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HK subwoofer ohm rating

wormycp

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I am looking to disconnect the factory hk sub and put an aftermarket under rear seat. I want to use the factory amp. I wondered if anyone knows the impedance of the factory sub. I don't want to fry my amp.
2019 Ram 1500 Laramie. U connect 12" with Harmon Karson System.
 
I am looking to disconnect the factory hk sub and put an aftermarket under rear seat. I want to use the factory amp. I wondered if anyone knows the impedance of the factory sub. I don't want to fry my amp.
2019 Ram 1500 Laramie. U connect 12" with Harmon Karson System.

I've been out of the car audio game professionally for about 12 years now, so I'm going off of my knowledge from then, not sure how much factory amplified systems have changed since then. With that being said, we would never connect an aftermarket sub to a factory amplifier for multiple reasons.

1: Usually factory speaker resistance is much higher than aftermarket. I've seen factory stuff range from 8 all the way to 16ohms, while most aftermarket is 2-4 ohms. Yes you could wire 2 4ohm subs in series and make it an 8ohm load, but that brings me to the next reason...

2: Your factory amp isn't going to be anywhere near powerful enough to push most aftermarket Subs. While it will probably make it "Play" the lack of power to drive it will make the upgrade pretty much not even noticeable, if not make it sound even worse than it did stock.

3: This one is probably the most important... It WILL void your warranty! If anything does happen to the sound system, amp - speakers- radio - ect, regardless if its because of the aftermarket upgrades or not, the dealer will blame it on that... and good luck trying to prove them wrong!

I had the last issue with a jeep that had aftermarket amp/speakers installed (factory amp bypassed) The radio went bad in it (the radio still functioned but the screen wouldn't come on). The dealer tried blaming it on the aftermarket equipment saying it was causing the radio to overheat. After arguing with them they finally agreed to replace it "This once" and acted as if they were doing me a huge favor.
 
I am looking to disconnect the factory hk sub and put an aftermarket under rear seat. I want to use the factory amp. I wondered if anyone knows the impedance of the factory sub. I don't want to fry my amp.
2019 Ram 1500 Laramie. U connect 12" with Harmon Karson System.
I work for Harman (BTW it's Harman/Kardon) and am very familiar with that speaker as I'm the engineer who works on FCA speakers. The sub in the new Ram is a single voice coil 10 inch in a 9 liter box. The speaker is rated at 6 ohm impedance. That speaker is pretty impressive in that little box. It's an inverted motor (shallow design) using a neodymium rare earth magnetic motor. You can get more in a larger box with a larger speaker for sure but it cost you some precious space to do much better. If you want more bass,..you may want to just add another sub instead of replacing that one and keep the amp. There are aftermarket subs that could be wired into the system that would augment the bass if that is what you are looking for. I'd recommend to look at a consumer Car audio JBL powered subwoofer box. Something like this to add into your system( https://www.jbl.com/car-subwoofers/...ASSPRO12___color=Black-GLOBAL-Current#start=1). That's a JBL GT BASS PRO if the link doesn't work.
 
I work for Harman (BTW it's Harman/Kardon) and am very familiar with that speaker as I'm the engineer who works on FCA speakers. The sub in the new Ram is a single voice coil 10 inch in a 9 liter box. The speaker is rated at 6 ohm impedance. That speaker is pretty impressive in that little box. It's an inverted motor (shallow design) using a neodymium rare earth magnetic motor. You can get more in a larger box with a larger speaker for sure but it cost you some precious space to do much better. If you want more bass,..you may want to just add another sub instead of replacing that one and keep the amp. There are aftermarket subs that could be wired into the system that would augment the bass if that is what you are looking for. I'd recommend to look at a consumer Car audio JBL powered subwoofer box. Something like this to add into your system( https://www.jbl.com/car-subwoofers/...ASSPRO12___color=Black-GLOBAL-Current#start=1). That's a JBL GT BASS PRO if the link doesn't work.
What is the wattage rating for the factory sub if it is 6 ohm's.?
 
