Which Eclipse HUs have full adjustable digital time correction?

Absolutely.. If you know what you're listening for.. ie. critical listening for imaging, soundstage, etc. Once you hear a properly tuned setup with TA, you'll understand... Especially if you can hear it with then without or vice versa.

 
Absolutely.. If you know what you're listening for.. ie. critical listening for imaging, soundstage, etc. Once you hear a properly tuned setup with TA, you'll understand... Especially if you can hear it with then without or vice versa.
Ahhh I just noticed there is a formula for calculating the Time Alignment settings in my Eclispe manual.

I'll have to adjust mine and see if I can tell //content.invisioncic.com/y282845/emoticons/popcorn.gif.32dd9e22fd77e77bc3c907062768fcd2.gif

 
Hell yes it makes a difference. My girlfriend rode around in my car 'enjoying my awesome stereo' for 3 weeks before she got in the drivers side and realised her phasing/time alignment was totally ****ed on the passenger side. She's not an audio enthusiast, but after one track in the drivers seat...well, she makes me turn off time alignment when she's riding now //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif It can have a startling effect, especially if your installation is less than ideal (whose isn't?!)

Test it. You have pre-sets on your 7100 - open the PEQ screen and hold 1 for a couple seconds, that'll make your current setting pre-set 1. Then switch over to the time alignment and delay say...left by 2.4ms and right by 1.2ms. Go back to PEQ and hold 2 for 2 seconds. Toggle between the two and you WILL hear a difference....granted, those are random *** numbers and likely way off... but you'll hear it //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif

You can actually listen to the sound 'walk' across the stage in front of you as the delay increases. Just make sure you delay the CLOSE speakers and don't delay the farther ones even more //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif

 
To give you an example.. Phase between multiple drivers is the reason that your typical two way home speakers are precisely designed so that the sound from both the tweet' and the woof' hits your ear at the same time.. They're vertically aligned to be both the same distance away.. Impossible in the typical car. Also, in the "sweet spot"... You're the same distance from the Left and Right channels.. So a snare hit panned in center is one precise "pop" rather than a blurred pop from left then right.

If you've ever studied how waves work you can see when you combine same-frequency waves in perfect phase, they amplify to a perfect wave of the same frequency but higher amplitude (volume). If the waves are out of perfect phase, then the resulting wave is distorted and the amplitude at that frequency then is also adversely affected... So, what's that mean... At the frequencies where your tweets and mids crossover, phasing is important... At that point I guess you could say improper phasing can be called "crossover" distortion.

But also, with significant differences in distance, the closer driver will be sending sound to your ear sooner than the other driver, so it will significantly blur the sound image and wreck your sound-staging.

In layman's terms.. Just plain sounds better when the speakers are physically or digitally aligned (by delaying the closer speakers to compensate for improper placement in a car) so the signal from each hits your ears at the same time.

Clear as mud? //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif No pun intended

 
Good explanation Babs. I know what you mean about the sound waves. The technical term is destructive and constructive interference. If the sound waves are exactly one-half phase off, the sound waves will cancel each other out and you will not hear anything. That's how noise canceling headphones work //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

Now it would be really nice if you could specify a time delay for the tweeters too. Like you say, it is nearly impossible to have them exactly the same distance in a typical car. Since I have my tweets running off the same line as my midbass component and using a passive crossover, I know it would be hard to do from the head unit. The only way you would be able to do it is if the head unit let you specify exactly which frequencies to delay for each channel. That would be one badass headunit //content.invisioncic.com/y282845/emoticons/naughty.gif.94359f346c0f1259df8038d60b41863e.gif But we do not live in a perfect world, so I wonder is there external equipment you could add like the crossover boxes, that would allow you to set a delay for the speaker(s) on the line you connect?

headless, thanks for pointing the presets out. I honestly did not realize you could do that. You are definitely right, you can tell a huge difference. Depending on the song, I was able to hear the song walk while adjusting. It helps to shut the subs off too //content.invisioncic.com/y282845/emoticons/cool.gif.3bcaf8f141236c00f8044d07150e34f7.gif

