Vitus SIA-025 integrated amp

Bodhi

Well-Known Member
Apr 20, 2014
1,051
361
155
Hi folks, having lived with my Vitus SIA-025 for a while, I thought it was time to post a review. Firstly the Vitus has wonderful Danish industrial design that is timeless. Everything about its design and attention to detail is excellent right down the the shipping materials and remote control (which is the best i've ever seen & is rechargeable). The SIA-025 is a true balanced, dual mono, 25 Watt class A amp which uses an efficient Vitus-designed UI-core potted "floating" transformer with separate windings for the left & right channels. The preamplifier stage is made from one single "buffer" module which is also used in the SL-102.. so .. really good, whilst the output stage is drawn from the SM-010 mono amps. The Vitus in every respect is the best integrated amp i've owned by a fair margin.

This amp is very flexible and has 100 watts of class a/b power @8ohms which is perfect for background listening or for movies, but can also be switched over to class A mode for best sound. At power up the amp defaults to class a/b operation and a moderate volume level of -46db from memory which I like, though i've heard atleast one other audiophile state he'd prefer the amp default to class A. I personally like the factory settings however.

But all that build quality would be useless if it didn't sound good! The easiest way to describe the sound of the SIA-025 is it sounds like real music. It avoids straying into sterility or sounding analytical by offering up a nice balance of warmth, tonal purity, richness (body) and tube-like liquidity. The Vitus has excellent resolution which reveals subtle, but important information in the music such as a bell chime in the background, or the light brush of a snare drum. It also has fast transients and can be delicate when the music calls for it. The treble is somewhat softened and the lower midrange slightly emphasised, giving the amp a sound resembling good vinyl. And the effect is cumulative as you add more Vitus components. In short, Vitus sounds best with other Vitus components. In saying that however, the SIA-025 is remarkably flexible. Not only because it can be switched from class a/b to class a, but also because this amp has the uncanny ability to sound good paired with a range of speakers and setups. It just "does its thing" and always produces great sound. Perhaps its ability to make average recordings sound very good extends to less than perfect speakers?

I also strongly agree with Chris Thomas's comments in his HiFi Plus review (http://www.vitusaudio.com/en/79663-Reviews#review-sia025-hifiplus92) in which he stated -

"From stand-by, straight into class A I would say that you are looking at a half hour before it really begins to sing and then it just seems to keep getting better. Even after a solid afternoon and evening's listening I would swear that the amplifier was growing more fluid, textural and resolute with better dynamic contrasts, tonal shading and the delicacy of its musical message just seems to become more profound."

As a side note, good isolation is very important to bring out the best sound from this amp. Notwithstanding the potted, floating transformer and anti-resonant chassis, stuffing so much gear into a modest sized chassis does create some resonance. Placing the amp on a solid rack with Stillpoints Ultra 5's and an Ultra LPI on top made a big difference which created a blacker background, improved bass & brought the sound stage into clearer focus. I now consider the Stillpoints mandatory with the Vitus Sig Series such has been the level of improvement.

But has it got balls? That is a question I get quite a bit. With "only" 25 watts class A power, on paper it doesn't look like this amp is capable of driving a full size speaker with a moderately difficult load. Let's look a bit deeper. Most of the amp's real estate (and 42kg weight) is taken up by a huge 1.4kVa Vitus-designed UI-core transformer. Most audiophile-grade toroidal transformers lose up to 25% voltage (both channels driven), however the Vitus loses max 1.5% voltage tested. It is also a very high current amp, meaning that 1.4kVa tranny feels more like a big 2kVA tranny. In practice I have found the SIA-025 drives my Magico S5's without breaking a sweat and at only 140hrs is already delivering deep bass and a nice, coherent sound stage. Of course once my amp and speakers reach 500hrs the bass and sound stage should open up even more & sound more resolving.

