I know this may not be a popular opinion but essentially all pre-amps will sound the same if they are doing their job well. They are supposed to simply transmit sound and not modify (with the exception of DSP modes)it in any way. So I would say, the differentiating factor would be the features and build quality. If you have no need for the features I would highly doubt you would be able to hear a sound difference between the 950 and 990 and any other pre-amp in an A/B comparison. It could be feasible that one would be more electronically perfect than the other but if the variances are below human hearing who cares?? Modern electronics have such a low noise floor, and virtually linear frequency response that nowadays our focus should be on the real things that cause huge differences in sound: your speakers and your listening room. Dont get me wrong, I love the 990 but if they were both still on sale I would get the 950 since I dont need the 990 feature set. And I am sure they would both sound JUST AS GOOD.

Why buy something as expensive as the 990 if they all sound the same? Unless build quality is the utmost important thing for you when it comes to buying electronics.

Good comments, gentlemen.
I wonder if the chips for (DOLBY D, DOLBYEX, DTS, DTS-ES, NEO:6C/M) are the same in 950 to 990?
I had tried to compare the spacs from both manuals, but don't have a clue.

Well the truth is the 990 is not "Expensive" when compared to other pre-amps. As a matter of fact I think it is the least expensive retail price on the market for a pre-amp. In addition it has very expensive options like digital video switching, balanced outputs, automatic configuration, etc. that are usually found in 3k preamps. So in my humble opinion, buying a 990 would show that you don't believe in "magic unknown technology" when it comes to electronics and their is no voodoo magic a Krell Pre-Amp can do to sound that an Outlaw can not. Especially when they are designed to do NOTHING to the sound! If a 990 is out of budget than a used 950 or forgetting seperates and getting a receiver would be more affordable options that would again SOUND JUST AS GOOD.

Elikd: I hear you. I have the 950 and today is the deadline date to order the 990. I have a high end parasound DAC for stereo music, which is superior to the DAC in 950. So i am not quite concern much about the Stereo By-pass in 950 or 990 (after all they are AV processors).

That's why I keep asking owers of 950/990 for inputs before submitting the order today. Tough decision.

Elikd, I assume you are just talking about the digital side of the preamp and not the analog right?

Kwok, you will only be out $60 bucks or so in shipping to try it out. Forget my opinion or anybody elses, only you can judge.

Jed M: Tks.

Kwok

Digital or Analog. Let me be clear on one thing though, I am assuming that what sounds good also has good measurements. There are actually many extremely high end components that ADD distortion to get a certain sound (Tube Amps do this). The audiophile likes this sound and then claimes it to be "Better". I believe that components should be tranparent and any colorization should come from the recording engineer. If we assume that by good sound we mean it will also have excellent measurements than you can apply the following rule to electronic components:

Elecronic componentes will be audibly indistinguishable if they have:

1- Flat Frequency Response
2- Noise and Distortion levels below audible thresholds
3- High Input impedance and low output impedance

Now this is the engineering/scientific and measurable point of view. Many people claim to hear things that are NOT measurable or claim that non measurable things still affect the things we can hear or that "Good" sound does not measure as such. Thats where we go off into exotic audiophile land with $1000 speaker cable, CD rings, and wierd amp, pre-amp designs, etc.

Then I guess we will just have to agree to disagree. Theoretically you may be right about analog, but in the real world there is no way I can agree with you that all analog sounds similar to one another, even in similarly priced gear.

elikd - First off let me say I don't necessarily disagree with what you are saying. I do think there is an art to Analog PreAmp design that very well may be audible. Maybe not to you or me but I would not be so quick to dismiss it. As you said a tube Pre actually colors the sound. I believe the "Art" of analog PreAmp design, even solid state ones can have different electrical and sonic characteristics. Who knows if it is audible? Do you really believe all reasonably designed PreAmps have the same:
1- Flat Frequency Response
2- Noise and Distortion levels below audible thresholds
3- High Input impedance and low output impedance?

If not, I don't believe it is fair to say they are all going to sound the same. Just to be clear I'm talking about just the analog PreAmp section not the digital PROcessing. I disagree that the function of a PreAmp "is to simply transmit sound and not modify", it does condition the signal that is the function of a PreAmp. As I am a big user of the bypass modes I'd be very interested in comparing those modes between the 950 and 990 and can very well believe there may be an audible difference between the two.