Crutchfield Labs Video: Getting perfect sound in the car
Our car stereo proving ground, part 3
Jeff has worked in the car audio industry since college and has designed and installed hundreds of car systems. He spent a handful of years at Crutchfield, helping take our company to new heights. After a productive tenure with us, he has moved on to a new challenge, but his enthusiasm and expertise still guide us.
More from Jeff Fay
In Part 3 of our series: Jeff upgraded his speakers again, ran higher-quality wire, and added a processor to sculpt the sound. He had to modify the F-150's door a little to get the speakers to fit — but when you want the best, there's no need to let a little modification get in the way.
So welcome back to the Crutchfield Labs! We're doing our third installment in this big truck build-off. The first principle is, when building a system, that the system can only be as good as its weakest link. So we knew that the factory head unit had some problems, so we tested that and we proved that the head unit replacement is probably the first, best place to start with the system.
Secondly, we added a great amplifier. Now one of the reasons I chose that Focal FPS-4160 amp, is that's the same amplifier that we use as our reference amplifier in the Lab. And in our lab, we do extensive listening to many, many speakers. So I'm very familiar with that amplifier.
I could have built a system for much less with a different amplifier, but I wanted to use that one because then I knew that when I changed speakers out.we auditioned several ninety nine dollar speakers, then we ended up with a pair of DXI Polks, then we went to a pair of JL 5x7s that have an outboard crossover network, and finally I have put in what I would consider to be one of the best sounding speakers I've heard in a very, very long time if not the best sounding pair of speakers I've found for the dollar.
These are the Focal Utopia Be 165W-RCs. They use the beryllium tweeter, which is the same tweeter found on their high-end home theater speakers that range somewhere around a hundred thousand dollars a pair. The tweeter alone is probably the most unbelievable aspect of this speaker component set.
And the crossover networks are also very good. And the first thing that we've done here, is we've played them with the crossovers that came in the box off of one half of the amplifier, and then the next step we're gonna actually bypass that crossover network. We're going to actively bi-amp, so doubling the power that we feed these two guys, and then we're gonna use an outboard processor EQ system to really dial it in.
One of the first things you'll say is, "Wow. How did you get a 6-3/4 into a 6x8, 5x7 hole?" Because if you go to "Outfit My Car" at crutchfield.com, we tell you that this speaker will fit but it will require modification.
So the first thing I did was I built a template out of a 5x7 speaker, and built an ABS piece of plastic to bolt in here. Then I took a Dremel and I notched out right down here, so that the 6-3/4 speaker would notch out at the top and the bottom and fit in there snugly. It actually fit, pressure fit, very well. But then I sunk the screws in through the sheet metal in the back to give it a nice, rigid platform so we'd get rid of some resonance there. Today let's go ahead and get started and take a listen to see what we've done and see how much better we've improved the sound.
So we've got the new Focals in. We've got.I've used the EQ settings inside the head unit. And I've tried to put the curve as close as possible. In fact, it even got better than the JLs. And I think that has to do with the fact that they're a round speaker and a separate tweeter, and we have a little bit more control through the crossover network and things like that.
But mostly what I'm hearing.if you recall, when we listened to the 5x7s, the 6x8s, I was getting kind of a - the soundstage was really kind of centered along the middle of the truck. And now I'm actually getting a nice image that's way above the dash and it's pushed out pretty nicely. I don't have a lot of complaints in the way it sounds right now.
It sounds really darn good, but I did run two sets of 12 gauge speaker wire to each, through each door, and I'm sure had I done that and left the JLs in they probably would have sounded even better. But I'm gonna bi-amp these next and we want to see what the sound does. The beauty there is that we're able to get that beautiful curve and that waterfall that we're looking for at full volume. And so that's really the magic here. It's not about did the curve look good at the beginning and now does it look better - the fact is, it's getting better and better every time, but it's also, and more importantly, getting louder and louder every time.
So that when I want to hear music and really get that visceral impact and that experience of being in the music, I can get that kind of concert feel and have the volume, and still get a great curve. So I'm gonna turn it up, give this a listen and we'll kind of evaluate what we've heard here so far.
