Any full-bridge board. Most big boards can comfortably operate from a 24V supply. If everything else is OK, the max power is limited mainly by the load impedance and supply voltage.
I need a MONO class d amp board with a small footprint max. 3 x 4 x 1.2" and only have max 24V 6A (not +/-) that can deliver "200w". TPA3116D2 is not powerfull enough at 24V.
I guess there is a fundamental thing I don't understand about class d amplifiers; do you get higher gain/efficiency (without distortion) if you step up the voltage (but thus lowering the current) ?
The fundamental thing about amplifiers (A,B,AB,H,D-class) is the Ohms law. So if you have a given impedance of 4 Ohm and a given voltage of 24 Volt, you will only get a maximum current in Ampere. As power basically is VxA=W you have to increase the voltage or lower the impedance.
So 24V AC are 17V RMS
17 squared are 290
Divided by 4 Ohm gives you around 70W
so with 2 Ohm, theoretically you double the output.
Theory is a good thing, but in reality you do not get all the Volt to your voice coil. Diodes, transistors and resistances are in the voltages way. So instead of guessing, we look at the data sheet. Anything you want (not) to know is found in it.
The best option you have is to get a TBA3116 which is running in PBTL mode, which means two amps bridged (as usual with these chips) and two of those in parallel. As one 3116 has 4 amp channel on board, it needs one chip for mono and two chips four stereo. They can give up to 120W, but only at 2 Ohm!
There are a few real PBTL versions of this chip out there. This is one that worked well in the past
https://www.ebay.de/itm/401614836334
but don't fall for a similar looking 2x120W version!
It is quite easy to take two 4 Ohm speakers and parallel them to get 2 Ohm, by the way.
Now we look at the data sheet, page 11: https://www.ti.com/lit/ds/symlink/tpa3116d2.pdf?ts=1667710563515
and find that with 24V and 2 Ohms, the chip has a maximum output with 1% distortion of 120W. With 10% THD, which may be usable for short burst sub woofer use, even 150W are promised, if anything is made perfect around the chip. Keep that in mind!
For 4 Ohms the numbers are 60 and 75W, as you already know from Ohms law.
How comes these amps are advertised at 2x 120W and more? Because you can write anything you like, in an add, if you are Chinese. (Don't write about human rights if you are Chinese!)
So for your 24 Volt source with 200W /6A you can make a lot of noise. In real life, a 200W supply can drive two 150W amps without a problem (look crest factor).
The 3116 has an excellent sound and an unbeatable price/ sound ratio. You will rarely ever find a better sounding A/B amp of similar power when you look at amps from the past and stay objective.
If you have a look at these four small output coils that are used on the board I linked, something larger would fit 120 watt per channel much better.
I ignore this, because you only use a fraction of the theoretical power while hearing music. If you constantly hear distortion on high levels, changing them for something larger could be an option. Which is not recommended for beginners, as playing with SMD parts will ruin the PCB quite easily. Also, the parts will be much more expensive than the whole amp...
Good luck!
So 24V AC are 17V RMS
17 squared are 290
Divided by 4 Ohm gives you around 70W
so with 2 Ohm, theoretically you double the output.
Theory is a good thing, but in reality you do not get all the Volt to your voice coil. Diodes, transistors and resistances are in the voltages way. So instead of guessing, we look at the data sheet. Anything you want (not) to know is found in it.
The best option you have is to get a TBA3116 which is running in PBTL mode, which means two amps bridged (as usual with these chips) and two of those in parallel. As one 3116 has 4 amp channel on board, it needs one chip for mono and two chips four stereo. They can give up to 120W, but only at 2 Ohm!
There are a few real PBTL versions of this chip out there. This is one that worked well in the past
https://www.ebay.de/itm/401614836334
but don't fall for a similar looking 2x120W version!
It is quite easy to take two 4 Ohm speakers and parallel them to get 2 Ohm, by the way.
Now we look at the data sheet, page 11: https://www.ti.com/lit/ds/symlink/tpa3116d2.pdf?ts=1667710563515
and find that with 24V and 2 Ohms, the chip has a maximum output with 1% distortion of 120W. With 10% THD, which may be usable for short burst sub woofer use, even 150W are promised, if anything is made perfect around the chip. Keep that in mind!
For 4 Ohms the numbers are 60 and 75W, as you already know from Ohms law.
How comes these amps are advertised at 2x 120W and more? Because you can write anything you like, in an add, if you are Chinese. (Don't write about human rights if you are Chinese!)
So for your 24 Volt source with 200W /6A you can make a lot of noise. In real life, a 200W supply can drive two 150W amps without a problem (look crest factor).
