MSB Link DAC III vs. CAL Sigma

I'm seeking opinions on which DAC would best suit my system, the CAL Sigma with a Telefunken 12AX7 tube installed or a stock (unmodified) MSB Link DAC III. My system currently consists of an Audible Illusions Modulus 3 preamp, Golden Tube SE-100 power amp, Pioneer Elite PD-54 stable platter CD player that I'll be using for the transport, and a pair of Acoustat Spectra 11 hybrid electrostatic speakers. I'd have to say that presently, the one biggest problem with my system is that it tends to sound a bit dark. So, how about it? Which DAC would you recommend to put a little more life into my system? Thanks in advance for any recommendations.
the msb will have stronger more defined bass control and a more'neutral' sound overall; the cal will be mellower and have a nice bass body and roundness to it with the Telefunken.
I have a 24/96 Sigma and the Telefunken is a good tube with it.
The power base with the MSB will improve the sound overall, for an extra $____?
I think the darkness is from the Golden tube amp mated with the speakers. Try a Pass Aleph 30 and the darkness will go away!
But then you might miss the 'midrange magic'!
this is a frustrating hobby at just can't have it all!
The MSB in stock form is definitely brighter sounding whereas the CAL sounds noticeably "tubey" i.e. warm and romantic. Since you already appear to be on that side of the spectrum, the MSB might be a better choice. It will add a somewhat transistor sound to your system, but this can be worked out with relatively inexpensive mods. Sean
If you want to "lighten" the sound of your system without ruining it, you may want to try some "revealing" cables. If you do not have a good local dealer to work with, try the Cable Co, as you should "try before you buy" and they usually can recommend something that will work with your gear. For Dacs, I have tried a stock MSB Link I at home and also owned a Cal Sigma. I would vote for the Cal Sigma. I did not consider the Cal to be as mellow as some do (neutral would be my opinion of it). However, I did think the MSB was lean sounding.
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Joe B and Jab, where you using the earlier Sigma or the 24 / 96 Sigma II ? I think that there is a BIG difference in sound between those two. Sean
I was using a Sigma II, but it was not the 24/96 version. I only tried the stock Chinese tube and a Sovtek, and preferred the sound of the Sovtek. I did not consider the Sigma II to be harsh sounding and I would have lived with it longer, but I already owned a Micromega DUO BS2. Here is where my personal taste or bias comes into play. The Micromega admittedly had less inner detail and a smaller soundstage than the Cal. Initially I found the Cal exciting, but when I switched back I found the Micromega reproduced the sound of acoustic instruments more realistically and was more enjoyable to listen to on a long term basis. I did not recommend the Micromega above because Mike said he was looking for a lighter sound.
Just to make it clear for all of you who are kind enough to respond to my question, the CAL Sigma is the original version, not the Sigma II and, as I said, the MSB is the basic, unmodified Link DAC III. Thanks for the information so far. Keep it coming. Mike
Well, the great debate between the CAL Sigma and MSB Link DAC III is over. After extensive listening sessions, particularly ones using classical music rather than my usual preferred soft jazz, the MSB is the winner, hands down. I regretfully have to admit that when I read the comments of "jab" saying that the Sigma with the Telefunken tube didn't sound at all like a tube DAC, I dismissed this out of hand. After all, how could it possibly be that a DAC the quality of the Sigma combined with what many have called the best sounding 12AX7 tube available not sound extraordinary?? But, "jab" was right. The Sigma, especially with full orchestral pieces and massed strings, was downright harsh and brittle sounding. Apparently, the top shelf reputation of the Telefunken 12AX7 stems from it's performance when used in preamplifiers. And, "Tacs" was also spot on in his assessment when he said that the bass of the MSB would be stronger and better defined. Fact is, the MSB really outdid the CAL in every respect. The MSB's bass is much deeper and better defined, it is far more dynamic and handles transients substantially better, stringed instruments and piano have considerably more body, and with the MSB I could clearly delineate individual instruments in passages with massed strings. I want to thank all of you for your input and excellent advice. Mike Ballinger
Thanks for the update Mike. It just goes to show how system and personal taste dependent these things can be. I also think that the "mystery" of production tolerances from unit to unit can come into play.

I have two Sigma's ( one earlier version, one 24 / 96 ) and two Alpha's ( both earlier non 24 / 96 versions ) along with a few other DAC's. If i had to pick one of these DAC's as sounding the warmest, smoothest and most "romantic", it would be the early Sigma hands down. This is with the stock tube too, even though i've tried other tubes in all of the DAC's. It does not have the top end resolution or spaciousness of some of the other DAC's, but it is pretty phenomenal on female vocals, jazz and acoustic based music.

This was the first tube based DAC that i had bought and it opened my ears up to the "musicality" aspect of digital. Before that, it had always sounded "soul-less" and sterile. As you can see, i found that specific unit impressive enough to venture further into their product line to check things out. Needless to say, they all sound slightly different : )

Either way, it's good that you found something that suits both your tastes and your system at a reasonable price. Sean