Okay. So we've taken the Focal crossover networks out of the equation now. We've actively bi-amped everything, so that means that we're running, the tweeters are running, off of two channels of the four channel amp, and the midrange are running off of the other two channels. So again, bi-amping is something that's, really can make the system sound great.
However, let me caution you. Bi-amping is not for your everyday do-it-yourselfer. You have to have a lot of experience with sound tuning, with crossover points, and understand how those work before you really tackle something like that. So I don't really recommend bi-amping unless you're gonna buy a quality processor, you know, something like a CleanSweep from JL, or maybe an AudioControl piece - certainly lots of different products in there - the Matrix piece is a great piece.
In this vehicle we used the new Alpine processor, which is the PXA-H800, and the RUX-C800 as well. And what I did was I actually mounted it down in this little pocket and I left the umbilical on it, so that I could do two things. One, the processor's hidden away and of course I don't have a lot of space in the truck, so we kind of buried that. But the cool thing is this allows me to take this and actually hang it outside the window so that I can do all of my equalization while I'm standing outside the car, checking out the RTA.
Now some purists might say it's even better if I did it when I was in the car, but it hurts my ears, and I don't want to do that. So it's not safe. I want to make sure that I'm protecting myself so that I can continue to listen to great music. But the point here is this is a 32-band by 8 channels, 8 channels of time correction.
It actually has, for you do-it-youselfers, a really cool function where it comes with a microphone and it has the Audyssey technology which is found on several of our higher end home theater receivers. And it'll measure the acoustic response of the vehicle. It'll measure reflections of the vehicle, and it'll actually pre-set your EQ for you and then it will allow you to also log in with some software on your PC to kind of set your own target curve.
So now we have the factory, or the head unit, set to factory flat defaults. We don't have any time corrections set. We actually haven't done anything inside the processor yet. And I'm giving it a listen just to give an idea of what it feels like, or what it sounds like with the bi-amping capabilities going - certainly more impact, certainly a lot more volume. I'm noticing a lot more volume. So I've effectively doubled the power and therefore I should expect a lot more volume.
When we put the SPL meter in here we actually saw sustained levels with the pink noise already at like, 104 to 106 with peaks up to 114, which is pretty much like THX theater-level capabilities. So that's really exciting because I tend to like it loud and I like to rock out occasionally, but I like it to be clean and loud, and that's kind of the difference.
So the next step is going to be to go outside and take a look and we'll put it to the test, but I'm going to do some measurements in here. I'm gonna set my time correction, and time correction is really crucial to changing the way the soundstaging works. What I'm noticing right now is that there's still, you know, it's a very good blend across the front, but I'm definitely.I'm getting a little more left bias, purely because it's all flat now. So the first thing I'm gonna do is move these speakers out, I'm gonna move them out in time, if you will, so that the arrival of the music matches from both left and right.
And I can do that with each individual channel on here so I can actually move the midrange out differently from the tweeter, and I can move those guys. I don't move those because those are the furthest ones from me, but I can move the subwoofer out in time as well. One trick, that even if you have just a basic head unit, and you want to use the time correction function on your head unit to trick your ear into thinking that the bass is more up front, is to push the subwoofer out, maybe an additional twelve inches in time. What this does is, I think, what it's doing is it's allowing the midranges to take some of the focus off of the bass and that music, or the subwoofer wave hits just a hair later and it kind of tricks the ear into feeling that bass from up front - so that's a pretty cool trick. My buddy Steve Brown at Alpine taught me that one, and that's a pretty neat one so give that a shot.
Okay. So now it's time to EQ the system, or set the system up. The first thing we need to do is really set the levels. So the first thing I did was, I set the head unit to the clipping point using the RCA outputs. I used an oscilloscope to determine that point, and that point happens to be at about 30 to 31 on the head unit. Then I set the gain outputs on the amplifiers and I could hear, or see, on the oscilloscope where each one clips so we set those levels.
Now I'm using the controller, and I can actually go in here and set up each individual crossover point - go ahead into sound field adjustment into crossovers - and I can set the crossover points. In this case, I'm setting these tweeters pretty low because they're designed to play pretty low. I'm actually going to set the tweeters at 2.5 kHz. And then if I hit the channel button, you'll see I'm crossing over my mids at this point.
