UGS MUSES Scion Preamplifier

UGS-MUSE-Scion-Preamplifier-small.jpg

Scion derives from the Middle English sioun and Old French cion and is related to the Old English cīth and the Old High German kīdi (meaning "sprout" or "shoot"). When it first sprouted in English in the 14th century, scion meant "a shoot or twig." That sense withered in horticultural contexts, but the word branched out, adding the grafting-related meaning we know today.​
Welcome to the official construction and build thread of the UGS MUSES Scion Preamplifier. The reason I am starting this build thread is to share, have fun and receive feedback and input. Since its heavily based on the original UGS (Universal Gain Stage) MUSE edition preamplifier developed by Alex_TWN and Eric.D over at homecinema-fr.com all credits goes to them for making my version possible. I ended up at the original UGS-Muse Edition preamplifier as a result of stumbling over the Pass Laboratories XP-30 line preamplifier which use the NRJ MUSE volume IC (New Japan Radio Co.ltd MUSES72320) and a few clicks later, the UGS-Muse Edition Preamplifier was a fact. This preamplifier will make it possible to develop and build a state of the art preamplifier, but with custom solutions.

This custom preamplifier is heavily influenced by Lyngdorf Tact Millennium MkII Digital Amplifier which is no longer manufactured. What really made Millennium Amplifier different was the volume attenuator wheel. It had a very lush and firm feeling. Nothing obscured the rotation and it felt like it could spin for ever, there where no mechanical input and no play - it was rock solid. I first encountered this amp back in 1999 and I still remember to this day the feeling, in other words, I got obsessed with it.

The third inspiration is 1970's style LED displays - very old school, but I am in love with does types of displays. Therefore the display information will use the LED Matrix style found via Liteon LTP-305HR - the same led display can be found in Soulution from Switzerland.

- July 2023 -

I have contemplated my options and have decided that the synergy of my forthcoming audio system will benefit greatly from the incorporation of vacuum tubes (triodes) in the preamplification stage and hence using solid state is out of the question. I am moving over to Allan Wright's RTP3 (Real Time Preamplifier) with some modern modifications and convenience. One such convenience is going to be the use of a remote to attenuate the volume and I am moving away from resistive based to inductive based.

This thread was a good learning platform and I appreciate the contribution. In due time, I will post a link to the new thread and this time, it will not be guessing or back and forth. I will present the project as it is intended to become. Some prototyping will be necessary to iron out some potential issues, but other than that, it should be relatively straight forward.

>> Watch this space <<<

Oneminde​
 
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Very intersting....Will you be selling boards for this project..?
Oh wow... hmm. Allow me to answer with; I don't know, followed by an explanation.

As you know, the original UGS-Muse Edition is not my work, I will use it as a base for my version which is a bit different compared to the original one. One of the differences will be no WiFi or streaming, that part will be take care of by the DAC. And due to a different front end as mentioned, the controller board will be redesigned.
As I write this, I don't know how the original designers feel if someone ells is making their cards available. This is something I have not investigated yet, and it might mean Alex_TWN and Eric.D want royalties. If this is not the case and cards can freely be distributed, then selling cards (kit) is not out of the question.

Do note that it will take a while for this project to be finalized, but if you are in no rush, by all means, stick around and follow the development and in time we will have a proper answer to your question :)

Oneminde




 
I'd also be interested in boards, if they become available.

Did some quick research, found this
UGS-muse preamp GB
Which appears to say at least some of the circuit comes from pass labs.

Randy
Its an upgraded UGS Preamplifier which I guess is inspired by Nelson Pass or Pass Labs equipment, so yes. The original UGS Preamplifier started to float around the diyaudio community in the mid 00's. I think I did a fare job of explaining why and how I arrived at the UGS-Muse Edition.

Project | Homebuilt Hi-Fi - A user submitted image showcase of high quality home built hi-fi components.

I'm not going to investigate the first UGS preamplifier since the later and updated one is fully realized.
The board kit could be an option as I mentioned. We will know when my version is fully developed.

Oneminde


 
A tiny update is in order.
Since I started a proper investigation and research on what's part of the UGS Muse preamplifier, I noticed that its been worked on in multiple stages, spread out in different threads & forums since 2005, with some editions going back even further than that and some options of doing it in at least two different ways. Not all versions will be included in my work as I have tracked down most of what's the most recent versions, but in order for things to be done properly, I want to make sure I understand the individual changes between the original UGS and the UGS Muse Edition.

Besides this, one thing that will change are the resistor and capacitor packages that will be no smaller than 1206 size (for enough heat dissipation).

So as they say, steady she goes :)

Oneminde


 
Very interested, i particularly like your choice of display...been waiting for someone to do this for a while.....

I have had the original UGS for ages and it is very very nice.
I think this one will be very nice in the end, especially since it will feature the Linear Systems JFet's. Beyond that, I want the best performing components, does not particularity mean the most expensive, rather material, construction and so forth.
The volume & display will certainly be very different and is one of the reasons this preamplifier will be made in the first place.

Darned obsession huh .. :D

Oneminde




 
I am studying in the background and collecting information, but figured I would present some interesting numbers.

Toshiba 2SK170 N-chn (EOL)
Gm; 22 mS
Ciss; 30 pF
Crss: 6 pF

Linear Systems LSK170 N-chn (Active)
Gm: 22 mS
Ciss; 20 pF
Crss: 5 pF

(Brand X) 2SK**** N-chn
(Active)
Gm: 35 mS
Ciss: 10 pF
Crss: 2.9 pF

Oneminde