Hissing - How To Stop It

[spinner 0]

I have 2 sound systems - one is an HK Soundhouse One, the other uses FBT MaxX4 tops plus bass bins and a separate amp.

 

My main console case contains an Allen & Heath XoneS2 mixer. Whichever system I use I get "hiss" through the speakers. Obviously this is more apparent close up with no audio going through and less so in a cowded function room with all the general surrounding noise, but it's still annoying.

 

I wondered if this might be caused by the cheapo RCA leads that came with my hard drive controller and CD decks.

 

However, at one time, using a different set-up, I used high quality hi-fi interconnects and got a "hum" through my system which disappeared when I swapped to cheapo RCA leads!!

 

Any ideas please?

[Welsh Audio Man 21 0]

I have 2 sound systems - one is an HK Soundhouse One, the other uses FBT MaxX4 tops plus bass bins and a separate amp.

 

My main console case contains an Allen & Heath XoneS2 mixer. Whichever system I use I get "hiss" through the speakers. Obviously this is more apparent close up with no audio going through and less so in a cowded function room with all the general surrounding noise, but it's still annoying.

 

I wondered if this might be caused by the cheapo RCA leads that came with my hard drive controller and CD decks.

 

However, at one time, using a different set-up, I used high quality hi-fi interconnects and got a "hum" through my system which disappeared when I swapped to cheapo RCA leads!!

 

Any ideas please?

 

I know this doesn't answer your question, but I have never seen the point in using high quality gold plated blah blah hifi interconnects unless your mixer and playback have the same quality connections (generally they are just tin sockets).

 

I'm not sure how you have your mixer set up, but have you tried dropping your gain a little? Does it happen, no matter what channels on the mixer you use. Does it happen when channels are down but master is up only?

 

I know they are simple questions, but just trying to suss out where the problem is (ie. prior to entering mixer, particular item etc...)

[gadget 0]

Do you get hiss when nothing is connected to either amp input, or does it only happen when the mixer is connected.

 

Does it happen when everythign is connected, yet the mixer is powered off (no output from the mixer) ?

 

Not potentially some sort of earth loop?

 

I've had hi-quality hi-fi connectos before now - and because they were a lot stiffer, the ground/signal lines used to break much more easily than normal cheaper cables :/

 

Cheers,

 

David

[spinner 0]

I know this doesn't answer your question, but I have never seen the point in using high quality gold plated blah blah hifi interconnects unless your mixer and playback have the same quality connections (generally they are just tin sockets).

 

In that instance I was using a mixer that had goldplated inputs.

 

I'm not sure how you have your mixer set up, but have you tried dropping your gain a little? Does it happen, no matter what channels on the mixer you use. Does it happen when channels are down but master is up only?

 

 

If the master gain is dropped the hiss drops with it.

Edited November 26, 2010 by spinner

[gadget 0]

If the master gain is dropped the hiss drops with it.

 

on the mixer? at 0dB there shouldn't be much hiss coming out of the mixer - if everything else is disconnected apart from the mixer and speakers, do you still get a hiss?

 

What's the gain set to on the speakers?

 

David

[spinner 0]

Do you get hiss when nothing is connected to either amp input, or does it only happen when the mixer is connected.

 

The latter

 

Does it happen when everythign is connected, yet the mixer is powered off (no output from the mixer) ?

 

No

 

 

Not potentially some sort of earth loop?

 

 

I doubt it. That would produce a hum, not a hiss.

 

 

 

Of course it could be that the Xone S2 is a hissy mixer. I have a Numark PPD9000 too and that has a reputation for hissing.

[gadget 0]

Of course it could be that the Xone S2 is a hissy mixer. I have a Numark PPD9000 too and that has a reputation for hissing.

 

My mixer also hisses on the output too.. So I turn the gains down on the Amps a bit to compensate. I've heard the hissing after finishing a gig only a couple of times when the amp gains were right up, and not turning down the master fader straight away....

 

It's quite poor that such an expensive mixer and brand such as Xone, hisses though

Edited November 26, 2010 by gadget

[Robster 0]

magnetic fields can induce hum so any transformers , power packs ,other coiled up wires but your experiencing hiss which i found is normally from RF interference , quality RCA leads can help ..again move about any items that are sources of potential RF interference.

