Summing Alpine 8.4AN System?

[rpr]

Has anybody ever confirmed which high-level outputs from the factory amp you need to connect to aftermarket amps and DSPs to get full frequency response with the 8.4AN Premium Alpine system?

My shop just told me they used an RTA and got a full response from the high level outputs from just the sub, mid ranges and tweeters.

Hard to believe you don't need the woofers in the doors?

 

[rpr]

Well, I picked up the truck from the shop today, and it sounds terrible.

After replacing all the stock speakers with Hertz Hi-Energy, replacing the stock sub with a JL Stealthbox (W3), and adding two Alpine PDX amps and an Audison BitOne DSP, it is louder but barely sounds any better than the stock Premium Alpine system. I cannot believe this after spending $5K on the upgrade.

I have to think its a setup issue with the DSP, but this shop claims to know the Bit One inside and out. Could be the way they did the summing but they said they got full frequency response on an RTA.

The system has the exact same muffled boomy sound as the factory system, which is what I felt the DSP would address. Like too much bass is being directed to the the 3.5" mid range and 6.5" mid bass, and the gains may be off (doesn't really play too loud but still sounds like there is distortion).

Guess I need to learn the BitOne software and do a deep dive at the frequencies did not want to do that but not sure what choice I have.

Any good tutorials out there on the Bit One?

 

[troutspinner]

I would take it back and tell them it sounds like crap and have them fix it. You didn't pay that much to have to do work yourself.

 

[Dubstep Shep]

Yep. Tell them to fix it or give you a refund. Most shops are full of idiots. I used to work at a car audio shop and I can't even begin to tell you how many screw ups we had to fix from other companies.

 

[charonblk07]

It may be incorrectly tuned for the components used, I would take it back as well. Even just playing with minor changes in the crossover points in my system would make a dramatic change in how it sounded. Make them tune it again and again until you're happy.

 

[rpr]

Problem is they are a 55 mile drive, in city traffic, and they did a crap job tuning it to begin with so I can probably continue to count on crap tuning with revisits.

I'm thinking it may be less frustrating, and more fruitful, to try to do the tuning myself.

Biggest problem is that I do not have an RTA, other than the JL Audio app for the iPhone. Do you guys think that is good enough to confirm whether they really did wire it up in a manner that is getting full frequency response, and to tweak the EQ curves?

 

[rpr]

...and I do have a feeling the crossover points are wrong, sounds like way too much bass in the Hertz 165XL's, they are very "boomy".

Also think they screwed something up with the rear fill, horrible muffled sound.

Not sure I want them touching my truck again.

 

[autokraftgt]

Thats a lot of money to be disappointed in the outcome.
You have nice equipment and it should put an immediate smile on your face.
Anyway you can post the crossover points? Slopes?
If not, have the shop tell you all the details of the system, then tell us.
Something tells me they set gains (prob incorrectly) and gave you a very generic tune.
This kind of stuff infuriates me

 

[Etroze86]

That and your doors my not be properly deadended and sealed to make the most of those XLs and I believe you need to summon all channels or at least on the older alpine systems in the 4th gens is what people did.

 

[rpr]

Well, just installed the Bit One software on the laptop and checked it out.

Unbelievable, the crossovers were ridiculous.

As an example, the HV-165XL's are rated at 40 Hz to 6,000 Hz.

They had them both set at 70 Hz to 300 Hz.

Just incredible, they should have known something was wrong the minute they listened to it.

I haven't played with the EQ, but man, what a difference.

Smiling now, and hope to grinning like a fool soon after some more tweaking.

 

[troutspinner]

Understand that crossovers should be set to audible crossover points and not necessarily what the manufacture has spec'd. You have a 3-way system, it is possible your mids are handling 300 up to whatever your tweeters are set at.

I don't know your experience with audio and crossovers and such but do be careful, you could blow something if you do not have a good grasp.

 

[rpr]

Yes, thanks, I didn't set anything near its extreme frequency response rating, but widening the respective frequency bands addressed the issue.

You are correct, they had everything over 300 going to the small 3" mids.

However, the small 3" mids (Hertz HL 70s) are no where near as capable as the larger 6.5" Hertz XL's, so by sending everything over 300 to the mids all you heard was the 70-300 response from the 6.5's, even when adjusting the gains. Hence, the muffled sound just like the factory system. Hope this makes sense.

I am treading carefully, I haven't played with car audio in over 10 years and it has changed considerably. I appreciate the warning.

Now that adjusting the crossovers has at least woken up the system, I need to do some research on methodologies for setting the gains and EQ correctly.

Having a 31 band EQ for each channel is a bit overwhelming (haven't touched that yet).