Serious FX1 Audio Problem (mic amplification)
 

Greetings everyone.
Recently I decided to upgrade my FX1's audio capabilities with a Beachtek DXA-6 and an AT897. Today both products came in the same box from B&H and I started to play. They seem to work great together and at first I was very pleased.

However, after doing some recording and trying various things, I noticed a problem with my camera. There was a lot of hiss coming from it. To test, I turned off the beachtek and unplugged the mic. With the manual audio control set to 8 or 10 (highest) there was still a lot of noise - not silent like you might expect. Thinking it might be the beachtek, I unplugged it and plugged in a 1/8" mini plug with nothing on the other end (a non-feed). The noise was the same, and the levels were crawling up two or three bars simply because of this static.

Then I discovered the disturbing part: Whenever I bumped the camera, the levels would shoot up and I could actually hear the sound through the camera body in my headphones... How can you get levels without a microphone attached? After further testing, I realized, I could tap the body anywhere and get about the same amount of noise even at volume level 5 (it records to tape and was very audible in playback). I am absolutely sure no mic was working (including the on-camera one). The camera body itself was picking up the rattle of when you touched it...

Am I the only one who has had this problem with the FX1? Either my camera is messed up or the FX1 has some serious other issues. I was able to get much better results by selecing "Line" in rather than "EXT. Mic" in the audio options and using an external amplifier (e.g. voice recorder) to amplify the signal. In this method there was no "self noise" from the camera body and no extra hiss even at volume 10. The only drawback is that I don't have any realistic way of amping the signal prior to putting it in the camera.

What are your thoughts on this? Is it generally better to have the mic signal amplified before sending it to the camera, or has my camera's amplifying powers turned nasty?

Thanks!
-Chad

Mine is dead silent. When I hook up my Evo2 wireless it's perfect. Get your camera checked.

The MIC amp is very noisy on my FX1, although it doesn't transfer handling noise. The EXT in is dead quiet in LINE mode. I'm thinking about a Beachtek DXA 10 but you can't screw it under the camera.

Ben, try a jimmybox attached to bottom of camera, the beachtec should fit.
www.jimmybox.com

I've noticed the same thing and couldn't figure out what to make of it. If other users don't have this problem (as indicated in another post), maybe the suggestion to get a service check from Sony is a good idea.

Called Sony today to talk about it. It took a while to explain the situation, but the guy eventually said that I should send it for repair. The camera is still covered for parts, but service is going to cost $216. I'm wondering if I should just return the DXA-6 and get the DXA-8 (which does preamping) and use the "Line" level input on my camera... It would cost about $80 less, but force me to always use the Beachtek with any mic I might want to use.

Is there really any advantage to having preamps somewhere off-camera? (Assuming you have a functional camera?)

Disregard that last question. I started a new thread here:
http://www.dvinfo.net/conf/showthrea...336#post369336

I just wanted to add that I tested the AT897 with my GL2 and was startled by how much better it sounded aside from the reduction in hiss. It was a deeper, richer sound (much more low tones). I've decided to repair my defective FX1 because it's definitely got some things wrong with it, which have probably been wrong for a while.

It's amazing how spending >$500 on audio gear will quickly sensitize your ears to new things...

-Chad