UGS-muse preamp GB

[starcat]

No, you are fine with one encoder on the right and the buttons.

The 2nd one is nice if for some reason you can not mechanically implement the buttons. A hole for a 2nd encoder is easier than putting numerous buttons on the faceplate. Also the 2nd encoder is nice for optical symmetry, if this is what you like.

Yes, the firmware supports currently

• main encoder (on the right) with buttons (original design)
• dual encoders only (functionality added later)
• dual encoders with buttons (was left as some liked it and could potentially use the buttons as direct inputs select, etc)

 

[Pars]

Thanks for the info. Dusting off my memory as it has been awhile since I've looked at this project.

 

[schultzsch]

One of the files was posted here in the past and has the description for the push buttons and encoders also, the other file was edited and has the description only for the encoders.

The other attachments are my blowtorch clone for which I recently finished the pcbs.
If someone want to try it can be found online shared by Milan, search for Uskok.

 

[Pars]

Are there any reliable sources for ZTX450/550? Or are there substitutes for these? Looking to source enough for 1 preamp, possibly 2. I can get the 550s from onlinecomponents, but not finding the 450s anywhere that I feel is 100% trustworthy. Would prefer to get both from the same source, but that isn't mandatory. Thanks!

https://octopart.com/search?q=ztx450&currency=USD&specs=0

 

[starcat]

Farnel/Newark has the 450, grab some as long as they are there

 

[Pars]

Yes, they have the 450s. No 550s there.
Are these the best parts to use (i.e., is this what Pass used)? There are lower noise parts than these, but haven't looked at all the specs. Also, does the eline package fit the heatsinks with the SJ109/SK389 better than a reg. TO92?

 

[starcat]

Not sure if this is TO-92 or E-line 450/550.
Looks maybe like E-line (thickness 2.16-2.41mm), but they are as thick as the SJ109/SK389

Yes, definitely E-line.

 

[Pars]

Those are the Zetex e-line TO92 version that is flatter than a normal TO92. I had just wondered if those fit the heatsink things that they designed better by matching the thickness of the JFETs better.

 

[starcat]

Those are exactly as thick as the as thick as the SJ109/SK389 packages, which makes them fit perfectly the heatsinks.
Get these if you can.

 

[Pars]

Ordered the 450s from Newark and the 550s from onlinecomponents. Also ordered a couple of Muse chips from Profusion. Even with shipping to US, cheaper than Mouser (and they have them).

 

[schultzsch]

Finally the pcbs for the blowtorch arrived

 

[fencki]

can you explain what the „blowtorch“ is and how to use it with the ugs muse preamp?
maybe a stupid question but i really have no clue…

 

[schultzsch]

Not stupid at all!


It’s a line stage without global feedback, it was designed many years ago by John Curl.
You can find more info searching for Moxtone Uskok.

I dream about this baby for many years… but at that time I didn’t have the knowledge to put it together, not that now I have a lot but I did a bit of progress lately.

To use it with the ugs preamp you just remove your actual gain and buffer modules and plug in this pcb.

 

[fencki]

so it is instead of the 2 small pcb‘s for buffer and and gain stage? a drop in replacement?
or you have to rearrange everything?

 

[schultzsch]

It’s a drop in replacement

 

[fencki]

can you show me how to attach it to the ugs muse board? i can’t figure it out from the photos

 

[schultzsch]

Just remove the old pcbs and plug these on keeping an eye to have all connectors centered.

 

[fencki]

very intersting.

 

[schultzsch]

With the blowtorch in my collection I have 3 line stages that I can flip between them depending on the music, on my mood and on the weather outside

 

[starcat]

Would be ape to have them all in and switch between them via relays or something.