Modernizing the Stereo - Part 7 - THIS is what makes all the difference...

So all the hardware is now installed. Cleanly, might I add, and as a side benefit I was able to clean up and fix the mess left by others.  So does it sound good?

Cannot wait to go for another spin in this car! And this time with the full audio experience!

Well, I knew that the new speakers alone would be an improvement. Remember, a few months prior I had swapped out the door speakers for the Alpine coaxials, and it was actually pretty good, even using just the OEM deck (no external amp).

But now I have 6 very good speakers in the car - a pair of Alpine X-65C components up front and that pair of Alpine X-S65 coaxials in the rear.  I presumed all the high quality wiring and the powerful Audio Control d.6-1200 amp (at 4 ohm = 6x125 watts) with built in digital signal processor (DSP) WOULD mean good clean sound, but frankly I was not prepared for how a DSP can make a HUGE difference - even though I am choosing to stick with the OEM cassette deck (hooked up to the OEM optional Sony-made CD player).

Before I started this project, despite what I wrote in this blog, I was committed to keeping the OEM deck if possible, for aesthetic purposes.  To me, the OEM deck simply looks right.  So, no (more) fancy 21st century head units (plus I wasn't impressed with the Pioneer CyberNavi that had been installed by Worx).  And, my research quickly revealed that there are now a lot of products that integrate with the factory OEM head unit. With modern technology, the compromises inherent in factory head units can be vastly eliminated, and with modern cell phones I can get all of my navigation needs taken care of as well. So really, no more need for a 2 DIN stereo and the large display. Whatever stereo I use, I can focus on the sound quality. 

And this is why a DSP for me was a necessity from the beginning. Given however the lack of space in the car, an amp combined with a DSP was the only solution.  And, because this would be the first time I would use a DSP, I wanted something relatively simple to use, but sophisticated enough to actually add value by making a noticeable improvement in sound quality. 

My research revealed that there are some amps with rudimentary DSP controls on the amps themselves... but the majority of the current popular stand alone DSPs /DSP amps use bespoke software to make the necessary adjustments. 

As Pablo commented in an earlier post, the Five Star Car Stereo YouTube channel  (with Dean and Fernando) is a fantastic resource. The other notable YouTube channel is Car Audio Fabrication,  but Mark from that channel tends to be a bit too into certain brands (i.e. sponsored), while Dean and Fernando seem a bit more about installing what the customer wants (but centric to what their shop carries).  I also love their "911" series - I can totally relate to crappy installs that need to be removed and redone! Therefore, while Mark from CAF had a lot of interesting tips, I paid more attention to what Dean and Fernando talked about and demonstrated.  Thus when Mark recommended Audio Control, I was a bit skeptical (I've seen him act as their spokesman), while Dean and Fernando actively compared Audio Control against other brands, including Alpine, Helix, Rockford Fosgate, head units that include DSPs, etc.  

But in the end I was swayed by what both Dean and Mark said about ease of software use, which is why I went with the Audio Control DSP. The fact that their d.6-1200 product combines a 6 channel amp with the DSP was ideal, because I wanted to run the Alpine tweeters actively.

I'm not going to talk about the amp and its install because I've covered that in this Modernizing the Stereo series, nor will I talk at length about the features that the d-6.1200 has - stuff like AccuBASS (which restores bass the factory stereo removes), GTO (their auto-on feature), etc. - you can find plenty of reviews on the YouTube channels I mentioned plus elsewhere online.  I will mention however that I now have a USB cable tucked under the drivers seat by which I can hook up my laptop so I can use the DSP software to fine tune the d-6.1200's DSP settings:

Anyway, once the software was downloaded and installed, here is what the initial screen looked like:

I then began to tinker with the settings to get used to the software. It was also interesting to see how the music I was playing looked. Here is the Input View showing the RTA input from the OEM deck - you can see how there is a dip in the mid-range:

Then Output View:

It was here I started using the "auto" equilization feature (looking at the input and output RTA) in conjunction with playing back pink noise through the Sony CD player, in order to get the flattest output possible - important as part of OEM head unit integration.  Once output is flat, then a user can start tweaking to customize the sound to his liking. 

Another cool thing you can do with DSP is to measure the distance from your ears to the speakers - you can see below how I've entered, in centimeters, the delay distance.   I did this for all 6 speakers, both when I was in the driver's seat and passenger's seat. And yes I could immediately tell the difference, the sound seemed to come from a proper sound stage, with the vocals seemingly floating above the center of the dash, and instruments on either side!

I also have to mention that this amp has an options port, to which I hooked up this Bluetooth module through which I can stream music and/or use a miniaturized version of the laptop software from my phone. 

Finally, because the DSP allows for different settings, I installed this optional controller (so I can change on the fly) and hid it in my old ashtray (which had holes drilled in the back) - excuse the dirt/dust on the dash surround, I'll get that cleaned up in due course:

Current settings are for "driver", "passenger" and "streaming" but I will continue to tinker with the DSP settings - clearly I have a lot more to learn, plus I haven't really tuned the output to my ideal. But the music truly sounds fantastic - even though I am still using a flat curve! I've found that I can adjust for each song by using the OEM deck treble and bass controls!

