Vitus Audio SM-101 User manual

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Gjellerupbakken 32, 7400 Herning Denmark Tlf: [phone]
www.vitusaudio.com
Table of Content
Introduction to the SM-101 mono amplifiers. .....................................................................................2
SM-100 history: ...............................................................................................................................2
Shows:..........................................................................................................................................2
Reviews:.......................................................................................................................................2
Awards:........................................................................................................................................2
Design:.........................................................................................................................................2
SM-101 differences vs. SM-100......................................................................................................3
Mechanical differences:...............................................................................................................3
Electronically differences: ...........................................................................................................3
Conclusion .......................................................................................................................................4
SM-100 Future.....................................................................................................................................4

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Gjellerupbakken 32, 7400 Herning Denmark Tlf: [phone]
www.vitusaudio.com
Introduction to the SM-101 mono amplifiers.
This document describes the main differences between the SM-100 and the SM-101.
SM-100 history:
The SM-100 was introduced at the Frankfurt show in May 2003. Since them it has been used at
several other shows like:
Shows:
1. Several private shows @ Peak Consult (Danish Speaker Manufacture) throughout
2003.
2. CES 2004 in the Argento, Soundlab & Vitus Audio room.
3. Private show @ Marten Design in Sweden, April 2004
4. Hong Kong exclusive show June 2004.
5. Taiwan shows in both Taichung and Taipei July 2004.
6. High end show in Tokyo October 2004.
7. Several smaller shows throughout Japan in 4Q04
8. CES 2005 in the Argento room and in the Vitus Audio room
9. Several other shows throughout Japan in 1H05
10. Focal private demo @ Focal in France March 2005
11. And many more…
Reviews:
1. HiFi Review, Hong Kong, issue 220 – 2004
2. Stereo Sound, Japan, issue 153 – 2004
3. Stereo Sound, Japan, June 2005 – together with the SL-100 Preamp.
Awards:
1. Product of the year award 2004 – HiFi Review, Hong Kong – 2004
Design:
The topology used in the SM-100 is based on more than 8 years research/development and uses
some very untraditional couplings. It is fully balanced from input to output and uses discrete
transistors only. The power supply used is single rail (Gnd and + 50V) with virtual gnd. The reason
for this topology of the power supply, what the intention to be able upgrade with a pure battery

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Gjellerupbakken 32, 7400 Herning Denmark Tlf: [phone]
www.vitusaudio.com
supply, as used in our RP/RL-100 preamplifiers. However with the development of the current true
balanced preamplifier, SL-100, we found that the micro dynamic performance and speed was
limited, unless using extremely powerful batteries (4x 60Ah for the SL-100). This, combined with
the future lead free production regulations, resulted in a complete change in our strategy in not
using batteries in any new developed products – and directly lead to the development of our current
shunt regulated power supply used in both SP & SL-100.
With this change in strategy, and the new extended topology used in the new preamplifiers, (which
includes an optimised input stage for even better linearity), we felt that optimising the SM-100
design was in place.
SM-101 differences vs. SM-100
Mechanical differences:
1. Heat sinks – the side handles and heat sinks on the SM-100 have been replaced with one
massive heat sink resulting in much better heat dissipation.
2. Ventilation in both top and bottom – this together with the extended heat sinks – gives
overall better lifetime and lower chassis temperature.
3. Handlebars on the rear panel integrated in the bottom, which optimises comfort when
carrying the units, and minimises stress on the rear plate.
4. Top plate extended to cover and protect all connectors on the rear plate.
5. Front display window is wider and now made of real glass instead of plastic.
Electronically differences:
1. Input stage from the SP/SL-100 preamplifiers used – this results in better linearity overall.
2. Further input protection added, which grounds unused inputs.
3. Overall signal length decreased by 70%
4. Dual rail power supply (it now runs of +/- supply which is the traditional topology)
5. 188.000uF instead of 94.000uF in the main power supply.
6. Further optimised transformer for even lower magnetic influence of electronics and even
less voltage drop (from open to short).
7. DC servo’s optimised further for typical max. DC error of +/- 10mV.
8. All amplifier stages work spots optimised for achieving the best possible result with the
current topology.
9. Bi cabling allowed via extra set of binding posts.

________________________________________________________________________
Gjellerupbakken 32, 7400 Herning Denmark Tlf: [phone]
www.vitusaudio.com
Conclusion
With these changes we have achieved the next level in performance, purely by optimising current
technology. We have spent many hours making sure that the SM-101 was not only a “design”
upgrade, but a total new experience in both sound and design. The SM-100 has been known for its
overwhelming overall performance, and we are proud of the fact, that making it even better was
possible. The sound differences between the SM-100 and SM-101 are:
1. Even deeper bass with more details.
2. Sound staging much more precise and 3 dimensional.
3. Better resolution and micro dynamics.
We hope you find the SM-101 as exciting as us and wish you good listening.
SM-100 Future
The introduction of the SM-101 does not suggest that the production of SM-100 will stop. We will
still keep production of the SM-100 running until further notice.
Best Regards,
Hans-Ole Vitus
Founder and CTO
Vitus Audio

________________________________________________________________________
Gjellerupbakken 32, 7400 Herning Denmark Tlf: [phone]
www.vitusaudio.com