abillybob Posted February 22, 2018 Posted February 22, 2018 Hi All Hopefully one of you lovely people know why this is happening. Basically I've been keeping myself busy lately to distract myself from thinking I'm working for the rest of my life... I'm sure that lottery win is around the corner So one of my most recent projects I set myself was to build a floor standing speaker with some old tat I had lying around upstairs in the loft from an old car. I've got an Xtrons Single DIN HU DL14DAB, 4 Woofers and Tweeters and I'm using the included cross overs to connect them up (Edge 306 Speakers) a Simple Edge Amplifier connected to a 8" Bass Face Subwoofer. I've heat shrinked and soldered all the correct connections together and purchased a AC240V to DC12V 40 Amp transformer to wire in the Amplifier and the HU to power, here it is. All seems to work just fine although I've noticed that at low volume there's an annoying boop boop boop boop boop noise coming from all the speakers including the subwoofer, it's like a low fast paced noise and when I turn the headunit off which turns off the amplifier at the same time the subwoofer will go "BLUP" loudly and then turn off. I thought it might be a grounding issue but they are all grounded to the correct terminals. I'm getting confused I've worked for months on this project and designed/built the custom box myself but that noise is really bugging me. Does anyone know why it might be doing this and if so any idea on how to remedy it Thanks All!
3s-gtech Posted February 22, 2018 Posted February 22, 2018 It's almost certainly because you're using AC to DC power through a separate supply. A 240v amp/source will deal with this properly. It's usually a bit cludgy doing this with car audio. You may improve things with a ground loop isolator, but no guarantees there.
Oaktech Posted February 22, 2018 Posted February 22, 2018 Yeah - What you can hear is the switch mode PSU dumping to ground, the same as you can quite often with laptops plugged into the mains and a large PA system. That's not the right PSU for the job. What you need is a big old linear power supply with a fat transformer and some big capacitors. You can prove the point by running it off another 12v source like a car battery, or a dumb 12v charger. What you're doing is a bit fudgey in the first place.
JATSO Posted February 22, 2018 Posted February 22, 2018 Hi All Hopefully one of you lovely people know why this is happening. Basically I've been keeping myself busy lately to distract myself from thinking I'm working for the rest of my life... I'm sure that lottery win is around the corner So one of my most recent projects I set myself was to build a floor standing speaker with some old tat I had lying around upstairs in the loft from an old car. I've got an Xtrons Single DIN HU DL14DAB, 4 Woofers and Tweeters and I'm using the included cross overs to connect them up (Edge 306 Speakers) a Simple Edge Amplifier connected to a 8" Bass Face Subwoofer. I've heat shrinked and soldered all the correct connections together and purchased a AC240V to DC12V 40 Amp transformer to wire in the Amplifier and the HU to power, here it is. All seems to work just fine although I've noticed that at low volume there's an annoying boop boop boop boop boop noise coming from all the speakers including the subwoofer, it's like a low fast paced noise and when I turn the headunit off which turns off the amplifier at the same time the subwoofer will go "BLUP" loudly and then turn off. I thought it might be a grounding issue but they are all grounded to the correct terminals. I'm getting confused I've worked for months on this project and designed/built the custom box myself but that noise is really bugging me. Does anyone know why it might be doing this and if so any idea on how to remedy it Thanks All! It's almost certainly because you're using AC to DC power through a separate supply. A 240v amp/source will deal with this properly. It's usually a bit cludgy doing this with car audio. You may improve things with a ground loop isolator, but no guarantees there. Agree with 3s-gtech on this one, had similar problems in my last job with using generators to power a PA System for The Duke of Kents visit back in 1992, lets put it this way we didn't here much of his speech and the hole i dug wasn't big enough for me to hide in. All the crowds could hear was thump thump thump from the speakers because the generator couldn't cope with the power being drawn:D
bald_pig Posted February 22, 2018 Posted February 22, 2018 Thirded, wrong PSU for the job, I don't think that ground loop isolators would be any help here I'm afraid.
