[clipto333]

Originally Posted by Bass&Trouble

You are referring to time alignment of the drivers on the same channel with respect to each other or time alignment as we know it in its common form as found in head units, processors etc where whole channels are delayed with respect to the farthest channel? Because the latter would be possible in an active system with crossover settings on the amp.

how is that possible? can one time align a driver with amplifier crossovers? are you talking about aligning the levels? or phase? you cant add delay with an amps(most of the amps i know) crossver. using a module is a different thing.

i would right away buy an amp if it is possible. let me know how.

one more thing. how does one test the accuracy of an inductance meter. i have an lcr meter which i doubt is accurate. and i dont have a known value inductor. any ideas or will i have to buy a known inductor?

[Gill]

Originally Posted by gunbir

One major drawback of an amp xo based active setup Vs an HU xo based one is time alignment. I only know of the Audison VRx series to have TA modules for the amps. There may be others but none that I know of.

I am bit confussed,can't one do the time alignement of indvidual driver in active setup through amp?I would love to know how the crossovers settings affect the time alignement!!Moreover in passive setup one can align the mid n low range drivers only,9887 has no option for highs alignement!

Cheers!

[navin]

Originally Posted by clipto333

can one time align a driver with amplifier crossovers?

of the amplifer crossover allows for TA you can. The point GUnbir was trying to make is that few amps allow this. Now he is refering to algning the woofer to the tweeter (in the same channel) sort of like is done for home audio either via electronics or by angling / stepping the baffle of the speaker.

Originally Posted by Gill

I am bit confussed,can't one do the time alignement of indvidual driver in active setup through amp?

when a tweeter is 20cm from your ear and the woofer is 400 cm from your ear one needs to delay the tweeter so that the sound from the tweeter arrives at the same time as the woofer's. this can be done via electronics (either passive or active).

[Gill]

Navin ji, Alpine 9887 allows F-r F-l,R-r,R-l and Sub in F/R/Sub system(4.2 channel).
So in this setup we can only align the Mid drivers and sub
where as in 3 way system it can be done in following mode Mid-L,Mid-R,High-L,High-R,L-Sw,R-Sw,L-F.
In this it will align the front High's n midbass n sub
SO acc to this it's not possible to do TA if one is running fronts three way active and sub.
Moreover if one is running the system active through amps,How will the HU control the alignement?

[DerAlte]

Originally Posted by Gill

Navin ji, Alpine 9887 allows F-r F-l,R-r,R-l and Sub in F/R/Sub system(4.2 channel).
So in this setup we can only align the Mid drivers and sub
where as in 3 way system it can be done in following mode Mid-L,Mid-R,High-L,High-R,L-Sw,R-Sw,L-F.
In this it will align the front High's n midbass n sub
SO acc to this it's not possible to do TA if one is running fronts three way active and sub.
Moreover if one is running the system active through amps,How will the HU control the alignement?

Gill-sab, in the HU, time alignment is done before frequency-segregation, since FS is optional (i.e. one can do it outside the HU as with passive 3-way).

As far as the 3 way is concerned, it is only routing the low/mid/high frequency range to the appropriate drivers. When 9887 is configured for 3-way Pre-amp output, it is only segregating what is given to it - the remixed signal after time alignment.

The same time alignment can be achieved if one can introduce the delays at the amps for mid and highs (outside the HU; without involving HU TA).

Sorry, I hope I have not landed up confusing you rather than clearing your doubt!

[Gill]

Originally Posted by DerAlte

Gill-sab, in the HU, time alignment is done before frequency-segregation, since FS is optional (i.e. one can do it outside the HU as with passive 3-way).
As far as the 3 way is concerned, it is only routing the low/mid/high frequency range to the appropriate drivers. When 9887 is configured for 3-way Pre-amp output, it is only segregating what is given to it - the remixed signal after time alignment.

Pardon my ignorance plz,trying to learn few things,By frequency segregaton you mean delivering the freq to proper channel or filtering the signal,
if it's delivering the signal then i got it what u want to say,otherwise far as i know TA is done for individual driver's frequency and that can be done if the crossovers n frequency are set for that driver!

[DerAlte]

Originally Posted by Gill

Pardon my ignorance plz,trying to learn few things,By frequency segregaton you mean delivering the freq to proper channel or filtering the signal,
if it's delivering the signal then i got it what u want to say,otherwise far as i know TA is done for individual driver's frequency and that can be done if the crossovers n frequency are set for that driver!

Frequency segregation = separating into low / mid / high bands.

TA is applied on all frequencies within a certain band of frequencies, not one specific frequency. It just coincidental that the band is the same for the sub / woofers / mid / tweets.

After TA is applied, it is left to the user whether to use n-way drivers or not. Fine if you are using sub + 3-way, will also work with 2-ways + sub. Will also work with full-range speakers also, but will give a funny effect (like listening to jag-rata 2 streets away)!