 
Now it would be really nice if you could specify a time delay for the tweeters too. Like you say, it is nearly impossible to have them exactly the same distance in a typical car. Since I have my tweets running off the same line as my midbass component and using a passive crossover, I know it would be hard to do from the head unit. The only way you would be able to do it is if the head unit let you specify exactly which frequencies to delay for each channel. That would be one badass headunit //content.invisioncic.com/y282845/emoticons/naughty.gif.94359f346c0f1259df8038d60b41863e.gif But we do not live in a perfect world, so I wonder is there external equipment you could add like the crossover boxes, that would allow you to set a delay for the speaker(s) on the line you connect?
Just have to run active crossover from the head unit. I can adjust the tweets, mids and sub from my deck. works great.

 
Just have to run active crossover from the head unit. I can adjust the tweets, mids and sub from my deck. works great.
Well I am running the active crossover from the head unit, but I have the speaker setup on 4way+sub. If I set it to a 3way setup, I could do what you are saying, yes. But in that case I would not be able to adjust the front and rear channels independently

 
Now it would be really nice if you could specify a time delay for the tweeters too. Like you say, it is nearly impossible to have them exactly the same distance in a typical car. Since I have my tweets running off the same line as my midbass component and using a passive crossover, I know it would be hard to do from the head unit. The only way you would be able to do it is if the head unit let you specify exactly which frequencies to delay for each channel. That would be one badass headunit //content.invisioncic.com/y282845/emoticons/naughty.gif.94359f346c0f1259df8038d60b41863e.gif But we do not live in a perfect world, so I wonder is there external equipment you could add like the crossover boxes, that would allow you to set a delay for the speaker(s) on the line you connect?
Oh absolutely.. The phasing between front tweets and mids is very significant... This is probably why a lot of SQ setups are just front two-ways or maybe three-ways with time alignment to each individually.. Some head units will do a two way upfront such as the cd7100 or drz9255 or deh-p880prs or the cda-9887 coming out.. They switch to a three-speaker mode where (front tweets, mids and sub).. Basically I think you give up the rear fill, but for music only or non-surround setup, that's no biggie as your soundstage is upfront. Those head units have crossovers internally to go active with front components.. That's pretty much how that's done.

Pg 54 of the CD7100 manual calls it the Sound Adjustment Mode.. From 4 speaker layout (fronts, rears, sub), to 3 speaker layout for (front tweets, front mids, sub).

To do this in your case, you'd have to split that front line.. Have to have separate channels for tweets and mids in order to run separate delays and active crossover settings. This is my plan.. A four channel amp for front soundstage, and a mono sub amp.. simple system... just no rear fill... kill off the rear door speakers in my Forester. With the SQ coming from those fronts, I won't miss the rear fill. //content.invisioncic.com/y282845/emoticons/fro.gif.c695f1f814b01c4ad99fe7f8cccadd29.gif

... Oh, also, I think if you really had to go with rear fill's or a three-way, you can do this with processors like the PXE-H701 Alpine, or the JBL MS-8 coming out (processor that runs off OEM head units). Has to have enough separate channels for time alignment to each individual driver.. That MS-8 is a beast.. 8 separate channels.

 
Activity
No one is currently typing a reply...
Old Thread: Please note, there have been no replies in this thread for over 3 years!
Content in this thread may no longer be relevant.
Perhaps it would be better to start a new thread instead.

About this thread

grampi

10+ year member
CarAudio.com Elite
Thread starter
grampi
Joined
Location
Cheyenne
Start date
Participants
Who Replied
Replies
22
Views
1,902
Last reply date
Last reply from
Babs
IMG_20260516_193114554_HDR.jpg

sherbanater

    May 16, 2026
  • 0
  • 0
IMG_20260516_192955471_HDR.jpg

sherbanater

    May 16, 2026
  • 0
  • 0

New threads

Top