2 Seat Tunes

[Midway]

If using a modern DSP with PEQ, matching speakers is not necessary. You can 'adjust' the sound signature of any brand. Maybe that is a rule of thumb in home theater because most don't have a high end DSP so they want to keep sound signatures similar.

My dealer suggested using the same mid and tweeter as the rest of the front stage, said they have tried using a Morel Center channel with Dyn door speakers and found that the difference in sound quality of the 2 different brands of speaker would over power one or the other. Maybe the Helix DSP Ultra “RealCenter” overcomes this? Didn't really want to add a 3rd Dynaudio mid and tweeter set to my X6 build but am now leaning that way.

[Jdunk54nl]

I was thinking about the best way to describe a good 2 seat tune, then the home theatre receiver thread gave me how to best describe it.


Think about a home theatre,

If you had someone sitting in in every seat, and asked them to point to center, they would all point to the center channel. Same with right/left.
Sure, you optimize it the best you can for your listening position, but all seats can tell you those things and point to the same spot.

I just sat in all of my couch/chair seats and every seat the center was in the same spot, left was in the same spot, right was in the same spot. Volume changed and my EQ changed because it wasn't optimzed for those seats, but they were all clearly defined.

Throw on some music and use one of the decoders and the same happens for music in your home theatre.


I really think if you could have a good center, left, and right for all seats, that would be good for a 2 seat tune. There will still be compromises and optimization for your listening position, but all will sound better than they did. Andy's car was just crazy with how all of the seats sound great. I don't know his magic but it took a one off custom DSP/AMP and VERY specific install locations.

[blockrocker]

The home theater is a good analogy, I'm still racking my brain about your last post on deleting left/right information out of the channels. Is it done with EQ or input/output signals or what? Haha. I won't sleep tonight thinking about it. ;-)

I have never met Andy or know anything about the guy, other then he is the Audiofrog founder and is clearly one of the most respected people in the industry. So, I'm curious where one would get a chance to listen to his car. Is is his daily driver or a show car for the company? Does he bring it to events or give demo's? Are there pictures of his build or videos of the system in action? I've got endless questions, but would love a chance to hear that car.

Everything I've heard about him has been so positive. It would be cool to pick his brain or just listen to his opinions on everything car audio.

[Jdunk54nl]

Here is a good starting point
https://www.diymobileaudio.com/threa...ix-dsp.307730/

Basically if we invert the polarity then anything in common with both speakers gets deleted. One sine wave will be positive, one will be negative, and they will sum to 0. That gets you all of the common stuff gone.

The tricky part and issue again is now taking that sine wave that is +L and -R (it keeps all of the just -R stuff too) without all of the common and only playing the +L on the left side and the R on the right side. That is where the algorithm comes into play and can process that.

In theory, getting just the common stuff can be done via the above (see what gets deleted and that stuff goes to the center), Getting the +L stuff and +R stuff seems "easy" too as you can separate the +L and the -R back out with out all of the common stuff and flip the -R to be +R...that just takes A LOT of real time computing to analyze all of those signals and make sure they go to the correct spot.

Also* Andy takes his car to a lot of SQ events...at least he did a few years ago when I first was getting into good quality audio. He brought it out to an event that Handcrafted Car Audio in Phoenix was hosting.

[chefhow]

Ive been lucky enough to listen to Andy's, Natan's and Marks cars and ALL of them are exceptional 2 seat vehicles.
Andy and Natan use proprietary software/DSP's to do a lot of the work for them, Mark's car was purpose built to be a 2 seat car and sounds better from the passenger seat then the drivers seat at times.
Mark built the system in the NASCAR and then built the car around it so the drivers are in locations with techniques that make 2 seat sound possible. His L/C/R are all where they should be but in a way that is mind blowing.
95% of todays 2 seat competitors are not designed to be 2 seat cars, they take a 1 seat tune and work the tonality part of the score sheet maximizing the drivers seat and passenger seat for tonality and then take the hit on imaging and staging.
If you get a chance to listen do so but dont be surprised when they sound mediocre at best from the right side of the car.

[blockrocker]

Why not do both a driver optimized and a two-seat optimized tune? That is what I am considering using the new Helix Ultra DSP and a URC.3 to toggle between the tunes.

Is this a realistic option?

One thought I also had if using the center channel tuning capabilities of the new ultra, is it important the center channel have the same components as the FR/FL stage? If tuning the center channel is similar to rear fill it may not be necessary. I ask because matching speakers is always highly recommended when adding a center channel for home theater. That is assuming the front stage components fit in the front dash.

Yes, the long term plan is to get a director for my dsp.3 and have several presets tuned for different purposes (competition eq, high volume eq, bass demo etc.). In fact, I know it will give me the chance for a passenger seat tune as well. Then I don't have to switch seats for a demo, just change the preset. Personally, I'm not ready for a center channel in my system, I'm still trying to master the left and right.

I'm just curious if some of the "next generation" dsp's are going to go in that direction. Personally it seems like a no-brainer, if I can get a processor that can give my passenger the same level of enjoyment and experience out of my system that I do, without compromising a competition level tune, I would jump at the chance. However, I know a crap tonne of customization needs to go into the installation of such a system too, so trade offs I guess.

[Jdunk54nl]

Here are some good videos on Andy's car. The first one is better.

https://www.youtube.com/watch?v=Hf5POoa_axI

https://www.youtube.com/watch?v=r5xf6W_h1zw

[blockrocker]

Thank you chefhow and jdunk! Both great replies. The theory is incredible and clearly there needs to be a holistic approach take to a build like that. As both eluded to, it seems equal parts extreme install and extreme computing/processing power. Not to mention some pretty sharp minds controlling the entire process. I'm going to do my best to sit in as many cars (stereo) this year as possible. There it is, my new years resolution!

I might have to shoot Andy an email and politely ask when/where he may show his vehicle off this summer.

[JasonInAugusta]

The Camaro I built (with off the shelf stuff) would image and stage properly from both seats at the same time. It was A LOT like Natan's car. At SVR I had issues in the Camaro that were driving me crazy in the passenger seat. I got into Natan's Swift and heard the same issues. Told him about them.

By Finals we had both cars sorted out. They imaged and staged properly from both seats, didn't smear/drift.

We both lost. Judge in the passenger seat said they were both "confusing". *shrug

The Chevelle will be competing one seat, two seat, and SPL when done. RTA and install as well.

[blockrocker]

Here are some good videos on Andy's car. The first one is better.

https://www.youtube.com/watch?v=Hf5POoa_axI

https://www.youtube.com/watch?v=r5xf6W_h1zw

Dude - YES!!
I had to splash cold water on my face after watching that first video. Ha, that is my kind of sexy. What a killer stereo though, its great to hear how he plans to develop similar, more user and budget friendly versions of the dsp-amp combo. His two pet peeves literally took the words out of my mouth. Seems like a cool guy, if a touch terrifying in his wrestling mask. Not to mention patient....I couldn't get through 3 minutes of that second video. I simply couldn't understand the interviewer. I mean absolutely zero disrespect, but that was tough, Andy is a real pro. ;-)