Archive for the ‘recording gear’ Category

a waveform sung into a can

I have a waveform! I did a bunch of testing of various parts and such, discovering that the carbon transmitter (microphone) I had was indeed fully functional, and really, it came down to “not enough voltage.” 1.5v is pretty borderline for carbon microphone power, so that’s fine.

The waveform is kind of lopsided, but that’s because this test harness doesn’t have the balanced output yet; I’ve ordered the balanced transformer, and that should help. It’s also a bit noisy – here’s a sample – which is partly related to SHIELDING WHAT IS SHIELDING because it’s a test harness.

Talking of, here’s what version one looked like:

This is a direct implementation of the first half of the circuit described in this instructable, which runs off a 9V battery. Once the rest of the circuit is added, it’ll have balanced output, which is pretty snazzy.

This is a closer view, and also after I added an LED, because hey, LEDs!

After that, I tried a smaller capacitor, and that’s working fine – mostly, I’m just picking from what I’ve got, which goes along with what the circuit designer described.

I’m going to play more with the circuit a bit, pending getting the matching transformer. And some shielding.

And, of course, the can. 😀

ps: this harmonica “bullet mic” looks pretty cool too.

oh dear it’s another project

Or more correctly, a few other projects. Or hilarious things I found out.

ONE! I need a bullhorn for the chorus of this song. YES A BULLHORN. Yes, I can fake it with plugins but searching around for advice online, the most common answer by far was Just Get A Bullhorn, They’re Cheap. And they are, you can get a decent one for $9.

TWO! I’mma gonna build a carbon button microphone – think antique telephone, like those things from the 1930s-1960s – and nobody can stop me. Turns out the parts are cheap and you don’t have to spend $250 for that one from Gold or whoever.

THREE! As I posted on Facebook over the weekend, turns out those old Square credit-card readers for your phone or tablet that let you take credit cards at shows? They’re purely analogue devices, which is why Square upgraded everyone for free last year. Meaning they output sound. Meaning I just recorded the audio of my Costco card and this is hilarious.

I need some quarter-inch magnetic tape, stat. XD

floppy-disk delay pedal, what?

A Germany company has shipped a delay fx pedal that uses a floppy drive as magnetic media to run its delay. That’s… interesting… and strikes me as likely to be really noisy, but on stage, probably not enough to care.

What makes me think about it more is data rates. Are they floppy-native digital? Are they formatting mp3? If so, 320kbps is very high quality, and the faster floppies managed 500kbps, so we’re good there, and you could ignore FAT and just write a digital data stream at that speed, it’d work.

But what if you intentionally racked that down? I kind of like the idea of intentionally under-quantising your delay pedal. Crank it down to 48kbps or something, have your delay sound like a cranky land telephone line.

Or maybe they’re bypassing the digital part entirely – what does floppy drive sound like as an analogue magnetic media? What do dropouts sound like on a floppy disk?

That would also let you play with different rotation speeds, of course.

Oh wait, look, they have a video. (Scroll down at the link.) Apparently, it’s analogue. That’s fucked up! I kind of like it. But it does lose the possibility of digital data loss, which – depending upon what you’re going for – is kind of too bad. Low data rates combined with this environment could make some really awful/awesome noise.

eta: In comments, John posted a link to this awesomeness, go play that, you need to right now.

tube-driven microphone preamp

Leannan Sidhe and I were kicking around at an estate sale – she was looking at some PA kit that had been advertised, turned out really not interesting – and I noticed a little neglected microphone pre-amp sitting in the corner. I’ve never bothered with separate microphone pre-amps, much less tube-driven ones, but I was curious about it.

So I went to the manager running the show, and said, “I don’t need this, but it might be fun to play with, what’s your best price?” And so I strolled off with it, and today I set up a pair of side-by-side M-Audio NOVA large-cap condenser microphones to make some simultaneous recordings. Both mics ended up going through my TASCAM interface, with one going through the tube preamp first, then to the TASCAM with the TASCAM’s gain cranked down to zero. The control mic gain on the TASCAM was set to match final recorded levels. A few samples are linked below.

First thing I noticed: jfc this thing has gain. If I need something LOUDed at the pickup level, I now have that piece of kit. I kind of had that kit already, but that was the ribbon-mic preamp I built specifically for the ribbon mic I built, and that can’t provide phantom power like this does. (And it shouldn’t; phantom power destroys some ribbon mics, including mine.)

The second thing I noticed is that… the difference is pretty subtle. I mean, I expected that. And part of that might’ve been having both lines going through the TASCAM at the end – but it had to go through something for digital conversion, or I can’t record.

In studio, I can hear small but audible differences. The TASCAM’s preamp seems to like mid-bass more than the ART TUBE MP. I think there’s a little quicker response in low base in the ART, in a way that I recall from tube amplification equipment like EICO and Dynaco gear.

