iMic volume/noise issues

[tymime]

Cables arrived, tested the setup, finally recording at a decent volume!
Anybody got any tips on reducing hum?

[kozikowski]

Oh, yes, the ribbon owner.

Another oddity of ribbon microphones is that they're very sensitive to magnetic fields. Can you move the microphone around, turn it and flip it and find a place where it doesn't hum? Mine did that for years and it didn't stop until the Los Angeles Department of Water and Power replaced the power lines, service pole and my house electric service.

No small feat, that. The up side is that they took my 1946 electrical wiring with them when they left. And my hum.

You can get hum if you have a bad connection anywhere. Unplug and replug everything. Wiggle the connections. If you have multiple things plugged into the wall, make sure they're all plugged into the same wall. Not one plugged into the bathroom and one plugged into the living room. In my house, those are different power services and they will hum against each other.

Does your analog/digital adapter get its power from the computer, or from its own little wall plugged power supply? Oddly enough, the wall-wart is much better in this case.

And, of course, the techies will all leap forward with the instructions for using the Noise Removal Tool. Those of us that have tried it know to only use the one in Audacity 1.3. The one in 1.2 is pretty dreadful.

http://audacityteam.org/wiki/index.php? ... se_Removal

Koz

[tymime]

Oh, yes, the ribbon owner.

>_>...

Unfortunately my house is pretty old (from the '40s or '50s) and the wiring is kinda iffy at times. I guess I'm stuck with that, but I'll experiment with the wiggling and such.

The iMic has no power supply of its own, and I'm sure it would say that on Griffin's website if it did.

As for noise removal, the one in Adobe Audition (been running that in VMware these days) is exceptional. I had an old hissy, buzzy cassette copy of a crackly old vinyl record digitized and cleaned up last year, and besides a few pops, it's never sounded so good. One of these days I need to get the original vinyl and digitize that.
It's just that I'd rather not have to remove the hum every time I recorded something, so preventing it from even happening would be ideal.

[steve]

Poor quality leads can cause hum. Also a poor contact somewhere, and being located close to appliances that are electrically noisy. Close proximity to electric motors can cause problems. My parents had a fridge that caused clicks and hums, so my father would switch it off while he was recording and we were not allowed to open the fridge until he had finished recording. They eventually got a new fridge.

[tymime]

Hum is getting worse and no amount of jiggling or replugging is helping.
I'm feeling very disappointed right now. These are expensive, high-quality products here! Is it my cables?

[steve]

Your set up has changed over the course of this discussion. If you could you run through a detailed description of your current set-up we may be able to spot some likely causes.

[kozikowski]

<<<These are expensive, high-quality products here!>>>

Not if you're still using the iMic, it's not. Multiple people with bad experiences have told you to stop doing that.

Koz

[tymime]

Your set up has changed over the course of this discussion. If you could you run through a detailed description of your current set-up we may be able to spot some likely causes.

You should know exactly what my set-up is. I posted it not too long ago, remember? Please try to keep up, guys- I don't know how many times I've had to repeat information already in this thread.

Not if you're still using the iMic, it's not. Multiple people with bad experiences have told you to stop doing that.

Nobody's ever told me to stop using it, and please, go away. I've tolerated your thinly-veiled insults so far, but I've had enough.

Anyway, if the iMic is really so bad at recording from a mic (which, by the way, is not the source of the hum- it's the preamp), would something like a cable with a 6.3mm/1/4" jack on one end and a USB connector on the other work? Does such a thing exist?
Ugh, this wouldn't be so difficult if my Mac actually had a microphone jack.

[steve]

This was your last post regarding your set-up:

------------ START ----------------------

The thing that is confusing me is that on the Electro-Harmonix web page about the 12AY7 mic Pre-amp, there is no mention of a 1/4" input. It says there is a 1/4" output, and XLR output and an XLR input, so without a male XLR to female XLR lead I cannot see how you can connect your microphone to the pre-amp.
http://www.ehx.com/products/12ay7-mic-pre

1/4" output? Well, no wonder it didn't work! I was using that to plug in my mic! I must have forgotten about that. By the time I actually tried recording, I hadn't looked at the website in a while.

I still need to know about that iMic. Mine had two different connectors and a Hi/Lo switch on it. Does yours?

Huh, so iMics do vary. Who knew?
So mine's got 1/8" "in" and "out" sockets, and a Line/Mic switch. It also came with a preamp of sorts for line recording, which has L/R RCA sockets.
------------ END -----------------------

And this is from your previous post:

------------ START ----------------------
Like I said, I tried many different combinations, but none of them worked. I also said before that I have no cable with an XLR on both ends. I have two with a 1/4" jack on end and a female XLR on the other.

If it helps, I also have one with a stereo 1/8" on one end, and L/R RCAs on the other that I plug into the iMic's "preamp" for converting tapes, and a simple one with a stereo 1/8" on both ends that I use to send out my Mac's audio to my good stereo.

How does this sound?: mic > XLR on both ends > preamp > mono 1/4" to 1/8" (like this) > iMic > USB
------------ END -----------------------

Sorry, but I can't see your set-up and I don't really want to be trawling through all 47 posts in this topic to try and guess exactly how it is set up today as if I jump to any incorrect assumptions it is unlikely that I will be able to offer any helpful suggestions.

Try not to be too irritated by Koz, he has a rather "unorthodox" style (read "grumpy") but has a terrific track record for helping hundreds of people solve their Audacity problems, particularly on Macs.

Regarding the iMic - this is definitely a weak point in the set up. The microphone and pre-amp that you have spoken for before both look like fine pieces of equipment, where as the iMic is designed as an inexpensive audio interface for casual users (the prices give a good clue). However, it should still be capable of giving you pretty good quality recordings if everything else is set up correctly.

The fact that you are able to record shows that everything is almost correct, but there is probably some small detail that we are overlooking, and that is why I asked if you could recap on the detail of your set-up. Even things as seemingly trivial as powering your computer through an extension lead, or the exact wiring of your interconnect leads can be important.

[tymime]

How does this sound?: mic > XLR on both ends > preamp > mono 1/4" to 1/8" (like this) > iMic > USB

This right here is my set-up. Believe me, if it had changed, I would have told everyone.

I have no complaints about the iMic so far, because I can say with certainty that what Audacity records is what's coming out of the preamp without any loss in quality.

The fact that you are able to record shows that everything is almost correct, but there is probably some small detail that we are overlooking, and that is why I asked if you could recap on the detail of your set-up. Even things as seemingly trivial as powering your computer through an extension lead, or the exact wiring of your interconnect leads can be important.

All I can think of is that I have an external hard drive with a cooling fan that whirs quietly to itself, but this is several feet away from the preamp- and that the preamp itself has to be plugged into an extension cord to reach the nearest wall socket. Hope that helps!