Oversampled DAC without digital filter vs NOS

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I'm curious how you feel the difference between long and short one. In my experience, it takes very long time (years) to recognize clearly the drawbacks and strength of each digital filter processing method. Even NEVE and SSL people were selling horrible sounding digital products for years without hesitation. ;)

I felt there was no difference between a filter with more than good enough specs and one with massive overkill. Again, specifying your filter by length is not a thing. If you want to talk about the actual parameters, then it makes sense.

If something takes years to recognize, I think you’re fooling yourself.
 
I'm curious how you feel the difference between long and short one. In my experience, it takes very long time (years) to recognize clearly the drawbacks and strength of each digital filter processing method. Even NEVE and SSL people were selling horrible sounding digital products for years without hesitation. ;)

On Neve's newer products such as Genesys Consoles, Prism are doing the digital side.

In fact I was working on one yesterday and had a brief listen afterwards through the resident Adam active 3 ways.

I'd love to be wrong - but I'm not sure filters are on their radar with these types of products. They most likely use the standard filters in the DAC chips.

The real hero, pro wise, that most are not aware of, is the late Bruce Jackson and Australian that started the original Apogee Electronics before the company was sold and started to make cookie cutter converters. At that time, Apogee had a resident mathematician programming the original Apogee filters. The DAC's also had a potted, aparently zero feedback discrete I-V. Those DAC's sounded good and were re-badged and sold by Levinson.

This was over 25 years ago, pretty impressive.

T
 
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There's no argument that a longer filter can perform better.

As far as his claims go - of course he would say that at an event like RMAF. His story and claim are dubious at best.

It's a shame, IMO, because he's got a respectable product.

When you've got an FPGA hammer, everything looks like a nail I suppose. I guess I can't fault him too much, because at least his products objectively perform well.

No meant to be offensive, but it seems that you´re criticizing him without any contradictionary evidence.

You haven´t done any sensory test to compare his product to others (or his filter approach to others), instead you´re simply assuming and believing something different.

Watts otoh talks about listening trials (without any informations about the procedures though) and measurements and simulations and at the end can point to well engineered (presumably, according to measurements available).

So, criticizing someone for not offereing hard evidence (without stating what that evidence should be) on the basis of mere belief seems a bit strange.....
 
No meant to be offensive, but it seems that you´re criticizing him without any contradictionary evidence.

You haven´t done any sensory test to compare his product to others (or his filter approach to others), instead you´re simply assuming and believing something different.

Watts otoh talks about listening trials (without any informations about the procedures though) and measurements and simulations and at the end can point to well engineered (presumably, according to measurements available).

So, criticizing someone for not offereing hard evidence (without stating what that evidence should be) on the basis of mere belief seems a bit strange.....

Those making claims can “put up or shut up”. If he wants to claim it, he should present his data. I simply have no time for unsubstantiated claims that immediately sound bogus given the track record of this snake oil filled industry. I will be glad to accept the findings if the data is presented. The burden of proof is on the man claiming you can hear something 170 dB down.

Have you worked in science? It’s not strange at all, in the real world. The only thing strange are the lengths people around here go to defend their favorite BS vendors’ unsubstantiated claims. Just to clarify, I’m not talking about you specifically or anything, just in general.
 
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Could be wrong, Marcel is the only DSP pro in this thread.

Actually I'm not, I'm an analogue, RF and mixed-signal designer. In my spare time I can play with FPGAs whenever I feel like it, but at work I'm not allowed to touch anything purely digital. (For the single-bit DAC I wrote about in another thread, I only designed the analogue/mixed-signal part, the digital stuff was done by colleagues.)
 
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If something takes years to recognize, I think you’re fooling yourself.

Yeah, whenever I read that, it invariably sounds more like a change in preference (for large effects) or a long time to convince oneself of a pet theory.

It's a good reminder, to all of us, that just because we do something for a long time, there's no guarantee we're improving in that thing, in fact we might be regressing.