"Watt ratings" are a funny thing because after market and OEM have tremendously different requirements for life testing products.
Typical after market products rate power with an 8 hour power test. Power test are basically how much power can the loudspeaker endure usually using a broadband noise input like pink noise at some voltage input level. Say for instance it's a 4 ohm speaker and it's rated as a 100 watt speaker. For after market products that typically means the product can reliably handle a 20Vrms input for 8 hours straight. Buyer beware, because some aftermarket product makers play games with "music watts" or "peak power ratings" by simple multiplying their 8 hour test wattage by 4 to advertise power that might be better than their competition. In the case I mention an aftermarket manufacture may say their 100W speakers can handle 400W peak power. The 400W "advertisement" should be taken with a grain of salt. What you really want to pay attention to much more than a watt rating is the loudspeakers "Sensitivity rating". Sensitivity rating is only provided by a reputable after market manufacturer and is typically a 1 Watt input that yields a certain SPL (Sound Pressure Level) output at 1 meter distance. A decent sensitivity rating for a sub woofer might be 95dB with a 1 watt input at a 1 meter distance. A 1000W subwoofer may not be as good as a 250W subwoofer because it's the sensitivity rating that matter more for good sound over how much power can I dump into a speaker before it blows up. OEM requirements for power testing and rating speakers are very different. OEMs typically require 1000 hour power tests to qualify production speakers (plus a lot of other crazy environmental torture tests). I can't tell you what your OEM speaker was qualified to because it's confidential with FCA but I can tell you that your OEM speakers have been thoroughly tested much more stringently than any aftermarket product.
 
I ran some testing in another thread last month or so ago. I added an AP4-CH41 for testing with an Audiobahn sub & Soundstream amp.

I removed that and then back-probed the sub outputs from the amp under the driver's seat. I grabbed a set of dual speaker subs from a Challenger and wanted to see how much more I could deepen the bass. The Challenger sub box has 2 speakers with dual voice-coils - but that system only uses 3 of the coils from the head unit. I simply placed one of the connections to the back-probing (putting in parallel with the stock HK sub behind the rear passenger seat). Sounded good. Added a second. Sounded roughly the same but I liked the lower tones the system was able to play. I'm creating my own additions to place under the rear seat (I have the fold-out storage under the seat, so I'm making my own setup since all the online versions would require me to remove my storage.)

As @YnotGlenbo and @Futureboy61 pointed out -- I take this all on my own (if something happens, then I am responsible -- doesn't hurt I have a great job at a local dealership, so I can get parts easy enough). Placing 1 4 ohm speaker in parallel to the stock 6 ohm speaker gives you a total Sub Ohm of roughly 2.4 (adding that 3rd in-line gave me roughly 1.43 and I was afraid the stock amp would fail). I did try switching my connections around and made the two 4 ohm into series (aka 8 ohm) which gave me roughly 3.43 ohms. Sounded good as well.

Just some food for thought and give you some examples of what you can do.
 
204 Watts
Thanks, I would not think it was even that considering how the HK sub looks. I may be tempted to try and drive it with an external amp since my Bighorn only has the 5 speaker radio and I picked up the HK sub off of Ebay for a really good price.
 
Futureboy61,

Any insight as to why our eq on the HK 19 speaker stereo system is limited to bass mid and high? I remember my mom’s ‘89 Plymouth Grand Voyager with the factory Infinity stereo system had more(5?) frequency adjustments.

I’d like to filter out some of the higher frequencies from my sub
 
Futureboy61,

Any insight as to why our eq on the HK 19 speaker stereo system is limited to bass mid and high? I remember my mom’s ‘89 Plymouth Grand Voyager with the factory Infinity stereo system had more(5?) frequency adjustments.

I’d like to filter out some of the higher frequencies from my sub

I wish I had the answer to that question! I was kind of shocked and slightly disappointed when I pulled up the eq the first time and only saw the 3!!


