Plinius SA102 (vs Rotel RB1090)

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Joey_V

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The Plinius SA102 has arrived as most of you probably know by now and I am obligated to write a review about it and referenced to my previous reference amplifier, the Rotel RB1090 dual monoblock amp.

Setup:
SqueezeBox 3 -> Rotel RC1070 preamplifier -> Rotel RB1090 amp/Plinius SA102 amp -> Martin Logan Summits -> Joey's ears

Build:
Both amps appear to be well built, but the Plinius is better overall. The thick aluminum faceplate, the large handles up front, the massive ivy-like heatsinks along the sides. The Plinius just oozes quality! I know this probably has nothing to do with the sound, but if you knock on the Plinius, it doesnt have that hollow, thin-gauge feel of the Rotel. You can sit on the Plinius and not dent the top cover, but if you sit on the 1090, you may lose some resale value on audiogon!

Even looking at pics of the internals show how superior the Plinius is. The Rotel 1090 is a nest of wires and cheapy looking resistors and transistors while the Plinius appears to be well thought out throughout. Not to mention, the components Plinius use are a step above the Balanced Concept of the Rotel 1090 (whereby they use good components only in certain parts of the amp so as to lower retail price and costs). For example, Plinius uses Silver wiring in the internals.

SA102-SIT.jpg

SA102-SIB.jpg

vs
rb1090.jpg

rb1090no1.jpg


Sound:
The difference was apparent from the getgo. I didnt even need to do more than ONE A/B comparison between the 2 amps. I used 4 songs that I knew very very well and I stuck with those to simplify the comparison. The first song is a FLAC lossless of "Pennies from Heaven". Louis Prima, the singer, is clearer and without fuzz through the Plinius. A stark difference from the slightly overly "airy" Louis Prima through the Rotel 1090. The biggest difference I noticed was what I have coined: "Vocal Focus"

The Plinius has an uncanny ability to take the Louis, push him forward a bit on the stage, pull the drums and snares a bit further back, and take that wonderful yet raspy voice and remove as much fuzz as presently possible (note that I am only using the Rotel RC1070 preamp here). With the Rotel, I noticed that there was quite a bit of fuzz around Louis' voice... it wasnt a "good type of airy", but more of a depiction of the 1090's inability to grab the panels as well as the Plinius did. As a result, the Plinius trounces the Rotel in Vocal Focus and brings together a more pinpoint vocal image relative to the 1090.

The second song is "Baby It's Cold Outside" by Leon Redbone and Zooey Deschanel. The two singers sing side by side in this song... and it's been a little iffy for me as to who sings where.... ? Does the guy sing to the left of the girl or vice versa? With the Rotel, I could sort of make it out, as to who is where... but when I switched to the Plinius, it was very VERY apparent who was singing where. The vocal focus was amazing and the blackness between notes (in this case, vocalists) was impeccable! I could EASILY EASILY EASILY tell that the woman is on the left and the man is on the right! It was simply amazing how much clearer the Plinius is.

The third and fourth songs were James Blunt's "You're Beautiful" and "Goodbye My Lover". Both songs are among my favorites as it displays mostly his vocals and doesnt muddy it up with too many unnecessary instruments. In both recordings, I noticed that the Plinius took the vocal image and gave it a FUZZ-FREE vocal focus. Love it! The Rotel 1090 had residual fuzz around the vocal focus and this took away from the realism of Blunt's rather unique voice.

Relatively speaking....
I came from a Rotel RB1070 and I remember asking the people on this forum how to improve the vocal focus and the vocal imaging. I even remember posting as to whether vocal imaging was a weakness of electrostats as I once thought they were prone to providing a rather larger-than-life vocal image.

I questioned my amp, but I didnt seem to get much support with that idea. I eventually upgraded to the Rotel RB1090 and was pleased with the results. The vocal image was definitely improved and the vocal focus had lesser fuzz. Also, the 1090 had made a more believable 3D plane as the singer's voice was brought forward outside the speaker plane and the stage was brought back a bit. The 1090 trounced the 1070, hands down.

YET, I think that what the Plinius brings to the table relative to the 1090 is a larger jump than the jump I experienced between the 1070 to 1090. The Rotel 1090 to the Plinius SA102 is a more significant leap towards audio nirvana! Hard to believe? Well, believe it! Whoever said the Law of Diminishing Returns started at the $2K retail mark was wrong. The jump is that significant, that pleasing, that involving, that much more SATISFYING!

Sound, other than the Vocalist
Overall, the Plinius brings clarity and more weight to all other instruments. The guitar feels more real, the trumpets blare with more gusto, the violin is a bit more refined, the snare has a bit more bite. Basically, there is more LIFE in the reproduced arts with the Plinius relative to the Rotel 1090. Dont get me wrong, the 1090 is still wonderful, but the Plinius offers just as much power, current, and transient capability as the Rotel 1090 but adds LIFE to the recording!

I will add, that in the song "Pennies From Heaven", I noticed a deeper soundstage.... as cliche as that sounds. I feel that it's due to the clarity and body of the instruments that lends this feeling of a deeper stage, as if I could almost walk to the back by the snares. Eerie... I know!