In summary, this is a sublimely good integrated amp. I never thought i'd find an integrated which would convince me to dispose of my previous Boulder 1060/1010 combo, but the Vitus achieves that feat and sounds like very good high end separates. That revelation coincided with a wish to reduce my box count and change direction with my system. What I didn't realize at the time was how much of a sea change that would prove to be!

Cheers.
 
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LL21

Well-Known Member
Dec 26, 2010
14,411
2,509
1,448
Great review, great read. Congrats. I have never had the good fortune to hear Vitus electronics, but [think] I have some idea of what you speak with my Gryphon (also Danish, also Class A, also 'massively overbuilt'). And its a keeper for me. Enjoy...really like your system, and also have found excellent results with Ultra 5s under my Gryphon and have damping on top. In my case, on the damping, I have found an Artesania damping plate with a 20kg brass weight on top sounds best. My floor does have a lot of vibration running through it, and the mass part of my damping really helps.

Enjoy your system...looks extremely well thought out in selection of all the equipment.
 

Bodhi

Well-Known Member
Apr 20, 2014
1,051
361
155
Thanks for your generous comments LL21. Yes I think these two great Danish brands have some similarity, and of course wonderful Danish industrial design. The Gryphon Collosseum is a great amp and excellent choice to drive your Wilsons. With my raised hardwood landing & Taoc racks, I have found Just the Ultra LPI to be sufficient to damp the top plate. I am really shocked how well these devices work. And they look great. Your solution sounds well suited to your acoustic environment. I admire that level of passion in audiophiles!

I am inspired by the vision I have for my system, and look forward to posting a major update around the end of the year :).
 

audioline

Well-Known Member
Mar 24, 2013
61
1
913
Denmark
The Vitus SIA-025 is really a great amplifier, it sounds BIG, lot's of details and a great soundstage. Products like that, makes me feel proud of Boeing a Dane :)
 

JackD201

WBF Founding Member
Apr 20, 2010
12,308
1,425
1,820
Manila, Philippines
The Vitus SIA-025 is really a great amplifier, it sounds BIG, lot's of details and a great soundstage. Products like that, makes me feel proud of Boeing a Dane :)

You should be proud. The 025 is a true gem IMO.
 

Orb

New Member
Sep 8, 2010
3,010
2
0
Thanks for posting your review Bodhi,
what I also love about this model is that it has the WAF; looks smart-clean (uncluttered) and importantly does not take up too much of a footprint.
Would not be out of place in nearly any home IMO.
And style-ergonomics I feel are becoming much more critical these days, where one also expects these days exceptional sound with such designs.

Thanks again.
Orb
 

Bodhi

Well-Known Member
Apr 20, 2014
1,051
361
155
Hi Orb, thanks for your comments. I agree, the SIA-025 has very attractive Danish industrial design and looks timeless. I'm single, but my Mum gave a tick to both its looks and sound. As much as possible i'm trying to reduce my box count, and the Vitus fits in perfectly with my system plans. The fact is has great synergy with my S5's is the icing on the cake.

Cheers,
Bodhi.
 

Bodhi

Well-Known Member
Apr 20, 2014
1,051
361
155
Hi Cannata, not in my system. I've used my Jorma Prime cables from day one, though I have heard Magico Q1's with an SIA-025 & SCD-010 with Siltech Royal Signature series cables and thought that was a great match also. The Primes suit my tastes as they sound natural/organic, harmonically rich and have a level of resolution and refinement which is exceptional. There is also some natural warmth. Once you have experienced these two cables (Prime & Royal Sigs) the differences are easy to detect. They are both great in their own way, so it comes down to which better suits your room, system and taste. The Siltech cables use G7 Silver/Gold conductors, whilst Jorma are using the purist possible copper & gold, transparent Teflon, ceramic fibres and walnut. The Primes also use Bybee Slipstream Golden Quantum Purifiers which give the cables a mellifluous sound. In summary, I would say the Royal Sigs have a bit more bass and are perhaps a bit richer sounding. Primes are more neutral and organic, with a wonderful touch of warmth.
 
