Why does Denafrips have this warning? And how do you connect a subwoofer? "Please do not connect the amplifier' speaker output to the sub-woofer high-

[shion_ca]

Please do not connect the amplifier' speaker output to the sub-woofer high-level input.

So why can't you wire in parallel a highlevel input into a sub... shouldn't cause an impedence drop or anything. What's the issue... and how do you wire the subwoofer then?

 

[Keith_W]

The issue relates to how some subwoofers handle high level balanced output and amplifier topology.

Some subwoofers have: +ve input goes into the sub amp, and -ve goes to the ground.

However, push-pull amps (i.e. all Class AB amplifiers) have: +ve output = push, -ve output = pull. If you connect the negative amplifier terminal to the subwoofer terminal, you will send the "pull" signal to the ground. This is obviously bad and can damage your amp.

For this reason, high level inputs in subwoofers should never be used.

 

[shion_ca]

Is there a way to tell with a multimeter if my sub has made this error?

 

[LTig]

The issue relates to how some subwoofers handle high level balanced output and amplifier topology.

Some subwoofers have: +ve input goes into the sub amp, and -ve goes to the ground.

However, push-pull amps (i.e. all Class AB amplifiers) have: +ve output = push, -ve output = pull

You mean bridged amplifiers, these are amplifiers which use two internal amplifier stages of any class type to work as one. One stage is fed with the direct input signal, the other one with inverted input signal. The speaker is then connected to the '+' outputs of both stages.

If you connect the negative amplifier terminal to the subwoofer terminal, you will send the "pull" signal to the ground. This is obviously bad and can damage your amp.

For this reason, high level inputs in subwoofers should never be used.

Yep. Both '-' inputs of the sub are at ground level and would shortcut the '-' outputs of both amplifier stages.

 

[Prana Ferox]

I would expect a high-level input at the sub end to just go to the primary side of a transformer. Why would it be grounded at the sub?