...at the video Chord put together: https://chordelectronics.co.uk/technology-explained/chord-dac-video/ The example shown there is 10e pulse array, but is of course simplified. The bit depth is more complex - the OP from the noise shaper truncator is 7 bits - but the feedback path back to the...

Yes the number of pulse array elements relate to each channel only.

Absolutely not! Dave took over 2 man years, I am certainly not about to start doing that again! Got Davina and the Power Pulse Array amps to do and that will keep me busy for the next few years. Yes that's what the new power amp tech will be called - Power Pulse Array...

No it actually changes the gain of the OP amplifier. So with the pulse array at max output, you will get just over 3v RMS in low gain, and 9.3v RMS in high gain, both with max output from the pulse array. It's just I have calibrated the volume control to tell you what the actual output is.

Correct - the 4e pulse array on Mojo is noisier than Hugo 2s 10e.

The pulse array ADC project hasn't been suspended - indeed I will be testing out the next version next month.

DDFA did not use pulse array as it is a PWM switching output... My pulse array DACs are linear outputs, and the feedback loop with pulse array DACs is analogue only.

...greater powers, when we want to preserve transparency, then we need a DAC that has a more powerful OP stage - the DX amp that uses power pulse array. So these DAC's are pulse array, promising pulse array levels of distortion and noise, but 20W to many hundreds of Watts. The DX amp can be a...

All the DACs use a third overtone crystal oscillator mounted closely to the pulse array flip-flops (FF); the clock tree driving the FF is only one buffer in depth. No PLLs are employed, which damage the SQ and the measurements and do indeed require warm up time. With pulse array, you see...

The pulse array modulator module's input is 2's complement regular PCM - analogue 0 is digital 0 - this then gets converted to give 10 elements on, 10 off. It has to be regular PCM so that it can be filtered and decimated. The same process happens with the DACs too. Within the pulse array...

Davina is the code word for the ADC project notionally intended for Dave.It will be the first product to use my Pulse Array ADC. 

Well it did take me 30 years to create the M scaler... You should see some more positive news about the pulse array ADC next year.

Oddly enough I finished a prototype PCB last week that tests one of the new concepts in power pulse array - so progress is being made, if somewhat glacial!

Sure - to a greater or lesser extent. Hence my work on power pulse array - so then we shall all have our cakes and eat them... So power pulse array allows the benefits of a single DAC amplifier, but instead of the 2W we get with Dave say, I can achieve hundreds of Watts with no loss at all in...

Correct the Scarlett 8i6. Hopefully the next recording session in May will use my prototype pulse array ADC.

Sure; I used PDM (PDM is the same as DSD - it was DSD256) DACs before pulse array; indeed I invented pulse array in order to solve the SQ and measurement issues that DSD had. In the early 90s I was using multiple randomised noise shapers, and 32 element DSD conversion to analogue. In spite of...

Yes as @Rhamnetin says it's a 10 element pulse array. Do a search on Head-Fi, I have done lots of posts explaining it in detail. But in a half dozen short sentences for TT2: 1. It's delta sigma but with 300 dB noise shapers running at 104MHz. That's a billion times more small signal...

I have not tested an M scaler on non pulse array DACs - and other DAC's will see a benefit - but you would be better off upgrading the DAC first. Pulse array DAC's have much better transient timing performance anyway, as it can innately resolve 9.6 nS. R2R DAC's and conventional delta sigma/DSD...

...oscillator at 104.25 MHz. I don't bang on about fS clocks and ultra low jitter for a number of reasons: 1. Its a very complex subject. 2. Pulse array DAC's are inherently jitter immune. 3. Use of fempto clocks would degrade sound quality as they employ PLL which although improve cycle to...

Mojo 2 is a 4e pulse array, and in order to have low distortion levels, the noise shaper runs at a slower rate - hence why the noise starts rising around 100k. The noise falls at 400k due to the analogue filters attenuating the noise shaper out of band noise.

  The pulse array modulator is the digital circuit that converts the data output (6 bits) from the noise shaper into an array of PWM signals. The output from the pulse array modulator is then fed back into the noise shaper to provide the feedback for the noise shaper. The element outputs...

It has been a constant struggle to reduce the dominance effect; and my milestones when there was a big improvement or breakthrough in this area was firstly with pulse array (1995); then WTA with the DAC64 (1999); then obviously with Hugo (2014); and then finally with the M scaler (2016).

The beauty about power pulse array is that it shares the efficiency of Class D - but the output stage can be full Class A, and the signal path is completely linear. So sliding bias, or adjusting bias (it's always a very bad idea to change anything with signal) is not needed.

...Mojo both have similar depth performance - not surprising, as depth is down to small signal amplitude linearity, and Hugo 1 and Mojo have exactly the same 4e pulse array, noise shapers and internal truncators - and it is these items that determines small signal linearity and hence depth...

...was filmed (coughing fits and all) I will ask them about the video availabilty when I do the next part today. No chance to look around the show unfortunately... I will be posting both presentations on this thread later. Yesterday was about timing, today is about DAC topologies and Pulse Array.