We're going to try it like this, but I'm gonna cross them over really low, down to 50. And then I can change the low-pass filter for the top end of the mids at 2.5, and then I'm gonna set those at 18db slopes for both the tweeter and the midrange. And I can go back and adjust this at any time. But the coolest part is, that I can actually change the gain for each individual channel, and now I can actually split this out if I hold down the channel button here.
Now I can go left or right or left plus right. So I can actually adjust each individual midrange, tweeter, the subwoofer, and change the volume through the processor without having to re-touch the gains on the amplifiers. And now it's time to adjust the EQ. And so I can again adjust them whole together, so left and right together with the midrange and the tweeter, or I can change that to be left plus right, so left or right or left plus right. And now I can adjust the left front speakers independent of the right front speakers.
And what I like to do, just to try to get in the ballpark, is I like to listen to the, I like to turn off, or unplug the RCA outputs from the right front speakers and the subwoofer, and simply adjust the left front speaker independent of the rest of the system. And that gives me a pretty good idea of what the curve's gonna be. Then I do the same thing on the right. Then I take those off and just do the subwoofer. And if I do that right, then I should get something that looks pretty good.
This is actually what the speakers looked like with some basic equalization from the head unit, and this was when we had the passive crossovers from the Focal hooked up. Now what I've done is bi-amp them, and I spent about, probably about forty five minutes tuning the system, but that's what it looks like bi-amped after I've EQed the system, and it's really a perfect curve. And in fact, when we dial it in you can see I've got a little bump here at 12.5k just like I wanted. It's hard to show that because of the resolution - we're at 3db steps here. Now at 2db and it still looks great. In fact, I'll spend more time to dial it in.
Wow! So what we're doing there is we're actually listening to what we did with the equalizations, kind of the before and after. We were able to instantly switch on and off what we adjusted, and it's night and day. I mean, for one, it's pretty impressive that these speakers - bi-amped, no equalization, just really super well-built speakers - can do an exceptional job of making it sound very good. But man, you just add in a little bit of equalization, some time correction, and it becomes a totally new beast up front.
And it is really impressive. When I'm listening to it now, you know, of course, I definitely get more soundstage up higher, but one of the cooler things is that I'm getting.all of the instruments have their own space in time out there. So, you know, while I'm getting that nice image that goes actually past the sides of the car, the other cool thing is that I'm starting to get these kind of like, bubbles, where the musicians are standing. And it really gives a good sound stage across the whole dash. So I couldn't be more pleased with the way this is performing.
You know one of the limitations to this system is the fact that the subwoofer is only a single ten, and you know when we look at our, an ideal curve, I wanted it to extend a little bit further. But this single ten is in a ported enclosure, and it's crossed over a little higher than that point where I want it to slope off. So when we look at the final curve, there's not quite as much low end extension as I would love, but I have to give something up because I'm fitting this in a super crew truck where I have to keep children and dogs and the whole family happy. So I give up a little bit of bass to make myself ultimately happy with the family's point of view so that they like me. And that's important too. But wow, the music performance is so much better.
What I'm hearing mostly now is I'm hearing music, and you know, you can build a sound system that has great sound. Sound, to me, is nothing more than reproducing, you know, stuff. And I don't want that in my truck. I know that I really like to listen to music in my truck, so I want to try to remove the electronics from the equation. And I think that, in my case, I've done a really good job of building this system such that I no longer really hear the electronics.
I've EQed the system so that the components are out of the way. The amplifier's out of the way. And what I'm really getting is that emotional tie-in to the music, and I can try to get that musicality and the way the artist really intended me to hear their music. I hope you've enjoyed building this system up to this point.
Again, we did this to build what we would call the penultimate system, so that now we can actually take things out, we can try different components in here, but first we're gonna do Dynamat so that we can really validate that, and we're gonna do three different steps along the way with the Dynamat. So that should be really interesting, and now I just get to go drive around and enjoy it. So thanks for being with us. This has been a lot of fun for me, and most of the fun is gonna happen after I get off camera and start jammin' the tunes. So thanks again.