Topping PA5 (TPA325X) : Is a modification worth it? ?

D

Deleted member 148505

Disclosing the IC that was used will reduce the perceived value of the amp since you can get the IC for cheap, then the build quality and the parts that were used will have a difficulty justifying its price.

Replacing the chip will work since it is pin by pin compatible. (Unless there is some form of elaborate IP protection technique that will melt if the IC section was soldered LOL) Also, TPA3251 and TPA3255 have different gains so if you put the wrong chip you won't get the same performance (or might not be stable at all because of PFFB configuration).

Heating plate is just around 4USD. With a variac, you can easily control the temp and desolder the IC without damaging it.
The original IC can be put back if anything goes wrong.

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Agree ) :)

The TPA325X has enormous potential! moreover the next Allo TPA3255 announces these measures: (I have already shared them)


THD+N 5W , 1Khz 0.00014
THD+N 100W 20-20Khz 0.0097
THD+N 10W 20-20Khz 0.0091
Hi,
So, to summarise this thread, the Topping uses a TPA3251 IC, and has performance as per post #5 where it shows that higher frequencies have significant increased THD.

The Allo you refer to uses the TPA3255 and has a low THD compared to the Topping, yet we don't know how it achieves the low THD at higher frequencies.

If neither the Topping nor the Allo have the circuit diagram provided, then how can anyone copy, or take inspiration for a feedback network that can improve the TPA implementation to attain a similar performance as per the Purifi modules etc ?

I am building 6x the Elektor Class D amplifiers for a self build active 3 way speaker, since they are cheap. So i agree that purchasing the Purifi modules can be expensive.

Regards,
Shadders.
 
Hi,
So, to summarise this thread, the Topping uses a TPA3251 IC, and has performance as per post #5 where it shows that higher frequencies have significant increased THD.

The Allo you refer to uses the TPA3255 and has a low THD compared to the Topping, yet we don't know how it achieves the low THD at higher frequencies.

If neither the Topping nor the Allo have the circuit diagram provided, then how can anyone copy, or take inspiration for a feedback network that can improve the TPA implementation to attain a similar performance as per the Purifi modules etc ?

I am building 6x the Elektor Class D amplifiers for a self build active 3 way speaker, since they are cheap. So i agree that purchasing the Purifi modules can be expensive.

Regards,
Shadders.
Hi,
To add correction, the Topping PA5 uses the TI TAS5613A IC.

Regards,
Shadders.