WiiM Amp Pro
- Thread starter Chiller54
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They are switching, which means the driver is on or off. Binary. The analog output is derived from varying pulse width. The output is bandpass filtered to eliminate high frequency artifacts.
My point is, there is no crossover notch. No IM distortion. The output can theoretically be as clean as the signal from a really good DAC. I suspect it’s approaching that already at reasonable levels and with speakers that do not present unpleasant loads.
A switching amplifier can even be made as a DAC, sometimes referred to as a power DAC (or a digitally controlled switching amplifier). The technology behind is is purely analogue, still.
IMD is caused by any non-linearity, not just because of crossover effects and class D amps are still prone to them.
That's not to say I disagree with the view that class D amplifiers can be made to excellent standards and surely continue to replace linear designs.
I think we’re miscommunicating a little bit. I’m thinking that in the long run, class D will be easier and a lot cheaper to perfect. I really think, if we come back to this in 20 years, many, if not most, high quality speakers will be active and have amps with digital eq for each driver. Any shortcoming in class D will be blown away by being able to fine tune phase and frequency response for each driver. And no crossovers. This will eliminated complex loads on the amps.
Steve Woodhouse
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As time goes on, it's becoming increasingly clear that you just need drivers with low distortion, and 'ball park' flat frequency response, and EQ can even out the bumps.
As we see AI coming to the fore, room correction is going to get quicker, easier and cheaper. It will also make speaker design significantly easier, and thus quicker and cheaper.
Nothing will improve speaker design and price more than eliminating crossovers and having a DSP enabled amp for each frequency range. I figure when this is mass produced, you could do 3 way electronics for a hundred bucks. Or thirty thousand for the audiophile version. And everything in between.
Steve Woodhouse
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No, it won't. Not really.
1. Digital filters are still crossovers. Always active (of course), digital, naturally, but still crossovers.
2. Every single dynamic speaker driver already presents a reactive load (mathematically: complex impedance), more precisely an inductive load. Electrostatic loudspeakers represent a mainly capacitive load. Magnetostatic drivers are about the only ones with purely resistive impedance.
A purely inductive load can lead to a lot of heat in the class D amplifier's output filter. Admittedly, this is usually a real problem only with a woofer plus a passive low pass filter. The cure is to apply a digital low pass filter, anyway.
The extinction of passive loudspeakers has been foreseen time and time again for decades. So far it hasn't happened.
Detrimental effects of passive crossovers are real but usually exaggerated.
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Based on your post, I googled and found that high end subwoofers are often driven by BASH amps, a hybrid. Interesting.
Steve Woodhouse
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But we’ve not had cheap, easily available digital EQ until recently.
2x4 hd.... no so cheap but not so expensive
but a product, and the old models are not new and successful... the interest of peq for general public products is obvious...but arrives at the same time as the wiim a generation of dac chinoix proposing it... the "thing is launched" ;-)
the rc mode may be difficult to achieve but the wiim peq seems to be off to a good start now....
;-)
Steve Woodhouse
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I’m pretty sure I said ‘cheap’.
Considering that I can buy an Ultra for only $100 extra on the Topping D50 III, the Ultra is truly an amazing price.
certainly...Considering that I can buy an Ultra for only $100 extra on the Topping D50 III, the Ultra is truly an amazing price.
but you'll see when he's here...
have fun... ;-)
Hmm, you’re saying it’s in middle of the ground. I had mini dsp and what I can say it was so many adjustments to tweak it to your liking. It has separate hi/lo pass, individual gain/cut on each channel and my favorite different slope of filter including butterworth linkwitz riley and among others. In term of subwoofer integration on 2.1 setup, mini dsp can truly make your subwoofer total integration on main speakers.
