#512516 - 04/18/04 12:22 AM
System Noise Is The Enemy: How do we bring it down???
|
gaotu
Senior Member
Registered: 01/10/04
Posts: 211
Loc: Indianapolis
|
Offline
|
|
Here's several questions rolled into one post, that I must ask because high-end hiss is ruining my tracks:
First off, can you really cut back the noise if you convert from unbalanced signals (like those from a keyboard) to balanced? If so... won't most pre-amps do that? And if so... should one buy an 8-channel unbalanced-to-balanced converter? What about a hum-eliminator? Don't most mixers convert an unbalanced signal to a balanced somewhere in the chain making a converter prior to that unnecessary - or am I wrong about that?
Next: My mixer, suppose to be a recording mixer from Vestax (known for great DJ mixers), has only a two-prong cord. Does the 3rd, ground prong help with system noise. My BBE Sonic Maximizer (unbalanced version) also has only a two-prong cord. And with all this, does it help all that much to have a "power-cleaning" surge protector with an RFI filter? Must say that it doesn't seem to help much for me. My main culprit is my low-end effects processor with a wall-wart. Are wall-warts notorious for causing noise interference, or is it possibly just my effects processor?
Lastly and Mostly: Is there really ever an advantage to keeping a signal unbalanced or should conversion be made ASAP?
Any other tips on noise cancellation would be great. My system is all outboard - no computers - within those constraints, what can be done?
|
|
Top
|
|
|
|
#512517 - 04/18/04 12:40 AM
Re: System Noise Is The Enemy: How do we bring it down???
|
Bill@Welcome Home Studios
MP Hall of Fame Member
Registered: 08/23/03
Posts: 7343
|
Online
|
|
In my opinion, there are two issues at stake here... quality of the gear, and unity gain.
If Vestax is known for great DJ mixers, that has happened in the last few years. When I was working at a place with a DJ supply division, Vestax was the cheap stuff that they sold to guys who didn't want to spend any money but wanted every feature under the sun. Nothing wrong with that, but it was considered to be definitely entry level by their sales people.
Personal opinion, but I would never put anything that I've recorded through a sonic maximizer.
Another thing to consider is what comes out of a keyboard... if you are trying to push those poor circuits into giving you full scale digital output, you are probably generating the noise right there.
Maybe back the gains down? Look at -18 dBFS as a zero point?
Bill
_________________________
"...it's easier than hitting the kids, and almost as much fun..."
|
|
Top
|
|
|
|
|
#512518 - 04/18/04 12:47 AM
Re: System Noise Is The Enemy: How do we bring it down???
|
Philip O'Keefe
10k Club
Registered: 12/17/00
Posts: 17674
Loc: Riverside,CA,UNITED STATES
|
|
Offline
|
|
It's probaly not your wall wart power supply. Chances are, it's the quality of your effects unit, or possibly gain staging issues or a combo of the two. You could also be running into grounding and / or ground loop issues. You might want to do a search of these forums on those topics for some suggestions on improving things.
|
|
Top
|
|
|
|
|
#512519 - 04/18/04 05:42 AM
Re: System Noise Is The Enemy: How do we bring it down???
|
RobyG
Member
Registered: 04/18/04
Posts: 3
|
|
Offline
|
|
It's true, you can run into some pretty severe problems with grounding.
Wall warts usually generate a high level of EMI that can cause some serious noises IF your cables are in close proximity, especially with those unbalanced cables. Watch placement of cables. Never run power and audio parallel.
Another issue may be just choice of gear. I remember back in '92 having a Lexicon LXP-15 that I paid $1500CDN for and thinking it was noisy. After talking with other studio owners I found they had similar opinions. So gear selection may be an issue....but you can easily verify your gear by moving it to another site to eliminate any local concerns. Or check out harmonycentral.com for reviews.
You may want to consider having a professional come in and inspect your gear wiring, and even your house wiring.
|
|
Top
|
|
|
|
|
#512520 - 04/18/04 02:45 PM
Re: System Noise Is The Enemy: How do we bring it down???
|
Cameron Reddy
Member
Registered: 03/26/04
Posts: 1
Loc: Ann Arbor, MI
|
|
Offline
|
|
Hi,
I'm no expert but I can make a couple of comments that might help.
The first is a question. Is you hiss recorded or possibly CREATED during the playback by poor quality amplifiers which are notorious for hiss?
From a purist audio standpoint, and as I understand it, audio is created unbalanced and so keeping it that way is best. However, if you have to run the signal more than a couple of feet or anywhere near a power line or other source of electronic, magnetic, or even physical (like vibrations) interference you need a balanced signal to have any chance of surviving intact. Many very high end pieces of gear (my Forssell CS-1 as an example) come with unbalanced outputs to retain sonic purity. Put a TRANSFORMER (look at the word) in line to create a balanced signal and you transform the signal. On this issue, be aware that there is such a thing as impedance balanced and transformer balanced. Only the latter is a true balanced signal. Many pieces of equipment say "balanced" but are in fact only impedance balanced. Don't ask me what impedance balanced is because I frankly don't understand it; I just know that it is not truly balanced.
Lastly, to be honest, your equipment may not be of a quality to amplify signals without pretty audible hiss. My guess it your best option is to work on gain staging from piece to piece and get the hiss as low as possible.
Hope this helps.
_________________________
Cameron Reddy
|
|
Top
|
|
|
|
#512521 - 04/18/04 04:30 PM
Re: System Noise Is The Enemy: How do we bring it down???
|
gaotu
Senior Member
Registered: 01/10/04
Posts: 211
Loc: Indianapolis
|
|
Offline
|
|
Thanks for the input thus far.
* One side comment though (from an X-DJ): Vestax is and has been a highly esteemed (by world-famous/skilled DJs) manufacturer of rather expensive mixers. Until Allen and Heath put out their DJ stuff in the staes Vestax was at the top of the heap. Rane is nice, but they were always behind the curve as far a giving a DJ creative freedoms. Anyway...
what comes out of a keyboard... if you are trying to push those poor circuits into giving you full scale digital output, you are probably generating the noise right there
As far as the monitoring concerns go, I do believe I may be having some problems there because once on CD, I don't hear the hiss nearly as much in other playback systems. I will be switching to balanced connections to my amplifier ASAP.
Gain Staging: I DON'T KNOW ABOUT THIS CONCEPT - HELP!!! What is this all about. I hear reference all the time, but somehow I've overlooked it.
|
|
Top
|
|
|
|
|
#512522 - 04/18/04 06:02 PM
Re: System Noise Is The Enemy: How do we bring it down???
|
Bill@Welcome Home Studios
MP Hall of Fame Member
Registered: 08/23/03
Posts: 7343
|
|
Online
|
|
My MIDI stuff is older, 16 bit stuff; but if I push the gains, I also get a great deal of noise with the signal.
Bill
_________________________
"...it's easier than hitting the kids, and almost as much fun..."
|
|
Top
|
|
|
|
|
|
|