[Bass&Trouble]

Originally Posted by Gill

Navin ji, Alpine 9887 allows F-r F-l,R-r,R-l and Sub in F/R/Sub system(4.2 channel).
So in this setup we can only align the Mid drivers and sub

Partly correct. It does not just align "mid drivers" and sub. It aligns the whole channel comprising of the mid and tweet with respect to the other drivers as whole channels.

Originally Posted by Gill

where as in 3 way system it can be done in following mode Mid-L,Mid-R,High-L,High-R,L-Sw,R-Sw,L-F.
In this it will align the front High's n midbass n sub

Correct, but in this case, there will be no provision for doing anything to your rear fill. If you connect rears on parallel mid and high channels, your TA is now haywire.

Hence, I feel it is better to achieve TA of tweets with respect to their respective mids by proper placement, i.e. ensuring that they are equal distance from ear as the midbasses. If not, they can also be trimmed or boosted to compensate for them being closer or farther respectively, and use TA for whole channels so that fronts, rears and sub are all properly synchronized.

Originally Posted by Gill

Moreover if one is running the system active through amps,How will the HU control the alignement?

HU will just apply the time correction to the pre-out and the amp will provide the filtering function.

[Gill]

Is this possible:-
I run three way active through hu and run the rears from hu.and when not req the internal amp can be turned off and rear fill stops!Will the rear fill play the full frequency range for just BP freq,as in three way active mode the rear pre-out is treated as midbass which will have bandpass freq!
I am asking this as i plan to run just woofers in rear instead of co-ax.As woofer's will not pull the soundstage much towards the rear seat.

[clipto333]

Originally Posted by Gill

Is this possible:-
I run three way active through hu and run the rears from hu.and when not req the internal amp can be turned off and rear fill stops!Will the rear fill play the full frequency range for just BP freq,as in three way active mode the rear pre-out is treated as midbass which will have bandpass freq!
I am asking this as i plan to run just woofers in rear instead of co-ax.As woofer's will not pull the soundstage much towards the rear seat.

gill,

if you want rear fills, i think you should not go active. running the rears on band pass or what ever config will definitely affect the front sound stage. for the sake of sq, i think you dump the rear fills. but it my opinion and you need not do that :-) but honestly, even if you sit in the back the soundstage will remain in the front. and its not that bad. you can change the levels of the sub to balance out the sound.

i think 9887 has TA for every channle. you just need to add the distance and every driver willl then be aligned with each other. correct me if im wrong. what you can do is to route the rear using a switch parallel to the fronts. whenever you need the rears, switch off the fronts or let them run parallel. the sq will be affected though but i think you will be fine. i dont see any other way to use the rear fills.

regardin your query, i think the speaker levels will change with the preamps. if you apply a filter on the line level output, then the speaker level will also play with the applied filter.

correct me if im wron plrase :-)

cheers

[navin]

Originally Posted by clipto333

for the sake of sq, i think you dump the rear fills. but it my opinion and you need not do that :-) but honestly, even if you sit in the back the soundstage will remain in the front.

the big problem whe one does not have rears is that you are so far off-axis (to the front speakers) that the balance of the sound coming from the front speakers is just not right (besides the fact that there are objects like the front seats betwen you and the front speakers.

[clipto333]

Originally Posted by navin

the big problem whe one does not have rears is that you are so far off-axis (to the front speakers) that the balance of the sound coming from the front speakers is just not right (besides the fact that there are objects like the front seats betwen you and the front speakers.

but one cant use rear fills in an active system. i agree with you though but then there is no choice.

navinji how can one use rear fills in an active system? you must have experienced this kind of problems im sure. :-)

cheers

[Bass&Trouble]

Originally Posted by clipto333

but one cant use rear fills in an active system. i agree with you though but then there is no choice.

By using a seperate outboard active crossover, or using the crossover on the amps, or if you're really hell bent on using the head unit's internal crossover - by using a signal summing device.

[clipto333]

Originally Posted by Bass&Trouble

By using a seperate outboard active crossover, or using the crossover on the amps, or if you're really hell bent on using the head unit's internal crossover - by using a signal summing device.

so you don't want this discussion to go on? thats sad.

and no offence b&t but i replied and asked navinji something. why are you banging your head lol

[navin]

Originally Posted by clipto333

navinji how can one use rear fills in an active system? you must have experienced this kind of problems im sure. :-)

in the days when the Dipplodoccus and Triceraptos (Jurasic Age) roamed the earth we did not have HUs that were so sophisticated so we used outboard crossovers which then led the manufacturers to integrate crossovers into their power amps lets call that the Tertiary Age.

In the Quarternary Age Hus are quite sophisticated. I am not aware to what degree this is true. Do the HUs allow for 2way and 3 way crossovers for the front and rear channels? If they do do they have TA for each band of their 2 way or 3 way outputs? In theory anything is possible. After all XOs and TAs are now single chip solutions (with a few outbaord passive components).

In theory if you want to TA a channel (FL, FR, RL, RR, sub) you should do it BEFORE the XO and if you want to TA a band (HF, Mid, LF) you can only do this after the XO.

As far as rear fill goes yuo can always use the XO of an amp to go active.