 

I would do the standard unplug everything and plug one thing at a time and listen at each step to try to identify the culprit/s it may be a combo of things (i am guessing you have already done all of this as i know you know your stuff)

 

The other source i have found in experience is when a item of equipment has a fault

 

 

As for gold connections they dont tarnish thats why gold is easy to find it stays shinny and doesnt oxidise hence it makes for a better electrical connection also cables with gold ends tend to have better cable (not always) the cable can be ofc occ copper and have far better shielding , what is a con is optical connectors with gold plated tips. Richer sounds are still a good place to go for cheap high quality 2 rca to 2 rca leads. but pretty useless for any other sort of leads.

 

as both systems hiss and the common point both use is your console i would look there and also check your gain structure

Edited November 26, 2010 by Robster

[Welsh Audio Man 21 0]

As for gold connections they dont tarnish thats why gold is easy to find it stays shinny and doesnt oxidise hence it makes for a better electrical connection also cables with gold ends tend to have better cable (not always) the cable can be ofc occ copper and have far better shielding , what is a con is optical connectors with gold plated tips. Richer sounds are still a good place to go for cheap high quality 2 rca to 2 rca leads. but pretty useless for any other sort of leads.

 

 

But if your mixer and players are not gold plated connections, doesn't that make it rather pointless as they will tarnish...

[Robster 0]

Its about getting the best signal possible to that point and reducing the items that will "rust" I agree emphasis is often on the connector not the cable but often but not always gold connectors are generally better made and machined although there are many crappy gold leads out there .

 

Ixos , QED and the chord company make some really nice RCA leads that do make a difference to audio for not a lot of money but they are often big thick and not flexible

 

 

[mjmac 0]

But if your mixer and players are not gold plated connections, doesn't that make it rather pointless as they will tarnish...

It goes a littel deeper than just the connection!

 

The resistance in the signal path and distance of the cable make a difference on how much noise is collected along the way... and how the quality of the original signal is effected by the time it gets to the other end. Different metals act differently on sound... some carry low frequencies better others carry high frequesncies better - as they say horses for courses!

 

Pay a resonable amount but dont go mad - or even make the cables yourself, custom lengths etc.. that way you get the length you need and not loads of slack curled up collecting noise!

 

i agree about those gold plated fibre optic cables... alway makes me laugh when some spotty dixons employee tells me to pay huge amounts for nylon cables with gold plated ends! And the gold does what to the signal? lol

Edited November 26, 2010 by mjmac

[spinner 0]

as both systems hiss and the common point both use is your console i would look there and also check your gain structure

 

 

 

I do have some high quality leads that, coincidentally, came from Richer Sounds and I had been intending to try them so that will be the next thing to do.

 

Reducing the gain certainly does reduce the hiss but all analogue mixers will have a certain amount of it and, from my research, I have found that my situation is not uncommon.

 

When I was using Pioneer DJM mixers I didn't get much hiss and the Allen & Heath Xone S2 is in roughly the same price/quality bracket.

[wizard 0]

My pioneer setup gives more hiss than my old cheap Numark system used to, both using the same amp and leads.

[Robster 0]

seems you have it covered spinner and it may be that you are being audiophile critical of your system.. have any clients noticed it or mentioned the hiss ? If not it is nice to see that you care and also that your hearing is still good after years as a DJ , i feel so many young dj's play it too loud for too long that the only hiss they will hear is tinnitus in a few years! lol

[gadget 0]

seems you have it covered spinner and it may be that you are being audiophile critical of your system.. have any clients noticed it or mentioned the hiss ? If not it is nice to see that you care and also that your hearing is still good after years as a DJ , i feel so many young dj's play it too loud for too long that the only hiss they will hear is tinnitus in a few years! lol

 

Past couple of gigs I've been asked to turn it up a notch (thought it was reasonably loud in the first place!). Even over the buffet break too..

[spinner 0]

My pioneer setup gives more hiss than my old cheap Numark system used to, both using the same amp and leads.

 

 

Sounds like I'm probably being overly sensitive about it!

[nrgize 0]

I bought a DI unit. Now I get no hiss or hum through my speakers at all. I have used XLR leads in the connection from my mixer to the DI unit and then straight from the DI unit to my amps. This seems to have done the job for me.

[vokf 0]

Hi Steve,

if your mixer has a separate earth, then connect this via a dedicated cable to the earth pin of the mains.

 

I had minor hiss problems on my NuMark mixer (it was being generated by the mixer), and providing a good earth helps very much.

