Someone on Facebook semi-accidentally pointed me to the first photo I put up of my studio. Welcome back to 2009:
SO EMPTY. So unconditioned! So… echoey! It didn’t take me long to start building more sound baffles, I remember that.
I particularly like the weights set. In case, you know, I needed to do some sets between… sets. XD
Here’s the same room now, three full-length albums, an EP, and a couple of singles later:
I just spent the whole day – daytime day, I quit at dinner – rewiring my studio to better isolate the AC power lines from everything else, because it’s pretty clear at this point that our AC power is just scary with RFI, and the new high-gain preamp is AC all the way to its motherboard, unlike everything else, which is DC power once you get past the adaptors.
Result? All this did NOT A FUCKING THING for the high-gain preamp. In fact, it’s worse tonight. Enough that were I trying to use it, it’d be difficult and I’d have to be stupidly careful with cable placement, or something, and hope I get lucky.
At that point I thought I’d achieved nothing at all, and had in fact fucked it up somehow – which didn’t make any sense but that’s never stopped me before – until then I poked at my primary input board for semi-unrelated reasons, and HOLY HOPPING CHRIST ON A POGO STICK the difference.
SO MUCH QUIETER so much quieter
Even at max gain, zero input shows up as zero on my main input board. It’s not actually zero – I can hear it – but it’s too far down to light the metres, which puts it at somewhere around -75db.
So at least I didn’t fuck things up. That is a thing which is good to know. I actually achieved my design goal for the rewiring, to a surprising – nay, astonishing – degree of success!
And it did absolutely fuck all for the problem.
goddammit.
I’m still sure AC Power is a problem though, because if I plug the preamp straight into the wall, the RF pick up is REALLY LOUD; through a computer power strip (which filters, some) it’s less; through the battery-backup and power strip, less still. I suppose it’s possible there’s another reason for that, but I don’t know what it would be.
eta: I took apart the preamp, convinced myself of a few problems, maybe improved it, maybe the RFI just calmed down a bit on its own. Who knows? Here’s a recording of a suboptimal cable position after the resoldering. That’s boosted all to hell, of course; at normal recording levels, it’s inaudible, but I hate that it can be found. It’s also still cable-position-dependent. I tested literally every cable I have; this was the most RF-resistant one. If I have it on the right side of the mic stand, it sounds like this. On the left: no audible signal.
eta2: I opened up the case again and twisted the internal side of the AC power lead (9v AC) as tightly as I thought I could get away with. The test afterwards contained far lower RFI than previous tests, but that’s not necessarily meaningful – it’s a different time of day. (All my previous daytime tests have been mid-afternoon.)
That said, for the first time, there was no sign at all of KUOW 94.9, which may be a first. And I didn’t hear BBC World Service in there either. I was picking up KIRO, dimly – but I don’t know whether I was picking up the AM or FM station. Most of the time they have separate programming, but they simulcast during Seahawks handegg, from pregame through post, and that’s what was on. And I had to dig at it to get that much, which is actually good – if I can’t stop it entirely, I can at least make it something you really have to work to find.
So, yeah. Ongoing. I think that twisting the internal AC power lead bumped it down another level. But I’m not sure. It gives me some hope that the RFI chokes I’ve ordered might help.
Fucking ghosts.
I was picking up radio on the ribbon mic’s pre-amp, at really high amplification gain. Ribbon mics need tremendous gain, because the base signal is so low, which meant this mattered. It wasn’t enough to appear in most – emphasis on most – recording situations, but I didn’t want it at all, because it indicates a potential circuit problem.
For the record, you start listening to EMF noise boosted by 96 to 142db (from extremely low levels), and you start chasing some serious fuckin’ ghosts. Somebody get me a skiffy channel show, stat.
Anyway, earlier in the day, I’d gone through all my patch cables, isolating the most RF-tight via comparative testing. It was a pretty big range. But even the best ones were still picking up some of that radio sound, and with some work, I could get it in clearly – tho’ always at extremely low levels.
Now, before I set about finding my best patch cables, I’d isolated out the microphone connection, to reduce complexity and eliminate other noise sources.
Turns out, a 3mm run of unshielded null signal wire can bring up a surprisingly durable amount of RF, in the form of BBC World Service on shortwave. Pulled that back out, popped in a microphone cable (connected to the ribbon mic): no more radio.