Sent from my iPhone using Tapatalk
 
I work for Harman (BTW it's Harman/Kardon) and am very familiar with that speaker as I'm the engineer who works on FCA speakers. The sub in the new Ram is a single voice coil 10 inch in a 9 liter box. The speaker is rated at 6 ohm impedance. That speaker is pretty impressive in that little box. It's an inverted motor (shallow design) using a neodymium rare earth magnetic motor. You can get more in a larger box with a larger speaker for sure but it cost you some precious space to do much better. If you want more bass,..you may want to just add another sub instead of replacing that one and keep the amp. There are aftermarket subs that could be wired into the system that would augment the bass if that is what you are looking for. I'd recommend to look at a consumer Car audio JBL powered subwoofer box. Something like this to add into your system( https://www.jbl.com/car-subwoofers/...ASSPRO12___color=Black-GLOBAL-Current#start=1). That's a JBL GT BASS PRO if the link doesn't work.
Do you know why the factory amplifier is not sending a flat bass signal to the subwoofer? In my testing, there's a large dB boost in the 70 Hz area and it sounds awful - really boomy bass at times as a result. Doesn't matter what I set the head unit EQ to, the signal is still molested by the time it gets to the sub.

I know this because I charted the frequency response and actually went through the trouble of buying a small Kicker amp and a PAC AP4-CH41. The PAC hooks up in-line behind the screen and sends a true flat audio signal to the Kicker amp, which I then wired up to the factory subwoofer, thus removing the signal/power from the factory amplifier in the process. Everything sounds MUCH better just by feeding the factory sub a flat signal, which you can then EQ with the PAC or Kicker amp as you please. I really don't understand how the audio engineers let the system pass this way. It's one of the worst audio systems I've ever heard because of the drastic bass boost to some frequencies in the factory amp. An amplifier software update needs to be released to fix this.

This is not a one-off thing either. I've had multiple 5th gen Limited trucks and they've all had the issue on the current amplifier software (unless something changed in the last few months).
 
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Do you know why the factory amplifier is not sending a flat bass signal to the subwoofer? In my testing, there's a large dB boost in the 70 Hz area and it sounds awful - really boomy bass at times as a result. Doesn't matter what I set the head unit EQ to, the signal is still molested by the time it gets to the sub.

I know this because I charted the frequency response and actually went through the trouble of buying a small Kicker amp and a PAC AP4-CH41. The PAC hooks up in-line behind the screen and sends a true flat audio signal to the Kicker amp, which I then wired up to the factory subwoofer, thus removing the signal/power from the factory amplifier in the process. Everything sounds MUCH better just by feeding the factory sub a flat signal, which you can then EQ with the PAC or Kicker amp as you please. I really don't understand how the audio engineers let the system pass this way. It's one of the worst audio systems I've ever heard because of the drastic bass boost to some frequencies in the factory amp. An amplifier software update needs to be released to fix this.

This is not a one-off thing either. I've had multiple 5th gen Limited trucks and they've all had the issue on the current amplifier software (unless something changed in the last few months).
Just got my 2019 3500 longhorn back from dealer- they started a case with fca- end result they replaced the amp. It sounds better and supposedly now meets design specs- but still no boom from sub. My2015 Xterra has a OEM rockford fosgate that blows away the HK , Better but still disappointed. AND it seems completely unable to decode music on Sirrus XM.
 
Futureboy61,

Any insight as to why our eq on the HK 19 speaker stereo system is limited to bass mid and high? I remember my mom’s ‘89 Plymouth Grand Voyager with the factory Infinity stereo system had more(5?) frequency adjustments.

I’d like to filter out some of the higher frequencies from my sub
The older radios with the 5 band EQ were commonly set to a "smiley" face setting by most consumers. The EQ's even though there were 5 controls were really Bass Mid and Treble controls. It's about cost. Also all the controls now are through a DSP now in the amplifiers and the older stile controls were analog in the head units, The sub should only be operating at 200 Hertz and lower and really most of the energy from the sub is occurring below 100 Hz. You could always add an passive low pass filter inductor to the sub input if you needed to, something like a audio rated 6.4mH coil in series would work. That would give you a low pass filter at 150Hz for the sub. If you used a 10mH coil in series with your HK sub, your Xover frequency would be 100 Hz
 
