Cyrus apa7.5 + Smartpower > Kef r500 Query

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Neil Ridiculous
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Cyrus apa7.5 + Smartpower > Kef r500 Query

Postby Neil Ridiculous » Sun Feb 11, 2018 6:04 pm

I was wondering if anyone had tried similar to what I am about to detail.

Currently I have a couple of apa7.5 units powering a pair of Kef R500s. I really like the sound.

However, I have a couple of Smartpower units that are not in use. I suppose I could sell them, as an option. Or even sell them along with the apa7.5 at some point and upgrade. There are plenty of possibilities.

This is more of an experiment out of interest though. I was wondering how it would sound if I were to hook up all four units powering the individual high and low frequency of each speaker. As below.


Use the smartpowers in mono for the treble and the apa7.5s for bass, as per diagram. That would exceed the recommended rating for the speakers, though I never listen to music at crazy volumes anyway. I could always test it out easily enough, but I would need to buy a few extra interconnects first.

Has anyone tried similar in which the total power output would be quite significantly higher than recommended speaker ratings?

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Re: Cyrus apa7.5 + Smartpower > Kef r500 Query

Postby mojo » Mon Feb 12, 2018 1:01 am

I've experimented with similar things and it's often interesting to do. I don't think the power rating will be an issue, provided you don't crank the volume up too much - it's generally more risky to use an under-powered amp at high volume than an over-powered amp, because of the risk of clipping.

Despite what Cyrus say about "gain matching", their amps do not all have exactly the same gain, so you may find that doing this alters the low:high frequency balance slightly, but the effect is likely to be subtle.

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Re: Cyrus apa7.5 + Smartpower > Kef r500 Query

Postby angelface » Mon Feb 12, 2018 1:29 pm

Do try putting the monos on treble too as it is not just power that is better than the smarts.

Many have tried this type of thing but most end up upgrading to a single pair of even better monos.
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