The goofy thing is that Cascadia is notorious for shitty shortwave reception. I can’t get BBC World Service reliably on my shortwave radio. AND YET.
At least it’s sorted, now. I still need to evaluate a few more cables, but the explanation is in hand, and that’s the important thing.
So over on Tumblr, I got a new follower, maksimoqqoman. And despite the crappy username, I thought I’d check it out. It brings up a possibly-relevant promoter’s page, which is all well and good, despite for the autoplaying music video, but whatever.
Then pops up a modal dialogue box saying “Check out some great artists below,” with a single “close” X in the upper right and no other controls, and the rest of the page is locked out. Fine, annoying, but you get a lot of that brick-wall experience these days. It makes me very unlikely to look at your site again, but whatevs.
THEN it gets good, because the “close” X? It’s not actually a close. IT’S A HIDDEN FACEBOOK LIKE FOR AN UNRELATED POLITICAL GROUP. Which I discover as soon as I try to close it.
Am I, like, the last to know about this? Because there are not enough efs and uuuuuus for this situation. There just aren’t.
Ever wondered how thin a ribbon microphone ribbon actually is?
That’s how thin. Edible gold leaf is much thicker than this.
You take aluminium this thin, cut it into strips, then corrugate it with great pressure, with wood, all by hand. It’s not as difficult as it sounds, but once it’s done, it’s like “…wow, that’s… really delicate work!”
I’ve made a couple of viable ribbons at this point and have been testing the completed microphone. This ribbon had a nick on the edge, so was useless, and never made it to the corrugation stage. I threw it out, then fished it back out of the bin for a photo.
You can’t actually touch them; they disintegrate on contact. The toothpicks shown here are for handling the metal.
I’ll make a microphone assembly post probably tomorrow.
eta: I just tried to measure how fast it falls (terminal velocity), and it fell about 60cm before deciding to hover there for a bit. Presumably in an updraft I couldn’t feel, not just out of sheer orneriness. So I’m guessing around 10cm/second? Except when it just doesn’t feel like it.
The preamp is sensitive to my personal EM field.
Awesome.
I’ve written the Austin people. Hopefully we’ll get something.
I also been building the ribbon microphone. I think it’s okay! But I can’t be sure yet because I don’t have the right preamp. The mic seems to work fine on the TASCAM – go me! I made ribbon microphone ribbons! – but it lacks adequate gain, so that’s not a workable solution.
Bed now. Work on this tomorrow.
eta: This is still true, but it looks like I can shield around it – it’s in no small part a cable-as-antenna question, and my best cables shield me out – I have successful tests again! n/ Austin Microphones is being super-responsive, too; well done there.
I built an Austin microphone preamp from a kit! It’s for use with ribbon mics, and also dynamics – it doesn’t supply (and cannot be hooked to something which supplies) phantom power, so it’s pretty special-purpose and will never leave the studio. But given that I’m about to have a ribbon microphone, it’s useful! And hopefully fun. Anna made me promise not to blow anything up; when I told her that horse had left the barn, she added “today,” and upon checking the clock I found I could agree.
The kit came in a bunch of components and a few machined parts in an assortment of bags. You also get a PDF with extremely detailed directions. See that printout to the right? You get a bunch of those, along with step-by-step instructions.
Building is therefore pretty simple, as long as you know how to solder, can keep your solder under control on a fairly but not screamingly small experimenter’s board – you’ll want a good soldering station, mine certainly earned its keep – and can follow directions carefully.
The supplier even provided all these little jumper wires already cut and stripped! Everything else needed cutting and stripping, though.
The supplier said it should take about four hours; it took me rather longer, mostly because of the current limitations in my vision slowing me down. I was also very careful and methodical, for the same reasons. Even with all that, it’s still just a one day project.
Paul asked me right about here whether I was making any headway on that dematerialisation circuit.
This is what it looks like when you’ve finished the converter array and have the power rails all set up.
The manual has you do testing at this point, and provides several key warnings. The checkbox-as-you-go system really makes it harder to miss things or to get things wrong, as long as you keep up with their grid system. Thanks to my still-recovering vision, I was checking every solder joint under magnifiers.
