I need a power amp for some old high power speakers ( as far as I know about 300W each) that I am probably going to get
now I would probably need about 150 to 200W for them and for what I have seen the tda 7294 looks good for that and most importantly cheap and could easily have that much power in some bridge configuration
now I want to know is the bridge circuit in the datasheet ok and could be used?
and how much power do I get in that bridge config with +/- 35V and a 4ohm speaker ?
and how many VA do I need for that is 250VA enough (cause I have that in my lm3886 amp and I was thinking of using that one before I get the money to buy another one as they dont come cheap)
now I would probably need about 150 to 200W for them and for what I have seen the tda 7294 looks good for that and most importantly cheap and could easily have that much power in some bridge configuration
now I want to know is the bridge circuit in the datasheet ok and could be used?
and how much power do I get in that bridge config with +/- 35V and a 4ohm speaker ?
and how many VA do I need for that is 250VA enough (cause I have that in my lm3886 amp and I was thinking of using that one before I get the money to buy another one as they dont come cheap)
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Don't confuse the speaker power rating with the power demand. If you want to use those speakers at home, you will probably need something between 10 and 50 W and only, if you like it really loud.
The bridge circuit in the datasheet is okay. Just check that you have the latest revision of the datasheet.
A BTL amplifier sees half the load, so your 4 Ohm speaker would appear as a 2 Ohm load to each TDA. The datasheet states that the output power is already current limited at ±29 V with a 4 Ohm load. With a 2 Ohm load the current limitation would set in at a lower voltage. Heatsinking will also become difficult.
Why don't you wait until you have the speakers and try them with your LM3886 amp? Then decide, if you really need more power.
The bridge circuit in the datasheet is okay. Just check that you have the latest revision of the datasheet.
A BTL amplifier sees half the load, so your 4 Ohm speaker would appear as a 2 Ohm load to each TDA. The datasheet states that the output power is already current limited at ±29 V with a 4 Ohm load. With a 2 Ohm load the current limitation would set in at a lower voltage. Heatsinking will also become difficult.
Why don't you wait until you have the speakers and try them with your LM3886 amp? Then decide, if you really need more power.
well I already have 8ohm hi-fi speakers at home for the lm3886 amp so at home they are more than enough
I wanted this to have for parties and stuff like that and will probably be used outdoors a lot so I need as much power as I can pump into them
I will probably make just one channel so 2 tda-s cause they cost like 5euor and the resto of the parts 3-4 so for 10 euros I can make ti and use the speakers and power supply that I have so that I can just see how they work and I also want to make something so it looks cheap and interesting
I wanted this to have for parties and stuff like that and will probably be used outdoors a lot so I need as much power as I can pump into them
I will probably make just one channel so 2 tda-s cause they cost like 5euor and the resto of the parts 3-4 so for 10 euros I can make ti and use the speakers and power supply that I have so that I can just see how they work and I also want to make something so it looks cheap and interesting
if you plan on building the Bridge version of the TDA7294 please change the following values from the original data sheet from ST.COM for the :
Bootstrap cap from 22uf to 220uf - better LOW frequency response.
Input cap from 470nF to 4.7uF electrolytic or polyester cap.if you choose electrolytic remember to make sure the +ve pole of the cap faces the input and the -ve pole to pin 3 of the chip.
happy DIYing.
Bootstrap cap from 22uf to 220uf - better LOW frequency response.
Input cap from 470nF to 4.7uF electrolytic or polyester cap.if you choose electrolytic remember to make sure the +ve pole of the cap faces the input and the -ve pole to pin 3 of the chip.
happy DIYing.
I've found this schematic on eagle software database, is it more effiscient or sound better then the recomended datasheet ?
I'm about mount a 5.1 system with this chip, for the bass speaker i'm think to bridge two chips to provide a big woofers, for the rest a simple chip should be perfect,
My question is simple: what is the best schematic for TDA7294? (Power-Distorsion-Quality)? And what do you think about this one?
An externally hosted image should be here but it was not working when we last tested it.
I'm about mount a 5.1 system with this chip, for the bass speaker i'm think to bridge two chips to provide a big woofers, for the rest a simple chip should be perfect,
My question is simple: what is the best schematic for TDA7294? (Power-Distorsion-Quality)? And what do you think about this one?
I wonder what C5 = 4n7F is doing?
It has RF attenuation at the input.
It has DC blocking at the input.
It has a Thiele Network at the output.
It has two stage decoupling on the power pins.
It has mute and standby implemented.
Many of the boxes are ticked.
I'm not sure the switchable unbalanced/balanced is a useful facility.
It has RF attenuation at the input.
It has DC blocking at the input.
It has a Thiele Network at the output.
It has two stage decoupling on the power pins.
It has mute and standby implemented.
Many of the boxes are ticked.
I'm not sure the switchable unbalanced/balanced is a useful facility.
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Ok, thanks for the answer
but i dont understand what do you mean, is it better or worst? What all this aditional stuff are supposed to do or enhance the performance?
That schematic shows a balanced input. It is not better or worse. It is designed for a different application. You will find balanced cables and connectors in professional surroundings like tone studios, PA equipment and in a few so called high-end devices.
If all your sources have balanced outputs, build it. If any of your sources does not have balanced outputs, build the amp as shown in the datasheet.
Ok, thanks for the explaination, so i will not use it, my audio sources are simple and not balanced at all so dont need this method. Finally i will use the datasheet, but have you ant recommandation for the capacitors type? Thanks
I post what i'm doing if it could help anyone:
From the datasheet of cause
And now the PCB:
And
An externally hosted image should be here but it was not working when we last tested it.
From the datasheet of cause
An externally hosted image should be here but it was not working when we last tested it.
And now the PCB:
An externally hosted image should be here but it was not working when we last tested it.
And
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
Hope its could be helpfull
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