Speakerplans.com Homepage
Forum Home Forum Home > General > 12v Powered Systems
  New Posts New Posts RSS Feed - loud humming sound
  FAQ FAQ  Forum Search   Events   Register Register  Login Login

loud humming sound
 Post Reply Post Reply Page  12>
Author
Message
  Topic Search Topic Search  Topic Options Topic Options
ostrichmilkman View Drop Down
Registered User
Registered User
Avatar

Joined: 25 October 2010
Location: south norfolk
Status: Offline
Points: 137 		Post Options Post Options   Thanks (0) Thanks(0)   Quote ostrichmilkman Quote  Post ReplyReply Direct Link To This Post Topic: loud humming sound
    Posted: 02 March 2018 at 4:34am
hey guys. 

im trying to diagnose an issue im having.

my friend has been given some car audio bits (infitinty 475a, a set of infinty reference 6x9s and an infinty sub) im trying to make it run off a battery for him but im getting some horrible interference/ humming from both sets of channels. if i bridge the channels then i get no output whatsoever. the humming happens about ten seconds after i turn the amp on even when there is nothing plugged into the input so its definitely not being caused by a bad input. so maybe i've wired it up wrong. its been a while since i messed around with car audio stuff as i usually use smaller more efficient amps. 

i have a fairly thick wire running to the positive input and a smaller separate wire with a switch running to the the remote input. i then have a heavy wire (110 amp)  running from the ground of the amp back to the negative, all connections are solid and secure. 

at this point im thinking the amp has a fault but im just double checking with more knowledgeable types before we go ahead and scrap the amp. 

any input would be great. 
work like a dog party like animal
Back to Top
slaz View Drop Down
Old Croc
Old Croc
Avatar

Joined: 27 November 2009
Location: London E2
Status: Offline
Points: 2713 		Post Options Post Options   Thanks (0) Thanks(0)   Quote slaz Quote  Post ReplyReply Direct Link To This Post Posted: 02 March 2018 at 1:11pm
Sounds very much like the amplifier is faulty.

But anyway - if you're mate wants to use this gear as a standalone battery-powered sound system, forget that amplifier anyway. Get a 4ch full-range class D amp - use 2 channels for the 2 6x9's and bridge the other 2 channels for the sub (unless its a sub with <4R imepdance). Pioneer do a decent one for a good price ISTR.

That Infinity amp is a class AB design, and as such would almost certainly drain your battery much too quickly.
REMEMBER....POLITICIANS AND DIAPERS SHOULD BE CHANGED OFTEN AND FOR THE SAME REASON
Back to Top
ostrichmilkman View Drop Down
Registered User
Registered User
Avatar

Joined: 25 October 2010
Location: south norfolk
Status: Offline
Points: 137 		Post Options Post Options   Thanks (0) Thanks(0)   Quote ostrichmilkman Quote  Post ReplyReply Direct Link To This Post Posted: 03 March 2018 at 1:12am
it was only because he was given it all for free that we where going to use it/ bother making the thing in the first place, was hoping with a few dollars worth of leads and stuff i have lying around we could cobble it together. i warned him of the power usage and he was planning on just buying a whole heap of second hand batteries to counteract that problem, but if he wants to continue id definately try and get a much more efficient amp. do you know what the model number is for that amp ?

The problem is we are in new zealand and things are hard to get hold of and or ridiculously expensive compared to back home (uk) and it was more of just a mess around thing really. ive been trying to convince him to ditch the sub and run the 6x9s off a tripath style amp to make it a more affordable and more portable system, the amps cheap, we wouldnt need a big battery and thus could use a cheaper trickle charger. 

that would still be plenty loud for picnics and camping. but hes not convinced and wants to keep the sub, even though then it would be at the awkward stage of being too loud to play in parks or public  areas but not loud enough to have a proper party with out in the bush. 

anyway thanks for confirming my suspicion, ill keep an eye out for a second hand class d amp and maybe it will come into fruition.
work like a dog party like animal
Back to Top
slaz View Drop Down
Old Croc
Old Croc
Avatar

Joined: 27 November 2009
Location: London E2
Status: Offline
Points: 2713 		Post Options Post Options   Thanks (0) Thanks(0)   Quote slaz Quote  Post ReplyReply Direct Link To This Post Posted: 03 March 2018 at 1:32am
Oh gawd .... NZ.

Well - lots of pretty scenery, but god help you when wanting to buy any kind of tech.
Dick Smith LOLLOLLOL

I was in Wellington NZ for a few months a few years back .... coupla times I walked out of Dick Smith's in disgust at the prices. Have they still got TradeMe ? .... dunno about now, but then you couldn't even use paypal or anything - it was snailing cheques !

What you're saying is absolutely the best thing to do. Lepai 2020 (Lepy now) and a 12V 7A Lead battery and you'd be set.

Oh yeah - Pioneer 4ch amp is GM-D8604 .... about 130 quid or so in UK .... in Dick Smiths ??????




