Hello all.
I am posting after a long time . First i am a complete noob on this amplifier thing.
2nd sorry if i did/about to do any mistake out of my lack of knowledge. I intend to buy this particular tda 7293 board because it is cheap and convenient.
100W Digital Power Amplifier Board TDA7293 / 7294 High Power Dual 12-32V Single Channel Audio Amplifier Module for DIY Speaker
a.aliexpress.com
My subwoofer is a 75w RMS old Philips one.
Can i drive it optimally with it?
I intend to run this amp with a 35-0-35 VAC EI transformer (yep i am mr. Cheap 😛 ). One of the top most priorities is to keep it economical .
Other options:
1. Tda8954th btl mode
2. STK 4048
PLZ help
I am posting after a long time . First i am a complete noob on this amplifier thing.
2nd sorry if i did/about to do any mistake out of my lack of knowledge. I intend to buy this particular tda 7293 board because it is cheap and convenient.
100W Digital Power Amplifier Board TDA7293 / 7294 High Power Dual 12-32V Single Channel Audio Amplifier Module for DIY Speaker
3.62US $ 18% OFF|100W Digital Power Amplifier Board TDA7293 / 7294 High Power Dual 12 32V Single Channel Audio Amplifier Module for DIY Speaker|Operational Amplifier Chips| - AliExpress
Smarter Shopping, Better Living! Aliexpress.com
My subwoofer is a 75w RMS old Philips one.
Can i drive it optimally with it?
I intend to run this amp with a 35-0-35 VAC EI transformer (yep i am mr. Cheap 😛 ). One of the top most priorities is to keep it economical .
Other options:
1. Tda8954th btl mode
2. STK 4048
PLZ help
In my experience chipamps don't sound very good in the bass, I've had better subjective results with classD. Try an IRS2092 board and stiffen the power supplies to the IRS2092 chip itself. It'll likely be more expensive than a chipamp board but you'll not need so large a heatsink.
Something like this : https://www.aliexpress.com/item/32996063868.html
Something like this : https://www.aliexpress.com/item/32996063868.html
Thanks a lot mate.
Intact after seeing your post i have ordered one just now. But i have done some homework on IRS2092 for sometime.
My problem is i can't find the minimum voltage it needs to operate. Some board says dual dc 45 v, some say 30v.
Another thing is what power voltage do i need to get 100w output i couldn't quite fathom on this mono amp beast. Pardon my illiteracy on this matter.
Good question about the minimum voltage. Fortunately that's normally set by zeners and/or resistors external to the chip.
I'm not certain but its likely the board I linked is based on IR's IRAUDAMP7 reference design, user manual here : https://www.infineon.com/dgdl/iraudamp7d.pdf?fileId=5546d462533600a40153569ad5ba2bf9
If you go to fig35 the UVP (under voltage protection) is set by zener Z101 (39V). You just have to figure out where that is on your board and change it to something lower. Assuming you do indeed want lower, for 100W/8R its probably fine at ~39V.
To get 100WRMS into 8R you need Sqrt(800) volts (RMS) which is 28.3. That's 40V peak, hence (allowing for some loss) +/-43V would be your supplies.
I'm not certain but its likely the board I linked is based on IR's IRAUDAMP7 reference design, user manual here : https://www.infineon.com/dgdl/iraudamp7d.pdf?fileId=5546d462533600a40153569ad5ba2bf9
If you go to fig35 the UVP (under voltage protection) is set by zener Z101 (39V). You just have to figure out where that is on your board and change it to something lower. Assuming you do indeed want lower, for 100W/8R its probably fine at ~39V.
To get 100WRMS into 8R you need Sqrt(800) volts (RMS) which is 28.3. That's 40V peak, hence (allowing for some loss) +/-43V would be your supplies.
Sadly i can't do any soldering of any sort right now. 🙁
So IIRC u using p= v²/r. But i have some confusion regarding this, plz again forgive me for being such a noob.
If the desired voltage is 28.3V .. why 40V?
Ohhh. Because 28.3V is the desired RMS voltage. I see. So 28.3v x1.4=40v.
Now , i intend to drive this amp with 24v-0-24v AC thru rectifier filter board. That is the problem bro. 🙁. So i will be getting only +-34v only :*
I am getting confused again. U said the amp board will not switch on with any voltage lower than 39v . So isnt 30v is a problem
Yes indeed bro. 🙁 damn. I need to learn soldering . And changing the zener diode will do the trick right?
It looks like it would take minimum a month to arrive to my country. 🙁 .
Long time wait . While waiting for that irs i can order a locally available tda7293 for only 7$ and tinker with it to make the wait a little less boring. The very board i have mentioned in the opening post.
The board says max 32-0-32 VAC . but i have two options only. Either 24-0-24VAC or 35-0-35VAC transformer. I will be using rectifier filter board anyway.
My question is as 24vac will be too weak for my 8 ohm system will 35vac be risky for this board? What will be the amount of voltage drop if i use a power rectifier filter board ?
On this TDA7293 board Filter caps are 50v
Rectifier is kbl608.
