D1047 amplifier

[S-fr]

I'm using d1047 based amplifier board for my sub, its actually a 2.1 amplifier board, where 2 of the 2050s are for left and right and d1047s for the sub, the thing is on high volume my stereo speakers are working find but the sub gets buzz like sound ig, the audio receiver is fine as well the audio in put as the stereo speaker output is clear there is no buzz of anything like that when the volume is full, so on the subwoofer section what could be at fault also

 

[ZipZapOuch]

Your sub may be...
1) vibrating internally due to the high base volume (heavy components like large capacitors, inductors or mounting hardware (even wires or cord restraints) can be vibrating. Hot glue seems to work well without causing problems with the components. Also, check your speakers. A strong bass amplifier can cause screws to pull out of a particle board cabinet and allow the speaker to vibrate.

2) bass frequencies take a lot (A LOT) of power. Your power supply may not be up to the task for the volumes you are trying to use. A weak power supply may output lower and lower voltage as your bass amplifier draws more amperes. At some point the amplifier is trying amplify and output a voltage that is greater than the input. This causes an output wave to be "clipped" and sound buzzy.

If you have a 3amp 12v supply, for example, you could try a 10amp, 12v supply. Or some other higher amperage power supply at whatever your operating voltage may be.

There are other causes, mechanical vibrations and signal clipping but let's start with those.

Others may be oscillating amplifier, ground loops and other electrical interference or resonances from your crossover (for example).

 

[Tony Stewart]

Most likely your AC rectifier and capacitors are undersized and you are getting excessive 100 Hz ripple on 50 Hz. I suggest a >10A diode bridge on a heatsink and 20k to 100k uF's. 2200 uF is not enough.

Measure your DC ripple.

 

[audioguru]

A loudspeaker makes a buzz sound when its amplifier is clipping or when the voice coil is hitting the magnet structure.
Both problems are eliminated when you turn down the loudness (overloading).

 

[ZipZapOuch]

The power supply capacitors may be too small. For low frequency tones at high power, you can drain the charge and lose any (all) filtering of the rectified AC and that ripple will come through in the audio at high volumes.

 

[audioguru]

The Sammar amplifier is (was?) a kit from Pakistan. The sales sheet wrongly says it is a stereo amplifier with a frequency response to only 2000Hz. Clicking on its photo, the photo changes into a different circuit board maybe a sub-woofer mono amplifier kit. The amplifier is powered from two transformers, maybe the sub-woofer amplifier is powered from a transformer that is too weak or the two transformers were wrongly swapped.

A You Tube video (narrated in the Pakistan language?) plays 2.1 loud music with no buzzing from the sub-woofer.

 

[S-fr]

A loudspeaker makes a buzz sound when its amplifier is clipping or when the voice coil is hitting the magnet structure.
Both problems are eliminated when you turn down the loudness (overloading).

Well i had this sub for quite some time so i know how low qnd far it can go, so the issue is with the amplifier

 

[S-fr]

Your sub may be...
1) vibrating internally due to the high base volume (heavy components like large capacitors, inductors or mounting hardware (even wires or cord restraints) can be vibrating. Hot glue seems to work well without causing problems with the components. Also, check your speakers. A strong bass amplifier can cause screws to pull out of a particle board cabinet and allow the speaker to vibrate.

2) bass frequencies take a lot (A LOT) of power. Your power supply may not be up to the task for the volumes you are trying to use. A weak power supply may output lower and lower voltage as your bass amplifier draws more amperes. At some point the amplifier is trying amplify and output a voltage that is greater than the input. This causes an output wave to be "clipped" and sound buzzy.

If you have a 3amp 12v supply, for example, you could try a 10amp, 12v supply. Or some other higher amperage power supply at whatever your operating voltage may be.

There are other causes, mechanical vibrations and signal clipping but let's start with those.

Others may be oscillating amplifier, ground loops and other electrical interference or resonances from your crossover (for example).

Ook so 1st one isn't the cause, ill try looking into the 2nd one

 

[S-fr]

The Sammar amplifier is (was?) a kit from Pakistan. The sales sheet wrongly says it is a stereo amplifier with a frequency response to only 2000Hz. Clicking on its photo, the photo changes into a different circuit board maybe a sub-woofer mono amplifier kit. The amplifier is powered from two transformers, maybe the sub-woofer amplifier is powered from a transformer that is too weak or the two transformers were wrongly swapped.

A You Tube video (narrated in the Pakistan language?) plays 2.1 loud music with no buzzing from the sub-woofer.

