Class D is just Dandy!

I'll second tsugury's recommendation of the Rogue Sphinx.  I've had one in my system for a couple of years now and continue to be impressed with its performance, especially considering its very modest cost.  I hesitated considering this amp, as I've previously found Class D amps to be somewhat sterile sounding and fatiguing over time.  Not Rogue amps.  I believe that this can be attributed somewhat to modern Class D modules, but also to Rogue's tube preamp section and their use of a beefy linear power supply.  Quite musical and dynamic!

Hi riskymichael,

     I've never had the pleasure of listening to the Rogue Sphinx integrated amp but find it very interesting because of its combination of a tube preamp section with a class D amplifier section.that uses a traditional toroidal power supply rather than a smps (switch mode power supply) like typical class D amps.
     As many class D amp users, including myself, have already stated earlier on this thread, the combination of tube preamps with class D amps has resulted in exceptionally good system performance with a broad range of both tube preamps and D amps.  I can attest to very good results pairing a VTL 2.5L (the standard Chinese tubes being rolled to a set of NOS Mullard tubes) with my first class D amp, a Class D Audio SDS-440-CS that was my main amp for a few years and also has a toroidal power supply. 
     Obviously, Rogue is well aware of this synergy of tube preamps with class D amps and it's likely a major reason why your Sphinx sounds so good.
  
     The subject of whether there's a performance benefit to using the more traditional toroidal power supplies rather than the newer switching ones in class  D amps is less clear.  I now use 3 class D amps in my combo 2-ch and ht system, 2 stereo amps with toroidal power supplies and a pair of mono-blocks with the newer switch mode power supplies.  I notice all have the usual class D attributes of very low background noise, low distortion, high detail levels from top to bottom, very good dynamics and being very accurate and neutral overall. 
      The mono-blocks are more expensive,use different class D power modules and are much more powerful than both stereo amps.  I do notice the monos are even more detailed, even smoother and more life-like in the mid-range/treble and portray a more solid and stable soundstage illusion which I attribute mainly to the different class D power modules.  I also notice the monos have more powerful dynamics, especially on better 24/96Khz files recorded direct to digital, which I mainly attribute to the significant increase in power and perhaps the power modules and smps, too. 
      However, I'm unwilling and unable to claim whether the difference in power modules or power supplies are responsible for the clear improvement in dynamic range of my mono-blocks. 
     Without comparing otherwise identical versions of our amps, one version with a toroidal and the other with a switch mode power supply,  I don't think we can determine which performs best. But even this comparison would not address the relative degree that the power modules and power supplies affect amp performance.  
     The only things I can state with certainty is that my smps monos are more efficient and run cooler than my toroidal stereo amps. 
 
 Tim

@scott_w 
I have a pair of Cherry Amp 60V King Marischinos. Prior to, I auditioned Merrill Audio's Taranis; I ordered the Cherries afterwards. I was impressed with both. Both needed about 4 hrs of music before sounding good. Honestly I find all stereo gear need varying amounts of time to break-in. Which model did you get and what are your impressions?

Tim,
    Thanks for your thoughts on my post.  Your observations on switch-mode vs linear power supplies were especially interesting.  I know that, historically, switch-mode supplies were often prone to generating high frequency noise.  With that knowledge in the back of my mind, I always attributed at least some of the fatiguing sound of earlier Class D amps to that aspect of the design.  Call it a hunch.  :)  Perhaps more recent designs have resolved this issue.  It would be enlightening to hear the same amp with both types of power supplies, but that obviously is not logistically very easy.  I think I'll be connecting with the very pleasant & helpful folks at Rogue to ask them if they had ever used a switch-mode power supply in the Sphinx (or its bigger brother, the Pharaoh) during the design process and why they ended up with a linear supply... 
     As far as the tube preamp section goes, I think that its positive affect on the overall sound is pretty much indisputable.  I also have tube rolled with my Sphinx and it has significantly changed the character of the sound.  The JJ 12AU7 stock tubes supplied by Rogue were more than adequate.  However, I finally ended up with a pair of Psvane tubes.  They provide quite a bit more "air", as well as much more holographic "fleshed out" images.  Gotta love it.
     Cheers - Michael

@mdeblanc I bought the basic cherry amp. I just updated my system info today w/pics etc. Had a couple blokes over yesterday for a 2 hour jam, the prior prez of the Boise Audio Club (who also has his eye on PMC) + the bloke who intro'd me to Cherry when he brought his over a month back. Thumbs up all around from them. The rig is singing.