Before I answer, a little disclaimer, I never used Modi or Creative X7 before.
Yes it is true. As the name suggest, the fixed output will output the signal at line level at all times.
Yes it is true, but for this price range, I wouldn’t worry about it for too much because there are other factors that are more important and more affecting than the variable volume control.
So, if I want to be pedantic about it, every additional stage or process to the signal will affect the signal in one way or the other. In DAC at this price range, most likely the resistors or the system that they use for the preamp stage is not that good. From my own experience, the low quality resistors that they use in this price range does impact the sound in a negative way, but again, I would only notice this when I’m having a critical listening session. If you want an absolute performance, then you can consider having a preamplifier in your system, but IMO it’s better to put your preamp money to a better DAC.
But when you connect any DAC through USB to a PC, there is a digital volume control in windows that can be increased or decreased…Creative X7’s volume knob is digital. Turning the knob would increase/decrease the digital volume in Windows. Does this mean that X7’s DAC does not have a preamp ?
Some DACs come with a potentiometer on them, and do not control the volume digitally. The volume control is analog… these are the DACs that have a preamp, right ?
Most DACs (there are exceptions) have some kind of output stage (Buffer, Op-Amp, Discrete Circuit, etc.). Does not matter if there is a pre-amp section built in or not.
Depends. There are good and bad designs and good and bad components.
In theory, one could make an output stage with a lower noise floor than the DAC before it.
I am not familiar with the APIs and Soundstack in Windows (or the X7) to give a qualified answer.
It might be possible to get the full bit-depth from Windows and then attenuate/boot volume after the Digital to Analog conversion.
It is possible to have digitally controlled “analog” volume control (Digi-Pot, voltage controlled amplifier, etc.)
But in general, a volume pot is a good indication of a pre-amp section being present in the DAC.
Absolutely. DACs have come a long way since the X7 was released and the hardware was more about the unique combination of features than any outstanding qualities.
IMO, the X7 is a pyramid of steaming shit because Creative couldn’t/wouldn’t fix the firmware/software. Common story with Creative products and a big part of why I’m still annoyed I bought an X7 after knowing better from previous experiences.
It depends on the implementation, can’t make a generalized statement on it.