Meanwhile I am debating whether to keep going and add a proper subwoofer (located in the trunk) or maybe a powered one under drivers seat?  I also worry - is the OEM alternator enough or does the addition of a fairly powerful amp require an upgrade? Anything else I need to do?

Oh, and while I was working on this, I did a few other things... standby for some more posts on those!

Yes, I Actually Had a Subwoofer Installed (For a While...)

Friends, some of you may have been surprised in reading my latest Speedhunters post that I had actually had a subwoofer, amp and custom made enclosure, which ended up getting thrown out by Nakamura-san at Worx AutoAlarm. Putting my feelings on that aside, I'd like to bring you all up to speed as to what I was doing in the audio department.

Long story short, yes I was working on a set up, but I wasn't ready to publish here on this blog until it was all done. And I had so many ideas that I was sure was going to make this the mother of all subwoofer enclosures!  But now that the cat's out of the bag... I won't spill all of my secrets and ideas, so this can be considered to be Version 1. Hopefully soon I can replicate and improve upon this idea.

Anyway - a few years ago I embarked on a DIY sound insulation project and actually while doing that, laid the plans for a subwoofer system. Because I had lost the use of the temp tire that is normally kept in the trunk due to the R35 calipers and rotors now on my car, the wheelwell was empty. Additionally, my research for how the R33 improved upon the R32 showed that weight distribution in the rear was important, and now my car was lighter in the back without the spare temp wheel!

So, installing a subwoofer would accomplish two tasks - it would restore or even improve the weight distribution of the car in the rear (assuming a subwoofer, amp and box would weigh more than the spare tire), AND if possible, I could utilize otherwise dead space where the spare used to be.

The first task of course was to get educated on car audio, specifically regarding how to build a subwoofer enclosure.  I quickly learned that each subwoofer has a recommended, ideal cubic volume for enclosure space, at which it sounds the best. I also learned that several well known manufacturers were producing "shallow mount" subwoofers - subwoofers designed to not require as much space but reducing the size of the magnet, etc.

Then after a lot of research on subwoofers, I chose the Alpine SWR-T10 10 inch shallow subwoofer as the best possible candidate for the job.

Not only was it compact so it would fit within the relatively short trunk in a flat position, it also appeared to have the lowest cubic volume requirements. This was important because, ideally I did not want to build more than I had to vertically above the wheel well, because I was envisioning the enclosure to extend all the way across the trunk area, forming a new floor. And I wanted to keep the floor as low as possible to save as much trunk volume.

Ideally, this new trunk floor would be level with the S15 trunk bar that I had also installed previously, so that I would have a perfectly flat floor all the way across.

With the Alpine subwoofer, I chose to match it with Alpine's PDX-M6 600W mono amp. Figured there would be no compatibility issues, at the very least.

So now, I had to figure out how to construct the enclosure.

As you can see, not exactly the cleanest space down there

The first trick of course was to find someone talented enough for the challenge - both to make a custom enclosure as well as to put up with my ideas. Through a friend I was introduced to a free-lance carpenter in Chiba.  He had no problems agreeing to the task, and so the first task was to lay out  some wood long enough to span the width of the trunk.  This wood was then made into a frame upon which we planned to hang the fiberglass mold from, and then cover up to provide a flat floor. And of course allow the subwoofer itself to be mounted flush.

I can't seem to find all the photos but will update when I do!

Anyway, once the ladder type frame was put together, using water and some garbage bags to verify the volume, we laid out fiberglass to create the unseen side of the enclosure, making sure it fit into the spare tirewell.

Hard to tell but the inside of the fiberglass provides ideal volume for the Alpine subwoofer.

I had actually asked another friend of mine (Alex) for advice on car stereo wiring, long before I started this project.  He swore by Monster, but since it was sourced in the USA it wasn't that expensive.

Love it or hate it, these worked well for me.

Alex (as well as the DIYMobile crowd) all recommended a fuse in line to the amp, just in case.

Another Monster product, ordered at the same time as the cable.

The biggest pain for me of course was to run the wiring connecting the amp to the back of my old head unit. You can make out the double bluish grey cabling on the lower left of the following photo.

Then it was just hooking up the Amp to the battery and the subwoofer.

Meanwhile, we checked the placement of the subwoofer and found some polyurethane foam.

Here is the speaker installed, with the grill on.

Speaker installed with the grill on. The surrounding polyurethane foam formed a flat floor on top of the box.

close up, you can see the Alpine R logo.

A shame I don't have a daylight photo of the whole set up. But, you can see the glowing blue Alpine amp to the left of the speaker.

I had planned some storage pods to try to use all available space as efficiently as possible. I never got around to doing that, however I can tell you that, even in conjunction with the cheapish Pioneer components in the car, the subwoofer really provided a much needed low frequency OOMPH to really give life to the music. Also, maybe because the amp was a source of clean power, compared to the current system (where due to lack of the subwoofer I have to really crank up the volume) which actually has more sound leakage at the levels where you can really hear the details in the music.

Anyway - looks like I will have to go back and figure out how to do this again. Maybe with the same components, but at the very least the search is on for a car audio shop that can do a great job with a custom subwoofer enclosure.  As usual, I will keep all of you posted!