Chopper vs. clasic PSU for audio.

[mneary]

A chopper power supply still receives power from the mains in 50/60 Hz bursts (100/120 half-sines per second).

But even with a storage battery, the charger will have a 50/60Hz input.

One thing you say is correct: You, with no experience, don't know why the power supply uses a 50/60Hz transformer. Those of us who are experienced in the field have offered some insight. Yet you say we are wrong. Please explain how your lack of knowledge gives you this advantage.

 

[vlad777]

Yet you say we are wrong. Please explain how your lack of knowledge gives you this advantage.

Your posts are very helpfull and thanks for replying.

I just know that processor gets clean 1.7 V with 100A and this is achieved
by chopper(several stages) that is also powered with 50/60Hz input.

**broken link removed**
{
Core 2 Extreme QX6800
(quad 2.93GHz - 2x4MB)
1.55V 155A 130W
-------
Athlon 64 X2 6400+
(dual 3.2GHz - 2x 1MB - rev. F3) 1.4V
90.4A 125W
}

 

[Nigel Goodwin]

Your posts are very helpfull and thanks for replying.

I just know that processor gets clean 1.7 V with 100A and this is achieved
by chopper(several stages) that is also powered with 50/60Hz input.

And has nothing whatsoever to do with audio amplifiers?.

The supply to the processor won't be that clean either.

The advantages of a switchmode PSU for an audio amplifier are only these:

1) Smaller

2) Lighter

3) More efficient

4) Cheaper (possibly!)

Disadvantages are:

1) More complicated

2) More likely to fail (because of 1)

3) MUCH higher noise levels (which is why they aren't used).

If there were any audible advantages then they would be common place, as already suggested your entire premise is incorrect - you're overdriving a low quality amplifier and then complaining about it.

 

[vlad777]

The advantages of a switchmode PSU for an audio amplifier are only these:

1) Smaller

2) Lighter

3) More efficient

4) Cheaper

I would add that the noise levels can be managed and I rest my case.

 

[tcmtech]

I would add that the noise levels can be managed and I rest my case.

Isn't that your whole problem now?

Are you sure you don't have a bad capacitor in your amplifiers power supply and thats why its doing what its doing? Try changing them out for something far larger and put in a bigger rectifiers as well. That will cure the ripple issue until the transformer looses from being overloaded kill it.

I don't recall you having ever mentioned what brand or model amplifier you have an issue with a so far either.

 

[Nigel Goodwin]

I would add that the noise levels can be managed and I rest my case.

Well the worlds top audio manufacturers would (and do) disagree with you.

 

[vlad777]

Isn't that your whole problem now?

I think that this thred has goon long enough but I must explane:

One thing is noise and another is PSU-s inability to give enough power.

Also I am talking in general and not refering my aiwa NSX-R37 or panasonic SA-AK25

 

[Nigel Goodwin]

I think that this thred has goon long enough but I must explane:

One thing is noise and another is PSU-s inability to give enough power.

Also I am talking in general and not refering my aiwa NSX-R37 or panasonic SA-AK25

Well you're certainly not talking in general, as you're suggesting problems which don't exist, multi-kilowatt poweramps commonly use convemtional transformers and PSU's - yet they give enough power. I've never seen an amp that didn't (unless it was total crap), nor have I ever heard of any such claims apart from your's.

If you want to build a SMPSU for an amp you are of course perfectly free to do so, but your stated reasons are likely to end in severe disappointment.

I look forward to hearing how you get on.

 

[audioguru]

High power car amplifiers use a switchmode voltage stepup converter and they don't produce the switching noise.
But since they don't have a 50Hz or 60Hz input then they don't produce 50Hz or 60Hz when they are clipping.

 

[Hero999]

True but how much louder is that signal that the 50 volts is producing?

2.5/8 = .3125 amps or about .78 watts.
25/8 = 3.125 amps or about 78 watts which is 100 times more energy.

But it's only four times louder than the ripple.

0.78W is actually quite loud.

It's the ripple rejection of the amplifier which mitigates ripple on the output.

 

[Nigel Goodwin]

High power car amplifiers use a switchmode voltage stepup converter and they don't produce the switching noise.
But since they don't have a 50Hz or 60Hz input then they don't produce 50Hz or 60Hz when they are clipping.

They do produce switching noise, which is one reason why they aren't considered high quality.