[CaptainMorgan]

So I started talking about this in my door pods thread, but I figured now I'm far enough this deserves a thread of it's own.

This whole plan was dependent on getting a DSP to go active. For those of you who aren't sure what I mean, that's using a sound processor to apply the crossovers to the signal before the amps, and then amplify the tweeters and woofers separately. This gives you a whole new world of tuning possibilities compared to using off the shelf audio gear.

My awesome parents who still like to see my smile like a little kid on Christmas got me my miniDSP 2x8 with DigiFP I/O card. Here it is out of the box, just a big circuit board. Look at the RCA connectors on it for a size reference, it's almost as big as a typical amp.


I built a nice little box for it that I'll grab pictures of later that turned out pretty cool for a cheap and functional solution.

I built new RCA interconnects to hook this up to the amps. Nice dual shielded coaxial video wire, professional grade stuff. The DSP being in the trunk also means very short runs and not exposed to really any of the other electronics in the car by proximity. The DSP gets it's signal from a digital sound card in a laptop over a toslink cable.

Here is a sample image of what the software interface looks like. This page is where most of the action happens. The other tabs are activating the right inputs and outputs that you want to use and choosing the correct signal to go to the correct output.


Here is the routing page.


Here is an example of a crossover setup page.


Here is an EQ page. Every single input and output channel has it's own full parametric EQ, so you can correct on a per driver basis as well as a total system basis. This will let me correct for issues like reflections that are unique to the left and right sides separately.



I just spend a couple of hours tuning with the DSP software, wow is this stuff cool. When the laptop connects to the DSP all changes are applied in real time, so I actually could get a decent tune (without EQing) by ear. Mute all channels except corresponding L and R of same driver, and slowly attenuate the near driver down until the sound is coming from the center of the dash. Then do the same thing with the other drivers.
I really like being able to mess with crossover points in real time. I can actually tell very distinct differences in sound when I shift the crossover frequencies, even if only by relatively small margins.

One of the best parts is my noise floor is amazing. On a good audio file it's almost absolutely nothing, even amplified to ear bleeding levels during only vocals.

Now I need to get it to final install phase so I can actually enjoy it. Right now everything is just sitting in the trunk for testing and I need to run a wire to the IGN power circuit for the laptop turn on/power lead. It'll automatically boot up when I turn the key, and not stay on to drain the battery when the car shuts off (It'll hibernate after 15-20 minutes, that way if you're just getting gas or running inside it'll stay on for you off the laptop's battery).

I'll get a ton of pictures for you guys, but for now it's time for a break. I'll be back at it late tonight I'm sure.

[BatCaveTrep]

I'm sure it has been explained somewhere, but how is your setup configured? I've put bits and pieces together, and now you mention a laptop. I always assumed, when you mentioned DSP, that you would be using something like this, but I suppose you are; just in a DYI project? Is the laptop mainly for the DPS software? Interesting and I'm curious to see the final product.

[beeblebrox82]

so awesome.

[CaptainMorgan]

The laptop is the interface for programming the DSP, but I'm also running the sound system from a laptop that stays in the car. I don't have a screen in the dash ready to go yet to fully utilize it, but I'm working on it. I'm waiting on funds to get the last couple of pieces ready to go, time to get the savings back up first after Christmas bills. I need my new solid state drive for the laptop before I really bother with configuring the front end and all the software just how I want it.

The DSP I'm using is similar to something like what you showed, but more DIYer to it. It's cheaper but it comes more raw with you getting it set up more yourself. Looking at the Helix interface it looks to have just about all the same capabilities, just laid out differently. The biggest change I see is that it using a high number of bands graphic EQ where as the miniDSP uses a large number of parametric EQs.

Basically here is my setup.
Laptop (source unit) - miniDSP- 3 amps (Boston Acoustics GT-2200 for front woofers, JL 300/4v2 for tweeters and rears, and a cheapie Pioneer amp for the subs) - Legatia L6v2 woofers, ScanSpeak Illuminator D3004 tweeters, JL 8W0 woofers.

