Class D Amplifier

[rockingx]

Hello Experts,

Wanted to know your opinion on Class D single board amplifier quality.

- How is the sound quality of Class D single board amplifier?
- I found the following mono board:
Brand: Eight Audio
Part No: EADA04
Description: Welcome to use this 1 X 100 watts at 2 Ohm Class D audio amplifier board. It integrates TI’s high performance TPA3116 chip supporting mono amplification by using PBTL topology. The premium Quality electronic components like Coilcraft Inductors, Nichicon Audio grade capacitors, AVX SMD capacitors and Yageo thick film resistors are used in this highly efficient amplifier board create a powerful 2 channel & Audiophile Quality.
Specifications:
Manufacturer: Eight Audio
Power output @ 2 ohmsL 100w, Vcc= 21V DC
Minimum impedance: 2 ohms
Frequency response: 20 - 22 Khz
Operating supply voltage: 8 V to 24 V

- Specification says 100W, however I don't think this poor think can pump up this much?



- I think 2 x these boards can be used to built a simple basic stereo amplifier, each board amplifying each stereo channel?
- To power up both the boards, 20-24V DC would be appropriate? May be a laptop charger? or smps?

Something like this?


- Do you think it will work? If yes then may be a small foot print stereo amplifier within 3 - 3.5K with super simple DIY effort can be done

Please share your thoughts....

Thanks in advance

 

[vipulpatel]

From the rating of the SMPS it is 24V with max 2.5A. So this SMPS can deliver max 24V*2.5A=60W of power. i.e. 30W per channel. That needs to be taken into consideration along with many other things like how clean will be the power form this source.

 

[rockingx]

From the rating of the SMPS it is 24V with max 2.5A. So this SMPS can deliver max 24V*2.5A=60W of power. i.e. 30W per channel. That needs to be taken into consideration along with many other things like how clean will be the power form this source.

Thanks Vipul, specifications says "Power output @ 2 ohmsL 100w, Vcc= 21V DC":
- doesn't it mean that 100W from 21V DC input?

Specifications says "Operating supply voltage: 8 V to 24 V::
- so power supply should be rated on or below 24V?

As one power supply would power up both the boards, what should be the ideal rating of supply for these boards?

 

[vipulpatel]

"- doesn't it mean that 100W from 21V DC input?" this means the amp can provide this much power to the speaker from its output. But the same power is to be drawn from the supply plus some losses. So if the requirement is e.g 50W per channel and voltage selected to be used is 21V then the current rating for the smps should be 50/21=2.3A. But again this is for single channel. For 2 channels it will required 2.3*2=6.6A. Hence, if you decide to drive both boards with same supply and design for an output of 50W per channel then you will need a supply with ratings 21V , 6.6A atleast.

 

[rockingx]

"- doesn't it mean that 100W from 21V DC input?" this means the amp can provide this much power to the speaker from its output. But the same power is to be drawn from the supply plus some losses. So if the requirement is e.g 50W per channel and voltage selected to be used is 21V then the current rating for the smps should be 50/21=2.3A. But again this is for single channel. For 2 channels it will required 2.3*2=6.6A. Hence, if you decide to drive both boards with same supply and design for an output of 50W per channel then you will need a supply with ratings 21V , 6.6A atleast.

You made it simple to understand... thanks.

So, following power supply can safely be used?

1) For 40-50W per channel/board => 24V 5A SMPS - 120W
2) For 80-100W per channel/board => 24V 10A SMPS - 240W <<will it be safe to put this one?>

I see that manufacturer specification says 100W @ 2 ohm, so it should be around 40-50W @ 8 ohm?
If i am using 8 ohm speakers then "24V 5A SMPS" should be good enough?

I also read somewhere that smps adds noise to the signal?

Any comments on the sound quality of this specific board if anyone used? or class D cheap board amplifiers like this one?

 

[SanjeevM]

This is a TPA3116 based board. Sound should be good. The chip is basically a stereo chip, but in this board it is being run in PBTL mode to give 100W power Mono into 4 ohm speakers. Absolute max voltage is 26V, so practical voltage for max power is 24V. Then it should draw 4.1 Amps per channel. If you are keen on making a Amp which gives 100W x 2, then you must get a 240W power supply.

However, so much power is not needed, so a smaller PSU will do. It is better if you get a 24V PSU. You can get many SMPS modules from eBay or your local electronics market. For example:

https://www.flipkart.com/sunrobotic...e0vrxs6b4jr41534259009066&qH=e83df33a78711ae5

 

[guddu478]

This is a TPA3116 based board. Sound should be good. The chip is basically a stereo chip, but in this board it is being run in PBTL mode to give 100W power Mono into 4 ohm speakers. Absolute max voltage is 26V, so practical voltage for max power is 24V. Then it should draw 4.1 Amps per channel. If you are keen on making a Amp which gives 100W x 2, then you must get a 240W power supply.

However, so much power is not needed, so a smaller PSU will do. It is better if you get a 24V PSU. You can get many SMPS modules from eBay or your local electronics market. For example:

https://www.flipkart.com/sunrobotic...e0vrxs6b4jr41534259009066&qH=e83df33a78711ae5

Thanks Sanjeev, much appreciated.
Another thing I want to know is if it is possible to add volume control with this board, details mentioned did not give enough details.
Can anyone put some light on?

 

[Kannan]

I am using this board to power the subwoofer in my car which is an isobaric design wired in parallel for 2 ohms load.
It pumps out loads of power.
I however did not like it on either my midbass or the midrange fir which I am using 3118d2 based amps

 

[somakmaitra]

Hi
I have used a 50w ×2 and 100w ×2 of the tpa3116d2 . The 100watt amp was dissapointing as the output was low when directly driven from smartphones. The 100w is a PBTL mode amp while 50w is a BTL mode one . The 50w ×2 was really awesome amp. An it cost peanuts so you lose nothing as such .I bought the board from aliexpress .I would recommend you to buy this amp Ba100 as it has a preamp and has got very good reviews
Regards
Somak

 

[rockingx]

Thank you guys for your inputs, its really helpful.

 

[jls001]

Thanks Sanjeev, much appreciated.
Another thing I want to know is if it is possible to add volume control with this board, details mentioned did not give enough details.
Can anyone put some light on?

Put a stereo pot at the input. 10 kOhms is good. Check out theaudiocrafts.com for a good selection of stepped pots.

Not heard a 3116 but I love the lower power PBTL 3118.

 

[SanjeevM]

Well, I have a spare TPA3116d2 board. The sound output of this board is very good. Please PM me if you need it.

 

[surfatwork]

Put a stereo pot at the input. 10 kOhms is good. Check out theaudiocrafts.com for a good selection of stepped pots.

Make sure you get a 10k logarithmic stereo pot