The 3116 has an excellent sound and an unbeatable price/ sound ratio. You will rarely ever find a better sounding A/B amp of similar power when you look at amps from the past and stay objective.
If you have a look at these four small output coils that are used on the board I linked, something larger would fit 120 watt per channel much better.
I ignore this, because you only use a fraction of the theoretical power while hearing music. If you constantly hear distortion on high levels, changing them for something larger could be an option. Which is not recommended for beginners, as playing with SMD parts will ruin the PCB quite easily. Also, the parts will be much more expensive than the whole amp...
Good luck!
Neither TPA3116D2 nor any other amplifier can deliver anything even remotely approaching 200W into 4 ohm at mere +24V supply.
Simply because maximum peak voltage available is about 22V (semiconductors always drop a little voltage, at least 1V ... and you have 2 in series) so maximum available is 15.5V RMS .... so 60W RMS into 4 ohm.
Power amps of any kind do not create power, only supply and throttle some (depending on efficiency) of what´s available at the power supply.
Here is a very rare beast, with two 3116 in PBTL mode:
https://www.amazon.de/DollaTek-Digi...19-8b40-05d5ef5f146d&pd_rd_i=B07KPSYHWF&psc=1
From experience, out of the box it will sound OK, but if you change the fake NE5532 opamp for a real NE5532, it will sound really great. You only have to attach your power supply and have a nice amp, much cheaper than building it by your self. Here Breeze did one good amp at last.
PS notice the well sized output coils!
https://www.amazon.de/DollaTek-Digi...19-8b40-05d5ef5f146d&pd_rd_i=B07KPSYHWF&psc=1
From experience, out of the box it will sound OK, but if you change the fake NE5532 opamp for a real NE5532, it will sound really great. You only have to attach your power supply and have a nice amp, much cheaper than building it by your self. Here Breeze did one good amp at last.
PS notice the well sized output coils!
OSLO, I suggest that you pay attention to what JMFahey said above. The theoretical maximum for 24V BTL into 4 ohms is (24^2)/2/4 = 72W (only).
Also, 24V*6A is by itself only 144W. For 200W, you'd need voltage and current capabilities approaching 15VRMS and 15ARMS respectively. That is, you need to reduce the load impedance to something like 1 ohm (4 x 4-ohm woofers).
Also, 24V*6A is by itself only 144W. For 200W, you'd need voltage and current capabilities approaching 15VRMS and 15ARMS respectively. That is, you need to reduce the load impedance to something like 1 ohm (4 x 4-ohm woofers).
I love it when everyone repeats what I wrote 3 posts above.
Anyway, OSLO did not ask for 200 W output, but mentioned to have a 200W power supply.
He did not understand how Volt and Watt stuff worked and is calculated.
Please don't blame me for that, but his physic's teacher.
Fast reading is an wonderful art, but sometimes does not get the whole picture...
Anyway, OSLO did not ask for 200 W output, but mentioned to have a 200W power supply.
He did not understand how Volt and Watt stuff worked and is calculated.
Please don't blame me for that, but his physic's teacher.
Fast reading is an wonderful art, but sometimes does not get the whole picture...
OK. Thanks. I think I will go for TPA3116D2 (is that the same as TPA3116DA that some adventise?) Does having an onboard 5532 Op amp make a difference or not (like https://www.amazon.de/Agatigex7vhye52ka/dp/B0BKT5LJBV/) ?
BTW I am going to add a small BT AptX HD TWS Partymode module to it. What is the easiest way to get 5V for it ?
BTW I am going to add a small BT AptX HD TWS Partymode module to it. What is the easiest way to get 5V for it ?
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To return to your original question, the highest power classD chip I know of running from 24V delivers typically 150W into a 1ohm load : https://www.nxp.com.cn/docs/en/data-sheet/TDF8599B.pdf. I've not seen any boards using it mind.
As per the datasheet, the TDA7298E can put out roughly 90W in BTL configuration @ 3 Ω and 1% THD with a 24 Vdc supply. Please judge by yourself if this suffices you. For more power, you might want to look for a chip that is capable to drive 2 Ω at the same conditions.
Best regards!
All TPA3116D2 (full name,) boards with an additional "booster" OP-amp, have been reported to be very noisy. Removing the op amp improved the performance.
The 3116 chip usually does not need them, as your preamp or CD-Player supplies enough input level for it's input stage.
The problem I see is that hardly all Chinese NE5532 op amps are fake and in most cases even worse than a TL072 or other antique, low cost chip. 50 Cent saved compared to a real parts is a lot of money in China.
