Question C6 head unit and speaker wiring is designed for 2 ohms

[Marschall67]

As I understand it, the 2 ohm stock wiring would be a larger AWG size and hence the 4 ohm would require smaller. So using the existing wiring should be acceptable, yes? Thanks in advance.

 

[Creedence85]

Lower impedance does increase resistance, but what are you planning with the system upgrade, as that will determine the best option. The speakers are 4 ohm, the head unit doesn't power the speakers, it sends line level signal to the amp mounted in the passenger footwell. The only instance where you'd reuse the speaker wiring would be replacing the speakers and continuing to power with the factory amp. If you were replacing the head unit and wanted to use its amp, or using an external amp, it would be easier to run new wire than tap the existing wiring as the amp is in the passenger footwell and connects with a harness.

 

[Marschall67]

Lower impedance does increase resistance, but what are you planning with the system upgrade, as that will determine the best option. The speakers are 4 ohm, the head unit doesn't power the speakers, it sends line level signal to the amp mounted in the passenger footwell. The only instance where you'd reuse the speaker wiring would be replacing the speakers and continuing to power with the factory amp. If you were replacing the head unit and wanted to use its amp, or using an external amp, it would be easier to run new wire than tap the existing wiring as the amp is in the passenger footwell and connects with a harness.

My plan was to replace the amp and speakers when upgrading the head unit. Kenwood/Hertz) I was understanding that the stock Bose speakers were 2 ohms? If they are already 4 ohms then the wiring I have should be ok yes?

 

[Dik]

The wires running to the speakers will work just fine. The resistance of the speakers is related to matching the impedance (resistance) to the amplifier.

 

[Creedence85]

The wiring should be fine, but it would probably be easier to replace the speaker wire instead of reuse the existing wire as you'll have to cut the wire at the amp harness in the foot well, extend to the amp, and cut the harnesses in the doors, though they do make adaptors for the speaker end.

 

[Dik]

if you have any technical.questions related to audio equipment you need to check out a community named Audioholics. There will be an article or posting explaining the differences between 2 and 4 ohm speakers and the effects of both on the amplifier.

 

[Creedence85]

The wires running to the speakers will work just fine. The resistance of the speakers is related to matching the impedance (resistance) to the amplifier.

@Dik the impedance is a result of the speakers as you said, but I think what @Marschall67 was referring to is if the factory wiring was more than adequate if it were thicker than normal. As impedance is lowered, insertion loss over distance increases which reduces audio quality, so you need thicker wire reduce the insertion loss. Longer runs on too thin a wire are higher resistance and increase the load on the amplifier.

 

[Marschall67]

if you have any technical.questions related to audio equipment you need to check out a community named Audioholics. There will be an article or posting explaining the differences between 2 and 4 ohm speakers and the effects of both on the amplifier.

Thanks, I will look for the audioholics, is that a FB thing?

 

[Marschall67]

@Dik the impedance is a result of the speakers as you said, but I think what @Marschall67 was referring to is if the factory wiring was more than adequate if it were thicker than normal. As impedance is lowered, insertion loss over distance increases which reduces audio quality, so you need thicker wire reduce the insertion loss. Longer runs on too thin a wire are higher resistance and increase the load on the amplifier.

Correct, I was told that the factory wiring had to be replaced when swapping out to a 4 ohm set up, due to that fact that the original amp and speakers are 2 ohms.

 

[Marschall67]

The wiring should be fine, but it would probably be easier to replace the speaker wire instead of reuse the existing wire as you'll have to cut the wire at the amp harness in the foot well, extend to the amp, and cut the harnesses in the doors, though they do make adaptors for the speaker end.

Thank you, I didn’t think the wires had to be replaced. I will look into some adaptors.

 

[Creedence85]

@Marschall67 As far as know, there is no adaptor for the amp harness, just the speaker harnesses. Look for Metra 72-4568, I'm trying to post here but it's removing the link.

Audioholics has a website with fairly extensive articles and reviews. They rely heavily on measurable data and are good at filtering between good gear and snake oil.

Home Theater Reviews, HDTV, HDMI Receivers

Home theater AV receiver, speaker, HDTV, television, projector and Blu-ray player reviews, buying guides, and high end audio and consumer electronics news

www.audioholics.com

 

[Creedence85]

Correct, I was told that the factory wiring had to be replaced when swapping out to a 4 ohm set up, due to that fact that the original amp and speakers are 2 ohms.

@Marschall67 Are you looking to have a shop do the work or do the work yourself. If a shop told you about 2 ohm in a C6, many factory Bose systems are 1-2 ohms, but the C6 seems to be closer to 3.5-4 ohm when measured, so I suspect they are generalizing about Bose systems, aren't familiar with the specifics of the C6, and I would be hesitant to let them touch the car.

