I was looking at the datasheet of TDA2050. I saw two schematics- one with the split supply and the other with a single supply.
I want to use an existing 12 V SMPS to power up the chip in lieu of a transformer.
My question is, will there be any difference/deterioration in the sound quality if I use the single supply?
Thank you.
I want to use an existing 12 V SMPS to power up the chip in lieu of a transformer.
My question is, will there be any difference/deterioration in the sound quality if I use the single supply?
Thank you.
12V.. output capacitor... This will not sound good.
1000uF is too small, it may sound funny but normal to many people...
I would hack the 12V to dual 12V
No ouput capacitor means your amp has clear and smooth response to lowest possible fq
If you have 1000uF electrolytic cap on the output then more likely at 40 and below it will sound muddy and poor..
1000uF is too small, it may sound funny but normal to many people...
I would hack the 12V to dual 12V
No ouput capacitor means your amp has clear and smooth response to lowest possible fq
If you have 1000uF electrolytic cap on the output then more likely at 40 and below it will sound muddy and poor..
Oh thank you so much Mikhus.
I have two 12 Volt SMPS. But unfortunately one is showing 12.78V and another 12.95. So Not perfectly symmetrical. Will that distort the sound or cause DC offset at the output?
Or do you suggest me to obtain a 24V SMPS and then split it with a bridge rectifier and electrolytic caps (if that is possible at all ) ?
Kindly guide me to hack the 12v one to a dual 12v.
I have two 12 Volt SMPS. But unfortunately one is showing 12.78V and another 12.95. So Not perfectly symmetrical. Will that distort the sound or cause DC offset at the output?
Or do you suggest me to obtain a 24V SMPS and then split it with a bridge rectifier and electrolytic caps (if that is possible at all ) ?
Kindly guide me to hack the 12v one to a dual 12v.
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4700 uF will make your response -3 dB at 4.23 Hz. That should be fine.
The downside of an output coupling capacitor may be more theoretical than actual. As an electrolytic cap gets signal voltage across it, it will generate a little distortion. More voltage across the cap, more distortion.
Thus, if the cap is big enough, for all practical purposes, very little signal voltage develops across it, and there is not enough distortion to make a difference.
Doug Self talks about the effect in his Audio Power Amplifier design books in the case of the DC block in the feedback network. That's why he makes that cap much bigger than you'd normally choose.
Akitika GT-101 Audio Power Amplifier Kit
The downside of an output coupling capacitor may be more theoretical than actual. As an electrolytic cap gets signal voltage across it, it will generate a little distortion. More voltage across the cap, more distortion.
Thus, if the cap is big enough, for all practical purposes, very little signal voltage develops across it, and there is not enough distortion to make a difference.
Doug Self talks about the effect in his Audio Power Amplifier design books in the case of the DC block in the feedback network. That's why he makes that cap much bigger than you'd normally choose.
Akitika GT-101 Audio Power Amplifier Kit
Disagree on the part "worse sound quality with single supply because of the output capacitor".
In every amplifier the speaker is directly coupled to some kind of "output capacitor". Even in a split PSU. Think how the signal goes, and especially where it ends after the loudspeaker...
In single supply, use a cap-bank at the output instead of a single output capacitor.
Special attention also to the selection of the input capacitors - as always...
The only difference will be, instead of 2 cap banks, with a single supply you will only have one - which is nice... ;-)
In every amplifier the speaker is directly coupled to some kind of "output capacitor". Even in a split PSU. Think how the signal goes, and especially where it ends after the loudspeaker...
In single supply, use a cap-bank at the output instead of a single output capacitor.
Special attention also to the selection of the input capacitors - as always...
The only difference will be, instead of 2 cap banks, with a single supply you will only have one - which is nice... ;-)
So how can a DC coupled amp maintain a perfect LF squarewave response (right down to DC as a valid output signal) if the load couples through the PSU caps ?
A capacitor does not allow to pass a DC current.
A split supply amp allows to pass a DC current to the load which can be destructive, so it is often provided with a protective relay.
This demonstrates that in amps with split power supply, the speaker is not directly coupled to some kind of output capacitor.
A capacitive coupled output has the great advantage to protect the load from DC in the mot simple manner. The electrolytic cap introduces some non-linearity but this can be circumvented by including it in the feedback.
The design of such an amp can then be very simple and show performances equal to the best :
MJR7-Mk5 Mosfet Power Amplifier Design Notes
Disagree...
All wire resistance (everywhere) takes care of the fact that the first thing the speaker is connected to is the capacitors, always. Because those are the last thing after the PSU, always.
Haven't ever asked why so many amps have an output DC protecting circuit and why the power supply caps combined with the load do not form a high-pass filter ?
Your view belongs to some recurrent errors seen since forty years.
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Just to be more precise :
A power supply made with transformer, rectifier and reservoir capacitors has imperfections like ripple and not null ouput impedance. But fundamentally, it behaves as a DC source.
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