TPA3255 - all about DIY, Discussion, Design etc

Founder of XSA-Labs
Joined 2012
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Never seen a 36-50V laptop supply . ;)

But yeah, the expanded voltage range is a nice bonus even when not going for full output power spec.

OT:

Except that, is your job 90% work at 10% money as well?

Chinese culture is, to my knowledge, let others do 90% of r&d and then take over the efforts for the rest of the 10% work. :)

But that's how the world is working today. Get everything for nothing.

I have been having great success using DC step up converters to get 35v from a 19v laptop SMPS.

In fact, two 19v SMPS and two DC step ups in series makes a +/-35v PSU for Class AB amps that is less expensive and far quieter than linear trafos.

These work really well. I have even used for Class A amp at 3amps continuous current at 34v.

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Does modulation occur in a linear PSU?

Of course, I said essentially that. I asked if there was anything showing up on the output of your amp from said modulation. Because we have this beautiful thing called psrr, the measure of how effective the amplifier is at ignoring power supply modulation.

That number is very large, as to essentially make your concern and ostensible solution useless.
 
Of course, I said essentially that. I asked if there was anything showing up on the output of your amp from said modulation. Because we have this beautiful thing called psrr, the measure of how effective the amplifier is at ignoring power supply modulation.

That number is very large, as to essentially make your concern and ostensible solution useless.

My concern is not to 'clean up' the power supply. The idea of a large cap bank is to provide current when needed by the Amp for bass.
 
It's a false premise to start with. So any further logic is broken. Maybe understanding the load that you're presenting to the power supply might be helpful? Class-a should be asking the same from the PSU regardless its actual output to the amplifier, so not sure where capacitance helps bass unless you're sitting on clipping (regardless the frequency) or have miserable PSRR (also a definite possibility with many of the common class-A amps). Class-d are very efficient, so their output currents follow closely with output power (variable).

PSUD2

Play with this and start asking yourself how much your power supply is sagging under high output. And how long it's being asked to output a heavy load. You're already starting from 10,000 uF, right? Not a lot of ground left to be gained.
 
Class-a should be asking the same from the PSU regardless its actual output to the amplifier, so not sure where capacitance helps bass unless you're sitting on clipping (regardless the frequency) or have miserable PSRR (also a definite possibility with many of the common class-A amps).

A common misunderstanding of classA. Only a subset of classA amps presents an invariant load to its PSU.
 
Show me a case where bass is improved by non-pathologically low amounts of capacitance. We're starting from 10,000 uF on a linear PSU roughly giving a 50v rail if I'm remembering correctly. ;)

Heck, show it in general, with any musical waveform. But start a new thread, since it's an utter waste of time here.

P.S. you're doing your infinitely obnoxious pedantry which is about 95% of the way to trolling.
 
Show me a case where bass is improved by non-pathologically low amounts of capacitance.

Classic deflection. You made the claim of 'bunkum', its for you to support it.

P.S. you're doing your infinitely obnoxious pedantry which is about 95% of the way to trolling.

If my first sentence in this response supplies the missing 5% there's a 'report post' facility you can use (bottom left).