abillybob Posted February 22, 2018 Author Posted February 22, 2018 (edited) Cheers both! I know it's not the perfect solution but I wanted to make use of my old Headunit. Is there like an actual risk of doing this i.e will I burn my house down or is it pretty safe just not a perfect solution? Where would I install the ground loop isolator? Would this go in place of the RCA cable that connects the headunit to the amp because even with the amp completely unplugged it still has a problem. The PSU powers it fine and there's quite a few reviews of the PSU on Amazon that show people doing exactly what I did with no issues. I also contacted the company and they said it should be fine... although I guess they'll say that as they're trying to sell it to me What PSU would I need? I can't hear the booping noise at mid-high volume but when it's turned low I can really frustrating!! Edited February 22, 2018 by abillybob
3s-gtech Posted February 22, 2018 Posted February 22, 2018 I think the suggestion, and certainly what I've seen people do with their car kit indoors, is to use something like https://www.ebay.co.uk/p/QJE-Qj1830sb-30amp-Linear-Power-Supply-Unit/1184365963?iid=172211182498 A GLI can sometimes help with reducing startup and turnoff thump. It won't reduce the wump wump wump sound when they're on though. 1
difinity Posted February 22, 2018 Posted February 22, 2018 Cheers both! I know it's not the perfect solution but I wanted to make use of my old Headunit. Is there like an actual risk of doing this i.e will I burn my house down or is it pretty safe just not a perfect solution? Where would I install the ground loop isolator? Would this go in place of the RCA cable that connects the headunit to the amp because even with the amp completely unplugged it still has a problem. The PSU powers it fine and there's quite a few reviews of the PSU on Amazon that show people doing exactly what I did with no issues. I also contacted the company and they said it should be fine... although I guess they'll say that as they're trying to sell it to me What PSU would I need? I can't hear the booping noise at mid-high volume but when it's turned low I can really frustrating!! No real risk fire wise but powering the head unit with "dirty" power will shorten the life of the main capacitor in it quite significantly as what it's receiving is out of spec for it. I think the noise you are hearing is the pulses of the PWM controller as it chops the voltage down to 12V. There were smoothing capacitors in mine (I repaired it at the weekend) but they aren't very big. They also don't have to be as it's just for LED lighting. I would think the typical buyer of these to power head units prefer loud to quiet music so reviews should be taken with a pinch of salt. There are a few cheaper alternatives to the one 3-gstech suggested, at that price you could buy several second hand proper house amps. 1
abillybob Posted February 23, 2018 Author Posted February 23, 2018 No real risk fire wise but powering the head unit with "dirty" power will shorten the life of the main capacitor in it quite significantly as what it's receiving is out of spec for it. I think the noise you are hearing is the pulses of the PWM controller as it chops the voltage down to 12V. There were smoothing capacitors in mine (I repaired it at the weekend) but they aren't very big. They also don't have to be as it's just for LED lighting. I would think the typical buyer of these to power head units prefer loud to quiet music so reviews should be taken with a pinch of salt. There are a few cheaper alternatives to the one 3-gstech suggested, at that price you could buy several second hand proper house amps. Cheers mate, I can't find any cheaper would you mind pointing me in the right direction?
3s-gtech Posted February 23, 2018 Posted February 23, 2018 There are a few cheaper alternatives to the one 3-gstech suggested, at that price you could buy several second hand proper house amps. Agreed. I'm looking at replacing my lovely Pioneer A/V amp because it has a blown channel - I can get a newer model for less than the cost of repair, and much less than the cost of that power supply! £100 buys you a lot of second hand home amp.
abillybob Posted March 7, 2018 Author Posted March 7, 2018 Cheers all for your help! So I was using it yesterday with the other half listening to some music for a couple of hours when the headunit would turn the sound off intermittently. I ensured it wasn't the bluetooth connection but that actual headunit was turning the sound off from the speakers and coming back on again for 2 seconds and then repeat. I turned it off and on again and it started working for another hour but then the music started to sound like it the speakers where under water? I have since turned it all off thinking it might have been what you guys said about being the wrong power supply. I'm a bit worried would I have done any permanent damage to the Headunit and seperate Edge Amplifier I have installed? If not I was thinking about getting on of these but not sure if they're ok and the right choice so hoping one of you guys could clarify for me? https://www.ebay.co.uk/itm/40a-bench-power-supply-13-8v-suit-12v-devices-CB-HAM-ICE-test-bench-40-amp-LAB/232548931382?epid=1805243905&hash=item3624ff1736:g:c~4AAOSwAC1Z~Hjs or https://www.ebay.co.uk/itm/Fusion-600W-40Amp-Adjustable-Power-Supply-O-FS-PS600ADJ/282718134740?epid=1410663405&hash=item41d35061d4:g:xT8AAOSwETJZ-zR4 They're both 40amp so presuming it should be able to power them fine as my headunit is only 15amp and Amplifier is 20amp although this isn't turned up much at all. Any help would be most appreciated, I've put days worth of work into this project making the box and everything else has been an ordeal so I'm hoping I haven't damaged anything permanently! What do you guys think?
