Helix RTA & Auto EQ - A Car Audio Junkies Exclusive

[dumdum]

Does anyone have an FM curve file to use as a target curve?

Cheers

A fletcher Munson curve isn’t a house curve, a proper house curve will take how we hear into account

[Clintonl]

Is there a repository of different target curve files anywhere by anychance? Wanted to try a few different curves.

[Cutaway]

Is there a repository of different target curve files anywhere by anychance? Wanted to try a few different curves.

The Zazzi Rew Companion has a couple of different curves

[Chris E.]

It would be nice if some installers would post the house curves they used on specific cars and setups so that a "Library" could be created. The problem is that tuning is subjective for the most part, and different components and cars need additional tuning anyway, so just following a standard curve and playing around with it are probably your best bet. The best thing I have seen recently is the testing being done by Erin, he is testing speakers and posting the results, this is not subjective. Good speakers are very important in a system.
I have used the curves given in the Hellix software(ATF Ref.) , they are great starting places, eventually I boosted the bass up higher (+11db) and kept it flat from 200-3.2k, drop off to -5db up to 20k. My slope is much steeper from low to mid, the ref curve is more gradual. I am very happy with my bass response, but the mids and uppers need a little tweaking. Someday I would like to do a sound test and see how the steep slope sounds compared to the more gradual slope, on both the low and high end. this is the fun with car audio , the tuning never ends....

[Jdunk54nl]

Nearly all of the room/house curves come from Floyd Toole's (et al.) Research and where they curve needs to fall to sound reasonable. There is some leeway here, but for the most part all of the curves I have seen fall within that threshold, usually it is increased bass or decreased highs, which is within the threshold.

When I get home I will see if I can get a picture of where the curve needs to all from his sound reproduction book. This was discovered from many abx tests on what people preferred when they listened (subjective) and then gathering the objective data of what these speakers all had in common.

Link to the book, WELL worth the read:
https://smile.amazon.com/Sound-Repro...-no-redirect=1

[Chris E.]

Floyd's book is indeed a great read. Its one of the only books I seen that uses subjective listening tests and plots the data. I found a whole bunch of pics doing a google search. What I find interesting , is that the untrained listeners preferred a huge boost in the bass area. The thing I wonder about is, his data is based on using high quality speakers in a reflective room at home. The car environment is totally different, you may be able to get high quality speakers, but they are not aligned flat to each other (phase aligned) and the glass causes more reflections than a home setting. plus: road noise, engine noise, etc. This is why it would be great if some IASCA or other sound competition winners would post there curves, it would be great data since you have many people agreeing that it sounds good. Most are probably reluctant to do so, since they pay a lot of money to have a "competition tune" and would not just give away that information for free. As for the helix software, it would be great if the processors and software could dynamically tune the system according to the varying noise levels. Alpine had a unit years ago that said it could do it, but I don't think it was effective . We may not be at that level of technology yet, but it would be a game changer.

[Cutaway]

I like this blog post by Any on the subject of Target Curves and thought it relates well to this portion of the discussion A Note about Target Curves

[Chris E.]

Thanks for posting that blog post, Andy has excellent advice, I use his tuning methods. my house curve looks a lot like Andy's black curve and I'm happy with it.

[Jdunk54nl]

Yup, basically the same result Floyd got, As long as it falls within a certain boundary, it is usually acceptable to most people, with a little personal flavor added here and there.


I think a competition tune is just who did all of the stuff the best, as in who matched EQ between the speakers the best, and phase, and used high quality low distortion drivers (doesn't mean expensive), etc.

[Jdunk54nl]

That picture isn't quite the one I was thinking of, but still shows 90% of it. It was one where he had an area marked off, upper and lower boundary, and showed the different preferences, which were mostly in sub 80hz and higher than 12,000hz.