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Power adapter/supply for Mirage LFX-3 crossover

I need to replace the power adapter for my Mirage LFX-3 crossover. The crossover is connected to dual Mirage BPSS-210 subwoofers.
The supplied wall wart adapter puts out 18 volts AC. However, the back of the crossover where the output of the adapter goes indicated that it takes 16 volts AC. See photo.
So, looking for a replacement power supply, should I look for a 18 volt AC output or a 16 volt AC output. Aside from 2 volts, what is the difference between using 18 volt or 16 volt supply? Is there a downside or an upside to using 18 volts if 16 volts is specified by design. Why? I assume that Mirage thought that 18 volts was OK (probably what was available off the shelf). But, I would prefer to do what is best rather than what is potentially just OK. I would ask Mirage, but they don’t really exist.
Thanks for the help!

lotusm50
willcycle
46 posts
 

I think the reason for the 2V discrepancy is once the transformer is loaded down the secondary voltage drops to near 16.  If you decide to go with a higher rated transformer it should be closer to 16V.

imhififan's avatar
imhififan
2,181 posts
 

I will opt for a 16VAC 1A rated Walmart. if you look at the schematic, the 4700uF filter cap is rated 25V which is a bit too low for 18VAC after rectified (18VAC X 1.414 - 1.4 = 24VDC), and the 7815 regulator only required 17V input voltage, anything higher will be dissipate as heat.

lotusm50 OP
31 posts
 

Thanks.  I think that is how I am going to go with this.

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