Outside the studio, though – on a good consumer headset on my laptop? I’m not hearing much of any difference in 320kbps mp3. I think I’m hearing a little in uncompressed WAV files, but not a lot. That may be the laptop’s D/A converter, I don’t know. On the laptop speakers, I don’t hear anything different – though really that has to be expected.

Worth it? For what I paid, sure! I have a serious business gain DI/pre-amp out of it. Sound-wise? I dunno. I really do think there is some subtle difference and if I’m in an environment where I’m having to rein in mid-bass and pop the low end a bit, maybe it’d be better to do it with this thing than in equalisation later. Probably would be, in fact. But it has a pleasant enough sound to it, regardless. I’ll probably play with it on bass guitar, later.

Anwyay, here are some recordings – they’re edited so that consecutive repeated musical phrases alternate between the ART tube amp and the TASCAM interface’s built-in mic preamp. What do you think – do you hear anything?

Irish bouzouki: WAV mp3
Octave mandolin, tuned to open E5: WAV mp3
Bodhran, two different strikers (traditional, bamboo): WAV mp3

eta: I make a point of not talking American politics here much, but I do elsewhere, and watching the GOP’s civil war start in earnest is kind of neat.

an xwindows question

On my digital audio workstation, I run two monitors, and I do it in xinema mode. This is because Ardour – like the overwhelming majority of apps ever – wants all its windows to be on one desktop. xinema mode is how Xwindows does that.

It’s great for Ardour. I have mixer on one screen, editor on another, it’s lovely.

But a couple of system updates ago, a lot of apps started getting “better” ideas about where “centre of screen” is, by which I mean, instead of getting centre of monitor, they were getting centre of desktop.

Which means that many applications now start split in half across two monitors. Including, annoyingly, Ardour’s startup menu and open-file menu; it remembers opening positions for main windows but not startup dialogues or splash screens.

This is incredibly annoying.

So is there a way for it to get, idk, “monitor centre” when it asks for “screen centre,” or to set a default location for unspecified-position windows, or… stuff? Because yeah. Annoying. So annoying.

Looking for the Grammy Awards Long List nominee post? Thank you for listening, and for your consideration.

this mic kit looks fun

Over on Facebook, Boris L. tagged me on a link to this instructable on making a steel can microphone. I don’t care much about steel-can microphones (though they are apparently a thing?), but I was curious about the actual pickup element inside. That pickup turned out to be this balanced-output piezo contact microphone, which comes in a kit form for reasonably little money.

The assembly instructions for it are online. As I’m reading, hanging around in the back of my head have been these pressure zone microphones (generic name boundary microphone) that I’ve performed with once, and have seen discussed several places. They’ve always struck me as kind of interesting to play with, but never enough to justify purchase.

You can probably see where I’m going here: the outdoor versions of these PZMs look a lot like contact pickups attached to sheets of rigid plastic, suspended in air via a cord framework. I can certainly build that.

I’m considering a couple of designs, but this is my thinking: since this element is a piezo, it works best with direct contact with a resonating body. That could be a sheet of rigid lightweight plastic, much larger than the pickup, to gather sound and resonate. Hang that sheet-plus-attached-pickup from a rigid outer frame, using some form of elastic suspension. Low-density foam might work, for example, like with a speaker. Then that can be hung anywhere.

That’s the simplest of the ideas I have, and makes sense in that sniff-test kind of way. It’d be large, but every mic of this type I’ve seen has been large, so that’s fine. Depending upon what happens, I could also poke around with hanging it on walls, as is the usual use for boundary/pressure-zone microphones.

So, yeah! I won’t get to it immediately, but when I do, I will of course post about it. Mostly, I’m hoping I don’t have to build some sort of multi-layer frame around the large plastic pickup plate. That’s one of the more complicated designs. I could do it, but the more complicated these things get, the worse they tend to sound.

If you have any design knowledge of these sorts of things, share some knowledge in comments! I haven’t seen other attempts at DIY PZMs using this approach, which kind of surprises me. That might mean it doesn’t work at all, but it might also just mean nobody else has thought of it. Piezo isn’t generally very well regarded outside of instrument contact pickup applications. Maybe it could turn out to be a thing.

a history of recording through 1950

Courtesy the AHRC Research Centre for the History and Analysis of Recorded Music, enjoy a lovely history of recording through 1950. Lots of sample recordings you can listen to, including essentially-hifi recordings made live on 78s towards the end of that technology cycle. (Did you know a 78rpm live-recording shellac disc could record 14khz tones? Neither did I. That’s about where FM radio tops out, for comparison purposes. SURPRISE)

There are a couple of illustrative mp3s showing the difference between purely-mechanical recording and “electronic” recording – the move from acoustic horns to microphones, basically. Still no tape or ability to edit; throughout this entire era it’s still horns-or-live-mics-to-etched-master-disc. But the appearance of electric microphones in 1924 changed everything, and to be able to hear it on from-the-era recordings is just amazing.

