Thats alright, and yes the NUMBERS represent the pins on the TDA7294/3, if you have seen the pictures of the "circuit"/hole print you can see that there are pins missing from the chip, those are the 5, 10, 11, i just bend them back and forth a few times and they break off
NOTE in TDA7293 pin 12 is in use so if you are making the TDA7293 then don't break off that pin.
Thanks for that , total brain fart there lol.
So im assuming the powersuppy is also included directly on the circuit so i can just plug the transformer str8 to the board?
Just to let you know , im planning to use these to power the PA system im in the process of building i will be posting up full pictures of everything, including a redesign of the classic 18" Superscooper wich i have shrunk down to 8" versions for home use- sounds great
So im assuming the powersuppy is also included directly on the circuit so i can just plug the transformer str8 to the board?
Just to let you know , im planning to use these to power the PA system im in the process of building i will be posting up full pictures of everything, including a redesign of the classic 18" Superscooper wich i have shrunk down to 8" versions for home use- sounds great
Well the power-supply needs to be done also, you can throw 20-45V +/- directly on this AMP, a note on wiring thou, main power wires needs to be connected to the Transistors from here you don't need very thick wire going to the board after.
If you use a Ring-Transformer then remember to make the normal power things, A good Bridge Rectifier and some good caps, you should use a minimum 2x10,000uF (50V/63V), anything over will always be better.
If you use a Ring-Transformer then remember to make the normal power things, A good Bridge Rectifier and some good caps, you should use a minimum 2x10,000uF (50V/63V), anything over will always be better.
I found this diagram designed for the TDS but at 50w rms
Free Schematic Diagram at www.circuitdiagram.net
could i adjust this plan to get the output high enuf to get 300/400 watts out of the amp?
Free Schematic Diagram at www.circuitdiagram.net
could i adjust this plan to get the output high enuf to get 300/400 watts out of the amp?
Thats a good diagram, just use a different transformer:
For 4-8Ohm using 300W (MAX) speakers use a 150VA 2x30V
For 2-4Ohm using 500W (MAX) speakers use a 300VA 2x30V
If you plan on using Dual Transistors and also bridge then you need a 500VA+ Transformer.
And the caps again have to be 50V or 63V, you can also omit the 2x 2.2K resistors and Diodes (last component set in the diagram)
Again the AMP is setup for 2-8Ohm LOAD, you have to change/experiment with another resistor then the 6.8Ohm for less then 2 Ohm, it will drive 1Ohm with no problems but there will be noise introduced if the Resistor is not changed.
if 30v to 55v is the AC rating (like 230V - 2x30V/300VA) then DO NOT go over 30V, the next AMP im making (TDA7293) will go higher but the TDA7294 will only take MAX 2x50V DC, again DC and if you take 30V AC and multiply it with 1.41 then you get 42,3V DC.
AGAIN DO NOT go beyond 30V AC, you will fry the TDA7294, there are ways to archive LIMIT VOLTAGE with an INPUT over 50V but from the latest post you are a bit of a noob so lets keep it simple and to the point.
Nothing wrong with being a noob, we all where at the beginning
, and im glad to help where i can.Nothing wrong with being a noob, we all where at the beginning
Your damn right! lol
No one steps into a new task a pro =)
Thanks for that n wish me luck =D
Can't say anything about the measured result, all i can say is that this amp is the one i have that have the LEAST distortion in what you hear, and this is up against more amps than i can count, as i said 15+ years in the field so far, also i use to UPGRADE commercial amps, and we are not talking the cheap brands here.
But that said, if anybody here makes it and gets it measured then that would be cool, i don't have access or the TIME to do this, seriously have to make time just to reply here.
Will say again, this AMP is the best i have ever had in my arsenal of audio equipment.
No you can't, every AMP that is not in BTL can only be bridged one time, would be awesome if you could bridge it again thou.
But the TDA7294 gives out some serious watt's in 4-8Ohm when bridged, TDA7293 will of course give even more since it will take 10V +/- more, a DUAL SET Transistors pr AMP and then bridge them (TDA7293) and you can achieve up to 1500W (MAX) in 8 Ohm, and 2500W - 3000W (MAX) in 4 Ohm.
This will of course require some SERIOUS POWER at the input side, 8 Ohm you can do with a 1000VA 2x40V Ring-Transformer and of course a GOOD amount of capacitors >50,000uF
The most you can get out of any amplifier(a little less due to the voltage drop across the output devices) with +/- 50v supply rails into 8 ohms is 156.2 watts.
Into 4 ohms this is 312.4 watts.
Therefore in a bridged (BTL) configuration this becomes 624.8 watts into 8 ohms.
At this level each transistor has to supply 17.675 amps to the load.
Lets assume for the above example that the rails are +/- 55volts (although this is over what the power opamp is rated for)and the output voltage was +/- 50v, then each transistor has to dissipate (55-50) volts*(17.675) amps= 88.375 watts per output device.
Although this is well below the power rating of the transistor, 17.675 amps is over the rated maximum current handling of 15 amps for the transistors.