Oaktech Posted March 7, 2018 Posted March 7, 2018 Does the head unit remain on, but just cut the sound out? That sounds like a head unit protecting itself - you need to check the maths of the speakers you've got connected. What rating are the speakers (4, 6, 8 etc) how many speakers do you have connected, are they connected together, are they connected in series or parallel? What does the manual for the head unit say it's minimum load is is (2, 4, 6 8, 16 ohms per channel etc) 1
abillybob Posted March 7, 2018 Author Posted March 7, 2018 Does the head unit remain on, but just cut the sound out? That sounds like a head unit protecting itself - you need to check the maths of the speakers you've got connected. What rating are the speakers (4, 6, 8 etc) how many speakers do you have connected, are they connected together, are they connected in series or parallel? What does the manual for the head unit say it's minimum load is is (2, 4, 6 8, 16 ohms per channel etc) Yes the headunit stays on just turns off the speakers but then the speakers come back on for 2 seconds and turn off again. I think I've done that right already, correct me if I'm wrong but basically the headunit is capable of 4 x 60 Watts rated at 4Ohms. All my speakers are 4Ohms 45Watt and connected independently, they came with tweeters also and they're connected to the headunit with the included crossovers. There is then a separate Edge Amplifier which is connected via RCA cable to the back of the headunit into the low input RCA to the amplifier. There is a remote wire connected from the headunit to the amp to turn it on when the headunit gets turned on. The amp is more than enough to power the small 8" subwoofer connected to it and the gain is only a 1/4 of the way up on the amplifier. Any ideas? As far as I'm aware everything is connected properly but it does seem like it's getting worse over time. Would this be down to using the wrong PSU? I was hoping buying one of the PSU's above would remedy this issue and also remedy the problem with the ticking noise at low volume? I'm just worried now that I've done permanent damage to the headunit or amplifier or both What are your thoughts?
difinity Posted March 7, 2018 Posted March 7, 2018 This stereo ? In Dash One Din LCD Screen Single Din DAB Car Stereo | Xtrons It doesn't make sense to me to buy a £100 power supply for a £70 car stereo. It's massive overkill also. I've just put a Chinese 240W stereo on my bench power supply, turned up full volume with two speakers connected. It's drawing 1.68A from my bench power supply. China watts aren't real watts. Remove the amp and connect the stereo to your car battery if you want to test it's ok before spending any money on power supplies. I have several house amps and an A/V receiver. None have cost over £100. 1
abillybob Posted March 7, 2018 Author Posted March 7, 2018 This stereo ? In Dash One Din LCD Screen Single Din DAB Car Stereo | Xtrons It doesn't make sense to me to buy a £100 power supply for a £70 car stereo. It's massive overkill also. I've just put a Chinese 240W stereo on my bench power supply, turned up full volume with two speakers connected. It's drawing 1.68A from my bench power supply. China watts aren't real watts. Remove the amp and connect the stereo to your car battery if you want to test it's ok before spending any money on power supplies. I have several house amps and an A/V receiver. None have cost over £100. That's the one thank you for all your help. The reason I was purchasing such high amp power supply is because it says on the specs on Xtrons website that the Max Current Draw is 15amp? Is this not the case then? The amplifier I have also connected is this one for a subwoofer. I could go and buy a home amplifier but I've already invested too much money and time into this build, plus the home amplifiers are big and won't fit in the box I've already created and I want it to be all part of one package. I've basically built a box that houses it all, speakers, headunit, amplifier, PSU and Subwoofer. Are you saying I'd get away with buying less Amp PSU then? What would you recommend? I only went to 40amp because the headunit says 15 and the amplifier has a 20amp fuse so I presumed 35amp