(And if you’re seeing this on Livejournal or Dreamwidth, the Korra icon I’m using with this post is basically one of the kinds of microphones they’d’ve been using in the early electric recordings, preserved here. Cool. huh?)

toying with an idea

I’ve got all these “passive” speakers that are part of my PA kit. “Passive” means they are speakers without built-in amplifiers. That was the norm for a very long time, but isn’t so much now.

And I’ve been thinking there’s this super-snazzy mixer I’d like. It’s this, in the 1608 model specifically.

Now, I can use that with external amplifiers. I don’t have to do anything clever. But it’d be nice not to have to haul around as many pieces and leave the amp at home, right?

So I started looking around at amplifier boards I could build myself, with the idea of making my non-powered “passive” speakers into powered “active” speakers, with built-in amps.

And that’s when I discovered “class T” amplifiers, which are fairly new, and are single-board units like this one.

TK2050 single-transistor amp board

And it’s like $23, which is crazy. But they’re all priced like that. All the Class T amps are dirt cheap, but commentary on gear boards is actually pretty good, particularly for these 2050-based units.

Does anybody know anything about these personally? Because I’m pretty intrigued.

another new toy: roland sc-55

It’s a Roland SC-55 MIDI Sound Canvas from 1991! I can now make all the noises you heard in any videogame in the 1990s.

Cheese Factor Five, Mr. Worf – let’s see what’s out there.

Okay, that’s an exaggeration, but honestly not much of one. I got it from Ben Deschamps via his internet yard sale, for, as he put it, “a six pack.” XD I also had to fix it after it arrived damaged in shipping – I’m pretty sure the post office punted it here from New York State, given how quickly it arrived and how the left side of the front panel was punched in.

But hey, now I can say I’ve repaired a potentiometer. Not replaced: repaired. I did that because it’s custom and weird and was in three pieces. (Also the metal frame was bent, some parts got disconnected and also bent, a bit of the motherboard broke off but I’m pretty sure that was just a little bit of grounding pin and it’s already grounded. And I fixed all that, so it’s all good.)

Anyway, it’s a Roland, and my A-30 MIDI keyboard is also a Roland, and turns out, they know each other! Such a small world. All those useless buttons suddenly do things!

There is also a thunder and rain setting. This is hilarious, mostly because there’s really only one thunder effect, so I can use it exactly once ever. I have no plans to do so, but don’t push me, I got thunder.

not me. okay, kinda me last night. but not really me.

Honestly, though, while I expected mostly to be using it for things easy to get right (bells, chimes, simple pipes, synthy-effects, etc), this is 1990s pro gear. The strings and horns, while definitely cheesy, are much less so than what you find in, say, Garage Band today. With the right tweaking and careful, careful playing – it respects key velocity, aftertouch, all those cool tweaks on my keyboard – I might be able to use more parts of it than I expected, maybe even for the swing jazz version of Lisdoonvarna. That’d be awesome.

well that was unexpectedly easy: bongo drum mic stand mount

I’m working on Fake Drumkit part for Song for a Free Court/Anarchy Now, and it needed more real drums, so I got out…

Oh, right, it’s been a while since I’ve talked about Fake Drumkit. So the musical shtick behind the band – as opposed to the political/theme idea – is, “what if a bunch of elves heard metal and thought WE HAVE TO DO THIS” and used what they had.

Since that includes a drumkit, I make what I call Fake Drumkit. It’s made of real drums like bodhran and djembe and bongo and wood block and metal and glass, and fake drums like big sampled bass taiko or at least things which sound kind of like taiko. Anarchy Now also has three tuned glass cymbals. It’s gonna be awesome. n/

Anyway, I have a few drums recorded (and all those glass cymbals), but it needs more. And the bongos sound right so far. Not as bongos – I don’t play them as bongos, don’t expect that – but as midrange drums.

But I don’t have a stand, which makes them a pain to mic. So I drilled a hole in the little plastic bridge that holds the two bongo drums together, and epoxyed down one of those metal threaded rings that are on every mic stand ever and I don’t know why.

Anybody know what these are supposed to be for? They’re no good at anchoring mic clips, so that can’t be it.

I clamped it down with wax paper and tape, to keep the epoxy from sticking to the wrong things (like the clamp), and let it sit until this evening. Then I tried it tonight.

I’m holding the mic stand up, to be safe, but I didn’t need to.

Hey, it even looks kind of intentional:

Lots of room for underneath microphones

I’m a little worried about leverage on heavier strikes, but so far, so good.

Fake Drumkit is a lot of work, but I like it when it comes together. Wait’ll you hear the track for Something’s Coming. It’s not half as complex as this, but it’s totally bombastic – kind of 80s hair metal, really. BOOM BOOM BOOM awesome XD

eta: This one didn’t last. Here’s the new, still low-cost, and much stronger version I made later.

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