Pioneer P99RS time alignment question

[DubScientist]

Hi, all,

I have a JDM version of the Pioneer P99RS. Since it uses centimeters for the TA values, I've taken PL measurements in inches and converted those to cm.

But I've also recently come across the Tracerite TA calculator (that Eric uses on his website) and am now confused.. using the "is this a Pioneer setup" button shows me different numbers than what my inch - cm conversions give me (like a negative distance for my sub, which makes no sense).

Is there some secret sauce to the Tracerite calculator for Pioneer DSPs that I'm missing?

The numbers I converted myself seems to give me a good stage, though tonally it still needs to be dialed in.

Thanks...

[DubScientist]

Hi, wanted to add a post with the numbers I'm looking at to make my confusion clearer (and to say that I meant "Erin" not "Eric" when I mentioned the Tracerite calculator on his website, www.erinsaudiocorner.com).

My numbers using a tape measure and converting to centimeters are:

LT: 34" (86.36cm) / RT 50" (127cm)
LMR: 30" (76.2cm) / RMR: 51" (129.54cm)
LMB: 46" (116.84cm) / RMB: 57" (144.78cm)
Sub: 69" (175.26cm)

Here are the Tracerite number results for "a Pioneer setup" (and I'm assuming the numbers are in cm, even though the header for that section says "Settings in inches for Pioneer"):

LT: 120.33 / RT 136.41
LMR: 116.34 / RMR: 137.38
LMB: 132.43 / RMB: 143.43
Sub: 155.39

As you can see, the Tracerite numbers are pretty far off.

If the P99RS already takes your cm numbers and crunches them internally for TA purposes, shouldn't those numbers you use be the actual in car path length measurements?

Am I missing some background on this Tracerite calculator, and why it gives numbers that don't match up with straight-forward number conversion (inch to centimeter)? Should I ignore it completely and stick to my original measurements?

I understand this is an ancient HU at this point, so it's OK if I don't get many replies... but god help me, I've spent hours searching this site and DYIMA (shudder) for clear answers, and almost every thread I find is from at least 5 years ago, and ultimately devolves into falling-into-rabbit-hole territory of personal opinion, endless tweaking, swapping out components, etc.

And I still can't find a clear explanation of WTF is going on with this calculator, lol.

Thanks for any input...

[Notloudenuf]

Have you tried the tracerite measurements?

[preston]

I run a P99rs as well and have never done anything but measured from my head to the voice coils.

But all these numbers are relative - note that the delta of the tracerite measurements are the same as your measurements. I think what its trying to do is get your sub woofer to zero delay.

Either set of numbers will give you the same delay on all speakers, EXCEPT the sub. Remember the larger the distance, the LESS the time delay.

Using the automated time measurement system in the latest Helix software, I find that my IB mounted sub behind the rear seat has zero delay, even though its
about the same distance from my ears as the front stage which has anywhere from 0.1 - 5 mS of delay.
Maybe this is what tracerite is trying to do.

So enter your numbers, and pay attention to the sub sound, then enter the tracerite numbers and see if you get better sub response (more up front sub sound and possibly louder)

[DubScientist]

Notloud, I haven't used the Tracerite numbers yet, they seemed too whacky to bother with without knowing WHY they were whacky.

Preston, your idea of zero sub delay might be what they're all about. Using the numbers I made on my own, the center image is in front of me as opposed to the center of the dash, and the sub has also been a bit of a hassle to get integrated.

Thanks for both of your responses, appreciate it!

[erinh]

Hi, wanted to add a post with the numbers I'm looking at to make my confusion clearer (and to say that I meant "Erin" not "Eric" when I mentioned the Tracerite calculator on his website, www.erinsaudiocorner.com).

My numbers using a tape measure and converting to centimeters are:

LT: 34" (86.36cm) / RT 50" (127cm)
LMR: 30" (76.2cm) / RMR: 51" (129.54cm)
LMB: 46" (116.84cm) / RMB: 57" (144.78cm)
Sub: 69" (175.26cm)

Here are the Tracerite number results for "a Pioneer setup" (and I'm assuming the numbers are in cm, even though the header for that section says "Settings in inches for Pioneer"):

LT: 120.33 / RT 136.41
LMR: 116.34 / RMR: 137.38
LMB: 132.43 / RMB: 143.43
Sub: 155.39

As you can see, the Tracerite numbers are pretty far off.

If the P99RS already takes your cm numbers and crunches them internally for TA purposes, shouldn't those numbers you use be the actual in car path length measurements?

Am I missing some background on this Tracerite calculator, and why it gives numbers that don't match up with straight-forward number conversion (inch to centimeter)? Should I ignore it completely and stick to my original measurements?

I understand this is an ancient HU at this point, so it's OK if I don't get many replies... but god help me, I've spent hours searching this site and DYIMA (shudder) for clear answers, and almost every thread I find is from at least 5 years ago, and ultimately devolves into falling-into-rabbit-hole territory of personal opinion, endless tweaking, swapping out components, etc.

And I still can't find a clear explanation of WTF is going on with this calculator, lol.

Thanks for any input...

The numbers via my site are correct. They are large for a reason.

I start with the lowest possible delay in the P99 which is about 155 inches. And I work backwards from there.

You can sanity check this by simply looking at your LT/RT delta. Which in cm is ~40.4. Convert that to inches and you get ~16 inches. Which is the delta provided on my site.

Why do I do this? Because, if you want to use the 1/2 wave method for the subwoofer you will have enough "headroom" to do so.


Now, really, you can just enter the actual distance in and call it a day. The only reason you need to use my site for actual inches conversion is if you want to try using 1/2 or 1/4 cycle measurements. But I don't really suggest anyone do that anymore.

Hope that helps.

[DubScientist]

Appreciate your input, Erin! I'll give your numbers a shot. I never doubted their veracity, I was just wanting to understand WHY they were what they were, and you explained it.

Now, not to sound more noobish than I already do, but what exactly do you mean by "the 1/2 wave method" for my sub? Sounds intriguing.

Is it for getting low freqs to appear as if they're in the front of the car?

Thanks.