This criticism laid out, I still stand by my idea that we do audio to improve our quality of life, and that takes very different roads for different people.
 
Those making claims can “put up or shut up”. If he wants to claim it, he should present his data.

If it were just about that I wouldn´t object.
As said before it is a valid point of view to state that some assertions are contradicting the current model used and that you therefore would like to see some hard evidence before accepting the new.
But of course you should be able to point out which kind of evidence is needed (iirc that is still an open question;see the other closed thread about this topic).

I simply have no time for unsubstantiated claims that immediately sound bogus given the track record of this snake oil filled industry.

That is the kind of statement i was wondering about, because it is way beyond the position mentioned above. Watts isn´t responsible for whatever "snake oil" in this industry is present.

Furthermore you were arguing with anecdotal judgments about other products using conceptually different filter designs.
Using results from an evaluation process that don´t trust to question Watt´s statements/methods based on an evaluation process that you don´t trust (although we basically have no knowledge about his methodology) seemed to be a bit strange, that was what i meant.

I will be glad to accept the findings if the data is presented. The burden of proof is on the man claiming you can hear something 170 dB down.

Wrt our discussion i´d think the main point would be the claimed superiority of his "very long filter structure" ,where we basically all seem to agree that -especially in case of the 44.1 kHz sampling frequency - longer (i.e. more sophisticated) digital filters will be beneficiary (if done propperly) while the perceptual difference would be questionable wrt the current model (of hearing).

you worked in science? It’s not strange at all, in the real world.

I hope the content posted above helps to clarify this?!
 
The real hero, pro wise, that most are not aware of, is the late Bruce Jackson and Australian that started the original Apogee Electronics before the company was sold and started to make cookie cutter converters.

This was over 25 years ago, pretty impressive.

I didn't know that Bruce is gone. We talked regularly back as far as the days of nothing but op-amp based analog filters. Last we talked he was working on some software to help his daughter deal with ADHD.
 
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Even NEVE and SSL people were selling horrible sounding digital products for years without hesitation. ;)
Well ...most of the top digital designers of SSL are the very engineers that gave us the SACD, Blue Ray and MXR1 at Sony Oxford Lab in Oxford, as SSL is just 4km away, in Kidlington.Some of them migrated to Apple as audio gurus...All the Sony engineers took Cost Down courses too :)
 
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What's the MXR1? I was aware that Oxford Digital (which later became Sony Oxford) was heavily involved in pioneering DSD (under the guidance of Peter Eastty) but the idea that their engineers gave us SACD and Bluray seems to me a bit far-fetched. Do you have any links to support this notion?
 
...BTW, I don’t think there are very many filters in commercial audio ICs that are windowed sinc. Maybe some audiophile parts using external custom filters. Everything else’s linear filters seem to be halfband.

I believe that the long discontinued Pacific Microsonic Devices commercial filter IC's - the hardware based PMD-100, and the software DSP based PMD-200, may have utilized a windowed SINC. Evidence for this is visible in the datasheet frequency response graphs, in terms of the upper band edge ripple character, for these filters.
 
Well ...most of the top digital designers of SSL are the very engineers that gave us the SACD, Blue Ray and MXR1 at Sony Oxford Lab in Oxford, as SSL is just 4km away, in Kidlington.Some of them migrated to Apple as audio gurus...All the Sony engineers took Cost Down courses too :)

I know. What I meant to say is, even for those top engineers, it took very long time to know how to design proper sounding digital filters. The digital filters built in SSL/NEVE million dollars digital consoles released in late 90's were nothing but unusable for professional music production. Try to compare the old classic Sony Oxford EQ with Equilibrium or Fabfilter, you'll notice how digital filters have been improved last 20 years! :)
 
I believe that the long discontinued Pacific Microsonic Devices commercial filter IC's - the hardware based PMD-100, and the software DSP based PMD-200, may have utilized a windowed SINC. Evidence for this is visible in the datasheet frequency response graphs, in terms of the upper band edge ripple character, for these filters.

Thanks for the tip, I’ll check it out.
 
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