Ok, this will be a small rant followed by a more constructive question or two.

TRYING TO GET THE PHASE AND TA RIGHT IN MY CAR IS DRIVING ME CRAZY!!! My head unit has the ability to change the phase on each type of driver (tweet/mid/mid woofer/sub), but only both at the same time, not left and right. When I change the phase using the head unit, it sounds different to physically changing the +/- of either driver at the amp. So which is ACTUALLY changing the phase? Do I need to try each set of speakers at all combinations of +/- connections to see which is best?

Also, TA. I've read many different ways to TA. I have a HX-D2, which measure TA in distance (mm). Should I:

Measure distance to each speaker from my head, and use that.

Measure the difference between the closest driver and all others, using the closest driver as 0mm.

Measure the difference between the furthest driver and all others, using the furthest driver as 0mm.


I've tried all three methods, and none of them seem to work particularly well

Also, I have tried different positions for mids/tweets before all of this stuffing around, so I believe I have the best physical position I can get for the drivers.

Thanks guys

what you trying to achive with the TA?

how well do you know your HU?

wait till it's dark, have a couple of drinks (not to many, seen you pass out before) get in the car and get into the TA menu, close your eyes and do it all with your ears

this is how i setup my Xovers

I'm trying to improve staging and imaging fudd I know my headunit very well. I can hear a difference when I change the phase, but not a better/worse, just 'different'. Maybe I should go back to my old mid-range... these may not work well with my other drivers :|

I'd put ALL speakers in phase at the amp and the headunit.

I'd then set up a datum, ie move your headrest/seat back foward until an arbitrary point on it is sitting roughly in teh centre of where your ears would be when in the sitting position. This makes it easier to retain the common point when measuring.

Measure the distance from the SAME point on the head rest (between your ears in listeneing position) to EACH driver and take note.

Which speaker is the furtherst away from your ear? Sub? LH mid or LH tweeter? This will be the speaker you need to 'dealy' all others to match. Subtract each speakers distance from the furtherst one and use this measurement as your setting for TA.

IE is your LH mid is 1300mm, LH tweet 950mm, RH mid 900mm, RH tweet 600mm, and sub 1200mm, then you will put the follwoing settings for each driver.

Your LH mid is the furtherest, so subtract from it, ie, your RH mid, will need 1300-900mm = 400mm delay for inphase sound to reach your ears at the same time as the LH mid.

RH mid :- 1300-900 = 400mm
RH Tweet :- 1300-950 = 350mm
LH Tweet :- 1300-600 = 600mm
Sub :- 1300-1200 = 100mm
LH mid :- 1300-1300 = 0mm

If your sub is the longest, you will need to use it's value as '0' and work from there the same way.

This will get you 'ball park' then I suggest you play a mono track and play each pair of speakers seperately ie Tweets, then Mids and ensure that the sound comes from the centre of the stage.

I have also recently been playind around with level's differing from left and right, as well as mid to tweeter. and have for the moment, found I prefer the RH tweet to be 1dB down in level over the LH tweet.

Level matching between mids and tweets and phase matching will come after you've set the TA and crossover. I've found I prefer all my drivers in phase.

The above is only based on my experience, it may or may not work for you...

I'll give it a shot BMWTurbo - was this how you set up the E30 or the E32?

hmmm....I like the description, however in the manual for the HXD2 it says

"press the up or down button to set the distance from the speaker to the listener"

and thats all it says

so the question is, does HXD2 do the above calculations for you, or can you follow BMW's instructions?

Also, Timmeh, do you have a 2 way or 3 way front stage? I assume 3 way..

so, set all your speakers in phase electrically (ie wire them in phase).

then, set time alignment either through BMW's way, or by measuring (i've tried the measure and input the distance trick too, and it doesnt do much for me either).

then, wire your midrange speakers out of phase with each other. This should increase crosstalk and provide you with a more precise, stable image. I think.

The way I set time alignment on my old HU was to use the "tic tic tic" track from Chesky 10 on repeat, then use small changes in time alignment from the above settings to move the image to exactly where I wanted it for each speaker band at a time (using the mute function on HX works well here, or you can pull the RCA's out at the HU). Then try Fudd's trick to finish of beers and tuning in the dark.

if that works, let me know so I can give it a go!

E32 The E30 is an empty shell atm. Steering away from putting a stereo in the E30 a bit now.

Matt VIP, I've nevere used a HXD2 so my method might not be suitable...

"press the up or down button to set the distance from the speaker to the listener" Would suggest it will calculate it for you from the actual distances.

As mentioned this will give you a 'starting' point. You might find that by delaying the tweeters/mids a bit over the mid basses you can add some depth.

yeah, I read that in the manual too Matt - but because it didn't seem to improve anything, I was wondering whether I was missing something. I'm going to try it the other way, and see how it goes.

Also, do you only have one single speaker connected when setting TA? Or each set?

nope, work with one set of speakers at a time - ie tweeters (with all else mute), then mids etc.

Im going to try both methods (ie calculation method vs plug distance in method) and see how I go.

but the midrange out of phase trick works well - give that a try

I think you're making it harder then it needs to be.

Phase is absolutely the THIRD thing you need to worry about. TA is around 4th/5th-ish.

Level setting is by far the most important. This can ONLY be done correctly by using a DMM....