elsiegee40 Posted March 7, 2018 Posted March 7, 2018 (edited) That's the one thank you for all your help. The reason I was purchasing such high amp power supply is because it says on the specs on Xtrons website that the Max Current Draw is 15amp? Is this not the case then? The amplifier I have also connected is this one for a subwoofer. I could go and buy a home amplifier but I've already invested too much money and time into this build, plus the home amplifiers are big and won't fit in the box I've already created and I want it to be all part of one package. I've basically built a box that houses it all, speakers, headunit, amplifier, PSU and Subwoofer. Are you saying I'd get away with buying less Amp PSU then? What would you recommend? I only went to 40amp because the headunit says 15 and the amplifier has a 20amp fuse so I presumed 35amp 15 Amps! A basic bit of Physics... 15A multiplied by 230Volts = 3450 Watts. You could heat your house with it! EDIT I haven't read this thread so, sorry if I have taken it out of context. However, that is the basic calculation for Power Edited March 7, 2018 by elsiegee40
difinity Posted March 7, 2018 Posted March 7, 2018 (edited) So you've building everything into one box, like an old skool ghetto blaster ? That's not ideal as treble is directional, those speakers should be up high pointing down a little. Doesn't matter about the bass. I think you'll need to sort some sort of ventilation if you haven't already. Before picking a power supply you should verify the head unit is working. If it's faulty, you're just throwing good money after bad. Those ratings are for the fuse in case there is a short not a representation of it's power. It's a 12v power supply @elsiegee40 Edited March 7, 2018 by difinity 1
abillybob Posted March 7, 2018 Author Posted March 7, 2018 So you've building everything into one box, like an old skool ghetto blaster ? That's not ideal as treble is directional, those speakers should be up high pointing down a little. Doesn't matter about the bass. I think you'll need to sort some sort of ventilation if you haven't already. Before picking a power supply you should verify the head unit is working. If it's faulty, you're just throwing good money after bad. Those ratings are for the fuse in case there is a short not a representation of it's power. It's a 12v power supply @elsiegee40 Thanks so if I verify it's working tonight by hooking it up to my car battery which PSU should I buy? Ah ok so how do I find the actual true Amp rating that's needed?
difinity Posted March 7, 2018 Posted March 7, 2018 Thanks so if I verify it's working tonight by hooking it up to my car battery which PSU should I buy? Ah ok so how do I find the actual true Amp rating that's needed? You're welcome. You can measure the current draw with a multimeter as long as it can measure DC amps. It's connected in series. Here's a video to demonstrate. Do it for both the head unit then amp. Start with the volume on the head unit low then turn up the volume. 1
abillybob Posted March 7, 2018 Author Posted March 7, 2018 Ok shall do seems simple enough. Would you be able to just check those ebay links I sent before and let me know if those PSU's would be any better too?
abillybob Posted March 8, 2018 Author Posted March 8, 2018 So I've checked it and all seems to be working... Phew. Left it hooked to a car battery ! So if I buy those power supplies will that alleviate my issues? Thanks in advance!
difinity Posted March 8, 2018 Posted March 8, 2018 I believe this would be more suitable https://www.ebay.co.uk/itm/UK-version-Switch-mode-20A-13-8V-bench-top-power-supply-650-661UK/262988543849 but without those measurements I can't say for sure.
PotNoodleTech Posted March 8, 2018 Posted March 8, 2018 Well - it sounds like the AC - DC transformer to me. One way to check for aboloute sure, would be to plug a 12v car battery in instead and see if the pulsing noise goes away. If it does, then you know it's the transformer and will have to buy a better one.
abillybob Posted March 8, 2018 Author Posted March 8, 2018 I believe this would be more suitable https://www.ebay.co.uk/itm/UK-version-Switch-mode-20A-13-8V-bench-top-power-supply-650-661UK/262988543849 but without those measurements I can't say for sure. Wouldn't that still cause problems though considering it's a switching Power Supply? I thought I needed a Linear one?
woodham Posted March 9, 2018 Posted March 9, 2018 you coupd always stick some bloody big power caps between the supply and your connections , we use to do that to cars that had under powered alternators in them to smooth things out , id still be inclined to just call it a day and buy a propper 230v amp
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