TDA8954TH 24V 2X420W


2015-07-08 5:23 pm
Hello everybody .

I need some advice again :) ok so I have this amplifier and I built a quick mock up to test this amplifier .

my ac transformer is a 24-0-24 the amp runs ok but it hum too much for my liking . dc offset on each channel is 0,35

what I did do was connect the + terminal to the right channel and the negative to the left channel output on the amplifier and ran it to one speaker ( mono mode ) The sound improved so so much my reaction was wow and the noise floor dropped so much .

The output of the amplifier decreased as well as in volume is this because how I have wired on speaker up has that changed the ohms from 8 - 4 ohm

also how I see it - when bridging the 2 channels together is that using all the smoothing caps for one channel ( hence less noice or ripple )

this is the amplifier in question
Tihebeyan TDA8954TH Audio Amplifier Board, 24V 2x420W: Electronics
Please pull the mains plug, fast.
Offset is too high. Maybe you screwed up on the transformer leads.

I do not see how you could run this amp bridged without an additional symmetric driver stage. Bridged amps get more loud, not less.

You just connected something intentionally totally wrong.
You do not experiment with amps. All you can do this way is blow them.

Hum is produced if you connect ground lines the wrong way. Not the amps, but your fault. These are parts, not finished amps and you need some basic knowledge to build something working from them.

You do not change anything with the smoothing caps that reduces hum. This is a "+34V 0V -34V" power supply, bridged or single ended.

Maybe post some good pictures of your construction, showing all details, so we can tell you what you got wrong.


2015-07-08 5:23 pm
The dc offset is 0.35 mv
This amplifier is already running in a bridged amplifier design

Also I have a bulb dimmer attached . What I was asking is how come the single is so much cleaner and sounds so much more when I connect one 8ohm speaker across both channels