I've been researching a stereo upgrade and the general consensus is to just replace the wire. For the $20 or whatever you'll spend on some decent copper wire, you'll get better wire, easier speaker and amp terminations, easier install since you just have to fish the new wire, and more amp mounting location options.

 

[Dik]

Creedence what you have posted is a tonne of good advice!

Further, Audioholics has published experts in their field. The members and posters are experienced audiophiles and practising electronic technicians and IMO an amazing resource themselves.

I understand what impedance is and why matching it is important ..... and in this case it has zero to do with the wiring to the speakers. I also understand I2R losses as I have done the calculation oh, a couple of times in electrical branch circuits and power distribution. NOTE: All these circuits were 120 v-ac or higher.....some much higher. I imagine Creedence, you can say the same.

What size is the existing wiring? 16AWG? How many Watts do you think he will hammer to the speakers? ....5? ....10? How many milliamps... ?

I'm sorry but I think this is just another case of internet over kill.

If the existing wiring is cut too short during the install then the wires will need to be replaced or lengthened (and a soldered splice will work just fine). Other than that, if the OP wants to create more work, well knock yourself out.

FWIW, I would be more concerned if the speaker change out was from 4 ohms to 2 ohms as you may put a amplifier with a 4 ohm output impedance at some risk when at maximum volume. That is THE impedance mis-match with real consequences and why any decent audio amplifier has circuit breakers that automatically reset or comes with a circuit breaker that is accessible for a manual reset.

My $0.02.

 

[Marschall67]

@Marschall67 Are you looking to have a shop do the work or do the work yourself. If a shop told you about 2 ohm in a C6, many factory Bose systems are 1-2 ohms, but the C6 seems to be closer to 3.5-4 ohm when measured, so I suspect they are generalizing about Bose systems, aren't familiar with the specifics of the C6, and I would be hesitant to let them touch the car.

I've been researching a stereo upgrade and the general consensus is to just replace the wire. For the $20 or whatever you'll spend on some decent copper wire, you'll get better wire, easier speaker and amp terminations, easier install since you just have to fish the new wire, and more amp mounting location options.

I will check the ohm rate myself to confirm but I am still doing research prior to pulling the trigger as this will be an expensive project. I am also on the fence on doing this my self or having a shop do it but frankly I don’t rust anyone anymore. All I get Is “sure we can do that” and end up finding poor quality and shotty work. Thanks again, I did register for audioholics so I’ll give that a go as well.

 

[Dik]

Marshall67. When it comes to stereo installs I couldn't agree more. I've had quite a few head units installed in my work trucks and I find that workmanship very poor.

 

[Creedence85]

@Marschall67 if shops you talk to don't know the specifics I'd move on. I naively had an alarm installed in my first car back in the late 90s when that's what the cool kids did and 18 year old me thought that was cool. A lot of the wiring was run loose, they used non insulated crimp connectors (even under the hood) and the alarm brain was just sitting loose under the driver side kick panel. I ended up tidying the wire, replacing the crimps under the hood, and mounting the brain. That was annoying enough on an 85 Grand Am so on the Corvette I think I'd die a little inside.

I've researched the stereo quite a bit and have most details sorted, so if you'd like to compare notes let me know. I have taken apart the center console and taken off the door panels which are no harder than other cars if you've done it before, so is quite doable. Installing hardware also looks relatively doable. There are door adaptors that adapt the factory sub holes to take a 6.5" speaker and then if you want to use component speakers the tweeters can be attached to the 3.5" speaker location in the door panel with a custom mount.

My plan is to use a Hertz DPOWER4 4 channel amp, 6.5" component speakers in the doors (possibly Hertz Dieci DSK 165.3) a 10" sub in a custom box, and power the sub by bridging 2 of the amp channels. The amp is small enough to fit in the footwell where the factory amp is, us 75 watts x4 and 150 watts bridged so should be fine for a pair of components and small sub. You can do rear speakers if you want, but 6.5" components should be excellent on their own making for a better stereo image than front and rear speakers, and using a single amp makes for a lower profile install.

Part of the reason I'm now on the fence is I made some minor improvements that increased the sound quality enough placing me more on the fence. I insulating the doors which made a small improvement to the clarity and the bass while removing some vibration. I then insulating the floor of the rear hatch area and behind the seats reduced road noise and removed some of the muddiness of the rear speakers. Before this I had the stereo faded forward but now I have it faded part way between front and rear. I also disconnectedh the center speaker further improved clarity and stereo separation. The center speaker isn't going anything special, it's just receiving a left/right sum signal to act as a fill, but it's tonality is not as clear as the door speakers and reduces the stereo image.

 

[Marschall67]

Creedence85, this is excellent. My plan is very similar and appreciate the info. I will compare notes more when I return from my trip this weekend. Thanks