Non Oversampling Vs Oversampling

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HI all,

It would be interesting to be able to change from non-oversampling to 2, 4,8 oversampling without having to re solder, etc.
For instance the Marantz CD4000 operates in 4 times oversampling (through the SAA7378 decoder) and I would like to hear how non-oversampling would sound on this CDP before I embarked on a non-os project.

I have downloaded software from which should allow a PC to communicate via DSA protocol with any decoder, digital filter using this protocol - so you can completely control the CDP - play any track, change DAC format, etc

But I have not got it working yet - the software seems to work ok but I suspect that my cable connections are wrong - or Windows is wobbly? All instructions for wiring the cable and using the software are given in the links below.

Lets see if we can get this working and have a very interesting tool for experimenting with our CDP's

The link is

and the software is at

Take a spectrum analyzer to the output of any digital circuit. There are "birdies" all over the place in low order filters. The steep o/s types get rid of it.

Example: say you have a 10 kHz signal. There will be a"birdie" at around 34 kHz.

Wadia is the best example of this problem. The SAA7220 isn't that great either. Probably due to the zero in the transfer function they put there to cancel out one of the 3 poles in the post-filter. No a good idea.

NON-OS vs. OS debate

Hi Jocko,
But you accept severe ringing and overshoot on a square wave of 1kHz right in the middle of the audioband?!:) {no joke}.
The non oversampling DAC has a perfect square wave!:)
Paul McGowan once said: <B><I>"If we submitted an analogue amplifier with the kind of square-wave response that CD manufacturers proudly publish, we'd be laughed off the face of the earth."</B></I> the Absolute Sound, Vol 10, # 39, 1985.:p
But what does this ultrasonic garbage sound like?

BAD, that is why we call it garbage. Audio circuits are non-linear (that distorting for those in Rio Linda) at RF frequencies.

"If we submitted an analogue amplifier with the kind of square-wave response that CD manufacturers proudly publish, we'd be laughed off the face of the earth." the Absolute Sound, Vol 10, # 39, 1985

And yet PS audio marketed a DAC after that and I believe Paul McGowan has not left the planet!

I really don't understand this retro frenzy for non oversampling DACs. The new DACs sound and measure better. Why the hell does everybody think oversampling was invented? If you want to do something "retro chic" go design a 6SN7 into something. That way Jocko can stop ranting about this and go rant about something else.

NON-OS software

I just started this thread because I thought ther was a quick and easy way (namely software control) to hear for myself what non-os sounds like. I am able to make up my own mind about waht sounds good and what sounds bad.

So maybe we could get back to the thread

Has anybody tried this software - if so please respond. I am interested in following this independent of others opinions whoever well informed they are - after all this is what the hobby is about

Harry, Have you experimented with non OS yourself???

I was also very sceptical about that and only browsed the DAC schematics which were oversampled, digitally filtered etc. etc. and skipped the minimalistic type ones.

Then one of my friends did a project with CD-Pro transport and TDA1541 (non OS). There was something in the sound that dropped my mouth open when I first heard it. I had tried to create a slid and 3 dimensional soundstage tweaking my Marantz CD67 for about two years, but his project managed to top mine by a huge margin with version 1 !!!

After that I have heard other non OS projects (CS8412 + TDA1543 and my own PCM1702 project etc.) and all these share the same beauty regarding the "air quitar factor" and depth in the soundstage. I consider these qualities to be very important and if these designs make it possible and the rest of my system (JLH96 or LCAudio The End Millennium amps and Dynaudio speakers) handles it without any noticeable problems then I consider it a solution worth to try.

On the techical side, if this is done over I2S interface as jkeny suggest, it creates a very simple and short signal chain. That will make it simpler to run data tracks, creates less problems with earthing, better for clock distribution etc. All this might well make it more suitable for DIY projects as an advanced DAC with latest techniques will be very difficult to build as there are so many factors in circuit design and PCB design which, if not done right, might create a lot of problems and the advantages are thus nullified....


