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Recent upgrade to Cronus Magnum

A few weeks ago, my system consisted of the following components ...
Apple TV >> Naim Unitiqute (v1) >> Harbeth P3esr

While I liked the overall sound, I wanted to move up the chain and try something different. I felt the Unitiqute was a little underpowered. So when an Audio Rogue Cronus Magnum came up for sale (local craigslist), I jumped at the chance and bought it. I had a Cambridge Audio Azure 851D stored in my close, which I added to the chain. So now my system looks like this...
Node 2i >> CA Azure 851D >> Cronus Mangum >> Harbeth P3ers

When I first made the change, I was quite impressed with the increased loudness and a wider soundstage. However, I realized that, unlike the Naim, I was getting listener fatigue. There was a certain harshness (like metallic sound) to the vocals, especially female vocalists. Also, I was expecting some tube magic, which frankly is just not there. The Cronus Mangum sounds much closer to a solid state. Yesterday I put the Naim back in the system and much to my surprise the little box is keeping pace with the much more powerful Cronus Magnum. Yes, it doesn't play as loud and the soundstage is not as wide, but the sound is so much more refined, smooth and balanced. I'm wondering if I made a mistake. So before I make further changes, maybe the good folks at Audiogon can provide some relief.

What do you think is the weak link in my system? Should I keep the Cronus Magnum and try a more musical, refined DAC? If yes, what do you guys suggest (prefer used, below $2000)? Or do I ditch the Cronus and go for a more tube-like sound (Primaluna, Rogers, vintage ARC, etc)? The little voice inside me is telling me to sell the Cronus and move up the Naim integrated chain (e.g. Supernait), since I really liked the Unitiqute's refinement and balance. But then again, what if it's not the amp (Cronus) but the DAC (CA Azure 851D) that's the likely culprit here? Should I change the DAC first? Or maybe try rolling different (smoother?) tubes?

As you can see, I'm mighty confused and can use some pointers. So many variables ... aargh!!!!
128x128arafiq
twoleftears's avatar
twoleftears
5,318 posts
 
The center front tube, although only one tube, handles preamp duties for both channels, so on both counts it's the place to start.  I'd consider getting a couple of different options to roll in there rather than retubing the whole amp.  Andy Bouwman of Vintage Tube Services is another excellent source.
avanti1960
1,471 posts
 
the "whole amp" is really just (5) small signal tubes.  Leaving the JJs in is not going to get the best sound.  They are dark as to be opaque and unrefined.  
I spent 3 years perfecting the sound of the CM II with Harbeth speakers and tried many combinations of nearly every top NOS tube and the recipe works.  
Unfortunately Andy is not returning my calls or the calls of a friend either.  
phastrone
24 posts
 
+1 to all the posts in favor of the Cronus Magnum 2 with upgraded tubes. I liked mine best with a Brimar 12au7 from Upscale Audio in the center position and Sovtech 12ax7 lps in the ax7 positions. (I'm now using a Rogue Atlas for the bass drivers and a Rogue Stereo 90 for the top end with a similar tube complement.)
bigfishhk
10 posts
 
Don’t change all tubes at the same time, so start with say the 12ax7 and live with them for a while.
messing around with tubes can also be a rabbit hole. As an owner of several Rogue amps who,s rolled a lot of tubes in them, I am not sure going crazy with rolling tubes will be as productive as you think, but try in it stages and save money. Most of the new Rogue amps are not super tubey but shouldn’t be dry or harsh as u mention. I love the sound of my 99 pre amp with stereo 100. I also recommend Andy at Vintage TS so long as he answers the phone! Good luck.

jvancamp78's avatar
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jvancamp78
5 posts
 
I too had a similar experience with the Rogue Cronus Magnum ii. I am, by no means, an expert and I am only relaying my impressions. This was probably 5 yeas ago and the Cronus was my third step of upgrades with tube gear and I was really let down by its lack of “tube sound”. I now have all separate tube gear in my analog chain (phono preamp, line preamp and SET monoblock power amps. Ironically, I too have the same Cambridge Audio Azur that I use only as my DAC while streaming).

I am surprised no one has mentioned what I consider to be the single greatest factor to why the Cronus lacks what I call the tube sound. This being that it has solid state rectification. I know that some people actually like this and Rogue markets it as one of the benefits in some of their models. All of the pieces in my current chain have tube rectification. To me this has been the real key to getting more tube sound. I have had two experiences with tube gear that use a solid state rectifier, the Cronus and the Cary Audio SLI-80HS*. Both the Rogue and the Cary lacked the warmth and space I was seeking. And, like a few have mentioned here, I went down the rabbit hole with both the Cary and the Rogue trying countless NOS tube combinations and spending gobs of money. Fortunately, I have been able to use some of those tubes, with great results, in subsequent tube gear. Also, I have had a couple Cary pieces since this one that use tube rectification and have loved them (including my current phono preamp, the Cary PH302-MKII).

Again, this is personal preference and many people actually prefer what the combo of solid state rectification and tubes offer. Just not me. I want tubes to sound like tubes.

Hope this helps.

Jared

*interestingly enough, I read about a year ago that Rogue was suing Cary over the use of solid state rectification in tube amplifiers claiming they stole a design. Haven’t heard whether or not it was settled.
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