Suggestions for a board to go with this transformer?

Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
I'd like to do an easy amp build, and I have this Avel AT/D4064 sitting on my shelf (See specs below). Can anyone recommend a class-d (or any other easy) build that would be a good fit with this in the power supply? It would need to handle 4 ohms.

Many thanks,

Bill
 

Attachments

  • Toroid.png
    Toroid.png
    70.1 KB · Views: 114
Something else to think about: I have found very few inexpensive IRS2092 based boards that will stand up to anything greater than a +/-70 V supply. They do exist but they tend to be very high power (think kW range) and thus quite expensive.

Also, with a 4 ohm load you will exceed the current available from your transformer long before you get to the voltage available. 5.1 A into a 4 ohm load is just +/- 30 V peak.

You might want to think about building some kind of voltage regulator to keep the power rail voltage sane when under light load. Theoretically the power supply sag should keep the heat dissipated in the regulators fairly low as load increases.

On the upside you will have an easy time driving a significant amount of power into an 8 ohm load if that appeals to you.
 
As recommended by the others, IRS2092 is one of very few candidates. The transformer is not ideal for 4 Ohm and a poor choice for class AB. Class D has got one important feature - it acts as a power converter (Buck) and the output current from the amplifier can exceed the current drawn from the supply. With only a single mono amplifier connected and 4 Ohm you can get around 400W! And, you need no rail regulation.
 
Last edited:
Yes Bill, it can work with 4 Ohm due to a class D amplifier (not only the IRS2092) working as a bipolar Buck converter. IRS2092 is one of the few class D drivers that allow for up to 200V supply voltage (rail-to-rail). You will have some 150V rail-to-rail. Be careful not to overheat the transformer in particular if you run two amplifiers with 4 Ohm speakers from the same transformer. Your transformer is mismatched in the sense that you have too much voltage compared to current. As IRS2092 amplifiers are often very powerful and with a high current limiter setting you won't have traditional voltage clipping before the transformer may be (current-) overloaded.

No, not a "simple rectifier/cap board". A really good symmetrical rectifier/cap board with some 2x22000uF (100V rating) and 10A rectifier. You are talking about using your 500W transformer close to its limits and 4 Ohm speakers mean higher current. Your rectifier/cap board will have to be adapted for that.
 
Last edited:
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.