Aftermarket HU: Resistor for sub "pop"

FinalJenemba · 07-28-2010, 11:18 AM

Just installed a new Pioneer HU in my 05 /w Audiophile. I did my research and got all the right harnesses so everything works great, I love it. But im getting the popping sound from the sub whenever I turn on the stereo. I read on here that a 1k ohm resistor in the amp turn on lead will fix this, but my question is, is it a 1/8 watt, 1/4 watt, or 1/2 watt resistor? Or does it matter?

Thanks!

2GreenAutos · 07-28-2010, 12:41 PM

Is Audiophile a factory amp/sub system? In any case I have used the PAC TR-4 turn on delay module with great results. It will delay the amp turn on 2 seconds and should get rid of that pop, ebay and sonicelectronix has them less than $20. Could you post up where you read about the resistor? I have only heard of diode isolating head units.

FinalJenemba · 07-28-2010, 01:52 PM

Quote:

Originally Posted by 2GreenAutos

Is Audiophile a factory amp/sub system? In any case I have used the PAC TR-4 turn on delay module with great results. It will delay the amp turn on 2 seconds and should get rid of that pop, ebay and sonicelectronix has them less than $20. Could you post up where you read about the resistor? I have only heard of diode isolating head units.

Post #2 http://www.focusfanatics.com/forum/s...light=resistor

Post #5 http://www.focusfanatics.com/forum/s...light=resistor

Post #4 http://www.focusfanatics.com/forum/s...light=resistor

I work at Radioshack and can grab a 1k resistor real easy, would much prefer that to ordering a $20 part of ebay if I could.

2GreenAutos · 07-28-2010, 02:37 PM

I see, I knew it was something about the factory stereo. Those things always need something wierd. Didn't know you needed to step down the voltage to the amp.

I am not an electrical engineer so you may want to wait for someone else to chime in. The way I understand it, the watt rating is the amout of heat the resistor can dissipate. The higher watt rating won't effect the resistance and just adds safety. http://www.bcae1.com/resistrs.htm Their calculator says 1000ohm @ 12v = .144 watts, so as long as you don't use the 1/8th it should be good.

YellowJellyBean · 07-28-2010, 03:05 PM

Yes, get a 1k ohm resistor that can handle a whole .144 watts of power without failing, and you'll be fine.

FinalJenemba · 07-28-2010, 03:55 PM

Quote:

Originally Posted by 2GreenAutos

I see, I knew it was something about the factory stereo. Those things always need something wierd. Didn't know you needed to step down the voltage to the amp.

I am not an electrical engineer so you may want to wait for someone else to chime in. The way I understand it, the watt rating is the amout of heat the resistor can dissipate. The higher watt rating won't effect the resistance and just adds safety. http://www.bcae1.com/resistrs.htm Their calculator says 1000ohm @ 12v = .144 watts, so as long as you don't use the 1/8th it should be good.

Quote:

Originally Posted by YellowJellyBean

Yes, get a 1k ohm resistor that can handle a whole .144 watts of power without failing, and you'll be fine.

I see, tanks guys! That makes a bunch of sense. You'd think after 2 years of working at Radioshack id have picked that up somewhere lol. But the truth is the few people that still come in to buy fuses and junk are pretty unpleasant and dont much care to talk.

Thanks again!

kkreit01 · 07-29-2010, 10:08 AM

You might want to read some more (on other forums, Mustang, etc.). I used the same harness with my 08 Sport Trac audiophile. I still had turn-on/off thump even with a 1K resistor. It wasn't horrible, and I could regulate it by turning the volume way down prior to stopping vehicle. Others recommended a different size resistor (I can't remember exactly). A voltage regulator would work better. This is just an FYI, that a 1K will help, but probably not eliminate the problem.

I quickly went all aftermarket, and sold the audiophile, so I didn't look into the problem any further, when I had my ST.

YellowJellyBean · 07-29-2010, 10:54 AM

Quote:

Originally Posted by kkreit01

I quickly went all aftermarket, and sold the audiophile, so I didn't look into the problem any further, when I had my ST.

Which is what I would recommend. I understand it's expensive, but you'll be much happier in the long run if you just replace the Audiophile setup.

quinnjdogg · 07-29-2010, 04:45 PM

I have always used a 1.5K resistor. You could also use a radio shack part # 276-1770. It is a 5 volt regulator that works perfectly, just a little tougher to install.

FinalJenemba · 07-29-2010, 11:27 PM

Quote:

Originally Posted by kkreit01

I quickly went all aftermarket, and sold the audiophile, so I didn't look into the problem any further, when I had my ST.

Quote:

Originally Posted by YellowJellyBean

Which is what I would recommend. I understand it's expensive, but you'll be much happier in the long run if you just replace the Audiophile setup.

Def not doin that. Iv never been dissatisfied with the way the Audiophile sounded, just wanted iPod control and BT. Im very happy with the way the system sounds. Im gonna try the resistor this weekend, if it doesn't work ill grab a volt reg and do it that way.

quinnjdogg: Could you give a quick description on how you wired your 5v reg up? Would help people finding this through google as well as me ;)

Edit: Just got to work and checked out the 5v reg, it really doesnt look any harder to hook up, just in, out, and tap into the ground wire. I think ill just go that route so I can get it right the first time. Thanks!

