Hi !
I wrote somewhere that negative outlet resistance of Amp. It will decrease the interinflexion distortshans on the loudspeqaker.Is It truly ..?!!
I tried make TDA-7294 to works as a source electricity ,òhe sound become cleaner but ther is wheeze .
What is wrong,how òî improve it ?
Let me know if you alredy did it or where cane I get a help .
I wrote somewhere that negative outlet resistance of Amp. It will decrease the interinflexion distortshans on the loudspeqaker.Is It truly ..?!!
I tried make TDA-7294 to works as a source electricity ,òhe sound become cleaner but ther is wheeze .
What is wrong,how òî improve it ?
Let me know if you alredy did it or where cane I get a help .
I am usually not understanding "negative resistans". 😕
To me that say a material conducts current
MORE than a SHORT-CUT.
Must be some better way to describe the thing.
TDA7293 is almost the same IC.
He is working now with some TDA7293
This Thread:
Qs about a two-channel quad paralleled TDA7293 amp...
Discuss with him.
Wheeze could come from Input or from Feedback.
Or from Power-Supplies or from Grounding.
To me that say a material conducts current
MORE than a SHORT-CUT.
Must be some better way to describe the thing.
TDA7293 is almost the same IC.
He is working now with some TDA7293
This Thread:
Qs about a two-channel quad paralleled TDA7293 amp...
Discuss with him.
Wheeze could come from Input or from Feedback.
Or from Power-Supplies or from Grounding.
I'm sorry!
Sorry for my bad English 🙂 I 'll try to describe what I mean to sey:
I am trying to join the loudspeaker in feedback (negative feedback by voltage ) so loudspeaker drives the Amp.If loudspeaker's magneto resist rise Amp. also rise.
Sorry for my bad English 🙂 I 'll try to describe what I mean to sey:
I am trying to join the loudspeaker in feedback (negative feedback by voltage ) so loudspeaker drives the Amp.If loudspeaker's magneto resist rise Amp. also rise.
Interesting Amplifier Technique
So the Current going into Speaker is Proportional to the input Voltage
The speaker is instead of feedback-resistor.
TDA7294 is not made for this. Not many amplifiers in the world are!
It could work, but it would be better
to make a special Amplifier
that is made for it.
Your thinking is right! (we think same) 😉 😉
I have only read ONE design in 20 years, with this technique.
It is a low power amplifier.
The Current Sensing Resistor has to be low in value
and not inductive
and you can use a buffer to change the impedance.
So the Current going into Speaker is Proportional to the input Voltage
The speaker is instead of feedback-resistor.
TDA7294 is not made for this. Not many amplifiers in the world are!
It could work, but it would be better
to make a special Amplifier
that is made for it.
Your thinking is right! (we think same) 😉 😉
I have only read ONE design in 20 years, with this technique.
It is a low power amplifier.
The Current Sensing Resistor has to be low in value
and not inductive
and you can use a buffer to change the impedance.
You guys seem to mix two different things. There are amplifiers with a negative output resistance and there are transconductance amplifiers.
Amps with a negative output resistance have a specially arranged feedback so that if you measured the impedance conventionally you end up with a negative number. The idea is to cancel the DC resistance of the voice coil and wires. Take a look here http://sound.westhost.com/project56.htm
Transconductance amps deliver a current that is proportional to the input voltage, they have a (almost) infinite output impedance. There is a thread about them on the analog forum. THE reference work on this was done by M. Hawksford. http://www.essex.ac.uk/ese/research/audio_lab/malcolms_publications.html It can be found in the JAES. There has been a smaller amp described in EW&WW. The first is 75W, the second 10W.
Both types are intended to drive the speaker direcly, no crossover! Hope this clears a bit.
Amps with a negative output resistance have a specially arranged feedback so that if you measured the impedance conventionally you end up with a negative number. The idea is to cancel the DC resistance of the voice coil and wires. Take a look here http://sound.westhost.com/project56.htm
Transconductance amps deliver a current that is proportional to the input voltage, they have a (almost) infinite output impedance. There is a thread about them on the analog forum. THE reference work on this was done by M. Hawksford. http://www.essex.ac.uk/ese/research/audio_lab/malcolms_publications.html It can be found in the JAES. There has been a smaller amp described in EW&WW. The first is 75W, the second 10W.
Both types are intended to drive the speaker direcly, no crossover! Hope this clears a bit.
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