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I'm recording through my bluebird blue condenser microphone connected to my M-Audio M-Track Interface that is then obviously connected to my laptop through USB. I find that when I listen to the mic through the direct option the sound is crystal clear, but when I switch to the USB there is a consistent crackling noise. I tried adjusting the gain to make the sound as minimal as possible, but even with zero gain the crackling persisted. It persists to the point that it affects my recordings and make them unusable. At first I though it could be the converter piece that allows me to plugin my headphones to the interface, but problem persisted even with purchase and implementation of a new one. Then I figured it had to be the mic cords (I had gotten them free with a 2 pack of stands from musicians friend.) So I went to my friends to test out a mic cable he knew worked well. I recorded myself talking and the crackling noise had ceased. I then listened a couple times to make sure it was not there. I thought I had solved the problem and my friend let me borrow a couple mic cables, but after I had gotten home I tried testing out recording again and the crackling noise returned! I am very upset and baffled by this occurrence so any help you have would be of assistance. Also my bluebird mic and interface are both brand new and should be working flawlessly. I've heard that if I live near radio towers that can cause interference as well as wifi and other signals, is there validity to this?

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Josh Conley Fri, 04/11/2014 - 04:14

usually you want as close to zero latency as you can get when recording vox, but your computer may not be fast enough, so turn that up until it stops.

also, and im talking over my own head but i have heard the nerds talking about shared irq's happening via usb. which i believe is your computer sharing the processing of some usb ports with each other and/or other functions. there is a way to check and then hopefully pick one that is on its own.

RemyRAD Fri, 04/11/2014 - 10:42

Most folks don't have a dedicated computer for their musical purposes. It's a laptop/desktop, succotash, of being used for all your computer needs. Which also means you likely have dozens of other applications, all running in the background. It keeps making your audio recordings hick-up. Every other beat and second. Solution?

There are specific ways to configure a computer, to be used for audio purposes, flawlessly. Unfortunately, some of these settings can leave your computer open to cyber attacks. Which is why it's good to have a dedicated machine/computer, for your music recording and engineering purposes. That doesn't go onto the Internet, daily, if at all.

So it will be stuff like virus scanners, Mal ware scanners, Trojan scanners. It'll be preprogrammed computer housekeeping processes like, auto defrag, auto virus scanning, constant contact back and forth with some other online service? Latest headlines, current weather, current stocks, all that stuff, it needs to be disabled.

A computer needs full-time attention when doing audio. Computers have ADD, like me. It should only be concentrating on one thing at a time. And especially if you're using any kind of real-time effects that put a greater load onto the CPU and loaded memory capabilities. These days, I'm running 16 gigs of RAM, in comparison to my 2 gigs that my previous computer maxed out on. And I've got 4 discrete cores, running as 8 hyper threaded cores, with a 64-bit operating system, instead of a pseudo-early core duo running a 32-bit operating system. Which was slamming better than this brand-new hunk of junk, Windows 8/8.1 abortion with all of its BS, blah blah, improvements, which ain't. In this new HP laptop I just got last year, can run nothing but Windows 8. Which means, it was fraudulently misrepresented as a laptop computer when it was nothing more than a touch sensitive tablet, without a touch sensitive screen. That's not a computer. That's a tablet that can only run a single operating system. Most computers can run more than a single operating system. Your mileage may vary? HP told me I could load Windows 7 on this Envy, DV 7-7292 , when I purchased it. I actually had to spend an additional $150 for Windows 7 on this Windows 8 machine. Only to find out that there were no drivers made for the machine, for its internal items, to run under Windows 7. And Windows 8 really only plays well, with itself. Just like Vista did. No one else likes this bastard child nor wants to support it. Kind of like Windows XP " Media Center Edition ", which had nothing to do with running any professional Media Software like ProTools or Avid Media Composer, which it wouldn't, run. Or much of anything else for that matter.

Steve Jobs is dead and it seems little known by others that Microsoft purchased a 49% share of Apple, not so terribly many years ago. What's that tell ya? Can you say monopoly? I will. It is. So either purchase a Macintosh with its cartoonlike interface. Or learn how to disable what you need to disable, in Windows? There are plenty of computers set up recommendations here, in the library and elsewhere on the Internet. Some suggestions by the company that makes the audio software's you might already be using? And it's not just about the buffers. It's about punching in MS config, from the start menu, " run ". Then going to services and startup and disabling everything except for necessary operating system operation. It'll then tell you you started the computer up with a custom setting. To which you will say okay. Then get to work. Enjoying a more responsive and smoother computer. No more hiccups, voilà!