Changing them for a real, European bought NE5532's then miraculously improves the sound.
The board you liked has it soldered, not on a socket, so changing gets quite difficult. In reality these are tiny! It does not have more power than any other 3116 PBTL.
Why don't you just pick the board I linked? It has been found to sound very good, by members of this forum in the endless 3116 threads.
For 5 V simply buy a small, adjustable regulator board (1-2$) and connect it to your 24V. Then carefully adjust it. Like these:
https://www.amazon.de/ANGEEK-LM317-...rds=regulator+board+317&qid=1667826740&sr=8-2
PS the TDA7498E In PBTL Mode does not have more power than the TPA3116D2 in the same configuration, if supplied with 24V.
While the TDA7498E is not recommended for less than 3 Ohm, the 3116 is happy with 2 Ohm. Don't ask me why, read the data sheet...
The 3116 chip usually does not need them, as your preamp or CD-Player supplies enough input level for it's input stage.
The problem I see is that hardly all Chinese NE5532 op amps are fake and in most cases even worse than a TL072 or other antique, low cost chip. 50 Cent saved compared to a real parts is a lot of money in China.
Changing them for a real, European bought NE5532's then miraculously improves the sound.
The board you liked has it soldered, not on a socket, so changing gets quite difficult. In reality these are tiny! It does not have more power than any other 3116 PBTL.
Why don't you just pick the board I linked? It has been found to sound very good, by members of this forum in the endless 3116 threads.
For 5 V simply buy a small, adjustable regulator board (1-2$) and connect it to your 24V. Then carefully adjust it. Like these:
https://www.amazon.de/ANGEEK-LM317-...rds=regulator+board+317&qid=1667826740&sr=8-2
PS the TDA7498E In PBTL Mode does not have more power than the TPA3116D2 in the same configuration, if supplied with 24V.
While the TDA7498E is not recommended for less than 3 Ohm, the 3116 is happy with 2 Ohm. Don't ask me why, read the data sheet...
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The problem is precisely that I hear constantly distortion above 70% with the current "100w" setup. I could limit the gain/volume, but I want to be able to also play loud. I have ordered the board you suggested (without op amp) for test (I assume this is the same board https://www.amazon.de/-/en/gp/aw/d/B0834XJCJG?ref=ppx_pt2_mob_b_prod_image).
The bluetooth board only use 20 mA, so perhaps I could use something smaller.
BTW is TPA3116D2 and TPA3116DA the same ?
The bluetooth board only use 20 mA, so perhaps I could use something smaller.
BTW is TPA3116D2 and TPA3116DA the same ?
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Your speakers impedance rises below 150Hz. That is why your 24V amp gets exhausted. The new board may do a little better, but do not expect too much.
With such speakers you should use an amp that puts out clean 200W/4ohm. Such an amp can drive your bass driver, even when it's impedance goes higher than 4 ohm, like 15 ohm around 90 Hz. Such an Amp will need dual 50 Volt at least or a single supply of 50V when it is bridged.
If you read my previous post's: You only get 120 Watt at 2 Ohm with the PBTL 3116 (TDA3116, forget the D2 or what ever). The "normal" bridged 3116 will shut down at 2 Ohm load.
With such speakers you should use an amp that puts out clean 200W/4ohm. Such an amp can drive your bass driver, even when it's impedance goes higher than 4 ohm, like 15 ohm around 90 Hz. Such an Amp will need dual 50 Volt at least or a single supply of 50V when it is bridged.
If you read my previous post's: You only get 120 Watt at 2 Ohm with the PBTL 3116 (TDA3116, forget the D2 or what ever). The "normal" bridged 3116 will shut down at 2 Ohm load.
Keep in mind that 70 watts is at clipping. If music dynamics are considered 10watts is more likely. I find that amps with analog power meters are clipping when the meters indicate as low a 1/10th the clipped power.
Then simply your amplifier is not powerful enough, period.
In good English, you need a more powerful amplifier (50-200W RMS?) fed from a higher voltage supply.
Forget 24V supplies, forget TPA311x
To boot, your speaker system is neither efficient (~85dB per those curves) nor 4 ohm, it hovers around 5 ohm most of the time; personally I would call it a 6 ohm speaker, so best case it can pull some 40W RMS from that supply.
Again shown in those curves.
You can´t expect different results if parameters stay the same: 24V supply - bridged Class D amplifier - 6 ohm speaker - 85dB efficiency.
Not a bad system for home use, huh? , incredibly flat and extended frequency response, flat impedance is a bonus, but not wall shaking by any means.
Try for a 200W RMS into 6 ohm amp and we are talking.