Thanks, that's what I read too but I was still hoping there's a way. Would it be possible to just use a dummy load on the other channel? I have no idea what value and kind of resistor I'd need though.
Just short the unput to GND for that channel. At the otput you may put 100ohm/0.5W resistor, to keep the output with low potential.
Awesome, thanks. I'll finally be able to post listening impressions for this amp once I get the right transformer for it.
I need help wiring this board.
The power and audio input terminals have a ground with which I don't know what to do. I got a toroidal transformer with dual 24V ac outs while this board requires 24V as well. I've read about how the dual outs can be wired in series and connecting one end of the connections to the ground but this would add the voltage to 48V. Should I get a 12V dual out transformer and wire it in series instead?
Also, what do I do with the ground terminal on the audio input if I want to connect L and R rca connectors?
The power and audio input terminals have a ground with which I don't know what to do. I got a toroidal transformer with dual 24V ac outs while this board requires 24V as well. I've read about how the dual outs can be wired in series and connecting one end of the connections to the ground but this would add the voltage to 48V. Should I get a 12V dual out transformer and wire it in series instead?
Also, what do I do with the ground terminal on the audio input if I want to connect L and R rca connectors?
All is described in this picture: https://luckyretail.com/Uploadfile/201806062/159570/159570-7.jpg
If your transformer has separate secondaries, then see this picture: http://sound.whsites.net/xfmr8-1.gif
You need the right part - 0V connect to the GND.
The inputs connect to the signal source, preferably with 10k A-type logarithmic potentiometer.
If your transformer has separate secondaries, then see this picture: http://sound.whsites.net/xfmr8-1.gif
You need the right part - 0V connect to the GND.
The inputs connect to the signal source, preferably with 10k A-type logarithmic potentiometer.
Thanks for the reply. The 2nd picture is exactly what I was describing but I would need dual 12V outs in series to not go over the max voltage of this board. I don't know why the first picture recommends dual 24V outs when you have to wire in series to connect to the ground which would add the voltage to 48V 😕
I purchased the wrong transformer for it but I guess I can use this on an IRS2092S with rectifier board for a subwoofer project.
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Ah, I see now thanks. No more problem with the power supply but I still can't make the audio input work. How do I wire it to a pair of rca connectors without a potentiometer? How do I deal with the ground pin? I already have a passive preamplifier that I will use so I don't need a potentiometer.
Yes, that's what i'm trying to do 🙂
The preamp is something like this:
Amazon.com: Nobsound High Precision Passive Preamp Volume Controller VOL Control HiFi Preamplifier ALPS (RCA&HiFi Version, Black): Home Audio & Theater
I want to be able to connect the audio input of the amplifier board to the rca out of this kind of passive preamp but I don't know what to do with the ground..
EDIT: It should probably be advertised as a 'passive volume controller' since it doesn't really amplify the signal.
The preamp is something like this:
Amazon.com: Nobsound High Precision Passive Preamp Volume Controller VOL Control HiFi Preamplifier ALPS (RCA&HiFi Version, Black): Home Audio & Theater
I want to be able to connect the audio input of the amplifier board to the rca out of this kind of passive preamp but I don't know what to do with the ground..
EDIT: It should probably be advertised as a 'passive volume controller' since it doesn't really amplify the signal.
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Great, thanks for that! I will try this later when I can and report back on the results. Cheers.
I finally got around to hooking the amp up and everything worked well 🙂
I can't really use it with my main speakers running on active crossovers yet (Fountek NeoCD3.5H + Vifa NE180W) but I tested it on my pair of Usher S-520s and they sounded good! Full and impactful, in contrast to how these speakers have a tendency to sound bright and thin with some hardness in the upper midrange with some equipment. I did not get this sound with this amp at all.
There is a slight hum on both channels that is audible when you put your ear really close to the drivers, but inaudible even less than a meter away. The heatsink gets rather warm in 24V operation but even a very slight breeze from a distant fan is adequate to keep it manageable.
Other than these, everything's good. I look forward to getting this setup fitted in a proper case.
I can't really use it with my main speakers running on active crossovers yet (Fountek NeoCD3.5H + Vifa NE180W) but I tested it on my pair of Usher S-520s and they sounded good! Full and impactful, in contrast to how these speakers have a tendency to sound bright and thin with some hardness in the upper midrange with some equipment. I did not get this sound with this amp at all.
There is a slight hum on both channels that is audible when you put your ear really close to the drivers, but inaudible even less than a meter away. The heatsink gets rather warm in 24V operation but even a very slight breeze from a distant fan is adequate to keep it manageable.
Other than these, everything's good. I look forward to getting this setup fitted in a proper case.
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What do you guys think of this one?
New 420W *2 Large Power TDA8954TH AD Digital Audio Amplifier Board Dual AC 24V | eBay
$36 built and shipped just needs a 28vac 400VA trafo and can do 200w into 4ohms. Sounds unreal - but maybe someone here has really pushed these to the 200w limit?
New 420W *2 Large Power TDA8954TH AD Digital Audio Amplifier Board Dual AC 24V | eBay
$36 built and shipped just needs a 28vac 400VA trafo and can do 200w into 4ohms. Sounds unreal - but maybe someone here has really pushed these to the 200w limit?
There is a switch mode DC-DC convertor for the fans - it may introduce noise in the sound...
Also the noise of the fans...
The only one positive thing is that the output inductors are actively cooled by the air from the fans.
Also the noise of the fans...
The only one positive thing is that the output inductors are actively cooled by the air from the fans.
Just tested this amp. No switch noise from fan. No hum or hiss. Using with 25V 250VA Avel Lindbergh trafo. Using 10R and double diode GLB between earth GND and center tap GND. Tested on 90dB speakers and could barely hear any noise or hum with ears pressed to speaker come.
Fan noise is loud. Could add a power resistor or string of diodes to drop speed. Does not need to be this fast.
Tested on 82dB multi-way speakers and definitely a lot of power for bass kick drums.
Fluke 101 measured 200uV rms noise at output. About 50mV DC offset.
Fan noise is loud. Could add a power resistor or string of diodes to drop speed. Does not need to be this fast.
Tested on 82dB multi-way speakers and definitely a lot of power for bass kick drums.
Fluke 101 measured 200uV rms noise at output. About 50mV DC offset.
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Doing a little more listening on my 10F/RS225 FAST monitors (82.4dB sensitivity, 100w max) and I like what I hear. Very powerful amp with superb headroom. When preamp is turned up, I hear a little hum from the mains - it might be that the built in PSU can use some larger smoothing caps. If a CRC were used, might even be better. Right now just a pair of 4700uF caps after the bridge per rail. The sound is very nice and spatiality is quite good. Sounds a lot like a decent Class AB.
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Today I saw that there is new PCB version on AliExpress: Latest models TDA8954 Class D 2.0 channel 210W+210W high power digital amplifier board-in Amplifier from Consumer Electronics on AliExpress - 11.11_Double 11_Singles' Day
I like the placement of the components on the board and the presence of speakers protection with C1237 chip.
So, I purchased one board to test it 🙂
I like the placement of the components on the board and the presence of speakers protection with C1237 chip.
So, I purchased one board to test it 🙂