It could be the pollen?
Mx. Remy Ann David

WinnipegSoundGuy Mon, 04/14/2014 - 22:43

This happened to me as well my friend and after trouble shooting 20-30 different possibilities I gave up and forked out $129.00 for a

I had tested my wall A/C before installing and it was running between 124 A/C to 126 A/C - The A/C surprisingly (to me) dropped to between 118 A/C and 121 A/C - 90 % or more of the crackle was instantly cleared. I am not good with electrical but am going to assume those extra volts contained dirty power. If you have a conditioner, this won't apply to you but if not - You may want to consider the purchase.

Post Notes - This unit is supposed to help with EMF and RF signals (y) (Those Towers you mentioned) Who knows until You give it a shot. Good to have one any ways in my opinion.

Just a thought, good Luck. It amazed me what it did for my lap top / mixer / monitor situation. Cheers !!

WinnipegSoundGuy Tue, 04/15/2014 - 14:16

dvdhawk, post: 413776, member: 36047 wrote: What method did you use to measure the voltage, when you got the 124 - 126v results? Just putting the probes from a volt-meter into the wall socket will give you an inaccurate reading (on the high side). You need to have some load on the line voltage to get an accurate reading.

Yeah, but I had no other way of testing for "surges" which were sometimes only occurring 3-4 hours apart. As my studio is an another room in the apartment, I just let the music play and plugged the DMM into an extension cord to run to the living room, sitting in front of me to hopefully catch a variation in readings to narrow it down some more. Not the best way I am sure but after 20 or so other trouble shooting options didn't fix anything I was running out of options. It did show me that when these "Crackles" happened, there were no changes on the DMM for what that's worth.

Still don't know if it was dirty power as it might have cleaned up EMF or RF signals I am unaware of and that part may always be a mystery I guess my friend?

Either way, the conditioner (without surge protection working as it came without the surge protection indicator light off) I might add has cleaned up something dramatically.

After weeks of troubles shooting this, I would LOVE to know "exactly" what the issue was but am not sure I will ever get that answer now?

Cheers dvdhawk !!

rmburrow Sat, 05/10/2014 - 08:47

Power conditioning in a apartment building is mandatory. Depending on the number of units, the incoming power may be three wire 230-250 volt single phase. Large buildings typically have incoming 208 volt "Y" three phase power. The HVAC and heavy building loads are typically run off the incoming three phase power, and AC wall power for the units typically is taken from a phase to ground or off a transformer supplying power to individual units.

Any "hash", voltage spikes, etc. generated from the HVAC or other heavy building loads will be reflected into units connected across that power leg. You will need a power conditioner or filter to get rid of the artifacts. Ebtech's "Hum-X" is a plug in filter good for 6 amps at standard 120 volt AC power.

Dvdhawk is correct about depending on a DMM to measure AC line voltage. The typical DMM is not amet true RMS AC voltmeter. I have two of the old RCA power line monitors (made by VIZ Mfg. Co. out of Phila.) across each leg of AC. The RCA power line monitor is a true RMS instrument. Another good item for the goodie bag is one of those plug in AC testers. They cost around $10 but anyone doing location work should have one...these will find floating grounds, miswired outlets, etc. by looking at the pattern of the lit indicator bulbs.

paulears Sat, 05/10/2014 - 14:54

dvdhawk, post: 413776, member: 36047 wrote: What method did you use to measure the voltage, when you got the 124 - 126v results? Just putting the probes from a volt-meter into the wall socket will give you an inaccurate reading (on the high side). You need to have some load on the line voltage to get an accurate reading.

If adding a load drops your supply voltage, then unless it's a really big load, as in a high percentage of your total available power, something is wrong. Modern electronic voltmeters measure the voltage to useful accuracy. Any load changes that could cause volt drop will already be on the line - in other rooms of your house. Volt drop from room to room if you detect anything other than tiny amounts indicates fault conditions - and is the opposite of what you suggest. If you have voltage issues, the electricity supplier put a recorder on your supply and like your voltmeter it will have no impact itself on the terminal voltage - which is, after all, what your equipment is fed with.