The older radios with the 5 band EQ were commonly set to a "smiley" face setting by most consumers. The EQ's even though there were 5 controls were really Bass Mid and Treble controls. It's about cost. Also all the controls now are through a DSP now in the amplifiers and the older stile controls were analog in the head units, The sub should only be operating at 200 Hertz and lower and really most of the energy from the sub is occurring below 100 Hz. You could always add an passive low pass filter inductor to the sub input if you needed to, something like a audio rated 6.4mH coil in series would work. That would give you a low pass filter at 150Hz for the sub. If you used a 10mH coil in series with your HK sub, your Xover frequency would be 100 Hz

For the record the EQ in my Mom’s van did look like a smiley face IIRC. Ha. That was a great factory stereo for the time. Truth be told that Plymouth and the Infinity stereo are partly to blame for my brand loyalty to both of those respective companies.
If all of this frequency adjustment is done through a DSP through the GUI, strictly out of curiosity, is it possible for FCA to add more tuning control with a software change or are we getting into hardware change territory now?
Thank you for your insight and sharing your expertise!
 
For the record the EQ in my Mom’s van did look like a smiley face IIRC. Ha. That was a great factory stereo for the time. Truth be told that Plymouth and the Infinity stereo are partly to blame for my brand loyalty to both of those respective companies.
If all of this frequency adjustment is done through a DSP through the GUI, strictly out of curiosity, is it possible for FCA to add more tuning control with a software change or are we getting into hardware change territory now?
Thank you for your insight and sharing your expertise!
For the record the EQ in my Mom’s van did look like a smiley face IIRC. Ha. That was a great factory stereo for the time. Truth be told that Plymouth and the Infinity stereo are partly to blame for my brand loyalty to both of those respective companies.
If all of this frequency adjustment is done through a DSP through the GUI, strictly out of curiosity, is it possible for FCA to add more tuning control with a software change or are we getting into hardware change territory now?
Thank you for your insight and sharing your expertise!
I'm glad you are a fan. Infinity is a Harman brand and the 1st Chrysler sound systems (at the time it was just Chrysler) were very good OEM audio systems that made both Chrysler and Harman a lot of money. My guess is you already know this but there are some ways to manipulate the sound system using the speed sensitive volume settings along with the tone controls. Outside of those two places in the head unit, there is no place to control the sound from the OEM system. I'm pretty sure FCA has a suggestion site for feed back for their vehicle owners...might even be this forum. I would make the suggestion for more user sound controls and yes, it's all new software programming that makes that happen. I think it would be kind of cool for the head units to have "Easter Egg" software features for those who wanted "extra" customizable control features for their infotainment system. If you ask...they may build it.
 
I'm glad you are a fan. Infinity is a Harman brand and the 1st Chrysler sound systems (at the time it was just Chrysler) were very good OEM audio systems that made both Chrysler and Harman a lot of money. My guess is you already know this but there are some ways to manipulate the sound system using the speed sensitive volume settings along with the tone controls. Outside of those two places in the head unit, there is no place to control the sound from the OEM system. I'm pretty sure FCA has a suggestion site for feed back for their vehicle owners...might even be this forum. I would make the suggestion for more user sound controls and yes, it's all new software programming that makes that happen. I think it would be kind of cool for the head units to have "Easter Egg" software features for those who wanted "extra" customizable control features for their infotainment system. If you ask...they may build it.
Ok ok, Love my Ram 2020 Limited but really, the radio sound is nowhere near as good as my 2011 Ram Laramie. 19 speakers but all tuned to sound flat with very little bass. Most of the sound is right in your face and has to be adjusted to the rear more. Surround sound is just ok and so for all the hype on this system, lets be honest here, it's just not that good. Period. You can tell me how much it has been tested and what kind of incredible engineering standards were used to produce the speakers etc but my ears are just not hearing it. The radio functionality is awesome and the screen is incredible. But the sub woofer is lame and so the system just doesn't sound good. Sorry HK guy, but HK has some serious work yet to do on this system.
 
