[sonicxtc]

Direct Digital “power dacs”

I am really intrigued by this “new” technology of an all in one “solution” combining pre/pwr/dac into one box while preserving a pure digital signal until the output. And, I apologize if I’m not describing that accurately. This definitely seems like a “less is more” approach to digital.

I’m seeking input. Has anyone heard any of these power dacs, especially the
NuForce DDA 100? I was considering the new Mydac (just a dac), when I tripped over the NuForce. I believe NAD has a similar “type” of product, too.

I’m wondering in particular:

1) How does it compare to a dac plus amp? Particularly a dac plus digital (or class D amplifier)?

2) Is there a “better” sounding input: USB? SPDIF?

While from a gut level, I’d expect most digital sources to sound better with something like a tube pre or a tube buffer, that may just be a false assumption.

I welcome any input. Thanks.

Happy Holidays to everyone in this incredible forum.
Thank you to the mods and participants without whom none of this would exist.

I imagine this question could be posed in a few different circles, so perhaps someone will notify me if this needs to move. THANKS.

[firedog]

I've heard the NAD M2; it was good, but not great. It was a good value for the price. That is one of the big advantages of this technology - in one box you can combine several functions for a relatively low price, but at a high level and with lots of power. Supposedly the newer model NAD (less power) has improvements to the design and sounds even better.

Class D amps are NOT digital amps. It is a totally different technology to the "Direct Digital" which is a pure PWM amp. Class D amps are actually analogue amps, it's just the engineering is different than the usual A or B amps. The "D" classification means nothing other than that it comes after A, B, and C.

Inputs: totally depends on the individual implementation on each amp. The newer NAD is  supposedly a little weak on the USB input; supposedly sounds better with a good USB>SPDIF converter.

I suggest you audition one for yourself. It's still a new technology, so I imagine the companies like NAD that are going into it heavily will produce better sound with each succeeding generation of the technology.

The forum at stereo.net.au has a pretty good thread about the NAD direct digital amps.

[wisnon]

All digital amps are Class D, even if not all Class D are digital.

The big difference is that digital amps accept Digital input and do PCM to PWM DD conversion, while most Class D amps accept analogue input and use a ADC to convert directly to PWM. Then after there is a PWM to analog conversion before or at the output stage.

[mcgsxr]

Interesting - reminds me of the old Panny XR45 and other amps of 6-8 years ago.

But I am probably missing something.

[Telstar]

The technology is very keen, albeit a bit green still. Best way to shorten the signal path that i know of.

If one's likes sigma-delta dacs and mosfets of course

[JLM]

These unit make a "direct" conversion of digital inputs and amplifies for feeding passive speakers.  And yes, being a one box solution should offer quite high value.

The upside is a very direct/pure/clean signal path.  Sound typically has been described as dynamic coming from total black background.

The downside is no analog inputs or signal "conditioning" (like tube buffers) accommodated.

The only negative I've read of is a a recent 6moons review opened serious sound quality issues at lower volume settings with the NuForce DDA-100 (even though stellar comments have come from all other quarters).