Therefore it is suggested that two pairs should be used in each leg of the amplifier as well as a single one running into 4 ohms to be within the safe limits of the output devices.
In order to run this amp Bridged (BTL) into 4 ohms at 1025.6 watts, or, a single amp at 2 ohms at 624.8 watts a minimum of 4 pairs of output devices should be used on each TDA729X power opamp.
It is possible you could get more power, But Only, By using a lower impedance load and to do this you would either have to double the output pairs again or use a Paralleling technique as commonly done with chip amps and at this point stability problems could become an issue.
I do plan on getting the parts to try one of these and put it to some rigorous tests, sometime this summer though.
This technique is used to boost the current output of opamps and I have seen it used in small to medium powered amplifiers as well and headphone amps, But never one with this power capability configuration.
Cheers !!!
jer
P.S. It is very interesting and is a configuration that I myself had thought about for many years using a LM383 and a 2N3055 and 2N2955 but never got around to trying it.
National semiconductor has documented this type of amp using a LM377 and a pair of complimentary transistors in the 15 to 20 watt range back in the late 70's and early 80's.
Into 4 ohms this is 312.4 watts.
Therefore in a bridged (BTL) configuration this becomes 624.8 watts into 8 ohms.
At this level each transistor has to supply 17.675 amps to the load.
Lets assume for the above example that the rails are +/- 55volts (although this is over what the power opamp is rated for)and the output voltage was +/- 50v, then each transistor has to dissipate (55-50) volts*(17.675) amps= 88.375 watts per output device.
Although this is well below the power rating of the transistor, 17.675 amps is over the rated maximum current handling of 15 amps for the transistors.
Therefore it is suggested that two pairs should be used in each leg of the amplifier as well as a single one running into 4 ohms to be within the safe limits of the output devices.
In order to run this amp Bridged (BTL) into 4 ohms at 1025.6 watts, or, a single amp at 2 ohms at 624.8 watts a minimum of 4 pairs of output devices should be used on each TDA729X power opamp.
It is possible you could get more power, But Only, By using a lower impedance load and to do this you would either have to double the output pairs again or use a Paralleling technique as commonly done with chip amps and at this point stability problems could become an issue.
I do plan on getting the parts to try one of these and put it to some rigorous tests, sometime this summer though.
This technique is used to boost the current output of opamps and I have seen it used in small to medium powered amplifiers as well and headphone amps, But never one with this power capability configuration.
Cheers !!!
jer
P.S. It is very interesting and is a configuration that I myself had thought about for many years using a LM383 and a 2N3055 and 2N2955 but never got around to trying it.
National semiconductor has documented this type of amp using a LM377 and a pair of complimentary transistors in the 15 to 20 watt range back in the late 70's and early 80's.
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Hehe think i was a little tired when i wrote that post, thanks for the correction.
Now the numbers with an input of 55V +/- on the TDA7293 (again using some simple voltage regulator input can be just under 60V, my TDA7294 is actually running 50V!!! and has been for 3+ years)
With 55V you can achieve:
---------- Normal --- Bridged
8 Ohm = 189W -- 756W
4 Ohm = 378W -- 1512W
2 Ohm = 756W -- 3024W
1 Ohm = 1512W -- 6048W
NOTE: If you use 1x Pair of transistors you will be limited to about 600W, so just to be "safe" go by the "formula" of 500W pr transistor pair, so if you want > 500W in 2 Ohm use 2x Pair Transistors, Now for Bridged power of 1000W 4Ohm you can just use 1x Pair Transistors pr AMP
Now the numbers with an input of 55V +/- on the TDA7293 (again using some simple voltage regulator input can be just under 60V, my TDA7294 is actually running 50V!!! and has been for 3+ years)
With 55V you can achieve:
---------- Normal --- Bridged
8 Ohm = 189W -- 756W
4 Ohm = 378W -- 1512W
2 Ohm = 756W -- 3024W
1 Ohm = 1512W -- 6048W
NOTE: If you use 1x Pair of transistors you will be limited to about 600W, so just to be "safe" go by the "formula" of 500W pr transistor pair, so if you want > 500W in 2 Ohm use 2x Pair Transistors, Now for Bridged power of 1000W 4Ohm you can just use 1x Pair Transistors pr AMP
Yes, Very Good!
I couldn't remember off hand which chip was the higher voltage one ,TDA7293. he,he
Most would probably not push them that hard, But, I know me !!!
2.7 amps over spec is not that bad especially for occasional peaks.
But, I personally would feel more safe with the added outputs.
I am currently running my DC300a on a 1.6 ohm load and it gets quite hot at times even though its heatsink leaves much to be desired!
Keep up the Great Work and Keep on DIYin' !!!!
jer
I couldn't remember off hand which chip was the higher voltage one ,TDA7293. he,he
Most would probably not push them that hard, But, I know me !!!
2.7 amps over spec is not that bad especially for occasional peaks.
But, I personally would feel more safe with the added outputs.
I am currently running my DC300a on a 1.6 ohm load and it gets quite hot at times even though its heatsink leaves much to be desired!
Keep up the Great Work and Keep on DIYin' !!!!
jer