Ok ok, Love my Ram 2020 Limited but really, the radio sound is nowhere near as good as my 2011 Ram Laramie. 19 speakers but all tuned to sound flat with very little bass. Most of the sound is right in your face and has to be adjusted to the rear more. Surround sound is just ok and so for all the hype on this system, lets be honest here, it's just not that good. Period. You can tell me how much it has been tested and what kind of incredible engineering standards were used to produce the speakers etc but my ears are just not hearing it. The radio functionality is awesome and the screen is incredible. But the sub woofer is lame and so the system just doesn't sound good. Sorry HK guy, but HK has some serious work yet to do on this system.
Please give your feedback through the FCA survey. FCA actually pays attention to their customer feedback. If you can be a little more specific as to what you are missing with the system sound it would be a great help. What's missing in the low end that you don't like in the 202 system? What are your ears not hearing that was present in the 2011 Laramie?
If you live in the Detroit area...maybe we can have a look at your vehicle to see if it's doing what it should be doing.
 
Please give your feedback through the FCA survey. FCA actually pays attention to their customer feedback. If you can be a little more specific as to what you are missing with the system sound it would be a great help. What's missing in the low end that you don't like in the 202 system? What are your ears not hearing that was present in the 2011 Laramie?
If you live in the Detroit area...maybe we can have a look at your vehicle to see if it's doing what it should be doing.
You missed my concern. The HK amplifier is sending a boosted signal to the subwoofer. The bass is overwhelming in some frequency areas. I have noticed this in several 2019 and 2020 Limited trucks, so clearly it's a software tuning issue. I had to use aftermarket equipment to send a flat, high level RCA signal to my own amplifier, and then hooked up the factory subwoofer to the aftermarket amplifier. This completely fixed the boosted bass the subwoofer was putting out from the HK amp. And the 3 band EQ on the screen can't be used to fix it, because not all the bass frequencies are boosted, plus you would lose the already anemic response the door 6x9s put out.

In short:
1. HK amp boosts the subwoofer too much... please check this because I think it's far from a relatively flat output.
2. Door 6x9 bass output is very low.

I've given feedback to FCA. I do hope they listen, but the bean counters are going to be a limiting factor. FCA charges $1K-$2K for these audio upgrades, but then throw in what look like $20 speakers. I'd like a better return on investment when buying an upgrade. The Bowers & Wilkins system in my wife's Volvo was $3,400 and it was worth every cent. 10" infinite baffle carbon fiber subwoofer. 1" aluminum dome Nautilus (minimizes reflection from the driver housing) tweeters, including 1 ON the dash facing the passengers to minimize glass reflection. 4" & 3" Kevlar fiber mid drivers. 6.75" woofers. It is the absolute best audio system I've ever heard in a vehicle, and considering cars in the 6 figure price range are using this same B&W hardware, Volvo did something right by fairly delivering on the price people paid for an audio upgrade.
 
392DCGC, The Bowers and Wilkins system in the Volvo is a Harman system too and that system is a level up in performance. The B&W system is a very good system, I'm glad you are enjoying that system. The products in the Volvo are different than the HK system and the system tuning is also different between those vehicles. Regardless you as a paying customer should get what you believe to be of value for buying an upgraded audio system. FCA sets the production level performance so maybe an EQ change should be investigated. Sometimes door speakers are limited to reduce buzz and rattle issues. Here is the H/K support site: https://www.harmankardon.com/support-contact.html I'm not sure what can be done if the system is working as designed but you certainly can voice your concerns and I will makes sure your concerns are heard.
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Ok, so I am no engineer but I know what my ears hear and there is a serious lack of "punch" to the bass in this system! Don't really know how else to describe it but it just misses sound definition all around. The highs could be clearer and the lows could be clearer and the music just sounds flat to me. Lower cleaner lows with "PUNCH" and higher cleaner highs with more clarity. The music as is sounds "muddy"! So what ever the technical terms are for all the above descriptions...i just don't know, but I think you know what I mean. LOL. Regardless, the sound of the system still is acceptable, it's just not as good as my 2011 Boston Acoustics Ram System. However, the technology blows the 2011 system away. Best overall radio technology I have ever owned. But let's be honest here, the sound is just OK!
 

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