Hi Ergo,
I agree 100% with you. My NON-OS KWAK- DAC blew the Theta V DAC of my friend straight away! And that was with four AD1851. Now it is even better with two AD1865N-K and asynchronous reclocking. The latter technique also accused of being a "technically incorrect "solution; haha!, but also giving better sound!:)
I was sceptical too but sometimes I can't withstand to do some silly experiments.....and let my ears decide.......:)

I don't know anything about software but if you have a Philips transport you can very easily use the TDA1541AS1 without gluelogic.
If you wish to use a Analog Devices DAC use there Application Note 207. Especially the Philips CD960 is very easily to convert to NON-OS. I have a friend in Taiwan who installed the KWAK-CLOCK and the NON-OS mod in less than a hour.:)
I find the Dasy-laser website VERY confusing:confused:
Since I haven't alienated everyone........ YET.............! [joke]

I have been working on digital audio since '87. I don't have to listen to it because I know it will sound like a Wadia. If that is the sound you like, then go buy a used one. I'm sure they can be had cheap. Then you can take it apart and learn how bit shifting works, and do this parallel DAC thing the right way. Maybe if we ask nice, my old buddy "Toslink" will post the schematics to save you the hassle.

The people I know that still do this full-time think this is the silliest thing they have heard of. Because they have heard the Wadias, the Thetas (parts farm designed by a Scientologist), and all the other "gold-plated turds". They are more concerned as to which works better: Crystal delta-sigma or Burr-Brown linear DAC setups.

Maybe I'm just lucky: I have clean power supplies, good grounding, and an I/V stage that does not use an op-amp. I know what my designs sound like, as do numerous audiophiles who quietly keep the secret on who made it sound so good.

Peace, man,

Jocko, can you explain

I listened to Mark Levinson separate DAC + transport in non-upsampled mode and compared it to my Philips 962SA SACD player in red book mode.

The philips supposedly has ultra-low jitter, muse fine gold caps and good burr-brown op-amps and the rest of audiophilie doodah, except a separate power supply for each stage.

Now, the listening test:

I was never a believer in audible differences between cd players, because I hadn't heard any remarkable differences.

But on that listening the differences were very obvious:

ML was more calm, less harsh, less grit and much more pleasant to listen to. No listening fatigue. Still it resolved all the same detail as the Philips.

Philips had more harshness, less bass definition, higher noise on some tracks and harpsicord plucks tended to decay much, much faster than on the ML.

I was totally flabbergasted to hear such big differences. Me, a completely untrained and inexperienced listener!

So, now that I've heard a player that has no harshness, what should I do?

How would I even start to upgrade my player to be less harsh on cd playback.

I don't want/need Mark Levinson level playback - I just want sound that I can enjoy.

Any and all tips are welcome.

Ergo, Elso,
I agree, I pay attention to expressed opinions from people who actually listen to the sound and judge for themselves not base their opinions on technical grounds alone.

Thanks for your input. The 4 times oversampling is actually done in the SAA7378 decoder so changing the DAC won't help until I can resolve this. The SAA7378 chip performs lots of functions including allowing the ability to read CDR & CDRW discs. I am reluctant to change this also.
All I really wanted was to form a group of people who would download and experiment with this software to get it working & thereby have a software tool for non-os experimentation in CDPs using DSA protocol (Philips CDPs only?)


Hi Halcyon,
With the asynchronous reclocking 95 % of the harshness is gone. Also the Wildmonkeysects loopfilter does a lot and using the low noise +5V supply for the PLL. Will try the CS8414 shortly, lets see what that brings.
But if your ears are very senstive to this issue use the TDA1541AS!. This one has <B>ASOLUTELY</B> no harshness, but I miss the sparkle and bass power of the AD.:)

I don't have the magic answer. I can tell you that exectution makes all the difference.

Example: Magnavox CDB-472. Look at the schematic......looks ok......everything going to the right place.

Then look at the actual circuit board. The grounding is horrible. Fix it, and it sounds much better. When I first saw one, I screamed that I would have fired the junior engineer that screwed up the grounding.

Then it dawned on autorouter did it. No wonder it sounded rotten.

Some designs are more tolerable of poor execution than others. Some there is no hope for. Some sound astouding, but only if done right.

Just because a "high-end" company did it, is no reason to assume that they really did it any better than a giant international conglomerate that doesn't care less.

I've looked inside all of them. You would be surprised who does it right, and who gets by on reputation.

Digital done right

Why should he help others sell DACs? Is he a reviewer now?
Ask him the design approaches that make a good design. I though the name of this forum was Do It Yourself Audio.......


P.S. I think the Wadia blows also. I modified one to sound better by taking parts out of the SPDIF frount end to get the reflections down! I own two DACs by the way. One from Scott Nixon and one from Jocko.
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