Edited by slaz - 03 March 2018 at 2:07am
REMEMBER....POLITICIANS AND DIAPERS SHOULD BE CHANGED OFTEN AND FOR THE SAME REASON
Back to Top
ostrichmilkman View Drop Down
Registered User
Registered User
Avatar

Joined: 25 October 2010
Location: south norfolk
Status: Offline
Points: 137 		Post Options Post Options   Thanks (0) Thanks(0)   Quote ostrichmilkman Quote  Post ReplyReply Direct Link To This Post Posted: 05 March 2018 at 4:17am
mate dont even get me started. still only have trademe no ebay no amazon, and tradme is the worst built website i have ever used.  and yes everything is mega expensive elsewhere. luckliy cash converters have just started an online auction site and no one uses it yet  so can find some good bargains on used kit. got a really nice sony head unit and some pionner 6x9s for my campervan for 50 bucks (25quid) all in. shame the head unit removal tools set me back 25 dollars !!!!!!! super cheap auto wanted 56 !!!!! for some shitty bits of metal. i got a split charge system for my leisure battery sent from the uk and even with 60 quid postage was still way cheaper than anything out here and got here just as quick. ali express has become quite a useful tool to, just a gamble on quality and takes about a month to turn up. and the price and quality of recreational substances... no wonder theres no free party scene hahaha. nz does make up for it though in the fact that its such a beautiful place and the people have a really layed back attitude. no running up escalators here. what was that about not getting started haha

do you reckon it would be worth trying to use the sub as a sort of passive radiator ?? 
work like a dog party like animal
Back to Top
Risc_Terilia View Drop Down
Young Croc
Young Croc


Joined: 15 December 2007
Status: Offline
Points: 699 		Post Options Post Options   Thanks (0) Thanks(0)   Quote Risc_Terilia Quote  Post ReplyReply Direct Link To This Post Posted: 05 March 2018 at 12:22pm
Learn the words?
Back to Top
slaz View Drop Down
Old Croc
Old Croc
Avatar

Joined: 27 November 2009
Location: London E2
Status: Offline
Points: 2713 		Post Options Post Options   Thanks (0) Thanks(0)   Quote slaz Quote  Post ReplyReply Direct Link To This Post Posted: 05 March 2018 at 2:57pm
Originally posted by Risc_Terilia Risc_Terilia wrote:

Learn the words?


Uh ???
REMEMBER....POLITICIANS AND DIAPERS SHOULD BE CHANGED OFTEN AND FOR THE SAME REASON
Back to Top
odc04r View Drop Down
Old Croc
Old Croc
Avatar

Joined: 12 July 2006
Location: Sarfampton
Status: Offline
Points: 5482 		Post Options Post Options   Thanks (0) Thanks(0)   Quote odc04r Quote  Post ReplyReply Direct Link To This Post Posted: 05 March 2018 at 3:36pm
Don't need to hum along if you know the words innit.
Back to Top
slaz View Drop Down
Old Croc
Old Croc
Avatar

Joined: 27 November 2009
Location: London E2
Status: Offline
Points: 2713 		Post Options Post Options   Thanks (0) Thanks(0)   Quote slaz Quote  Post ReplyReply Direct Link To This Post Posted: 06 March 2018 at 7:43pm
Ah OK - twigged now :-)

Hadn't paid much attention to the subject :-)
REMEMBER....POLITICIANS AND DIAPERS SHOULD BE CHANGED OFTEN AND FOR THE SAME REASON
Back to Top
ostrichmilkman View Drop Down
Registered User
Registered User
Avatar

Joined: 25 October 2010
Location: south norfolk
Status: Offline
Points: 137 		Post Options Post Options   Thanks (0) Thanks(0)   Quote ostrichmilkman Quote  Post ReplyReply Direct Link To This Post Posted: 07 March 2018 at 2:51am
LOL 
work like a dog party like animal
Back to Top
Sapro2 View Drop Down
Registered User
Registered User
Avatar

Joined: 31 January 2015
Location: Somerset
Status: Offline
Points: 354 		Post Options Post Options   Thanks (0) Thanks(0)   Quote Sapro2 Quote  Post ReplyReply Direct Link To This Post Posted: 07 March 2018 at 1:46pm
Dunno if you have fixed your problem yet but have you got an inverter running off the battery?
Some inverters / amp combinations can create really bad hum.

Just a thought
Splat Soundsystem
Baby Sham pram Soundsystem
Sapro - SoundCloud
https://soundcloud.com/sapro
DJ Sapro. West country free party DJ and Producer.
Back to Top
ostrichmilkman View Drop Down
Registered User
Registered User
Avatar

Joined: 25 October 2010
Location: south norfolk
Status: Offline
Points: 137 		Post Options Post Options   Thanks (0) Thanks(0)   Quote ostrichmilkman Quote  Post ReplyReply Direct Link To This Post Posted: 08 March 2018 at 2:15am
no inverter just the amp. im pretty  sure its fucked on top of the fact its just not that suibatble for the application. have ordered a ta2020 amp and battery and charger now so will go down that route. can anyone tell me what size barrel connector the lepai ta2020 uses ? need to buy a male and a female so i can run it from a wall socket whilst the battery is charging.  

or alternatively could anyone explain what circuit i need to be able to run the amp off the battery while the battery is charging without interference? 
 
work like a dog party like animal
Back to Top
 Post Reply Post Reply Page  12>

Forum Jump Forum Permissions View Drop Down

Forum Software by Web Wiz Forums® version 12.06
Copyright ©2001-2023 Web Wiz Ltd.

This page was generated in 0.078 seconds.