Long time wait . While waiting for that irs i can order a locally available tda7293 for only 7$ and tinker with it to make the wait a little less boring. The very board i have mentioned in the opening post.
The board says max 32-0-32 VAC . but i have two options only. Either 24-0-24VAC or 35-0-35VAC transformer. I will be using rectifier filter board anyway.
My question is as 24vac will be too weak for my 8 ohm system will 35vac be risky for this board? What will be the amount of voltage drop if i use a power rectifier filter board ?
On this TDA7293 board Filter caps are 50v
Rectifier is kbl608.
35-0-35V is very likely to over-voltage the chip. If I were you I'd settle for lower power and choose the 24-0-24V transformer. You haven't mentioned the VA rating of this trafo so far have you? If its 150VA or less then the higher voltage one will be severely current-starved leading to a very saggy supply.
Bro.. i getting confused again. Let me get the weight of these two and get the measurement if possible and let u know.
(I don't know how many times it is appropriate to apologise for me being noob. So again apologising for apologising too much 😜 Sorry. )
The cheap TDA7293 board you showed in your initial post is a DIYS kit. You have to solder it. So maybe time to consider to upgrade on tools and buy a soldering iron and a reel of 0,8-1mm solder. If you do so, 25W are more than enough for such "trough hole" electronics.
Better are adjustable irons, like these:
https://www.aliexpress.com/item/1005003843715422.html?spm=a2g0o.productlist.0.0.32c559f2EpuBgV&algo_pvid=56ebc77e-484d-40cc-9d87-6b192a8b4a3b&algo_exp_id=56ebc77e-484d-40cc-9d87-6b192a8b4a3b-5&pdp_ext_f={"sku_id":"12000027319837041"}&pdp_npi=2@dis!EUR!!4.15!!!1.5!!@2100bdd516553477924842895e9703!12000027319837041!sea
If you go for SMD, like on the class D amp, this is already too much. If you are experienced in soldering electronics, you may be able to change a single (if it is relative large, they come in different sizes!) SMD part with such an iron too. You need a very good eye and steady hands for that.
The class D mentioned, should work on 30-60 V, your 35-0-35V AC transformer should give 50-0-50V DC after rectifier + capacitors and work without changing the Zener.
These Chinese amp modules usually come without any instructions, the seller has no clue what this part is and does not speak usable English, so don't expect any kind of help there. For Chinese crooks a transaction is finished after they got your money. Even the description on Ali is usually BS as you can see here:
"100% brand new, high quality With original IRS2092, IRFI4019 Adopting the internationally renowned brand electrolytic circuit signal main circuit, adopting Nikon capacity 330UF / 100V * 2, main filter capacitor to ensure continuous power supply Resistant breeding 08050603 high-precision chip resistors to ensure a good signal-to-noise ratio of the whole machine With a double-sided PCB 2.0 ounces of pure copper thickness, the entire process of spraying tin is 1.6 mm thick to ensure good current through the performance. PCB quality
Use 20A high current shielding inductor to ensure a crisp and powerful sound Very small size and high power"
This is all the information you get from China, part useless, part wrong. Live or die with it...
You can buy from such sources if you are willing to take a risk and know what you do or follow the advice from a friendly diyAudio member extreme closely.
Better are adjustable irons, like these:
https://www.aliexpress.com/item/1005003843715422.html?spm=a2g0o.productlist.0.0.32c559f2EpuBgV&algo_pvid=56ebc77e-484d-40cc-9d87-6b192a8b4a3b&algo_exp_id=56ebc77e-484d-40cc-9d87-6b192a8b4a3b-5&pdp_ext_f={"sku_id":"12000027319837041"}&pdp_npi=2@dis!EUR!!4.15!!!1.5!!@2100bdd516553477924842895e9703!12000027319837041!sea
If you go for SMD, like on the class D amp, this is already too much. If you are experienced in soldering electronics, you may be able to change a single (if it is relative large, they come in different sizes!) SMD part with such an iron too. You need a very good eye and steady hands for that.
The class D mentioned, should work on 30-60 V, your 35-0-35V AC transformer should give 50-0-50V DC after rectifier + capacitors and work without changing the Zener.
These Chinese amp modules usually come without any instructions, the seller has no clue what this part is and does not speak usable English, so don't expect any kind of help there. For Chinese crooks a transaction is finished after they got your money. Even the description on Ali is usually BS as you can see here:
"100% brand new, high quality With original IRS2092, IRFI4019 Adopting the internationally renowned brand electrolytic circuit signal main circuit, adopting Nikon capacity 330UF / 100V * 2, main filter capacitor to ensure continuous power supply Resistant breeding 08050603 high-precision chip resistors to ensure a good signal-to-noise ratio of the whole machine With a double-sided PCB 2.0 ounces of pure copper thickness, the entire process of spraying tin is 1.6 mm thick to ensure good current through the performance. PCB quality
Use 20A high current shielding inductor to ensure a crisp and powerful sound Very small size and high power"
This is all the information you get from China, part useless, part wrong. Live or die with it...
You can buy from such sources if you are willing to take a risk and know what you do or follow the advice from a friendly diyAudio member extreme closely.