Stereo to mono class-d amplifier

S

SentinelAeon

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Amp will be used for videogames, connected through 3.5mm to monitor. I am trying to convert stereo amp into mono but keep the volume knob. pins going in and out of the potenciometer are marked yellow, where i want to join L and R with resistor is marked red. So i am wondering, instead of putting separate resistor on each channel, could i just use 1 to bridge L and R channel (marked with red R) ? It wont be perfect mono, but for video games .., and i at least i protect the channels a bit and get to keep the potenciometer. The potenciometer when turned all the way has 1.2 ohm.

edit: Amp will be connected only through 3.5mm jack, so bluetooth wont be used. Would it be easier to just make mono using the pins around 3.5" ? Desolder the pins and put 50 or 100 ohms on each channel ?
 

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Not to get out of hand here,

1) i was asking about resistors for stereo -> mono because i cannot add the resistors if i want to keep the volume pot and i want to keep it. I could maybe desolder the pins near 3.5mm input but i think i will just risk it since its a 8$ amp.

2) question about volume is for a different usecase but same type of amp. I like to stick to high voltage, since they mentioned distortion i would bet my ass that lower voltage affects audio quality. And since on that particular amp i soldered my cable directly to 3.5mm pins, its really easy for me to add a resistor on each channel. Hopefuly that will reduce the volume without introducing to much hiss.

EDIT: I use this cheap amps all the time. I can't tell the difference between this 3116 amp and a big Pioneer amplifier i had before. Might be that the pioneer was that bad or im just deaf. In either case, since i started from complete 0, this amps are a great way to experiment and learn new things without being afraid to damage anything. If it was a 100$ amp, i wouldn't be so keen on testing whether resistors are needed when mixing stereo into mono
 
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You can just solder the resistors at the 3.5mm input cable.
 
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SentinelAeon said:
So far its working. Btw, i was wondering if it makes any difference in joining channels at 3.5mm channel or near the bluetooth receiver. Is it both relatively safe ?
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Both are safe - you may see slightly less noise from ambient interference by putting the resistors as close to the receiver as possible to minimize picking up noise by keeping the signal in the cable at slightly lower impedance. The noise difference would be so low that you should put the resistors where it is easiest to place them.
 
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It is safer with the resistors and all scenarios of possible damage or distortion are resolved with the resistors. It may be safe but we don't know all the operating scenarios - I would use them.
 
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At the same loudness, the cheap TPA3116 amplifier sounds the same as the powerful Pioneer amplifier because your hearing has an average normal loss at high frequencies (distortion) if you are a male who is older than 15 years old. At 35 years old the sounds are as muffled as an old AM radio or an old telephone (-3dB at 3kHz).
My hearing loss is normal for my age (79) and my hearing aids boost high frequencies A LOT.

The TPA3116 amplifier powered from 5VDC produces 1% clipping distortion at 2.5W into 4 ohms or 1.3W into 8 ohms.
Powered from a 12VDC supply, 1% distortion occurs at 15W into 4 ohms or 7.6W into 8 ohms.
 
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