Does Class A actually work?
This was one question I wanted addressed from the beginning. Does it work? Does all the mumbo jumbo about continuous power, current, and a non-fluctuating voltage rail of Class A bias actually make a difference in sound? In my experience....

YES. There is a significant difference in quality when the Plinius is biased to Class A vs AB. I had my brother man the bias switch as I listened intently for any differences. As usual, I focused mostly on the vocal image and the vocal focus. In Class AB, the Plinius sounded a little more like the 1090. I heard FUZZ around the vocal focus, it just wasnt as refined. Switch over to Class A and in a seconds, I noticed the vocal focus begin to SHED away the FUZZ and the vocal image was noticeably pushed a bit more forward on the stage. Switching back and forth convinced me of this phenomenon and was further evidence of the differences between Class A and Class AB with regards to the Plinius SA102.

When critically listening, there is no substitute for Class A bias.

Conclusion
The Plinius SA102 is truly world-class! I just love how this thing oozes quality and how lucky I am to have stumbled onto this particular one. I would like to thank Papa Dave (aka Twich to the rest of you) for pointing me towards this particular audiogon ad... which turned out to be a stunner ($2500 + shipping/paypal for an Authorized Dealer's 1 year old store demo unit with FULL 7 year warranty). Thanks Papa Dave!

Thoughts....
Overall, this upgrade has taught me that there is such a thing as HI-FI. There truly is! I was beginning to think that it was mumbo jumbo past a certain price point, but this Plinius has taught me otherwise... atleast up to the $5-6K price class.

It has also taught me of the imporance of the electronics as it can make or break your system. A system with a good foundation is necessary for any speaker to sound to its potential. This realization has made it difficult for me to truly assess speakers when auditioning at shops as each component beyond the speaker chain has an influence on that particular speakers' sound that may color your judgement either for the better or for the worse.

Lastly, it has taught me about the importance of Class A. I have experienced Class A before, with a $750 headphone amp. The headphone amp did EXACTLY the same thing for the headphone sound as the Plinius SA102 did for the speaker sound. The same "REMOVAL of the FUZZ" was experienced on both occassions and I have no doubt this is the result of the Class A topology. I believe, at the moment, that Class A is the way to go for SS amplification.

Thank you all... and I'm getting off my soapbox.
 
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Excellent Review!

Joey,

What and excellent review and comparison of the Rotel 1090 and the Plinius SA102. Joey you've out done your self... :D

Well done Joey... :D
 
Very interesting stuff! I look forward to hearing what you have to say as time passes. I'm sure even more detail will pop out at you. ;)

P.S. "Nests" of wires aren't necessarily a bad thing. Point-to-point wiring aleviates the use of circuit boards in many amplifiers out there...... and some schools of thought believe that circuits can be a bottleneck in audio. :)
 
Joey, glad to hear your intial listening has proven to be sooooo good ! Also just as glad that the Audiogon deal worked to your satisfaction. Also "Papa Dave" has to pass on some of the credit to Dan aka DTB300 for it was several of our late nite conversations that prompted me this past winter to locate my SA-102.

I think after you have had a chance to get really comfortable with your new set-up (once you have integrated the mystery pre-amp) you will become even more envolved in the presentation of your system and how well the music is reproduced ! Yeah...... we have the makings of a "cult" thing here !!!
 
What's the difference between the SA102 and the SA100? Thanks!
 
What's the difference between the SA102 and the SA100? Thanks!


main difference is better AC integration to power supply/transformer, seems there were some mech. noise issues with the SA-100, folks down in New Zealand are 220-240 volts, so I guess that was the excuse. There may have been some other minor tweeks but that is the one given to me buy their importer / distributor in Ca.
 
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main difference is better AC integration to power supply/transformer, seems there were some mech. noise issues with the SA-100, folks down in New Zealand are 220-240 volts, so I guess that was the excuss. There may have been some other minor tweeks but that is the one given to me buy their importer / distributor in Ca.

As Dave said, the big difference is in the PS (toroids, etc)... which is why I held out for the 102. ;)
 
Dave, Joey -- thanks for your replies. The reason I asked is that there was a 100 that popped up nearby. I managed to close my eyes long enough!
 
As Dave said, the big difference is in the PS (toroids, etc)... which is why I held out for the 102. ;)

Joey,

What is retail on the Plinius SA102? I don't disagree with your review in anyway, but I doubt it is really a fair comparison to put the SA102 up against the RB1090. I can't imagine someone cross shopping those, but I guess anything is possible. In the used market it looks like the difference is about $1000, maybe more than that even. That is more than 50% of the price...that is a BIG jump.
 
Joey,

What is retail on the Plinius SA102? I don't disagree with your review in anyway, but I doubt it is really a fair comparison to put the SA102 up against the RB1090. I can't imagine someone cross shopping those, but I guess anything is possible. In the used market it looks like the difference is about $1000, maybe more than that even. That is more than 50% of the price...that is a BIG jump.

Jim, retail is 6k, the 102 is no longer in production, recently replaced by the 103.

Joey's comparrison was because he was using a Rotel prior to the Plinius purchase (as was I, as a matter of fact)
 
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