200W IRS2092 Amp for $20

[troystg]

Well unfortunately I have been travelling for work and have not been back home for more than 24 hrs so the short answer is...

Not yet...

Got home today at 4 pm, mowed the yard and will be napping in 10 minutes. Have to be on the road again at midnight. No rest for the wicked.... [emoji16]

 

[chermann]

for information.


the used power supply is:
500W 48V LLC ALIEXPRESS

thx hans

 

[xrk971]

That's a very cost effective PSU. Can you hear any noise artifacts from the PSU?

 

[hansueli]

Some mesurements. One amp 4ohm.


aprox 500W at 230V socket with output like 1st picture. Supply voltage is to low for it.


I can go without any problems to 95V pkpk with 4ohm load.

Mesured load resistance is 3.9ohm.

 

[Peterma]

I have just soldered an L-20D amp but i have noticed that the 2 surface mount capacitors on the underside have not been soldered in, do they need to be there and if so what value are they?, i have vers4 pcbs.

thanks

 

[xrk971]

Thanks for the measurements. Can you please explain what the different traces are? I am trying to understand the output ripple at load. I assume one trace is amp output into 8ohms and the noisy one is the SMPS voltage at the amp input? About 2Vpp?

Tha FLIR is a nice toy - what doe those cost?

 

[hansueli]

xrk971 its 4ohm load (later i made 8ohm with both channel driven).
Exactly yellow output of amp and blue is one rail from psu. I can't mesure both at same time when I want to have the amp output too.


I payet CHF 360 for the Flir one PRO with 3 years warranty (NEW)

 

[Peterma]

I have just soldered an L-20D amp but i have noticed that the 2 surface mount capacitors on the underside have not been soldered in, do they need to be there and if so what value are they?, i have vers4 pcbs.

thanks

 

[hansueli]

Hello guy,

I am thinking of buying irs2053 amplifier. It's a 3 channel version of irs2092.

Is this amp also a good base?

 

[chermann]

I have just soldered an L-20D amp but i have noticed that the 2 surface mount capacitors on the underside have not been soldered in, do they need to be there and if so what value are they?, i have vers4 pcbs.

thanks

Hi Peter

i guess without pic nobody can help you. pcb is big enough - so no idea where the smd caps are missing? 😉

chris

 

[chermann]

Hello guy,

I am thinking of buying irs2053 amplifier. It's a 3 channel version of irs2092.

Is this amp also a good base?

Hi Hans

personally no idea. i just found that:
https://www.diyaudio.com/forums/class-d/236723-irs2053-irf6665-120w-3ch-class.html#post3506889
chris

 

[troystg]

About the original post, does anyone know if that amp has balanced inputs?

Or know of another similar that does have balanced inputs?

 

[hansueli]

What do you think about this schematic?









I have an ampboard with 6 of them :-D


I'am planing to use it with my 500W48v china LLC supply :-D

 

[hansueli]

So I modded the board.


Change inductor and some capacitors.


I have a problem: amp is very noisy and very loud. Also on min volume its very very loud and noisy.


Befor demounting from system it worked normal. What could be the reason?


Power supply was 30V and yet its 48V

 

[Rick PA Stadel]

Hi hansueli,

I'd like to offer an opinion but your schematic piece in post #453 is really hard to read. Is there a possibility you could try posting it another way?

It looks like the big 6-channel board says +/-35V on those 8 pins, second from the left rear edge.(?) Wouldn't powering it with +/-48V require some redesign?

Regards,
Rick

 

[hansueli]

Hi Rick


Thanks for your answer.


So i will repost the schematic

irs2092-1 — imgbb.com




Yes I change some caps for higher voltage.
The system works. I need to place heatsink on 12V VCC for IC power... From 48V to 12V is much more heat than from 30V to 12V.
AMD08 in schematic also got hot. Why?




I put 2.2k in the signal rail with 24k to ground and left the 10uF signal cap. But still very noisy and too loud.

 

[Rick PA Stadel]

Much better. Thanks.

Studying it now.

One thing straight-away -- your outputs, the IRF6645's, are only rated 100V. May not be a problem right away, but that would be too close for my comfort when you have +/-48V rails. Wouldn't give even a tiny safety margin for, say, the spikes resulting from even a small amount of leakage inductance.

Can you describe the 'noise' the amp is making?

Cheers

 

[Rick PA Stadel]

If there are any 78xx or 79xx-series regulators, they're not going to like >40V, either.

-R

 

[hansueli]

I have -5V and one 12V feeded by auxiliary output (+-15V).


And VCC regulator has some resistor and transistor for attenuate 48V to 12V for the chips.


Noise is like to high amplification and you can hear it really loud on speaker.


I don't know how to explain.




I can modd my supply for 40V if its more safe :-D

 

[troystg]

I just finished this today and would like to test it before I put it on some “good” speakers. What do you suggest for testing?

1. Test for DC on the outputs.
2. ?
3. ?