[sdiy] Wikipedia DCO article

[cheater cheater]

Remember PC Speaker? That's the grand daddy of DSD.

Stream synths can skip the lpf because they go to an integrator
anyways. harmonic content doesn't matter for an integrator.

On Wed, Jan 14, 2009 at 2:51 PM, cheater cheater <cheater00 at gmail.com> wrote:
> DSD = direct stream digital. It's the pwm-style DAC technology, there
> was even a medium created just for that, concurrently with DVD audio.
>
> basically what you do is you look at your signal, and that signal is,
> say, 8-bit-depth. So instead of an 8-bit sample in your PCM stream,
> you output eight 1-bit samples that sum up to the same amount of
> current transferred... it doesn't work that simple, but it's an ok
> explanation. Then you put it through a LPF smooth it out. Basically,
> if you look at a period of time which is around DC, the more 1's you
> have in that duration of time, the nearer to Vmax your signal will be.
> The more 0's you have in that duration of time, the nearer your signal
> will be to Vmin.
>
> Now a stream synth basically uses the same idea but instead of the
> signal going to an LPF it goes to the accumulator.
>
> HTH
> D.
>
> On Wed, Jan 14, 2009 at 2:15 PM, Tom Wiltshire <tom at electricdruid.net> wrote:
>>
>> On 14 Jan 2009, at 09:52, cheater cheater wrote:
>>
>>> Note that most DACs nowadays are DSD followed by an integrator.
>>> This means most NCO's turn out to be stream synths which means they
>>> are just a whole lot of logic followed by a  classical DCO,
>>> technically speaking.
>>> I'm saying this because I class stream synths as DCO's. Is this right?
>>> Cheers
>>> Damian
>>
>> I thought I was reasonably well informed on the topic, but I'm afraid I have
>> no idea what you're talking about.
>>
>> What's DSD? What's a "stream synth"?
>>
>> Thanks,
>> Tom
>>
>>
>>
>