maximum out of it if using a 4 ohm speaker.
Hope that helps.
So, the other channel is already good for 4 or 8 ohm loads with 21 or 24v supplies respectively. You could therefore use just one channel of that amp happily.
If you want the most oomph into 4 ohms, then you need to do a little soldering to parallel both channels into pbtl.
The amp will work fine with 24v and just one channel, you just won't get the theoretical maximum out of it if using a 4 ohm speaker.
Hope that helps.
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