Speeker Hiss

zac850

Well-Known Member
Ok, heres the problem:
I'm running a mic, with 2 speekers in a small space. I have two speeker cables, and one mic cable running somewhat near each other, but when they cross its at a 90 degree angle. The problem is, I am still getting speeker hiss...
My question: How far away do speeker cables need to be from a mic cable, and how long do they need to be running parallel to each other for the hiss to be bad?
Its not bad now, just a hiss that can be heard while the room is quiet...

Please get back to me ASAP, the shows are tommorrow and I just became aware of it today....

Thanks, Zac
 
zac850 said:
Ok, heres the problem:
I'm running a mic, with 2 speekers in a small space. I have two speeker cables, and one mic cable running somewhat near each other, but when they cross its at a 90 degree angle. The problem is, I am still getting speeker hiss...
My question: How far away do speeker cables need to be from a mic cable, and how long do they need to be running parallel to each other for the hiss to be bad?
Its not bad now, just a hiss that can be heard while the room is quiet...

Please get back to me ASAP, the shows are tommorrow and I just became aware of it today....

Thanks, Zac

Hiya,
When you say speaker hiss I am guessing you mean that it is a sound with no tone, no static, no real anything except a "presence" to let you know the system is on, and that is present when the system is turned on and the room is empty and all faders / etc are down, correct? Kinda like a "white noise" sound?? Kinda like "tape hiss" when you play a tape that has nothing recorded on it??
Well if such is the case, I have to tell ya that its not any kind of interference between the cables. No such thing really between mic and speaker cables interfereing between each other. Only need to cross AC cables and mic cables at 90 degree angles really--and thats only when it comes to snakes and high voltage...but thats another story. But back to your hiss problem---fact is its not any kind of thing you can control really-its called "noise"...and the origin of this noise has to do with the electronics you are running. Every piece of equipment in your signal path can add "noise" to a system..and that noise is additive in a system--it can compound and become louder... There is no such thing as a completely noiseless sound system--but you can get systems and gear that greatly reduce the noise to inaudible levels so you do not have that hiss. Hiss can come from playback gear, amps, consoles, mic pre-amps, EQs--almost anything in the signal path. Now a channel does NOT need to be turned up to hear the hiss--but it can make it more noticable if the source of the hiss is comeing from your console or channel. Cheaper components in a sound system add "noise" to a signal or a system, and its the reason why many sound components cost so much is to reduce that hiss..its like a "presence" that lets you know the sound system is turned on. Now--you can trace down the hiss to find the culprit that is giving you the most noise... To do this you want to start at the Mic and unplug it--hiss stil there? if so then move on to the next thing--the Channel strip--is your GAIN or preamp cranked up all the way--if so turn it down as much as possible, does this reduce the hiss? If you crank it up with NO MIC attached to teh channel does the hiss increase? Next move to the channel EQ--take about 8k and dial it UP and then OUT and see how that effects your hiss.. Next is your MAINS level--does the hiss go away when you turn the mains faders down? If not--next is to try any outboard gear you have after the console...such as EQ''s or crossovers...do the same--with no mic attached just see if the hiss increases or decreases with manipulation of the gear (boost and cut)...lastly--turn the gain on the AMPS all the way down--the hiss should then go away and you have your culprit. Very rarely will you be able to turn the amp gains down and still have hiss..(that would be something more complex to deal with).

A good trick to solve some of the hiss on an amp is to turn the amp gains from full open to about 3/4 way open (provided you are not underpowering your speakers even more). Occasionally too much gain on an amp, a channel or pre-amp can be a cause in a normally quiet sound system. Sometimes folks may have a gain turned up real high on a channel and not even know it cause nothing is plugged into that channel--but that noisy pre-amp will make thathiss seem larger then life. There is always going to be some sort of electrical "noise" or hiss in most sound systems...until you replace most of the culprit gear that adds noise with gear that is sonically quieter and electronically cleaner in processing (a.k.a more expensive).

Sometimes--if you get hiss on one channel of a console but not on others, you could have a failing pre-amp or a bad potentometer that may need cleaning...sometimes a simple repair or cleaning can lessen the problem. If you get hiss only on one channel of an amp and not the other--its a sign your amp could be having issues--try cleaning it out with air and see if that helps. If not--put a amp on your wishlist for upgrade.. Fortunately when most rooms fill up with ambiant noise it drowns out the hiss--which is a small part of the "siganl to noise" ratio of things in sound systems and sound reinforcement.

Failing being able to solve the problem without buying new gear--you can always tell anyone who complains that you are "letting the air out of the sound system to allow for more dynamic range when the program begins--cause it helps to reduce feedback"...and most idiots will look at you and go--"oh of course.."...and you can just laugh at them for believing you and thinking they understand all that silly sound gear stuff. ;)

I love telling people I'm letting the air out of a sound system...if I could have done something about the hiss I WOULD have...but short of soldering up a new system I can't....idiots!! hehehehe...

-wolf
 
ok, so from what I understand, you are telling me that there is nothing that I can do for it, short of buying a new system or spending hours on it

the problem is the show is starting in 49 minuits, nope, now 48 minuits so I don't have enough time to do a big overhall...

thanks,
Zac
 
zac850 said:
ok, so from what I understand, you are telling me that there is nothing that I can do for it, short of buying a new system or spending hours on it

the problem is the show is starting in 49 minuits, nope, now 48 minuits so I don't have enough time to do a big overhall...

thanks,
Zac

yup....system noise--all you can do is diagnose to find the worse cuplrit in your system and make that one a priority to replace when you can. Sorry..

wolf
 
zac850 said:
ok, so from what I understand, you are telling me that there is nothing that I can do for it, short of buying a new system or spending hours on it

the problem is the show is starting in 49 minuits, nope, now 48 minuits so I don't have enough time to do a big overhall...

thanks,
Zac

yup....system noise--all you can do is diagnose to find the worse cuplrit in your system and make that one a priority to replace when you can. Sorry..

wolf
 
Inaki2 said:
By the way Wolf, fantastic explanation!


;) thank ya sir... Figured I should be descriptive cause a lot of folks don't know about what "noise" is in a system and how it comes from certain things...

-wolf
 
Yup I know, I've had my share of discussions. Last one funny as actually related to SPL, the woman who cleans the ladies bathroom in the club argued wit me that the SPL in there was 160dB........ 8)
 
Inaki2 said:
Yup I know, I've had my share of discussions. Last one funny as actually related to SPL, the woman who cleans the ladies bathroom in the club argued wit me that the SPL in there was 160dB........ 8)

Or the time that our Teacher TD thought that Feedback was caused by an amp under too much load.
*Covers face in hands...*
 
I agree, great description of hiss!

I had a show once where a hiss started half way through, and it was a BIG hiss.... turned out too be a stuffed lead and DI box... wasnt happy, was a nice DI box when it worked.... long story but the DI was on the main amp.... again, very long story lol

god ive done some weird things at work *shakes head*
 
Well if you're looking for stupid questionsd and assertions, I have a ton of them. Ranging from "I've done parties with 1watt" (yes, some moron actually aid that to me) all the way to "Macki is the most professional equipment out there" (some guy triying to impress the oladies, he didn'tlike it when I said "So wat about Midas?" "Whats that?")
 

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