what is AC dual 24V?

[Numnuts]

This might be extremely simple.
i have a small audio amplifier and the specifications for it says it needs duel 24vac
"Working Voltage: AC dual 18-24V (Recommended Dual 24V)"

this is the amplifier (specs are listed here) https://www.ebay.com.au/itm/384186733165

what (in layman terms) is Dual AC?

and how could i power it from 24vDC?

 

[Bluejets]

Rather than try to explain the layout, check out the drawing below.





or this........ there are others as well..........

 

[bertus]

Hello,

@Numnuts , As the rectifier and buffer caps are on the board, you will need a dual AC transformer as input:

ILP has a series of transformers that can be used.
Use a high enough power rating for the used amplifier.

Bertus

 

[Audioguru]

Why does this audio amplifier have no audio specs? Is it because it is no-name-brand and is sold on ebay by people who know nothing about audio amplifiers?
The ad says 100W x 2. Is that peak Whats at horrible clipping distortion so its real output is only 20 Watts x 2 with low distortion?
Distortion is an important audio spec but it is not mentioned like the frequency response is also not mentioned.

 

[Numnuts]

Hello,

@Numnuts , As the rectifier and buffer caps are on the board, you will need a dual AC transformer as input:
View attachment 51922
ILP has a series of transformers that can be used.
Use a high enough power rating for the used amplifier.

Bertus

what would be the easiest way to run this from DC?
the plan is be to run it on 2 12v batterys in series

 

[Martaine2005]

You can power this with DC.
You will have a voltage drop from the bridge rectifier.
You can connect your DC input directly where the bridge DC + and - were connected to avoid the diode drop..
Without any specifications, who knows whether batteries can or will power the device for any specific time.
Trial and error is probably your only option.

Martin

 

[bertus]

Hello,

The amplifier need a dual powersupply.
As the expected power input is 24 Volts AC, there will be about 33 Volts on the amplifier.
When you use one 12 volts battery for the plus side and one for the minus side, the power will be much less than the maximum power.

Bertus

 

[Audioguru]

If the amplifier is class-AB type then each stereo channel produces about 12W into 8 ohms (20W into 4 ohms) and the sub-woofer channel produces 38W into 8 ohms (63W into 4 ohms) when the supply is 33VDC.
With a 24VDC supply, each channel will produce about 6.3W into 8 ohms (10.5W into 4 ohms) and the sub-woofer channel will produce about 20W (33W into 4 ohms).