[MojoAudio]

Erin makes some very good points.

But please understand that my points are intended as over simplifications for the novice and not to be used as points in a highly technical debate.

Also consider that 80% of the music we hear is in the mid-range above 100Hz and below 3KHz.

And consider the peak-to-peak voltage of a power supply is only one factor. Things like the dynamic response, ringing, and odd harmonics play a significant role in what our ears perceive as "right."

For the record, I'm not a big fan of the TDA15xx DAC chips in general. They are relatively noisy, not particularly linear, and have a "grainy" sound relative to the later 18-bit and 20-bit R-2R DAC chips.

The point I was trying to make is that in a "budget" DAC (<$500) you can get better performance from something like a Terra DAC using the TDA1543 chip than some more advanced designs because they can put the $$$ into one better single voltage external PSU and some fairly high grade output coupling caps. When you get into the >$1K price range I think there are many more favorable options using other R-2R DAC chips.

BTW, I admit I was mistaken about the TDA1543 having an S/PDIF input...remind me not to post at 3am when my cat Rufus wakes me up

Personally I'm a big fan of the 20-bit R-2R DAC chips such as the PCM63 (my personal favorite) and the AD1862. To my ears they have much less noise and grain than the older R-2R DAC chips and better articulation than the more modern "hybrid" 24-bit R-2R DAC chips.

But that is just my personal preference...some audiophiles and manufacturers prefer the sound of the TDA1541 or TDA1543...look how many highly regarded (and highly priced) DACs on that list use those chips.

As for 16/44.1 being all that is required, I don't agree. At the same time I think that 24/192 is a bit on the ridiculous side. I agree with some of the renowned recording engineers that claim somewhere around 20/96 is about the maximum playback electronics and the human ear can distinguish under the best of conditions. Of course we never get to hear things under "the best of conditions" so likely far less than 20/96 would be optimal for commercial recordings.

Consider that these LSB are rarely used on any commercial recording. See if you can actually find a commercial recording with greater than 16-bits of dynamic range despite being sold as a so-called HD 24-bit format.

So when some people argue "I can hear the difference" they are in fact hearing the difference in the modern low-noise remastering or some other factor and not the LSB above 20-bits.

I've been exhibiting at audiophile shows for nearly a decade and my favorite thing to do is to play a well recorded 16-bit Red Book recording and ask people "what resolution do you think that is?"

Most will tell you it's a 24/96 or 24/192.

When I tell them "you're listening to a 16/44.1 Red Book CD" their jaws drop in disbelief and question how it could sound as good or better than the 24/192 and DSD recordings they've heard in other rooms.

One year at RMAF we even had a contest and played a series of 16/44.1, 24/96, and 24/192 recordings requesting that people mark down the digital resolution. Prizes were awarded to "the most correct" marked on a sheet. Long story short in all the entries done over the three days of the show the best anyone got was 1 out of 5 correct. Seriously.

What does that tell you about recording, mixing, and mastering quality vs. HD file formats?

And back to topic, what does that tell you about the potential of a vintage R-2R DAC

 

[erin]

Personally I'm a big fan of the 20-bit R-2R DAC chips such as the PCM63 (my personal favorite) and the AD1862. To my ears they have much less noise and grain than the older R-2R DAC chips and better articulation than the more modern "hybrid" 24-bit R-2R DAC chips.

Based on my experience, I agree with your statement above.

As for 16/44.1 being all that is required, I don't agree.

When I tell them "you're listening to a 16/44.1 Red Book CD" their jaws drop in disbelief and question how it could sound as good or better than the 24/192 and DSD recordings they've heard in other rooms.

Based on your second comment, which is based on empirical observation, perhaps 16bit 44.1khz really is "good enough"?

My only complaint with music that I like which I think sounds "not great" from an audiophile point of view, is that it wasnt recorded or mixed or mastered very well. Like you have observed, when the musical performance is wonderful, and is backed up by excellent recording / mixing and mastering, the results are really enjoyable.

 

[Luckbad]

Has anyone modified their own Sonic Frontiers SFD-1 MKII? Sending it to Parts Connexion for the SE+ mods is cost-prohibitive.

I've poked around in there a bit and the only thing I'm worried about when pulling out the PCB is the front connections (LEDs mostly).

Those seem to have some sort of glue or similar on them.

If nobody has done it and I can't get my hands on an SE+, I'll figure out what to do about the front goop to do the mods myself.

 

[Wildcatsare1]

Hey all I’m back! Ben’s too modest to post these Articles, so I will.

https://parttimeaudiophile.com/2017/10/08/rmaf-2017-more-must-see-rooms/

http://www.theabsolutesound.com/articles/rmaf-2017-show-report-personal-portable-and-digital/

 

[AReasonableMan]

Sorry if this is a noob question, everyone. Is the Monarchy Audio M33 DAC/Pre an R2R DAC? It uses PCM64s.

 

[kvik]

M33 uses PCM63, I think. Both are Multibit (R2R), though.

 

[AReasonableMan]

M33 uses PCM63, I think. Both are Multibit (R2R), though.

Thanks

 

[yildiray]

Hi,

I'm search for original PCM1704U-K chip.I found this seller but i'm not sure.Do you know this seller or could you advice any alternative which you trust ?

https://www.ebay.com/itm/1PCS-PCM17...612046?hash=item43eaf324ce:g:ASMAAOSwZ8ZW7D4q

I will be very happy for your helps.
Best Regards

 

[erin]

Hard to say. The burr brown data sheet says the K grade chips have a white dot on them, not a giant "K"
But, someone else might know something different?
When they are selling at that price it's a good incentive to fake the "K".
It's probably a working PCM1704 normal grade though. Why do you need K grade?

