SmallTruk Posted February 21, 2012 Report Share Posted February 21, 2012 I've had an annoying high pitch, low volume tone coming from my speakers and narrowed it down to one of the SAZ3000's I have strapped. RCA's disconnected from the amp and the sound is gone. I also diacovered that if I tap on the case of the amp that's causing the noise it'll make a crackling sound from the speakers with each tap. Everything was fine until I put in the 2nd amp. Bought it used so I don't know the total history. Anybody have an idea of what inside the amp could be causing this issues? Quote Link to comment Share on other sites More sharing options...
Wicks Posted February 23, 2012 Report Share Posted February 23, 2012 High pitch noise and a tap induced crackle sounds like a broken/cracked solder joint in the signal path. Pull the cover and look for a bad solder joint at the rca's and through the remaining signal path. Make sure all your grounds are solid. Quote This post sent with 100% recycled electrons. 2004 BMW M3Mechman 280A 2 - XS Power XP30001 - XS Power D375 500F of Maxwell SuperCaps (soon to be 1000F) iPadMini2Dash mounted O-scopeAudison bitOne (Remote DRC MP) Highs Amp - PPI Art A404 Hertz HSK130 (HSK165 waiting...) DC Audio DC9.0K 2- DC Audio XL12m2LEGAL - 147.3dB @ 41Hz OUTLAW - 150.2dB @ 45Hz OUTLAW - 145.7dB @ 30Hz JUNE 2014 SOTM WINNER 2014 COLORADO PEOPLE'S CHOICE WINNER SOTM BUILD:http://www.stevemeadedesigns.com/board/topic/141656-wicks-e46-m3-build-bass-turbo-button-and-a-big-new-addition/page-68#entry2802026 Link to comment Share on other sites More sharing options...
SmallTruk Posted February 24, 2012 Author Report Share Posted February 24, 2012 Finally got a chance to yank it out. Pulled the cover and didn't see any broken joints. Put it back together and hooked it back up to try pinpoint it better. Figured out that if I wiggle the RCAs it'll make the crackling sound. Also found out that if Im holding the RCA and touching the plate they're mounted to I actually got a small shock. I'm guessing that the tone I'm hearing is AC voltage that's being induced into the RCAs from that one amp. Just need to yank it out again and try pinpoint where it's bad. Any ideas? Quote Link to comment Share on other sites More sharing options...
CLNFREAK Posted February 24, 2012 Report Share Posted February 24, 2012 my AB 1100.1 made a sound when I would hit bumps in the road..... the solder joint where they were connected to the board was broke... ARC in ohio found it and fixed it for me ... i couldnt see it was broke Quote Link to comment Share on other sites More sharing options...
SmallTruk Posted February 24, 2012 Author Report Share Posted February 24, 2012 The RCAs on the saz are connected to the board via a set of cables with plugs that go into the board. So with that I'm kinda thinking it's one of the RCA plugs that's tightened on the end cap that's got a bad joint somewhere. Might just swap those pieces from one amp to the other to confirm that's what it is. Easier than taking all the time to re solder only to find out its something else. Quote Link to comment Share on other sites More sharing options...
Watch the bass Posted February 24, 2012 Report Share Posted February 24, 2012 my AB 1100.1 made a sound when I would hit bumps in the road..... the solder joint where they were connected to the board was broke... ARC in ohio found it and fixed it for me ... i couldnt see it was broke Never saw a cold solder in person, but i had a vew! You couldn´t see cold solder normaly Quote "in the abundance of water, the fool is thirsty" Bob Marley Link to comment Share on other sites More sharing options...
SmallTruk Posted February 25, 2012 Author Report Share Posted February 25, 2012 So here's what I figured out: All solder joints around RCAs are good, swapped end cap with RCA's to confirm. With the RCA piece screwed in place on the amp, it goes into protect. If I remove that piece and just leave the two plugs from the RCA's connected to the board it starts up fine. The high pitch tone is there when the amp isn't in protect (end piece not screwed in place) but if I ground the outside of one of the RCAs the high pitch tone disappears. Any idea what's going in here? I know it ain't the RCA's on the amp but I'm thinking it's some type of ground problem in the amp. Help... Quote Link to comment Share on other sites More sharing options...
timwebb Posted February 25, 2012 Report Share Posted February 25, 2012 a cold solder joint will look rough and dull, a good joint is smooth and shiny. Quote Link to comment Share on other sites More sharing options...
SmallTruk Posted February 25, 2012 Author Report Share Posted February 25, 2012 I swapped the end piece that holds the RCAs and their soldered connections with the other amp I had and it was fine. Took it out and checked everything again. Noticed that the power AND protect light are both on. Also, with the end piece in place if I touch the outer metal of the RCA and the case I get shocked. Nothing major but enough to feel it and know its there. Quote Link to comment Share on other sites More sharing options...
STEvil Posted February 25, 2012 Report Share Posted February 25, 2012 sounds more like your amp has a long lead somewhere that is touching the casing Quote MickyMcD - "Capable of making some serious trouser flapping volumes at where's-my-testicles frequencies, the Servo-Drives used to be fairly jaw dropping..." Any time you have have a power wire next to your frame put some rubber hosing (or cut up an innertube) around it. The wire is bound to wiggle (due to driving or flex) and the casing will eventually wear through. Hammerdown... 1% no links to outside websites, business related FB/YT pages allowed. Link to comment Share on other sites More sharing options...
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