 

If your playback unit has an earth, this should also be made off (my DDS does not - its powered by an isolated DC adapter)

 

Jason

[Teez 0]

I manage to get rid of my hiss by not turning on the equipment...

 

:joe:

[spinner 0]

Hi Steve,

if your mixer has a separate earth, then connect this via a dedicated cable to the earth pin of the mains.

 

Jason

 

 

The only separate earth connection is that for a turntable. Is that what you mean?

 

I manage to get rid of my hiss by not turning on the equipment...

 

:joe:

 

 

I can do that too.

[Marble 0]

So glad I'm not the only one who finds odd noises coming out of their PA. IT drives me nuts... but

 

One venue makes my speakers produce a slightly louder hum and it used to produce that high pitched whine usually associated with tv's.

One used to create an electical noise (which I can only descibe as similiar to the yellow line in this picture http://forex.eazel.com/wp-content/uploads/...06/zigzag_2.gif ) but that stopped for no reason two months ago

My Flat (providing I don't use a certain plug socket) leaves a tiny tiny hum and a little hiss

One venue changes between the aforementioned yellow line and a hiss or almost silence.

 

In all cases except the flat, I've changed leads, players, mixers, power supplies... and still these odd things happen. (should also add, I've changed speakers as well... I still get strange noises, venue specific but the humm/hiss/buzz will alter)

 

I did find a light I owned, was responsible for very loud hums, and making tv screens flicker... which I thought was impressive for an led, since I thought they didn't use a lot of power... (should add that the light worked fine whenever ever it was on a stand and it would work perfectly in one venue where ever you put it).

 

Did a gig with someone elses PA at the weekend (in a new venue for both of us) and an almighty buzz came from both speakers... they claim (and i don't doubt them) it's never done that anywhere else... and again they had no idea what caused it.

 

No idea what causes any of this... and I am fully aware in the last four years I've become really fussy when it comes to sound. So annoying loud noises to me are barely noticible to others and playing music drowns out any speaker idiosyncrasies ... but would love an explanation... currently my partner and I blame "dirty" electric and ghosts.

 

[Robster 0]

for mains induced problems a device like this is an idea

 

CLICKY

 

 

http://www.lindy.co.uk/lindyshop/pictures/30087xxl.jpg

 

[superstardeejay 0]

You really need to find where the hiss is coming from. This sounds obvious but alot of the suggestions so far are stabs in the dark. No amount of filtering, isolation or earthing will stop a mixer hissing if (for example) it is caused by a noisy output stage.

 

Power up the mixer, no flight case or rack, and one speaker and nothing else connected, see what that does. If the hiss is still there, try the other speaker to eliminate the speaker. If it happens with either speaker, try a different lead. Its a rational process of elimination.

 

Some mixers simply have a high background hiss; those with twiddly effects and those that have a degree of internal digital processing being the worst, for example certain Denon mixers.

Edited November 28, 2010 by superstardeejay

[Dukesy 0]

I did find a light I owned, was responsible for very loud hums, and making tv screens flicker... which I thought was impressive for an led, since I thought they didn't use a lot of power... (should add that the light worked fine whenever ever it was on a stand and it would work perfectly in one venue where ever you put it).

 

Probably had a basic switch mode power supply in it, as opposed to a more conventional linear unit. The problem with cheaper power supply units is that they can cause interference, either through the mains or by RF. It can also be an indication that the power supply is on the way out, usually caused by capacitors leaking or 'drying' out

 

Obviously the smaller / cheaper units become, the fewer components used and corner cutting, leading to similar issues, where sound systems are concerned.

 

For hissing problems, a noise gate can be useful which fits between the line out of the mixer and input to the amplifier, and will cut the signal below a certain (variable) level. This is useful for 'silent' parts of the evening with no sound running, but won't help much during background music etc.

[Marble 0]

Probably had a basic switch mode power supply in it, as opposed to a more conventional linear unit. The problem with cheaper power supply units is that they can cause interference, either through the mains or by RF. It can also be an indication that the power supply is on the way out, usually caused by capacitors leaking or 'drying' out

 

Just to pick your brain (since you have already demonstrated you know far more than me, in just a few sentances) Twas an American dj aggressor, the lovely man who does my pat testing checked everything he could and it all came up fine, so with that in mind is it likely to be a basic switch mode power supply? Or (As i like to think) evidence that every venue in my local area sits on a lay line.