The kit has two ICs: THAT and OPA chips. I don’t really know why I find that hilarious, but I do.
Once the chips have been installed in their sockets, it’s time to start adding I/O ports! This one has balanced microphone input, unbalanced line-level output, and external power connector socket. There’s no power switch; it’s just plugged in to turn it on, and you connect power FIRST – before plugging in to any other hardware like the microphone or the input card – and then remove power LAST, when taking down. This is opposite to my current hardware; I’ll have to add reminder labels.
That, and the whole phantom power thing. It’s an odd beast, for an odd sort of microphone.
Input is boosted enough and output is loud enough that you can test it with headphones; no separate amp required. At the highest power levels, I was honestly kind of astounded at how much gain it had, and quite pleased with the noise levels even at maximum boost. First test of the complete assembly passed just fine.
The printed control panel looks rather smart, I think. It only has the one control – a stepped gain control knob – but it has a good range of boost steps.
I can’t say a whole lot about performance yet – but I can say it’s very low noise at very high gain, and had a nice natural sound on my quick SM-58 tests. The real test will be the ribbon microphone I intend to use with this amp, which is also a kit. Despite fewer pieces, it’s a longer build – there’s materials time, and unfamiliar processes.
But I’ll get there. I’m just hoping my studio is up to gear this shiny. ^_^
This is a related article in the Studio Buildout Series, a collection of posts on building my own recording studio.
Second Thanksgiving went well; we had 15 people, as it turned out – a nice size. We were expecting possibly as many as 20, so had a 30 pound bird for the first time in years – but that’s good, because mmmmmmm turkey tacos, mmmmmmm turkey jos, mmmmmmm turkey leftovers on sammiches, etc. 😀
It ran late, into the night, and felt a lot like one of the Homeless Waifs Thanksgivings our housemate Vicka used to throw, before she got her doctorate and moved back to Boston. I don’t know exactly why, honestly; it just did. Good circulation and a crowd large enough to form several groups made up part of that. More new people than usual probably helped too, I suppose.
I imagine the return of the Mystery Science Theatre 3000 Turkey Day Marathon didn’t hurt anything. I missed that – we were singing the “We Gather Together (To Watch Cheesy Movies)” theme over and over again while cooking. We named our turkey Clayton McLargehuge, in honour; Anna told @JoelGHodgson about that on Twitter, who retweeted it. XD
Also, we need more Thanksgiving songs. One isn’t enough.
My long-term undefeated Jenga streak fell this year, I hate to say; that lack of parallax thing really hurts when it comes to tower stability wars. Even when winning the first game, I was telling people, I could feel it – I could be owned, in my current state. And was, alas, the very next round.
We had more music than usual, too, with LasFas and Fred both being around and having more time than usual, and with me and Anna, that made a pretty good bit of jam.
The last people left Saturday, which says a bit about it. We overbought alcohol (darn) and food (like we always do) but it’s all being eaten and much will be frozen or stored.
For real, this is my favourite holiday. How was yours?
Whelp, the CD burning robot seems to have packed it in pretty good this time – doesn’t respond to commands, does randomly flail tiny arms around… I’ve managed to revive it before, but it’s never been this random.
I’m thinking of getting a multi-disc stacked CD duplicating controller and some CD burners – I was looking at this controller and this case (which appears to be fine as long as you don’t get a dodgy power supply with it) and a bunch of burners.
The problem is that SATA burners are all multi-layer and Blu-Ray (and thus expensive), while PATA/IDE burners are exactly right and cheap, but PATA controllers are hard to find, particularly given that Amazon has started blowing off search terms like SATA and LIGHTSCRIBE, because apparently they just hate everyone now.
Or I could buy this off of eBay, assuming it actually is five burners and Lightscribe – since the description does not match the title which may not match the photo (the photo looks like Sony Optiarc burners which lack the Lightscribe logo), I’m not sure!
Adventures. Any thoughts?
In addition to today’s DIY post on monitor speakers, this past weekend was more or less nirvana for Doctor Who fans. If you missed them, I did a 50th Anniversary reaction post called Okay, Moffat, You Can Live, and a second post on the surprisingly delightful related short features. Enjoy!
THE NEW SINGLE
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