Fantastic!!

Nate Dort wrote: Mon Mar 17, 2025 2:07 pm Somebody had recapped it about 20 years ago and converted to a diode rectifier. I only replaced that silver cap because it was bulging at the positive end (you can see it in the photo) and two 'lytics in the preamp that hadn't been replaced.

A few things here still have me confused:

1) What's the deal with the green 1uF ERO film cap? It's electrically in parallel with the bank of 40uF in the upper left corner. I've seen this done as a low-ESR high-frequency shunt, but a smaller value (0.1 uF or so) would be much more effective for that.

2) There's the four 470k carbon comp resistors in parallel with the rectifier diodes, which is equivalent to 470k between B+ and ground. Assuming 500 V B+, that's only ~1 mA of current, or about 0.5 W. They look to be 2 or 3 W resistors. Not sure what the purpose is here. It's not enough to cause any appreciable voltage sag, if one wanted to approximate the effect of the original tube rectifier. If there were parallel capacitors to help suppress switching noise, I could understand having 470k bleeder resistors, but there's no parallel caps here.

Nate Dort wrote: Mon Mar 17, 2025 8:23 pm 2) There's the four 470k carbon comp resistors in parallel with the rectifier diodes, which is equivalent to 470k between B+ and ground. Assuming 500 V B+, that's only ~1 mA of current, or about 0.5 W. They look to be 2 or 3 W resistors. Not sure what the purpose is here. It's not enough to cause any appreciable voltage sag, if one wanted to approximate the effect of the original tube rectifier. If there were parallel capacitors to help suppress switching noise, I could understand having 470k bleeder resistors, but there's no parallel caps here.

Its weird, but i've seen some DIY folks with too much time on their hands do this sort of thing as a cap drain in the name of safety.

Progress update on the Stagetec Nexus

After months of emailing, dealing with a pointless reseller, dropping half as much as I spent on the hardware on a piece of software (begrudgingly) some dude leaving the company resulting in my order falling into a black hole, and a short rant laced with standard issue colorful language, I finally got my hands on the Nexus Configuration Utility. It's a desktop app that basically lets you drag and drop cards around in your existing system and re-arrange them, and tweak some associated features. Once you've got it sorted out you export it and can then upload the resulting config files to the system. It's super locked down, only licensed to configs you own, and tied to a USB drive as a hardware key, so you can't export the final files if that's not connected. Fucking overkill on the lockdown, but whatever. Since they dropped the ball, they sped things up and just linked it to a thumb drive I already had rather than shipping one. So I fucked around with it a bit and managed to successfully reconfigure the layout.

So the third Base Device I got, (the 6RU box on top in the pic) has a newer iteration of their proprietary fiber network card, which unfortunately isn't compatible with the other two, so I mostly emptied that one out, and crammed as much as I could into the other two. It's CPU unit was newer and actually is compatible so I swapped that over too. It has some added features, like a network port for access from the control PC, and Loudness Monitoring.

As before the 9RU box is mostly AES3 digital stuff, I sacrificed one of the gpio cards and added the RJ45 AES3 card (16x16) and 12 Line AD inputs which wouldn't fit in the other box.

The 12RU box has 88 Line AD inputs, and 48 Lin DA outputs and 24 Mic AD inputs which have a nice little feature that basically clones it 4 ways so you can have 4 different gain settings for any given mic. Also, I'm sure I mentioned before, but the Mic cards have no analog pre, they convert A-D at Mic level.

So ultimately I had to sacrifice 4 Line ins, and a gpio card, but I now have a functional system with a total of 152 AES in, 72 AES out, 100 Line in, 48 line out, 24 mic ins, a gpio card, and a serial control card.

Now the fun part. Even with the super locked down software, there's room for hackage. The Software will let you save a config as an xml file to be converted to the system binaries later. The XML file is human readable and can be edited in a text editor, saved, and opened again in the software and it will reflect the edits. SO far I haven't really done a whole lot with it, but I have added a row to a Base Device, which could allow for cramming even more stuff in. Each of these base devices only has 2 backplanes, but some of the cards can be split from their faceplates, attached with a ribbon cable, and allow you to add more stuff. As for Physically mounting cards, it's just eurorack. a 3u Eurorack frame could be stacked on top and could hold more faceplates, with ribbon cables connecting to the cards on the backplane.

My biggest limiting factor right now is the incompatibility between the different generations of the fiber cards. If I get more base devices, I'll need to make sure everything is using the newer generation. The Config I'm using now, with the older fiber cards, is set up for only the 2 base devices. At the moment, this is fine, but adding base devices is NOT something I can do with the software (probably possible with the xml file, but I'm not qualified) I'm also told that's something an order of magnitude more complex anyway due to how the fiber network functions. BUT, I also have a config that came with the newer base device, that includes fucking 28 base devices. So if I get more hardware, and have newer fiber cards for each base device, I can build out up to that limit, which is...ridiculous.

The hardware is nearly impossible to come by at an affordable price. It's a fucking miracle I found two different sales for the prices I did so close to each other. I'll keep some saved searches going, but I doubt anything else will come along in my price range for a long time.

Anyway, I still haven't hooked a ton of stuff up to it yet. I'm using a lot of the AES I/O to feed into the Euphonix format converter so I can pipe MADI into my PC. I'm considering hooking it up to an analog console, and/or a bunch of outboard stuff to route through. I still haven't fucked with the serial, logic, gpio stuff at all yet, but there's potential for some fun stuff there too. This shit's ridiculous. I love it. Here's a pic of the new arrangement:
.

Congrats for having so much success and enthusiasm.
Let me stifle you by pointing out that it appears to be overkill for your requirements based on the adjacent milk crate.

Kind of reminds me of that hard disk recorder system fairlight or what was it?…radar;
High quality in some ways but so niche—really cool

Yeah, it's cool for sure, but what (the fuck) are you going to do with it?

scrotescape 4 real wrote: Thu Apr 03, 2025 2:18 pm Congrats for having so much success and enthusiasm.
Let me stifle you by pointing out that it appears to be overkill for your requirements based on the adjacent milk crate.

That milk crate is vintage, thank you very much.

Nate Dort wrote: Thu Apr 03, 2025 2:20 pm Yeah, it's cool for sure, but what (the fuck) are you going to do with it?

plug stuff into it.

Sony C-38B capsule swap. Got a third C-38B. No sound, but decent capsule. Swapped it into one of the others I got, which had a thrashed membrane. Now I have a working pair and a "needs repair" unit to sell.

A q: does anyone here have any tips for getting a very stubborn top-half grille off of an older (80s/90s) Beyerdynamic M500? I’ve pried the top off of other older beyers before but this one absolutely will not budge. The internal foam has disintegrated completely and is rattling around inside - I really want to get it cleaned out but I cannot get this thing apart and now already put a few “hesitation dents” let’s say in the grille of an otherwise previously pristine mic ;_;

thecr4ne wrote: Wed Apr 09, 2025 11:46 am Sony C-38B capsule swap….. Now I have a working pair and a "needs repair" unit to sell.

Interested