8.4A NON-Alpine and signal summing

[mefferz]

Hello,

Earlier this year I replaced my factory 6 speaker setup with Arc 6.2 comps in the front, HAT Mirus 6x9s in the rear, powered by an Arc 450.4 amp. Also had an Arc XDi 10" glassed into one of the storage bays under the rear seat powered by an Arc 650.1. I'm using an AudioControl DQ-61 for processing. All doors have been deadened with Roadkillz. I've spent many hours tweaking the EQ with mixed results. I was always chasing the midbass and vocals. It never felt full to me.

I never attempted the signal summing feature on the DQ-61 because I've read from numerous posts that it wasn't needed for the non-Alpine configuration. Well after finally trying it out, I can tell you from experience that's not true. It makes a huge difference. The uConnect HU must have some sort internal crossovers for the front and rears. The fronts no longer sound anemic and I had to raise the high-pass at the amp from 50hz to 100hz to keep the bass under control and let the sub do it's job. I wish I wouldn't have waited 9 months to try out the feature.

I'm curious if other people have had the same experience?

 

[j1877p]

No experience with it as of yet but I will be watching the replies. I haven't started my audio build yet but I have the 8.4a and often wonder if it wouldn't be better to just go aftermarket and sell it. Only thing is getting factory options to work with aftermarket (backup cam, blu-tooth mic, Nav antennae). So chances are I will probably be keeping the 8.4a and be going about it as you have and summing the signals and tuning. Glad you were able to find out at least that us without the Alpine system still need to sum the signal. I too was under the assumption we did not need to do it.

 

[troutspinner]

I think you are hearing a difference simply because you are feeding more voltage to the DQ.

On my 8.4a Non-Alpine, I used the front signal for inputs into my DSP and I can tell you with certainty that it is a full signal as measured with a mic and REW.

Just as a comparison, when I was feeding my front mid-bass 75 Watts each, I did feel that my system was missing that full and powerful sound. When I increased the wattage to 200 to each mid-bass, it was a night and day difference and the system was now that full powerful system everyone wants to have.

It's been about 10 months or so since I last played with any setting on my system and it just continues to sound amazing to me and I get compliments all the time.

 

[troutspinner]

If you really want to blow your mind, disconnect your rears and then bridge all of the power to the front. You'll hear what those speakers are really supposed to sound like.

Fair warning if you do, you will either tie your rears back into stock or buy an an additional amp.

 

[mefferz]

I think you are hearing a difference simply because you are feeding more voltage to the DQ.

On my 8.4a Non-Alpine, I used the front signal for inputs into my DSP and I can tell you with certainty that it is a full signal as measured with a mic and REW.

Just as a comparison, when I was feeding my front mid-bass 75 Watts each, I did feel that my system was missing that full and powerful sound. When I increased the wattage to 200 to each mid-bass, it was a night and day difference and the system was now that full powerful system everyone wants to have.

It's been about 10 months or so since I last played with any setting on my system and it just continues to sound amazing to me and I get compliments all the time.

You are correct. After a few days of listening, I determined that the increase in voltage from the summing was tricking my ears. I was able to duplicate similar performance by disabling summing and simply increasing the output voltage on the DQ. I've been tuning my system for months and got a bit excited when something filled out.

It's been a real battle getting my system tuned, but it's also been a learning experience. The DQ-61 is nice, but now I'm wishing I went with a more robust computer controlled DSP that has more bands and active crossovers. This was my first real car audio system so I didn't have a lot of experience to go off of.

 

[mefferz]

No experience with it as of yet but I will be watching the replies. I haven't started my audio build yet but I have the 8.4a and often wonder if it wouldn't be better to just go aftermarket and sell it. Only thing is getting factory options to work with aftermarket (backup cam, blu-tooth mic, Nav antennae). So chances are I will probably be keeping the 8.4a and be going about it as you have and summing the signals and tuning. Glad you were able to find out at least that us without the Alpine system still need to sum the signal. I too was under the assumption we did not need to do it.

You should be fine with a LOC/processor that does not have summing. I was wrong in my initial assessment. There are so many variables in car audio (especially when trying to work with OEM head units) that sometimes you end up chasing ghosts.

 

[troutspinner]

You are correct. After a few days of listening, I determined that the increase in voltage from the summing was tricking my ears. I was able to duplicate similar performance by disabling summing and simply increasing the output voltage on the DQ. I've been tuning my system for months and got a bit excited when something filled out.

It's been a real battle getting my system tuned, but it's also been a learning experience. The DQ-61 is nice, but now I'm wishing I went with a more robust computer controlled DSP that has more bands and active crossovers. This was my first real car audio system so I didn't have a lot of experience to go off of.

I used a DQ-61 in my last truck but got a little frustrated with it. I did think it was a good unit but I was using a stock HU on an F150 that left everything to be desired, it was just lousy sounding. My next step was to go to an aftermarket HU but I ended up trading the truck in soon after.

You can always add a DSP to replace the DQ-61

 

[mefferz]

troutspinner,

When you installed your DSP did you add any resistors between the uConnect and the processor? I've had reps from both Arc Audio and AudioControl say it's a good idea to add 30 ohm 5 watt resistors between each positive and negative speaker wire pair coming from the uConnect to any aftermarket processor. Apparently this is supposed to mimick the constant load the stock speakers had. It prevents system "instability" like the system not turning on/off or signal cutting out, but I haven't had those problems. I'm not sure if the resistors would actually affect sonic performance.

 

[troutspinner]

I have not had any issues with mine. I could understand why those reps said that though as other Uconnect radios have had load issues. The 8.4a and 8.4an (non-alpine) just work, run with it.

 

[Otto]

This may be a dumb question, but what about the parking sensors and hands free phone? Does it play well with the summed signal and dsp?

Sent from my SM-N920V using Tapatalk

 

[troutspinner]

This may be a dumb question, but what about the parking sensors and hands free phone? Does it play well with the summed signal and dsp?

Sent from my SM-N920V using Tapatalk

Yes it does play well. The DSP is just processing the audio after it leaves the radio if you will.