Need new efficient amp for off grid solar set up

[jedics]

Hi all, looking for advice after much reading, I have an Azur 540R that is too power hungry to use in winter (even standby uses about 30w), it runs two orpheus passive speakers and a REL T3 Sub. Im looking at a Douk A5 because it has a high pass dial so I can run just my speakers by themselves 90% of the time and then turn on the sub and adjust the lowpass when I want. The only thing its missing is a headphone out for my HD600's which lead me to the Loxjie A30 but that I believe doesnt have a high pass so I would be doubling up the bass from my speakers and sub at the same time.

Is there a way to blend them by adjusting the REL to something acceptable or another solution entirely?

thanks

 

[staticV3]

Is there a way to blend them by adjusting the REL to something acceptable or another solution entirely?

Yes. You can run your Orpheus speakers full-range, then adjust your REL's low pass filter to match the Orpheus' natural bass roll-off.

 

[hollis]

If you really want to optimize for solar consider a car audio amp built to be used at 12v. The 12v to 120v inverter kills a ton of efficiency.

 

[TobyJ]

If your off grid setup can manage 24v dc output, then something like this could work: https://fosiaudio.com/products/bt30...-power-amplifier-with-bass-and-treble-control

I use this from a 12v dc battery - works a treat (but doesn't have a sub out, so no good for you) https://ebay.us/m/VYTjHh

As per @hollis, switching from an amp that required AC input to one which would take a DC input made a huge difference in terms of the amount of time I could play for. The AC amp would play for 8-9 hours from a totally full leisure battery. The DC input amp would play for nearly 50 hours.

 

[Matias]

The 12v to 120v inverter kills a ton of efficiency.

Really? Home inverters are usually rated 97-98% efficient AFAIK.

 

[Chrispy]

You could unplug the amp and sub when not in use to save some power, too.

 

[jedics]

If you really want to optimize for solar consider a car audio amp built to be used at 12v. The 12v to 120v inverter kills a ton of efficiency.

True, I might have looked into that area more if I thought of it, bought a calls D douk A5 because it was the only thing with a a high pass.

 

[jedics]

You could unplug the amp and sub when not in use to save some power, too.

Yeh I have all the hungry stuff on a board with a switch but that causes my Azur 540r to trigger my inverters overload protection if I dont leave it plugged in for at least a few minutes before I actually turn it on (probably to do with its capacitors), then it uses a lot of power, it just all added up to me not using it much and listening to crappy laptop speakers more than anything else. The Douk A5 I just bought uses .2w in standby and 4w turned on.

 

[Chrispy]

Yeh I have all the hungry stuff on a board with a switch but that causes my Azur 540r to trigger my inverters overload protection if I dont leave it plugged in for at least a few minutes before I actually turn it on (probably to do with its capacitors), then it uses a lot of power, it just all added up to me not using it much and listening to crappy laptop speakers more than anything else. The Douk A5 I just bought uses .2w in standby and 4w turned on.

I like the idea of direct DC power to avoid the conversions.

 

[TobyJ]

True, I might have looked into that area more if I thought of it, bought a calls D douk A5 because it was the only thing with a a high pass.

You can also power the Douk directly with DC, from your solar set up, if you can find a way to get 24v from your battery (?) directly to the amp.

Even if you can't get 24v to it, it may accept a lower voltage (and have a lower volume output as a result). Tho you should check with more knowledgeable people than me whether you can potentially harm the amp by feeding it a lower voltage...

 

[jedics]

You can also power the Douk directly with DC, from your solar set up, if you can find a way to get 24v from your battery (?) directly to the amp.

Even if you can't get 24v to it, it may accept a lower voltage (and have a lower volume output as a result). Tho you should check with more knowledgeable people than me whether you can potentially harm the amp by feeding it a lower voltage...

Yes I could give it 27v from my batteries but that would be a substantial drop in power going from the 32v included supply which might be ok, but I saw a reviewer measure how much power it uses, plugged in but switched off .3w turned on 3 or 4 watts. I am bound to forget to switch it off so I guess it might be worth testing that out. How much of that 3 or 4 watts do you think I would save if I wire it directly?

 

[TobyJ]

Yes I could give it 27v from my batteries but that would be a substantial drop in power going from the 32v included supply which might be ok, but I saw a reviewer measure how much power it uses, plugged in but switched off .3w turned on 3 or 4 watts. I am bound to forget to switch it off so I guess it might be worth testing that out. How much of that 3 or 4 watts do you think I would save if I wire it directly?

I've got no idea.

But if it's not too much of a faff, you could do a test to find out. I'd be v interested to see the results.

(Partly because it would tell me how much the 5x greater power efficiency i experienced was down to switching from a class AB amp to a class D one, vs the switch from AC to DC power. My switch involved both of these factors....)

 

[AnalogSteph]

It has to be said that the average DC/DC converter is not galvanically isolated, so beware of ground loops when using unbalanced interconnects or go all balanced. Car audio amps usually have some form of mitigation built-in.

 

[jedics]

It has to be said that the average DC/DC converter is not galvanically isolated, so beware of ground loops when using unbalanced interconnects or go all balanced. Car audio amps usually have some form of mitigation built-in.

Saw a video, guy measured .3w plugged in and turned off. 3 to 4w switched on. I dont have anything to measure accurate 24v use but I imagine about 2w of switched on not powering anything will be my ball park usage. Running at higher volumes I estimate 80w max without sub and more like 30/40w at all day listening volumes. Which means I will use it all the time instead of my laptop speakers