FinalJenemba · 07-31-2010, 12:17 AM

Just for people searching this. I ended up using a 1/2 amp 1.5k resistor just because it was so easy to try. It ended up working flawlessly. No pop, at all. Thanks very much for all the help!

quinnjdogg · 08-03-2010, 03:52 PM

what did you use for a crossover for the subwoofer? Normally, the crossover is built into the radio. When you go aftermarket, the sub will play all of the words and everything. We normally use a little electronic crossover to cure this problem on fords. I haven't done a focus yet so I don't know if this is an issue.

07-28-2010, 11:18 AM	#1
FinalJenemba Focus Jr. Enthusiast Join Date: Mar 2008 Fan#: 54270 Location: Tampa, FL, FL What I Drive: 2005 Silver ST Posts: 25 FF Reputation: 1 Buy-Sell-Trade Rating: (1)	Aftermarket HU: Resistor for sub "pop" Just installed a new Pioneer HU in my 05 /w Audiophile. I did my research and got all the right harnesses so everything works great, I love it. But im getting the popping sound from the sub whenever I turn on the stereo. I read on here that a 1k ohm resistor in the amp turn on lead will fix this, but my question is, is it a 1/8 watt, 1/4 watt, or 1/2 watt resistor? Or does it matter? Thanks!

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07-28-2010, 12:41 PM	#2
2GreenAutos Focus Enthusiast Join Date: Mar 2008 Fan#: 54691 Location: OKC, OK What I Drive: 2001 Green ZX3 Posts: 54 FF Reputation: 1 Buy-Sell-Trade Rating: (4)	Is Audiophile a factory amp/sub system? In any case I have used the PAC TR-4 turn on delay module with great results. It will delay the amp turn on 2 seconds and should get rid of that pop, ebay and sonicelectronix has them less than $20. Could you post up where you read about the resistor? I have only heard of diode isolating head units.

07-28-2010, 02:37 PM	#4
2GreenAutos Focus Enthusiast Join Date: Mar 2008 Fan#: 54691 Location: OKC, OK What I Drive: 2001 Green ZX3 Posts: 54 FF Reputation: 1 Buy-Sell-Trade Rating: (4)	I see, I knew it was something about the factory stereo. Those things always need something wierd. Didn't know you needed to step down the voltage to the amp. I am not an electrical engineer so you may want to wait for someone else to chime in. The way I understand it, the watt rating is the amout of heat the resistor can dissipate. The higher watt rating won't effect the resistance and just adds safety. http://www.bcae1.com/resistrs.htm Their calculator says 1000ohm @ 12v = .144 watts, so as long as you don't use the 1/8th it should be good.

07-28-2010, 03:05 PM	#5
YellowJellyBean Focus Addict Join Date: Sep 2009 Fan#: 69030 Location: San Luis Obispo, CA What I Drive: 2006 Screaming Yellow ZX3 SES Posts: 870 FF Reputation: 9 Buy-Sell-Trade Rating: (1)	Yes, get a 1k ohm resistor that can handle a whole .144 watts of power without failing, and you'll be fine. __________________ "My yellow, in this case, is not so mellow" -Jimi Hendrix Focus Fanatics Extremely helpful people I made a haiku

07-29-2010, 10:08 AM	#7
kkreit01 Focus Jr. Enthusiast Join Date: Jun 2010 Fan#: 76322 Location: Olathe, KS What I Drive: 2010 Sterling Grey SES Sedan Posts: 32 FF Reputation: 1 Buy-Sell-Trade Rating: (0)	You might want to read some more (on other forums, Mustang, etc.). I used the same harness with my 08 Sport Trac audiophile. I still had turn-on/off thump even with a 1K resistor. It wasn't horrible, and I could regulate it by turning the volume way down prior to stopping vehicle. Others recommended a different size resistor (I can't remember exactly). A voltage regulator would work better. This is just an FYI, that a 1K will help, but probably not eliminate the problem. I quickly went all aftermarket, and sold the audiophile, so I didn't look into the problem any further, when I had my ST.

07-29-2010, 04:45 PM	#9
quinnjdogg Focus Jr. Enthusiast Join Date: Jun 2010 Fan#: 76001 Location: rineyville, KY What I Drive: 2003 black svt Posts: 40 FF Reputation: 3 Buy-Sell-Trade Rating: (0)	I have always used a 1.5K resistor. You could also use a radio shack part # 276-1770. It is a 5 volt regulator that works perfectly, just a little tougher to install.

07-31-2010, 12:17 AM	#11
FinalJenemba Focus Jr. Enthusiast Join Date: Mar 2008 Fan#: 54270 Location: Tampa, FL, FL What I Drive: 2005 Silver ST Posts: 25 FF Reputation: 1 Buy-Sell-Trade Rating: (1)	Just for people searching this. I ended up using a 1/2 amp 1.5k resistor just because it was so easy to try. It ended up working flawlessly. No pop, at all. Thanks very much for all the help!

08-03-2010, 03:52 PM	#12
quinnjdogg Focus Jr. Enthusiast Join Date: Jun 2010 Fan#: 76001 Location: rineyville, KY What I Drive: 2003 black svt Posts: 40 FF Reputation: 3 Buy-Sell-Trade Rating: (0)	what did you use for a crossover for the subwoofer? Normally, the crossover is built into the radio. When you go aftermarket, the sub will play all of the words and everything. We normally use a little electronic crossover to cure this problem on fords. I haven't done a focus yet so I don't know if this is an issue.