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Bodhi

Well-Known Member
Apr 20, 2014
1,051
361
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Hi Trevor, thanks for your comments. I appreciate the warm welcome i've received from you and many other members since joining :)
 
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Barry2013

VIP/Donor
Oct 12, 2013
2,305
487
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Essex UK
Just found your review of The Vitus SIA 025.
Just to say how much I agree with you. Got mine about 9 months ago - ex dem and the one used by Chris Thomas for his review. Also wanted to reduce box count but not entirely successful as I got hooked on the Silver Tellus(2) and very recently an Atlantis box to hook up to both.
I am using Entreq i/cs and speaker cable which work very well with the amp together with Stillpoints.
 

LL21

Well-Known Member
Dec 26, 2010
14,411
2,509
1,448
Just found your review of The Vitus SIA 025.
Just to say how much I agree with you. Got mine about 9 months ago - ex dem and the one used by Chris Thomas for his review. Also wanted to reduce box count but not entirely successful as I got hooked on the Silver Tellus(2) and very recently an Atlantis box to hook up to both.
I am using Entreq i/cs and speaker cable which work very well with the amp together with Stillpoints.

Hey...the good news is you got the same number of boxes...but seems like they give you MORE performance. ;)
 

Barry2013

VIP/Donor
Oct 12, 2013
2,305
487
418
Essex UK
Hey...the good news is you got the same number of boxes...but seems like they give you MORE performance. ;)
Thanks Lloyd.
Absolutely! And you played your part when you assured me that adding the Atlantis box would improve the sound. You were right and belated thanks for the encouragement.
All being well should be upgrading to Apollo i/cs in the near future which should improve things still further.
 

LL21

Well-Known Member
Dec 26, 2010
14,411
2,509
1,448
Thanks Lloyd.
Absolutely! And you played your part when you assured me that adding the Atlantis box would improve the sound. You were right and belated thanks for the encouragement.
All being well should be upgrading to Apollo i/cs in the near future which should improve things still further.

I am glad that worked well for you...enjoy! Good luck with the ICs as well. I have not heard those.
 

Bodhi

Well-Known Member
Apr 20, 2014
1,051
361
155
Just found your review of The Vitus SIA 025.
Just to say how much I agree with you. Got mine about 9 months ago - ex dem and the one used by Chris Thomas for his review. Also wanted to reduce box count but not entirely successful as I got hooked on the Silver Tellus(2) and very recently an Atlantis box to hook up to both.
I am using Entreq i/cs and speaker cable which work very well with the amp together with Stillpoints.
Thanks for your kind words Barry. I have Chris' review on my desktop. That was a good read, so your amp has an interesting history! Great to hear you've achieved good synergy with your system :)

I agree with the principle of proper grounding for upstream components. I am currently looking into that, as well as adding robust protection against overvoltage and surges.
 

Barry2013

VIP/Donor
Oct 12, 2013
2,305
487
418
Essex UK
Thanks for your kind words Barry. I have Chris' review on my desktop. That was a good read, so your amp has an interesting history! Great to hear you've achieved good synergy with your system :)

I agree with the principle of proper grounding for upstream components. I am currently looking into that, as well as adding robust protection against overvoltage and surges.

Chris Thomas is a really good reviewer and I have great respect for his judgement. His most recent review for HiFi Plus of the Estelon XC speaker was IMO a master class in how to review a product.
My experience of the Entreq grounding boxes has been extremely positive throughout. They really reduce the noise floor and allow the music to breathe and shine through. As you have probably read there has been something of a debate in WBF about the respective merits of Entreq and Troy. Clearly both are very effective and beneficial. I have only heard the Troy once and it did not sound better than my Silver Tellus, but the system and room were very different from my own. I find the Entreq more user friendly - no power cord to worry about - and you can upgrade in stages. Having said that I would on the basis of my experience start with the Silver Tellus rather than the base Tellus
 

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