Dissatisfied with digital audio

By stand alone DAC I mean a unit that is only a DAC vs DAC & preamp like the TubeMagic series. I tried a Chord Mojo in a local store a little while ago and the difference with headphones was remarkable. Assuming price is proportional to quality, the Mojo is a better DAC but does the extra power from the Mojo's amp have more of impact on the quality of output?
 
These two functions together, plus the power supply, make up what is commonly referred to as a DAC.

I've referred to it as an 'ensemble DAC' elsewhere, to distinguish it from the DAC chip itself:

As mentioned by others, besides the actual DAC chip, the other factors determining the quality of an 'ensemble DAC' device (as opposed to the chip) are analogue output filtering & buffering, power supplies & decoupling, clocking, and PCB layout (to prevent coupling of noise between digital & analogue sections). In no particular order...

Engineering is about compromise; it depends what we're compromising on. Mostly price. Price determines how much care you can take with all those aspects of the ensemble DAC.
 
By stand alone DAC I mean a unit that is only a DAC vs DAC & preamp like the TubeMagic series. I tried a Chord Mojo in a local store a little while ago and the difference with headphones was remarkable. Assuming price is proportional to quality, the Mojo is a better DAC but does the extra power from the Mojo's amp have more of impact on the quality of output?

What would be an example of a unit that is a DAC only? That is, without amplification?
 
What would be an example of a unit that is a DAC only? That is, without amplification?

I didn't realize that all DACs also amplified the analog signal. With headphones, using the Mojo vs the DAC in my digital player was a huge difference but it that a function of the chipset or the amplifier in the Mojo?
 
One, the other, or other variables (such as outlined by cpt_paranoia).

You will see that opamp "rolling" is not uncommon in the DAC world, with the intent of changing the sound qualities of the unit.
 
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I didn't realize that all DACs also amplified the analog signal.

They will have a buffer amplifier. This may be integrated within the DAC chip, or it may be implemented using one or more op-amps in addition to the DAC chip. These op-amps are also commonly used to implement the output reconstruction/anti-aliasing/anti-imaging filter that is required to remove the sinc image/alias at Fs, created by the DAC's inherent zero-order hold (output sample) function.
 
but it that a function of the chipset or the amplifier in the Mojo?

Further to my post above, here are some other things that determine the quality of a DAC:

Switching supply where appropriate (for the digits), and low-dropout, low noise, linear PSU where appropriate (for the analogue). Multiple linear supplies where necessary in the analogue, for instance, the DAC clock will have its own supply. But this has to be part of a well-designed power supply and system design, with appropriate isolation between the various stages of the processing (e.g. network interface, digital rendering engine, DAC digital interface, DAC clock, [DAC reference voltage], DAC analogue output, analogue filtering & amplification). I really don't care too much about the first two. I start to take care with the DAC digital interface onwards. That applies whether I'm designing analogue audio, video or RF circuits.
 
Ignorance is bliss.;)

Conversion occurs in the D to A circuit, implemented in the DAC chipset.

But there is also an analog amplification stage in the same box, generally implemented via an opamp IC, but in some more exotic units via discrete components.

These two functions together, plus the power supply, make up what is commonly referred to as a DAC.

So, while the conversion function alone can be referred to as a DAC, in a thread such as this the term applies to the full device (conversion, amplification, power supply).

That's one way to look at it. That's one way to define it. I'm sure we all appreciate the lesson.
 
That's one way to look at it. That's one way to define it. I'm sure we all appreciate the lesson.

Within the context of this thread, and the context of home audio gear, what would be the other ways? The performance of the OP's "DAC", and all other turnkey DAC devices, is certainly based on all of its functions, not just its d/a chipset.
 
Within the context of this thread, and the context of home audio gear, what would be the other ways? The performance of the OP's "DAC", and all other turnkey DAC devices, is certainly based on all of its functions, not just its d/a chipset.

The question asked, in the context of digital v. analog, was whether a tube DAC would somehow fix a problem that a solid state DAC would not, implying that tubes or transistors somehow cause DACs to behave differently, and I pointed out that tubes and transistors have nothing to do the conversion from digital to analog
 
I have found a notable variance in the sound qualities of various DACs. This variance can be a function of the D/A chipset, the analog stage, the power supply, etc, or a combination thereof. Therefore, a tube in the analog stage - or any variety of other design differences in the functions that make up what is generally referred to as a DAC - can change how the DAC sounds. It would be up to the OP to determine if the the sound of a different DAC is an improvement or not, but I am convinced that there is certainly a variance from one design to another.

Therefore, since the OP's "problem" is that he is not as satisfied with the sound of his digital system as he is with the sound of his analog system, it seems obvious that a different DAC has the potential for addressing his problem. Of course, it could be any number of other variables as well (speakers, room, power amp, etc).

But let's focus on the DAC....the little Topping amp is nice for the price (I bought one last year for my daughter so she could listen to music from her computer through her Nakamichi TA4A receiver and AR6 speakers), but it paled in comparison to my MF M1, or even my Maverick D2. It's sound, to my ears anyway, is on the thin side and lacks the fullness/musicality of its higher end competitors.
 