Nah, it is a 2.1, two 2050s are for the stereo and d1047s for the subwoofer, also i dont believe much in the product datasheet much when they dont bother looking much into the actual ic data sheet, and it is powered by one transformer ie 25-0-25 and 12-0-12 so it seems that its either that the transformer is weak or the capacitor aren't the right one, but does the capacitor matter matter that much?

 

[S-fr]

The power supply capacitors may be too small. For low frequency tones at high power, you can drain the charge and lose any (all) filtering of the rectified AC and that ripple will come through in the audio at high volumes.

Ok so rn there are two capacitor that are 2200uf, should i upgrade em? I guess i got some 50v 6800uf cap, will it be fine if i swap em?? Also can you look into the capacitors positioning they aren't in parallel, im not well knowledged in these kinda things

 

[audioguru]

The You Tube video and the amplifier screw terminals show two transformers. Do you have only one transformer?

 

[S-fr]

The You Tube video and the amplifier screw terminals show two transformers. Do you have only one transformer?

Yeah I got one

 

[audioguru]

The transformer voltages are rectified and filtered into +/-33V and +/-15V.
The +/-33V can power the subwoofer amplifier producing 62W into 8 ohm at low distortion.
The +/-15V can power the TDA2030 stereo amplifiers producing 10W per channel into 8 ohms with low distortion.

The total audio power is 82W plus the heating of the class-AB amplifiers is about 70W but the transformer appears to be too small for a total power of 152W.
The two 2200uF capacitors are +/-14V filters for the 10W per channel stereo amplifier, 2200uF capacitors are fine.
Two larger capacitors are missing to filter the 62W sub-woofer amplifier.

1) Did you measure the transformer voltages then connect the 25V+25V wires to the subwoofer amplifier?
2) Are the speakers 8 ohms?

 

[S-fr]

The transformer voltages are rectified and filtered into +/-33V and +/-15V.
The +/-33V can power the subwoofer amplifier producing 62W into 8 ohm at low distortion.
The +/-15V can power the TDA2030 stereo amplifiers producing 10W per channel into 8 ohms with low distortion.

The total audio power is 82W plus the heating of the class-AB amplifiers is about 70W but the transformer appears to be too small for a total power of 152W.
The two 2200uF capacitors are +/-14V filters for the 10W per channel stereo amplifier, 2200uF capacitors are fine.
Two larger capacitors are missing to filter the 62W sub-woofer amplifier.

1) Did you measure the transformer voltages then connect the 25V+25V wires to the subwoofer amplifier?
2) Are the speakers 8 ohms?

Yep i checked the transformer first before the connection and connected the wires according
Both the stereo speaker are around 8 ohms and sub is 6 ohms
Also the capacitors for ±25v and ±12v 2200uf capacitor are used, should i swap the capacitor for ±25v with bigger capacitor?

 

[S-fr]

Your sub may be...
1) vibrating internally due to the high base volume (heavy components like large capacitors, inductors or mounting hardware (even wires or cord restraints) can be vibrating. Hot glue seems to work well without causing problems with the components. Also, check your speakers. A strong bass amplifier can cause screws to pull out of a particle board cabinet and allow the speaker to vibrate.

2) bass frequencies take a lot (A LOT) of power. Your power supply may not be up to the task for the volumes you are trying to use. A weak power supply may output lower and lower voltage as your bass amplifier draws more amperes. At some point the amplifier is trying amplify and output a voltage that is greater than the input. This causes an output wave to be "clipped" and sound buzzy.

If you have a 3amp 12v supply, for example, you could try a 10amp, 12v supply. Or some other higher amperage power supply at whatever your operating voltage may be.

There are other causes, mechanical vibrations and signal clipping but let's start with those.

Others may be oscillating amplifier, ground loops and other electrical interference or resonances from your crossover (for example).

Nah i ch checked, its non of these and i notice one more thing, that when i touch the frame or the wire terminal connector either on the sub or on the amplifier board that clipping starts real quick, i would like to know which format is best for the video so that i can upload it so you guys can see the real issue and the sound is more like gun shot like "thhatt" then the zzzz

 

[ZipZapOuch]

Yep i checked the transformer first before the connection and connected the wires according
Both the stereo speaker are around 8 ohms and sub is 6 ohms
Also the capacitors for ±25v and ±12v 2200uf capacitor are used, should i swap the capacitor for ±25v with bigger capacitor?

I'd definitely use 10,000uF if you're seeing clipping and you think your power supply is stiff enough in all other regards.