If you have dirty power, it's dirty. It's not just in the last few volts. Dirty mains power can cause all sorts of issues, but the voltage thing is a red herring. Most devices now are happy with voltages from 110 or so right up to 240V - they don't care and most are switch mode designs, which as they drop the voltage down to low voltage for the electronics, the actual voltage at the outlet doesn't matter.

Dirty power does cause problems, but I'd side with the idea of processor buffer issues with latency too low. Clicks pops crackles and all sorts get caused by this issue. Power conditioners help with dirty power, but before spending lots of money, double check. Depending on your operating system, you may be able to check on processor activity, in terms of how hard it's working.

The types of measurement system used in true RMS metering systems are able to measure the voltage very accurately. A DMM by it's design nature can have errors, but for the purposes of simply seeing what your power outlet voltages are (for the reasons in this topic) they're perfectly good enough. Just for fun, I've just checked mine on two DMMs and the two meters tell me that it is currently 237 on my cheapo meter, and 237.4 on my Fluke 115. (and 49.7Hz)

Turning off all my studio equipment made no difference to the voltage.

dvdhawk Wed, 05/14/2014 - 13:46

Hi Paul, I agree, even the cheapest multi-meter will get you close enough for rock n roll. My question / comment was to reassure the OP that what he was seeing was perfectly normal. I wasn't the least bit surprised he got a reading of 124V from the wall before, and 118V with his new Furman plugged in. (which I assure you has no voltage-regulation. Filtering=Yes, Regulation=No)

For the majority of users, with an assortment of typical meters, the false (slightly-high) reading would be completely normal and no cause for concern. We may need someone with the official EE degree (Boswell, Mr. Burrow, or MrEase perhaps) to give a proper technical explanation of voltage-drop / or set me straight on my explanation. All I know from my admittedly limited schooling and decades of hands-on work, is that unless current is flowing, you don't get an accurate voltage reading. If there's no load, it's not a circuit, and (typical) meters invariably tend to read higher than the real-world useable voltage.

Also not surprisingly, factoring into your voltage readings are; wire length & wire gauge, (both forms of resistance) and the amount of the load (current) - which applies to any circuit; including, on the larger scale, from the high-voltage utility transformer on in. As you know, Mr. Ohm will have it no other way.

I'd be curious to know if A) your studio equipment is 100% the only thing on a dedicated circuit from the electrical panel, and if B) you merely switched the equipment off - or pulled the plug from the wall. Many modern devices go to stand-by when powered off and are still using electricity and presenting a load.

paulears Wed, 05/14/2014 - 14:59

Re: the studio kit - 4m of 10mm2 from a 20A isolator on a spur to the consumer unit with a 16A MCB - so one switch kills everything except the computers. Normally we use ring mains here - loads of 13A outlets on a ring protected with a 32A MCB (wired with 2.5mm2 cable) - but in the studio the main rack gets the direct supply and then acts as a hub for everything to be plugged into.

As an aside - in the UK we were always 240V/50Hz, in mainland Europe it was always 220V/50Hz. Now we are 'electrically harmonised' - so we describe it as 230V/50Hz everywhere in Europe. We do all calculations based on 230V (with three phase sitting at 400V) but the spec was carefully written to have a plus/minus figure, which rather craftily means we stay at 240, and the rest at 220. The only time is really causes issues is with lighting where a real 240V lamp is a lower colour temperature in say, Holland, while a 220V lamp over runs on our 240V supply. As they're trying to get rid of tungsten, nobody gets that cross, with the public thinking the lower lamp life is normal, making green energy look better - say me the cynic!

In fact, modern kit is truly international. Voltage switches which often caused US kit imported to blow up are quite rare now - equipment is happy on almost anything. Even if you are in an installation with too narrow cross section and very long runs, the extra volt drop with heavy loads rarely causes grief nowadays.

We do get lots of hum issues, which are usually the result of the neutral creeping away from the ground putting a few volts on the ground, that find their way into the kit. With dodgy equipment and 2 wire mains circuits, our potential 230V across the live to neutral or ground is quite dangerous compared to the US version, so needs a bit more respect.

As a result, we try to scare people with a standardised (almost) test for equipment. Many places insist on kit being tested before plug in, but poor grounds and too high resistance are common reasons for failure.