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I have found a notable variance in the sound qualities of various DACs. This variance can be a function of the D/A chipset, the analog stage, the power supply, etc, or a combination thereof. Therefore, a tube in the analog stage - or any variety of other design differences in the functions that make up what is generally referred to as a DAC - can change how the DAC sounds. It would be up to the OP to determine if the the sound of a different DAC is an improvement or not, but I am convinced that there is certainly a variance from one design to another.

You and I are in complete agreement. We were simply defining DAC differently. You, broadly, me narrowly.
 
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What would you suggest the industry adopt as the correct term for what they, and most all users, have long referred to as DACs? Integrated digital to analog converter amplifier boxes?
 
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Just as in the days of the past. Digital can run the gamut from excellent to blah, to just plain ugly. Its not the formats fault its the people who engineer and produce the recordings. Its just like LP's. Most have very little bass below 50 hz, be it accurate or not. Try to find a LP with accurate bass down to and below 30 HZ. Its not impossible just very rare. Listen to the high end, it varies from label to label and artist to artist and from one producer to the next. Listen to the difference between Frank S. on Capitol verses Verve. Though Franks voice isn't as strong as it once was the Verve recordings have a magnitude less distortion, great highs and don't have that hard upper midrange sound. Listen to Deutsche Gramophone recordings versus Sheffield, Telarc, Reference recordings, they are night and day. difference. Its like DG is stuck in the past. They didn't put bass on their LP's and most of their CD's fail, too. Since Sony took over Columbia its been a mixed bag, better to much better, but yet still not right. I like Chndos recordings, though I admit sometimes their recordings are to distant with too much room reverberence . A lot of recordings both in the past and today are miked much to close to the performer. Especially small jazz groups and a lot of Classical quartets etc. Soloists sound like they are in your living room rather than in a nice concert venue.

Its not all about tonality either it can also be about since of space and depth. You can't blame a format if the presentation sounds like it was coming from the bottom of a well or with a mic placed down the Sopranos throat. Neither format can tolerate those choices. Then there is the performance itself. Musicians can usually hear thru the recording mistakes to enjoy and critique a performance. Audiophiles get so hung up in the sound quality they can't recognize the quality of the performance some of the time. Its a shame because there are quite a few performances that are quite spectacular covered up by a rather poor recording technique. It would be fun to go back to the 60's and remake all those remotes digitally using modern mixers and microphones, to hear the differences I made so long ago.. Imagine no tape hiss, extended smooth bass below 35 hz, and clean clear undistorted High frequencies. But no matter the technology differences, its the performer, the space in which the performance took place and the the artistry of the person capturing the sound to get the best compromise to be delivered to our ears.

You just can't compare two different formats using two different sound systems in two different spaces. A+B+C does not equal D+E+F......
 
I didn't realize that all DACs also amplified the analog signal.
It is no different that recognizing that a phono preamp serves initially to provide the inverse RIAA equalization - then it must amplify the signal to that of a "high level" source a preamplifier can use - typically 2V. A DAC is no more than a CD player without the optical transport.

My experience is that the quality of the power supply and output stage (as with any audio component) make a bigger audible difference than merely the DAC chip implemented. I recently improved the transparency of the DAC I use in the garage by replacing the TI op amps with Burson FET modules.
 
The DACs are so close in specs today. The leaders IMHO are the non off the shelf DACs with superior clocks for timing. Look at PS Audio's Directstream DAC, or Chord's lineup. FPGA is the future. And Paul from PS Audio said it's not about specs, it's about how it sounds. My $0.02 guys.
 
Not really, old tech really. The problem with FPGA, just like BIOS chips, is they are prone to static and other issues as well as how long will they are supported. If they drop the DAC and no longer support it, what good is an FPGA DAC if you can't upgrade it or have a bug that was never patched.
You should do some more homework. The FPGA is very upgradable.

"DACs come in several basic types. First, there are “chip DACs” that use a modern digital chip made by AKM or Burr-Brown as the heart of their designs. Second are “ladder DACs” which use a resistor array to decode a digital signal. These are usually expensive due to the high number of critically-matched parts needed to make the design successful. MSB and dCS are two manufacturers who make ladder-based DACs. The third kind of DAC is an NOS (short for “non-over-sampling” but this could also stand for “new old stock”) DAC. These use older DAC chips with “simpler” internal designs and filters that some audiophiles prefer due to their relative simplicity. Finally, we have FPGA DACs, which use a field-programmable gate array chip as their heart. The FPGA can be thought of as a blank slate that can be programmed to perform any function. PS Audio’s DSD and DSD Jr. and all Chord DACs use this last methodology."

"Compared with other DAC designs an FPGA-based DAC has several unique characteristics, the most important being the amount of custom programming and proprietary algorithms that can be applied to a design. Over-sampling, digital filters, and the way the DAC works on a very basic level all can be dictated by the firmware in the FPGA. Also, an FPGA DAC can be updated incrementally, or have its operating system completely changed by a firmware update."
 
The FPGA is very upgradable.

He didn't say FPGAs aren't upgradeable; he specifically referred to the manufacturer ceasing support for their FPGA-based DAC.

If the manufacturer stops producing upgrades, you won't be able to upgrade the FPGA firmware, unless you have access to the source code, have the build environment, and have the relevant skills.

As it happens, I do have those relevant skills, including the ability to create my own source code design from scratch, but even I probably wouldn't bother...
 
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