 

[yildiray]

Hard to say. The burr brown data sheet says the K grade chips have a white dot on them, not a giant "K"
But, someone else might know something different?
When they are selling at that price it's a good incentive to fake the "K".
It's probably a working PCM1704 normal grade though. Why do you need K grade?

I see K grade chips are best performans of 1704s, isn't right ? Do you have any experience between J and K type of chips?

I found another vendor at Altium Ciiva: http://component.iiic.cc/index.php?main_page=product_info&products_id=1852765

Anybody know " component.iiic.cc " ?

Best Regards

 

[erin]

If you are really serious about buying genuine K grade chips, email burr brown and ask them if they know any reputable suppliers that still have stock of this discontinued part. Or ask the supplier to show you the invoice from burr brown proving it's genuine. Then email burr brown and ask if it's a genuine invoice. Furthermore, if you don't have access to test equipment you won't know if you bought a genuine or fake anyway.

 

[GearMe]

FWIW...below you can see the 'K' on a close up shot from a Headfonia review of the Audio-GD Master 7

Also, when you google PCM1704K images most of them have K's on them

and...the seller has tremendous feedback numbers...plus there's the eBay money back guarantee if you're not satisfied

Seller information
shengmingelectronics (31447 )
99.7% Positive feedback


All that said, if you need test equipment to verify, then it sounds like you'll never really know for sure unless you have access to the proper equipment.

Besides, if the implementation is an important as everybody says it is, then will the chip version make a noticeable difference in the sound?



https://www.headfonia.com/the-flagship-audio-gd-pcm1704-based-ref-7-1/

 

[yildiray]

If you are really serious about buying genuine K grade chips, email burr brown and ask them if they know any reputable suppliers that still have stock of this discontinued part. Or ask the supplier to show you the invoice from burr brown proving it's genuine. Then email burr brown and ask if it's a genuine invoice. Furthermore, if you don't have access to test equipment you won't know if you bought a genuine or fake anyway.

Hi Erin,

Last time i asked to seller, do you have any reference customer who member of diyaudio/head-fi .com. They didn't give answer yet.I asked again for invoice today.I don't have test equipment to understand genuine or fake.So i try to search for references before buying chips.

 

[yildiray]

FWIW...below you can see the 'K' on a close up shot from a Headfonia review of the Audio-GD Master 7

Also, when you google PCM1704K images most of them have K's on them

and...the seller has tremendous feedback numbers...plus there's the eBay money back guarantee if you're not satisfied

Seller information
shengmingelectronics (31447 )
99.7% Positive feedback


All that said, if you need test equipment to verify, then it sounds like you'll never really know for sure unless you have access to the proper equipment.

Besides, if the implementation is an important as everybody says it is, then will the chip version make a noticeable difference in the sound?



https://www.headfonia.com/the-flagship-audio-gd-pcm1704-based-ref-7-1/

Yes i can compare chips which arrive to me with these images but i don't want to lost time if it turns out to be a fake.I hope i can find an advice from someone who buy genuine ones before.

 

[MojoAudio]

I agree with GearMe in that there are so many aspects of the application of a DAC chip that the specific "grade" is not particularly important.

FYI, companies like Burr-Brown don't set out to create a K version of a chip. But rather they make a production run of chips and measure them. The ones with the tightest tolerances (like most linear) are giving the highest grade ratings.

As a matter of fact, some of the connoisseurs of these vintage DAC ships will site out not just the better grades of a specific DAC chip, but which country and even which factory they were produced in. Over the years many of these same "number" and "grade" DAC chips were produced in Japan, Korea, and China. Being manufactured in different factories is part of the reason there are differences in the printing styles and wording on different DAC chips of the same "number" and "grade."

Note that the Japanese early production PCM1704 DAC chips are more highly prized than a K version of later Korean production.

Now lets look into the math on all of this...

You couldn't hear the four least significant bits on a so-called 24-bit DAC chip no matter what DAC it is in or what gear is in your system. Period. That's why recording companies never use those bits (they put in 0s for the LSBs).

Human ears can not hear the difference between a 20-bit and a 24-bit DAC, the recording companies never use the least significant bits on 24-bit commercial recordings (few even have 16-bits of resolution), and the noise floor in most DACs under $5K is so high most can't even resolve the least significant bits in a 16-bit recording. All sad but true.

In other words, all that "tight tolerance" stuff in inconsequential in most cases.

And that is not to mention the distortion you'll get from your digital source and the other components in your DAC.

Before upgrading a DAC chip to a K version I would recommend:

1. Upgrading the entire power supply in the DAC down to the individual regulators and caps at each chip.
2. Upgrading the op amps in the DAC so you could actually resolve the output from the existing DAC chips.
3. Upgrading anything else in the signal path, such as coupling caps, hook up wire, and connectors.
4. Add shielding and anti-resonant treatment to the DAC's chassis and individual ICs
5. Upgrade your digital source (transport or server). This is probably more important than any of the above.

Any and all of the above will make a more significant difference than the difference between the J and K versions of the PCM1704 DAC chips.

Actually, I would be willing to bet that it would make more of an improvement in the performance of most DACs to just do the shielding and anti-resonant treatment as opposed to any DAC chip upgrade.

And don't even get me started on tube output stages: there is so much noise in the power supplies and tubes in the output stage in most tube DACs that you couldn't hear the difference between the different grades of a DAC chip.