#286

How is the calibration of serge modules? I’ve not read in to it too much but does it require an oscilloscope?

#287

I haven’t strictly needed a scope for most Serge modules, but it’s nice to have. A DSO is good for VCOs, and I like to see shots like this to confirm the operation of the R6 VCA for instance. https://modularsynthesis.com/serge/box1/serge1.htm

#288

yeah, calibrating diy serge definitely needs a scope… it doesn’t have to be anything fancy, but you need one to see what the modules are actually doing while you tweak the trim pots.

#289

Would anybody be willing to suggest a solid scope for use? This is a really silly question, but maybe using the VCV scope through an ES-8?

#290

My opinion is that if you’re going to use a scope at all, you should use a real DSO because it gives you the measurements and has proper inputs. The Rigol 1054 seems to be the default budget choice for DIYers with four channels but only 50mHz. I like my Siglent 1202X-E with only two channels.
If you look at the original instructions for Serge modules http://serge.synth.net/documents/kit_index.html you can see that a scope was not required for setup. It’s just nice if you want to make sure you have everything perfect and feel good about it. And it’s handy for troubleshooting and fixing/making other stuff.

2 Likes
#291

While this is true, my experience building current DIY Serge (R*S, some CGS boards) is that I really needed a scope to get things working well, especially the DUSG rates, Stereo Mixer pan and VCAs, and the Random/Noise rates/amplitude… If I didn’t have a scope I don’t think I could have calibrated them to be useful.

I use the same Siglent 1202X-E as @GrantB. It seems like the sweet spot for cost/quality in a budget scope.

2 Likes
#292

To calibrate the ez1073s with a multimeter, I made a termination cable with two 300 ohm resistors as shown here: https://www.montagar.com/~patj/db_db.htm.

Thanks for this. I think I finally have it figured out - and also it helps to make sure the EQ is disengaged :slight_smile: I’m using a voltmeter which is a good one but can’t really detect a -40dbu signal accurately (.00775v) and I couldn’t figure out why my voltage always seemed about half of where they should be. I rigged up a makeshift test cable using alligator leads and no resistors for now. I’ll document what I did below in case anyone else attempts the build…

  • Set preamp gain to 10 and sent 1khz sine to preamp from REW software
  • Monitored voltage and gradually turned up the output volume from my interface
  • -20dBFS was just above where I was seeing accurate readings on my voltmeter for my interface
  • This measured .025v at my unbalanced voltmeter which means .05v, balanced, or -24dBu
  • Turned preamp gain up to 60 which means I should see a 50dBu increase to 26dBu or 15.45v, balanced
  • 15.45v balanced = 7.725v unbalanced so I adjusted gain until I saw 7.72v on the meter
1 Like
#293

(the 1xx4 line all run the same hardware internally, and, as such, it is theoretically possible to bump a 1054 into a 1100 - the 100mhz model - with a single serial number. I couldn’t possibly comment on whether there is simple guidance how to do this online, or if I’ve done it myself…)

#294

Can anyone recommend a cheap DIY phantom mic preamp thing?

My main performance soundcard (RME UCX) only has two preamp inputs, and I sometimes I want to use my Sensory Percussion pickup with it, and sadly it requires phantom power.

The “sound” doesn’t matter too much, as the sound from the pickup is super noisy and tinny anyways, it’s just a matter of powering it.

Hell, something that powered off USB would be handy too as I can just plug into my hub and not have to deal with batteries at all.

#295

Dumb DIY question:

I have a bunch of MOTM-style power cables with mta156 connectors that are way too long for what I’m using them for now (a low profile Serge boat) and taking up way too much space in the boat. I’d prefer not to buy the mta156 tool as I’d only need it for a handful of connectors.

Is there any reason I can’t just cut, shorten, and splice my existing power cables, provided the splice is mechanically and electrically sound?

#296

I would gladly pay for a DIY/open-source module workshop/stream from someone here on lines. Soldering, panel design software, pcb software, ordering, resources, etc. I find the nearness thread very inspiring but overwhelming.

I will sleuth the forum for clues as usual but if others are interested in something like this, I would love to see it happen and would help facilitate in whatever way I could.

5 Likes
#297

Personally… I would not, even if it is mechanically/electrically sound like you say, because it always is until it isn’t, and by putting a splice in the cable you increase the chances of something possibly going wrong eventually. If the cord on your lamp is too long you wouldn’t just cut it and reconnect it in the middle with electrical tape and leave it like that (I’m assuming here I suppose…) because even if it could be fine for 20 years its an unnecessary risk compared to doing it properly.

If that solder joint goes bad at some point how much money and time is is going to cost you to maybe replace damaged components or a damaged power supply, or have something fizzle out in the middle of a performance or a nice recording session. Even if the chance is slim if you make little kludges like this every time when you need a proper fix/repair SOMETHING will happen eventually. Having things crammed in a shallow boat only increases the chances of a loose wire touching lots of things you do not want it to if it fails and increases the stress on the wire to begin with.

Granted these crimp tools can be stupid expensive - but I’m sure there are enough people out there who could whip up a few custom length power cables for you at a reasonable price that is probably far less than that of a new power supply.

#298

That is a very, very, very good point.

So anyone have a mta156 tool and want to make me some custom cables? :grinning:

#299

There are two types of tools for that connector, the really expensive type, and this one which I use: https://www.alliedelec.com/product/te-connectivity/59804-1/70089840/

You can also use a jewelers screwdriver to jam the wires in there, but after a couple of those you’ll wish you’d spent the $35. I have to think that after parts and shipping and whatnot you’d be in for more than that to get someone else to do it, depending on how many a bunch is.

1 Like
#301

Has anyone had a go at a liquid foam kit?

https://herbs---stones.com/liquid-foam/

looks a nice one.

3 Likes
#302

Any recommendations for a desktop synth diy? The more retro sounding (and midi compatible) the better :grinning:

I am eyeing up the paia fatman. https://www.paia.com/fatman.asp

#303

I don’t know if there is a more appropriate thread for this, but the following book bundle at HB has some electronics texts that may be interesting to people interested in circuit design. I can’t speak to the quality of them, so YMMV:

2 Likes
#304

I was exploring some samples I had purchased a long time ago, and got drawn in by these synare ones.

turns out, there’s a kit for a clone of it. pretty interesting demos on youtube, seems to sound similar to the original https://www.helensson.com/synare-3.html

1 Like
#305

I recently built the Norns Shield kit and loved it.
Just wondering if anyone has any recommendations for any desktop synths?

2 Likes
#306

I love my bastl kastl, was the first thing I ever soldered—very satisfying. The newer version seems like it expands the pallet a bit which sounds cool, tho I’ve never played with it.

3 Likes