According to Benchmark: "Both versions of Benchmark's UltraLock™ system have near-perfect jitter attenuation and they exceed the performance of the phase locked loop that is located inside the ESS converter chips."
"The 250 GHz conceptual shift register inside the UltraLock2™ system allows delivery of the audio waveform to the D/A converter with a timing error of less than 4 picoseconds. The clock ratio measuring system calculates the ratio between the incoming sample rate and the fixed-frequency 27 MHz clock that is used to generate the 211 kHz input sample rate to the ES9018 D/A chip. This system keeps all jitter-induced distortion at levels that are at least 140 dB below the music."
Benchmark also says they use upsampling to 211kHz and they overclock the DAC digital filtering: "It is important to note that the DAC2 and DAC3 converters frequency-shift the selected built-in filter by driving the converter chip at a fixed 211 kHz sample rate. This frequency shifting places the near-Nyquist region entirely above the audio band. The Benchmark upsampling system completely eliminates the time-domain errors that would have been produced by the built-in filter. The 211 kHz upsampling frequency sets the cutoff frequency of the internal filter at 105 kHz. This places the filter transition region safely above the 96 kHz Nyquist frequency of a 192 kHz input sample rate. This unique Benchmark system prevents the near-Nyquist errors that would normally be produced by the filters in the D/A converter chip."
"This unique 211 kHz upsampling system allows us to implement a filter that is optimized for minimum passband ripple instead of using the default filter in the ES9028PRO."
They do seem to be a little cagey about some of the details as to how their boxes outperform typical Sabre implementations, but measurements and listening tests seem to confirm that they do.
A Look Inside the New ES9028PRO Converter Chip and the New DAC3 - Benchmark Media Systems, Inc.
Inside the DAC2 - Part 2 - Digital Processing - Benchmark Media Systems, Inc.
Also, I read somewhere in one of the forums around here that the ESS 9028 and 9038 don't have whatever problem the old 9018 had with sometimes sounding better with ASRC turned off.
For a perhaps surprising perspective from a knowledgable source:
Fixed Coil vs. Moving Coil: Why make the jump to a different technology? | Soundsmith
All good fortune, and Happy New Year to all,
Chris
Yes - I was waiting for this reply, although I thought it would probably come
from one of the 'high priests' on this thread LoL!
In the real world, which I live in and clearly John also, there is a balance
between objective measurements and great sound.
The transformer: If you use the right transformer you will not
compromise the measurements of the DAC above a few hundred Hz. Even at
20Hz the distortion can be very very low. Use the right transformer.
Voltage mode: Well there are actually no specs for 9038 in voltage mode.
Extrapolating from specs of previous versions, there is very little compromise
in THD and DR. The DAC already has -huge DR and very low THD so we could say there is some in the bank for the purpose of better sound. Further to this 9038 has a distortion compensation capability.
No. 9038 has very low OP Z - and that is *exactly* what you want to drive
the transformer and achieve low distortion.
WRT AK4497, you and I both on this one.
I think it's a better sounding DAC.
However - John is working with 9038 and so I am giving some specific advice
to get the most out of it - objectively speaking.
Well now you are going around in circles. Clearly, my advice is specific
because I know he is an analog lover. Subjective results are preferred
over DR / THD measurements - given that these will not suffer much anyway.
T
Happy New Year to you as well, Tournesol, and to all the gang here at diyAudio.
You know you're getting old when you're spending New Year's Eve home alone, typing up invoices! Oh well, better by far than having no invoices to type up! Plus, these days I can sit here with my laptop in the sweet spot and enjoy some great music as I work.
Cheers everybody! Thanks for all the interesting reading!
You know you're getting old when you're spending New Year's Eve home alone, typing up invoices! Oh well, better by far than having no invoices to type up! Plus, these days I can sit here with my laptop in the sweet spot and enjoy some great music as I work.
Cheers everybody! Thanks for all the interesting reading!
The Benchmark DACs all use a TI SRC4392 ASRC to get to that 211 kHz rate. Whether they are still using the ASRC in the ESS chips after this or not just depends on their configuration. From what I have seen, there is no secret sauce other than their marketing description.
It is not a bad idea at all but I am sure this approach offends purists. I love that the Benchmark products get great reviews from audiophile press and owners because it makes it all the more obvious that the "purists" and other people who badmouth op-amps, conventional "sharp" roll-off reconstruction filters, and ASRC are full of it.
Full of it in what way? Some of them may have not have imagined some reproduction artifacts they don't like the sound of. In trying to figure out some causal explanation, its likely some or many of them have arrived at mistaken beliefs about some of the underlying mechanisms. I would probably agree with that.
On the other hand, if by "full of it" you mean they are imagining the existence of every low level reproduction aberration they claim to hear, that would seem unlikely.
The DAC1 used AD1896 ASRC which was the first really decent ASRC chip.
By the sound of their marketing blurb, one would think they cooked their own ASRC but you are right. I just did some searching so apologies for re-hashing all this. Does anyone know what the effective jitter rejection CF is on the SRC4392. G Marsh did some specific testing years ago.
T
A very reasonable comment, having worked with the designers of both the AD1896 and the ESS DAC for years I can say the opinions on what people hear runs a larger gamut than you might think.
Why do we continue to have mainly folks sitting in their ivory towers doing sighted listening and pontificating on what they hear as irrefutable fact. I've given up on "mistaken beliefs about some of the underlying mechanisms" with folks that should really know better.
Why? Probably various reasons.
Dedicated software that makes it convenient and doesn't take a lot of practice to get reliable results for small differences doesn't exist (although it can be done with Reaper).
Blind testing of DUT hardware devices is even more difficult. Sometimes fast switching and looping are needed. That means high quality, hi-res digital source material and very high quality DACs, and it would also be necessary to quickly switch between DUT hardware options to be compared. That might mean building two of something and modifying one at a time to compare.
Given only the above considerations, human brains when faced with such problems often construct seemingly plausible stories for the brain owners to the effect that some time-saving, low-cost shortcut should work fine.
On the other hand, if we can make it easier to people to be honest with themselves they are more likely to avail themselves of it. Not everybody will, but more will and over time it might become more the standard in some circles where it isn't now.
Another factor is that once people are firmly decided on what they believe and there is a community of like-minded supporters, it can be extremely difficult to get people to change or even to be more open-minded. For that reason there are certain topics that are banned from the forum. But even for less emotional subjects, some of the same human tribal tendencies may come into play.
Last edited:
While I wasn't there for that recording, I have heard similar cannons used in a live orchestra presentation. The loads that they used were not all that impressive. On the other hand they use a 105mm cannon to start the Marine Marathon in Washington DC, now that was impressive.
Youtube - HUGE Black Powder Cannon at Knob Creek 2012
Youtube - Loading and firing a black powder cannon
There are some "samples", just go ahead download and run fft spectrogram etc on them.
Actually I tried firing up Audacity to check the audio streams but right now my very old computer/OS is just too outdated.
Youtube - Loading and firing a black powder cannon
There are some "samples", just go ahead download and run fft spectrogram etc on them.
Actually I tried firing up Audacity to check the audio streams but right now my very old computer/OS is just too outdated.
Last edited:
- Status
- Not open for further replies.