Hi,
Following setup:
- I have a balanced signal from the source (DI-Box)
- I would like to go into a hifi amp, with '+'-signal on right and '-'-signal on left.
- now I would expect the reverse audio signal on the both amp-outputs.
- feed a 8Ohm speaker with right channel 'hot' and left channel 'hot'
Would this work?
Should I connect the ground-output posts?
Thanx
Stephan
Following setup:
- I have a balanced signal from the source (DI-Box)
- I would like to go into a hifi amp, with '+'-signal on right and '-'-signal on left.
- now I would expect the reverse audio signal on the both amp-outputs.
- feed a 8Ohm speaker with right channel 'hot' and left channel 'hot'
Would this work?
Should I connect the ground-output posts?
Thanx
Stephan
One issue that you encounter with the idea you propose is the due to the behavior of the amp channels with respect to the speaker and each other, the impedance of the speaker will appear to be half what it is specified as on the speaker. In other words, the amp would think that an 8 ohm speaker is a 4 ohm speaker, etc. This is ok if the speaker impedance is high enough, and the amp is built well. However, if the amp doesn't have a lot of extra current capability on the output, and/or the speaker impedance is below 8 ohms, then you may destroy the output of the amp, and maybe more.
Peace,
Dave
Peace,
Dave
That is one reason for bridging, that I would be able to get more power into the 8Ohm speaker
It should work,providing that the amps have identical gain.
And if the driving signals have an Identical voltage level.
No you do not need the ground posts.
Jer
By the way, what will happen, if the voltage level of the two channels differs by a higher margin?
It should also work if you connect the + output from the source to BOTH the + inputs of RIGHT and LEFT, then connect the - output from the source to the signal ground on BOTH the RIGHT and LEFT inputs.
In this configuration, your speaker would be connected to + on the right and - on the left.
Same result either way.
In this configuration, your speaker would be connected to + on the right and - on the left.
Same result either way.
No that will not work !
The Inputs to the amps must be out of phase what you just described, The phase of the input signals will be the same and then you will get 0V difference between the two outputs regardless of what the input signal level is.
Also if the signals are not of equal value then you will have one channel fighting the other and the uneven cancellations will result in higher distortions.
Anyway I am glad to hear that you got it working !!!
Cheers !!
jer
The phase of the OUTPUT signals will be 180 degrees out of phase... that is why I said to connect your speaker + to the LEFT and speaker - to the RIGHT. The + outputs of the amp will be IN PHASE, but the opposite outputs will be OUT OF PHASE.
If it won't work, then my amplifier must exist in a parallel universe where everything works opposite of how it works in our universe.
"The + outputs of the amp will be IN PHASE".
No this will not work !
That will work as a paralleled amp operation, But, not a Bridge Tied load configuration ( hence BTL or Bridged).
The outputs of the amp must be out of phase with each other.
In order to make this work.
1# the source ground goes to the amp inputs ground.
2# the source + connected to the right amp input.
3# the source - connected to the left amp input.
4# the speaker + connected to the right amp + output.
5# the speaker - connected to the left amp + output.
This way the amp signals will be out of phase as they need to be in order for it to work, and, the speaker will be in phase with the source signal.
Both amps - output (or ground) are not connected to any thing at all.
jer
No this will not work !
That will work as a paralleled amp operation, But, not a Bridge Tied load configuration ( hence BTL or Bridged).
The outputs of the amp must be out of phase with each other.
In order to make this work.
1# the source ground goes to the amp inputs ground.
2# the source + connected to the right amp input.
3# the source - connected to the left amp input.
4# the speaker + connected to the right amp + output.
5# the speaker - connected to the left amp + output.
This way the amp signals will be out of phase as they need to be in order for it to work, and, the speaker will be in phase with the source signal.
Both amps - output (or ground) are not connected to any thing at all.
jer
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Jer,
You seem to be missing what I'm saying. You are correct that you cannot do it the way I explained IF you use the POSITIVE OUTPUTS on both the left and right channel of the amplifier. If, however, you wire the inputs the way I explained and use the POSITIVE OUTPUT on one channel AND THE NEGATIVE OUTPUT on the other channel, it will work just fine, I promise.
You seem to be missing what I'm saying. You are correct that you cannot do it the way I explained IF you use the POSITIVE OUTPUTS on both the left and right channel of the amplifier. If, however, you wire the inputs the way I explained and use the POSITIVE OUTPUT on one channel AND THE NEGATIVE OUTPUT on the other channel, it will work just fine, I promise.
Yes, you may have been confusing me in your explaination,
"the POSITIVE OUTPUT on one channel AND THE NEGATIVE OUTPUT on the other channel"
If you are referring to the source output then yes you are correct.
But this is were you had started to confuse me,
"The + outputs of the amp will be IN PHASE, but the opposite outputs will be OUT OF PHASE" and,
"connect the + output from the source to BOTH the + inputs of RIGHT and LEFT"
I also definitely read this one wrong as well,
" your speaker would be connected to + on the right and - on the left."