Now set your crossovers. Do it based on response curves for your drivers, as a start. Cross over an octave away from rolloff. Slope should be 24dB at this stage.

Wire all your speakers electrically in phase. If you cannot flip the phase on one speaker in a pair, have a look over at TalkAudio, for I've seen a quick electrical switch that you can hook up to your speakers to do it for you. You need to be in the chair for tuning (unless its via measurements <- which, lets be honest, is far superior)

Play a mono track of something familiar. I've got one with Bongo drums, but there are others out there. Put a dot on your windscreen (white-board marker) where you want the image to centralize. I actually use an upside down CD on the dash, and look at its reflection.

Tweeters first. Then Mids. Then Midbasses. One at a time and mute the rest. Flip phase until you get something fairly central. Write it down. Then Tweets/Mids, Tweets/Midbasses, and so-on and so forth. Then left Tweet/right mid, etc. etc. until you have a nice little combination. Combine them all, and you have acoustic phase relationships. Wire up accordingly.

Now play with slope. Listen left only, then right only, muting all speakers that you're not actively listening to (such as MB if your Xover is the Tw/Mid). Find the best audible result (again, Measurement systems kick arse here, but alas, cavemen play with stones!)

If you dont have a coherent stage and image at this point (ignore depth), then your speaker locations are rooted. TA will not help you.

Only TA after you've done all this, and you wish to cement the stage, not create it.

Parallel first. Tweeters to mids to midbasses to sub. If you're an Alpine, its distance from furthest. If you're Pioneer, its distance from listener. God knows what the others are, but RTFM to confirm. Only Delta align (left to right) as your last step.

can we sticky that please admin?

cheers ~thematt~

whats wrong with the imaging at the moment Tim?

have you tried physicly TA'ing the speakers?

the silly bugger did something stoopid.... *tells timm3h to stop leaving remote lying around*


i'll let him explain, but was funny...

uh ohhhh...

do the words "timm3h!?!?!" "reset button" and "you idiot" feature in this story of woe?

not the reset button part matt..

I'd like to know the story to this..

Ok. I'd been messing around with the mids/tweets, because they were the ones I'd physically moved. What had happened was that my right mid woofers TA had SOMEHOW increased from 90 ish cm to 250 cm. It made a HUGE difference, and made everything else sound weird and outa phase I guess I shouldn't be surprised. when you've got one driver set to almost twice the distance the furthest driver is, ITS GONNA SOUND WEIRD HAHAHAHAHAHA

I suspect I put something on the passenger seat (where remote generally lives) and its changed the settings at some stage. Its sounding MUCH better now

One other thing. After I found this out, I reset it back to the correct setting, and played with the mids and tweets again. I set the TA in three different ways.

1) I set all speakers to the difference between the CLOSEST driver and my head.

2) I set all speakers to the difference between the FURTHEST driver and my head.

3) I set all speakers to the distance they are from my head.


Option one just didn't work - everything was WAY over to the right.

Option two was significantly better, but over to the left a little.

Option three was the best, but still not quite right (still to the left a bit) - probably because of reflections somewhere. a bit of EQ and balance tweaking seems to have centered it up though!!

how do you tweak the balance timm3h?

<<<is geussing he turned balance to the left, which decreased output from right speaker and centred his image...hmmm why doesnt everyone in non pro classes use balance instead of TA ?

I'm geussing ppl think its better to think your a rocket scientist and get bogged down with technicalities than just twist a balance control and just do it ???

seriously the number of cars I have judged in am classes who could have just tweaked balance to improve staging rather than messing with TA amazes me. Its not that hard ppl...unless you want it to be.
KISS seems some how relevent
peace
Cyberpunky

^^^^^^^^ shhhhhh dont tell everyone all the secrets

totally agree with you 'Punky. I was wondering how Timmeh did it 'cause we have the same headunits. In my last Pioneer, I was able to vary the gain for each speaker (ie L+R tweeter, L+R mid etc) to move the image to where I wanted it.

However, the HXD2 (as far as I can tell) only has balance, which affects all speakers in my front stage. In other words, it seems a bit blunt. I was merely wondering if there was an option I didnt know about (only had it for 3 weeks) that was a bit more precise....

point taken about keeping it simple though

Yeah, you're right Punky - I simply tweaked the balance I thought about raising the EQ on one side, but considering the balance essentially does the same thing with a lot less stuffing around, I used that

A DMM wil not allow you to set the levels correctly, unless all the speakers have exactly the same sensitivity in the car.

phase (actually polarity) should be done in the speaker wiring, not in the head unit.

crossover points set, based on in-car response and cutoff requirements. If necessary, change speaker polarity here to get correct phase with crossovers set.

re-check level, centre image should be there, but not focussed.

TA if you need to, furthest driver at 0mm, and then all set as difference. The problem here is that on all systems I have tried, the TA is not linear. i.e. 12ms to 10ms (12-10=2) is not the same actual result as 4ms to 2ms (4-2=2).
Bummer, but true.

use your ears, not your brain.

Pulse-R I've found that when I change the TA by 0.1ms on the Eclipse HU I have that the actual TA delay on the speakers is literally 0.1ms. When setting up last week I could get the TA bang on by measuring from my baseline to the actual measured and then punch in the delay required and on the next test it would be bang on.

I've only used the Eclipse HU though, haven't had any experience with other brands.