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1 bit DAC launched by TOPPING

Blockader

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It depends on complexity of algorithm you are using and if PEQ is the only thing. When already running some DSP on computer, why not to use it also for room eq convolution or for example 5.1 to stereo. You can be interested in using anything from VST plugin world ... for example I like Goodherz CanOpener VST plugin for headphone crossfeed. Not so light on processing ... All DSP in modern players is running in 32 or 64bit floating point resolution including VST plugins. So it is rather about the basic question: Do you enter the computer DSP world, or not?
*Not so light on processing* doesn't mean that it requires 64 bit float points calculations. They are different things. For instance, handling a million coefficients for polynomial fitting isn't about needing longer floating-point numbers. The real heavy lifting, where the bulk of computing power goes, is into modifying matrices in DSP design. Using 64-bit floats doesn't necessarily simplify or improve these matrix adjustments.

comparison.jpg

Here's a savitzky golay filter I designed vs Matlab's savgol filter output. The filter I designed was for an embedded device, so the device is limited to single precision. Matlab uses double precision.

The differences are in worst case at -120db.
 
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bogi

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The differences are in worst case at -120db.
One may combine more DSP processes, including long convolutions. I like when noise coming from digital processing appears below DAC analog noise floor, so it stays unmeasurable. That's the point where higher bit resolution or floating point format helps. I am not going to debate with you what may be audible, keep your position.
 

fatoldgit

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fail!!

Both sentences use the term "function". Function in the 1st instance is related to PEQ and therefore the use of the term function in the 2nd instance qualifies/ties the USB input to PEQ (i.e. PEQ is only available on USB).

To get the other GPT interpretation the 2nd sentence would have to use the word "resolution" to tie it to "192/32" and not PEQ.

So unless, due to mis-translation from native Chinese statements into their English marketing equivs , PEQ is only available on USB.

Peter
 

Rednaxela

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Both sentences use the term "function". Function in the 1st instance is related to PEQ and therefore the use of the term function in the 2nd instance qualifies/ties the USB input to PEQ (i.e. PEQ is only available on USB).
Agree. Strictly speaking that’s how it should be read.

To get the other GPT interpretation the 2nd sentence would have to use the word "resolution" to tie it to "192/32" and not PEQ.
If Topping told us that the second ‘function’ was meant to include the highest supported bandwidth mentioned in the first sentence, I would probably say: I see what you mean - PEQ@192/32. Wouldn’t you?

So unless, due to mis-translation from native Chinese statements into their English marketing equivs , PEQ is only available on USB.
FWIW, here you find the original statement and one auto translation. Not sure what to conclude from it though. It says ‘port’ in the second sentence which is a bit mysterious.
 

DLS79

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FWIW, here you find the original statement and one auto translation. Not sure what to conclude from it though. It says ‘port’ in the second sentence which is a bit mysterious.

Apos has this English version on their product page.

apos-audio-topping-dac-digital-to-analog-converter-topping-d50-iii-desktop-dac-40021151449324_800x.jpg


Imo no matter how you look at it, it could have been better written.

I personally would have written it like this.
PEQ functionality is only supported via USB input. PEQ functionality is limited to 32 bit or less, and a frequency of 192kHz or less.
 

Martin

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"Exciting news!
We're thrilled to offer an amazing combo that won't take up much space. Check out our superior-performing plates, D50 III and A50 III, at the unbeatable prices of US$229 and US$199 respectively." Topping on fb

Edit: D50 III is out
"SHENZHENAUDIO5" gives 5 USD rebate

That's a hard pass if they are still using OLED screens. I know from experience, they become unreadable after several months of continuous use.

Martin
 

mocenigo

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Well according to Tambaqui user manual, final conversion is at 1-bit 100MHz.

Sounds like it ends up as DSD to me...

1bit SDM = DSD

The part you quoted by Bruno is previous step, not final step, according to his own schematic
View attachment 355804

The process that Bruno himself desribes if at the right of the part you circled in red, and it is essentially a low-pass filter on the 100Mhz done in the digital domain. So, it is not a pure 100Mhz 1bit and also not a pure 5-bit 3.125Mhz, but another of those genius ideas by Bruno Putzeys, and you can view it as both.
 

beeface

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Why would I want a 1 bit DAC when most audio is 16 bit or even 24 bit?
 

escalibur

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Topping is sending Amir a DAC 50 III, so a review is forthcominig.
It will probalby as boringly good as current 'good enough' DACs can be. I really wish Topping could release more DAC & amp combos (fully balanced / no nonesense/barebone features models / 110% forcus on Q/A control and durability / more color options apart from black / silver / extra slim models etc etc).
 

mocenigo

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Inside the circle it literally says 1-bit

I dont know how many pure or unpure types of 1-bit there are but Bruno's schematic says 1-bit

The output of the 7th order filter is a 1-bit stream. Nobody disputes that.

What is done later, however, implicitly processes it further: There are 32 1-bit converters that are clocked at 3.125Mhz and each switches about 1/10^8 sec later than the previous. At each tick of the 100Mhz clock, each converter polls a bit from the stream and keeps it for 32 clock ticks. Each bit is kept at the same value. The outputs of the 32 converters is then added together. The result is an adding filter (a trivial form of FIR) with all weights equal to one and of length 32. The output is a 33-level value (from 0 to 32), which is just a little bit above 5-bit. Since this value may change at each tick of the 100Mhz clock, it is not exactly a 3.125Mhz converter, not is it a generic 5-bit converter, but the hardwar after the 7th orer filter is not a vanilla 100 Mhz, 1-bit DAC either.

You can of course say that it is also "just one way" to convert a 100mhz 1-bit DS stream. But it is definitely not the usual way to do that.
 

escalibur

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Except that this one has hardware PEQ, something that ASR members have been asking for for years, from brands like Topping and SMSL.
I meant the measurements, not the extra features. PEQ will be appriciated feature by some.
 
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