You must try to be exact when explaining such things as sometimes things can get quite confusing,I know I have been there before and I have had to spend many hours retyping an explanation before.
In my last explanation I had caught an error in #5 were I had used a (+) when it should have been a (-). he,he
Sorry for the confusion.
jer
"the POSITIVE OUTPUT on one channel AND THE NEGATIVE OUTPUT on the other channel"
If you are referring to the source output then yes you are correct.
But this is were you had started to confuse me,
"The + outputs of the amp will be IN PHASE, but the opposite outputs will be OUT OF PHASE" and,
"connect the + output from the source to BOTH the + inputs of RIGHT and LEFT"
I also definitely read this one wrong as well,
" your speaker would be connected to + on the right and - on the left."
You must try to be exact when explaining such things as sometimes things can get quite confusing,I know I have been there before and I have had to spend many hours retyping an explanation before.
In my last explanation I had caught an error in #5 were I had used a (+) when it should have been a (-). he,he
Sorry for the confusion.
jer
Here's what I was saying:
1) Connect the + output from the source to both amplifier + inputs.
2) Connect the - output from the source to both amplifier - inputs.
3) Connect the speaker + to the Left + output of the amplifier.
4) Connect the speaker - to the Right - output of the amplifier.
This will have the affect of summing the left and right amplifier power. It will do exactly the same thing as this:
1) Connect the + output from the source to the left amplifier + input.
2) Connect the - output from the source to the right amplifier + input.
3) Ground the - inputs of the amplifier.
4) Connect the speaker + to the Left + output of the amplifier.
5) Connect the speaker - to the Right + output of the amplifier.]
I've highlighted the main difference between the two approaches in red, bold text.
1) Connect the + output from the source to both amplifier + inputs.
2) Connect the - output from the source to both amplifier - inputs.
3) Connect the speaker + to the Left + output of the amplifier.
4) Connect the speaker - to the Right - output of the amplifier.
This will have the affect of summing the left and right amplifier power. It will do exactly the same thing as this:
1) Connect the + output from the source to the left amplifier + input.
2) Connect the - output from the source to the right amplifier + input.
3) Ground the - inputs of the amplifier.
4) Connect the speaker + to the Left + output of the amplifier.
5) Connect the speaker - to the Right + output of the amplifier.]
I've highlighted the main difference between the two approaches in red, bold text.
No,I don't think that you are understanding correctly.
The signals of the amplifiers must be out of phase to work in a bridged mode.
The - outputs of the amplifiers are tied to ground and bare no signal at all.
Unless it is an amplifier that is already configured in a BTL mode as in Car audio devices, in which if that were the case this would bare no advantage at all.
In a bridge configuration only the + outputs are connected to the load and are the only points that are active.
The - outputs of the amplifiers are just GROUND the same ground that is connected to the input side (source) of the amplifier,A simple continuity test can confirm this.
The only exception to this is when if the amplifier has a balanced input and is configured for unbalanced operation,where the - input (source) gets tied to ground as well.
Otherwise it would be just a matter of swapping the - and + input signals on one of the amplifier inputs (source output) in order to run them in a Bridged mode.
In a bridged mode configuration the output voltage will be twice the voltage of a what single amplifier can produce, With of course all things being equal.
Therefore supplying 4 times the power output providing that the amplifiers can produce the current that is demanded from them.
Or it will produce double the power of a single amplifier at an 8 ohm load into a 16 ohm load when configured as bridged .
jer
The signals of the amplifiers must be out of phase to work in a bridged mode.
The - outputs of the amplifiers are tied to ground and bare no signal at all.
Unless it is an amplifier that is already configured in a BTL mode as in Car audio devices, in which if that were the case this would bare no advantage at all.
In a bridge configuration only the + outputs are connected to the load and are the only points that are active.
The - outputs of the amplifiers are just GROUND the same ground that is connected to the input side (source) of the amplifier,A simple continuity test can confirm this.
The only exception to this is when if the amplifier has a balanced input and is configured for unbalanced operation,where the - input (source) gets tied to ground as well.
Otherwise it would be just a matter of swapping the - and + input signals on one of the amplifier inputs (source output) in order to run them in a Bridged mode.
In a bridged mode configuration the output voltage will be twice the voltage of a what single amplifier can produce, With of course all things being equal.
Therefore supplying 4 times the power output providing that the amplifiers can produce the current that is demanded from them.
Or it will produce double the power of a single amplifier at an 8 ohm load into a 16 ohm load when configured as bridged .
jer
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And there is where you are wrong. I haven't seen an automotive audio amplifier with the - speaker output tied to ground since the 80's.
The OP was asking about connecting his factory head unit to an aftermarket amplifier, no?
If the speaker outputs' - terminals are not grounded they are already BTL and there is no point in trying this.
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