[paintballdude05]

Wow that's just over the top Dan! You really are an audiophile!

[CaptainMorgan]

I'm working on it.

I can't wait to put this on display for you guys at a meet. I'm shooting to have it 100 percent functional for Danlisle.

[BatCaveTrep]

Is the screen going to be an actual head unit or another DYI project? I'm assuming the screen with be your access to the laptop, since the laptop won't be sitting up front?

I take it your laptop currently uses SSD? It would be nice if it was possible to add internal SSD to laptops that don't currently use them.

I haven't messed with audio equipment in 20 years, I just remember during that time there were external DSP units that were used, such as Eclipse.

What's the difference between graphic and parametric?

Where are you planning to put the Legatia L6v2 and ScanSpeak? I have plans to upgrade my system, but when that times comes I'll seek your input.

[Scooter-Man]

Nice set of equipment and those door pods. Now for the fun stuff, spending the next 8 years dialing it in. In car audio, it never sounds 'good' enough.

How many bands per channel of EQ does the mini-DSP have?

[CaptainMorgan]

Five bands parametric, which should be plenty with how adjustable it is.

Considering that when eqing on a per driver basis you only have to consider the frequency range within the crossover points I doubt I'll need more.

I'm going to have it dialed in much sooner than that, I'll be putting together an RTA setup very soon to be able to do high level tuning. I hope to have it well before the meet and I'll gladly bring it to tune other people's systems.

[CaptainMorgan]

As promised here are a few pictures. It's still obviously only semi installed, but it's getting there fast. The wires are now all dressed to the bottom of the computer/DSP board, but past that they are still loose. I wanted to make sure I had everything working before I started running them under the other trunk sub floor boards.

Here is the DSP in case before it's all hooked up.


The digital IO card is attached to the top of the case above the main DSP board. I used some longer bolts, plastic spacers I cut out of spare material from the case.




Now here we are all hooked up for now.







In this semi installed state I don't have the touchscreen in the car yet. But my wireless keyboard I got for the car can control winamp within a playlist blind just fine for the moment.

I'm at the point where I need to remove the old RCA runs to the front of the car and the HU and run USB, IGN on power wire for a relay, and a video wire for the screen.

[CaptainMorgan]

Sorry, I missed your post on my phone when I looked at this thread yesterday.

The screen is just a DIY - fiberglassing a bezel for it. I started before but sidestepped into getting the sound up and running. There won't be a HU anymore.

This laptop doesn't currently have a SSD. It's just sitting on the old Windows install in a regular HDD, but I'll be dropping in a OCZ Vertez 4 128GB SSD in as the main drive. It's supposed to be pretty easy to do, but I won't vouch for that until I get it done.

A graphic EQ is what you typically see where you boost or cut bands of the frequency, and how much control you have is determined by how many bands the frequency spectrum is split up into. A parametric EQ is very different. On a parametric EQ you still define it's control level by how many bands it has, but each one is an equation with adjustable variables instead of fixed bands. You set what frequency the parametric filter is centered at, set how much to boost or cut, and then adjust "Q" to narrow or widen the effect of the filter. Instead of getting something that looks like a bar graph you end up with an EQ that is all smooth curves with the calculations being done for every individual frequency based on the equations you have altering the signal.

As far as the speakers, I started that thread a while back. The pods aren't done, but they're functional. I need to do the finishing coats of filler and sanding to get them into the final shape before painting.
http://www.dodgeintrepid.net/showthread.php?t=238775

[BatCaveTrep]

It will be interesting to see the DIY touchscreen. Good luck on it!

Awww, so you're converting it to use SSD? I never looked to see if it could be done and if so how easy.

I read the pod thread, but didn't know if those were the speakers or not...but now after rereading your parts list, I realized I had confused my own self with your list. I understand it now.

How adequate is the cooling going to be for the laptop?

[Patel.748]

I have got to see this in action...

Hopefully one of these days when I am not so damn busy!

[hrmwrm]

so, what format are you loading your drive with? flac? ape? wav?

[CaptainMorgan]

Flac right now.