Theta Casa Nova vs Audio Prism Mantissa


Currently demoing these two preamps and having a very hard time on which one is better overall.  My set up is strictly 2 channel They both perform very well in my system with the following observations:

Casa Nova seems to squeeze every bit of detail out the recordings and then sum. Very good sound in two channel stereo mode. Voices and midrange is exceptionally good for a pre pro

Mantissa is like wise very detailed maybe one or two very small steps behind the Casa Nova. The Mantissa seems to be just slightly better than the Casa Nova in overall musical presentation maybe due to what I precive to be a wider soundstage or blacker background(if there is such a thing) the Mantissa is all factory original 

does anyone have experience with both or either of these units? Looking to get some opinions and thoughts from the community.
2channeljunkie
I had the Casanova, loved it.

Among it's best features was the incredibly flexible sub-woofer integration. If you are remotely interested in ever going that route, get the Casanova.

However, the manual may drive you nuts.

Best,


E
Also, the Casa Nova DAC is very nice, especially at 96kHz/24 bits.

With redbook it isn't as good as modern DAC's are, but absolutely enjoyable to listen to.

Best,

E
I LOVE seeing reference to the classic, overlooked, and largely forgotten AudioPrism Mantissa! I proudly owned and used one for over twenty years. I bought mine new from a prominent Columbus, OH high-end retailer who did not carry Audio Prism and who had never heard of it but was able to order one for me. The outboard power supply and dual mono circuit layout with dual stepped ladder resistor attenuators was classic. I had long conversations with it's designer Victor Tiscareno when it was new.-he could not have been nicer and more generous with his time over the phone to a complete stranger. It's nostalgic to me because the original duo of Victor Tiscareno and Byron Collet were only in business for 6-7 years between '92 and '98 or '99 when Mark Levinson took over the line of preamps and amps and rebadged them with slight modification as Red Rose Music. 
My Mantissa faithfully served me well with many hours of enjoyment, primarily with three amps-a McCormack DNA.5 given the 'Full Monty" upgrade by Steve McCormack, a DNA1 also heavily modded by SMcAudio, and an ARC VS110. Solid state or tubed, the Mantissa mated well. It is very easy on the four tubes-mine often went for three years of heavy use before needing to be replaced. Only a month ago, I replaced mine with an ARC Ref 6, a pre that cost 3-4 times more adjusted for inflation. The Ref 6 affords a more expansive soundstage and more detail, but the differences are largely in character as opposed to qualitative. The Mantissa was that good. Be sure to clean the rotary switch contacts at the rear of the pre with some isopropyl alcohol as they are prone to oxidation which affects SQ. I have zero knowledge about the other pre you mention, but the Mantissa is a great pre that is well built and reliable. 
Good question. I still have about two dozen pair of mixed 6922's and equivalents and 12AU7's and equivalents left over from the Mantissa and my advice is to use Upscale Audio, Jim McShane or Bob Hamme and simply ask them what they have at the moment that are good and reasonably priced. My experience with tube rolling in the Mantissa is that solid quiet tubes, particularly in the 6922's are far more important than any small character differences among current production and NOS. I splurged on some very expensive Amperex once and they were relatively noisy and not worth the price. The 12AU7's are cathode follower buffer tubes and have far less impact on SQ.  The Mantissa came with JAN Philips tubes-both for the 6922 and 12AU7 and IIRC they were among my favorites for overall clean, dynamic, uncolored sound. I recall having long discussions with Victor Tiscarino on the subject-he recommended I stick with the stock tubes but had no objection to tube rolling. This might be helpful to you; http://raptorelectronics.com/subpage3.html 
Thanks Fsonicsmith. I'm currently demoing both the Casa Nova and the Mantissa so opening her up and tube rolling isn't an option as I don't own the unit. Trying to settle on one of these two units? Any idea of what the fair market value on the Mantissa would be as I would need to consider this as well in making a final decision? 

Are you  in Columbus Ohio if so I'm in Columbus as well 


I am and my Mantissa which is in excellent condition is for sale. i have no idea as to current "fair marker value". My ARC dealer from whom I bought my Ref6 has it;  Brad at Sound and Vision in Powell. He was going to sell it for me. If interested, contact him. No reasonable offer will be refused. I no longer have the box or manual. I would throw in my collection of tubes if wanted.