TDA7492 Amp

That is tragic that you did not cover the HV leads in the cap bank. I have cats and would never leave them exposed. They are like children and mine are 15 and 18 years old.

The 7492, 7498, and TPA3116 are class D pulse width modulated amp with greater than 90% efficiency. Short transients probably flow more than the amps rating of the SMPS via the power rail caps. That is why low ESR caps like OSCON's are good - they provide deeper reserves. Class A on the other hand run hottest or full power all the time and burn off unused power to the heatsink. When music power is at its greatest, less is burned off in the heatsink, but the efficiency is very low, probably 10%? So to flow 5A you need a supply capable of providing 50A! The transistors on the 3116 are either fully on or off, and so do not waste much as heat.

The IRS2092 class D amps are a different topology and use external scalable mosfets to do the switching so you can scale up to kW. They also have a feedback loop so have even more control.
 
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Got the new toy from the mail today.

This is the TDA7498E, rated up to 160W per channel, shipped with a 36V power brick.
Cool!
 

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I received my order of the 7498 amp (the one with cyclindrical inductors) . Sadly, the packaging was totally inadequate. The shield of one of the inductor on the edge of the board was completely demolished (to many smaller pieces). I have to contact the EBay vendor for a resolution. Waited for almost 4 weeks. Sigh.......

Regards,
 
Beautiful amp! How much for both?m

That is an impressive brick!

It was $77 shipped to my door COD.

First impressions:

- I was impressed with the packaging. It came in a sealed plastic bag, wrapped in 3 layers of bubble wrap, in a cardboard box, with the foam inserts inside like in the pictures.

- Took out the parts, the amp and the "brick". True, the power brick is quite large. Rated at 36V.

- The amp looked very nice at first, but the volume button is just cheap plastic that rubs inside, creating some friction sound, and feels pretty crappy.

- The brick seemed DOA as it wouldn't power up the amp. The LED on the brick turned on, but the amp didn't.

- I took out my 19V power and plugged it in, the amp fired up. One thing that will need some getting used to:
When idle, the amp's LED is green. When turned on, the lamp LED is red!
Also, the power is on when the button is pressed out, and off/idle when the power button is pressed in. Maybe they wired the switch inverted!

- I only tested it with my sub and it worked ok. Didn't have time to test with my TABAQs yet.

- the power brick problem seem to be coming from the end connector. It looks to be too big for the amp's input connector. I used a multimeter and I was able to get 36V, but the amp can't seem to see it. I think I will need to cut it off and use a smaller one, something like the smaller one on my 19V power brick, which works fine.
 
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Too bad about all the issues. The knob looks like aluminum plated plastic at least - typical volume knob but the rub makes it feel cheap since not butter smooth. The button does say standby, so green is standby. That is lame that the connector on the 36v brick is not compatible. What amp rating does brick have?

To be fair, $76 is a great price if it works.
 
That looks good.

Yes, it's official... my power brick is DOA. It's not just the connector. I can't get any juice anymore.

I've contacted the seller, we'll see how it goes.

Until I get news, I won't attempt to open up the brick... in case of warranty issues.
 
Guess what, I contacted the EBAY vendor that I bought the amp from and attached a few pictures of the damaged board, I got a refund right away. No questions asked. Did not even ask me to send back the board!!

That is good new. I made videos on demand and shot a lot of pictures. I just did one mistake. I approved to have picked up the goods. But that was the same as aproving the product so no help from aliexpress either. From now on I only confirm receiving items after days of testing.