Tuesday, January 25, 2022

Returning to Hapy Sounds - Part 2

I have spent some time improving the stereo set up in the bus when time has permitted. In a prior posting (See Returning to Hapy Sounds - Part 1), I described my effort to move the 5-1/4" speakers from the falling-apart door cards into small speaker boxes/pods constructed from a pair of schedule 40 4" pipe caps. These caps, now speaker pods, were attached to a removable piece of the vent system, so they are about knee-height and facing rearward. Today, I add another front speaker improvement.

Dash Speakers
image from FastFab
When these buses were first sold, there was a speaker mounted under the dashboard, pointing up at the windscreen, if you got the radio option. Regardless, the dash was constructed the same way, with perforations near the center of the dashboard top, a screw hole at the dash center-point near the windscreen and two mounting tabs underneath. While you could create something to hold a speaker, or a pair of speakers, leveraging the 2 tabs and the screw hole, a fabrication company already has. FastFab, based in La Hambra, CA, created a basic panel (product page here) into which a pair of 3-1/2" speakers can be mounted.

It should be noted, however, while the image on the product page, also appearing on the right, appears with rubber feet on the left side (which would fit into the mounting tabs), a mounting screw on the right side and speakers in-between... none of these are actually part of what you are buying. For $30US, you get a plain piece of bent metal with some holes bored into it. The product page does say that it does not include mounting hardware. However, in good faith, they could have included a picture of what you are actually getting. Simply, I was and remain unimpressed. I concluded it would probably take me more than an hour to make something similar and it probably wouldn't look as nice. I had it in-hand, so I moved forward with it.

3-1/2 Speakers
For speakers, I got a pair of 3-1/2 inch Kicker speakers. The model matches the 5-1/4 inch speakers I have mounted in the speaker pods I built in the last post, so the 3-1/2's should pair well. These cost me about $60US delivered, and they arrived with mounting hardware and wiring bits, but no grills. Since the dashboard has the perforations, and these speakers are going to mount inside the dash, grills are unnecessary. Crutchfield indicated on their website that these 3-1/2 speakers are an easy stock-swap replacement, where you re-use the stock grills, and that is why a grills are not delivered with the speakers.

I noticed that the panels had some sizing issues almost immediately after I started pairing the speakers with it. There are 2 misses: the mount holes, into which the black screws would ordinarily go to hold the speaker to the panel, are too large. So, the black screws which arrived with the 3-1/2 inch speakers could not be used. Second, the 2 large holes that the speakers are to set into are slightly too large. So, the speakers fit, but they shift around and will not sit cleanly without spending some time tweaking. When you combine these 2 design misses with the non-existent mounting bits, there is little actual value being delivered by these panels other than the bends and holes are in the right places.

Mount Speakers to Panel
speakers on panel
Unlike the picture on the product page, I chose to set my speakers through from the top, rather than suspend them from the bottom. This way, if one or more of the bolt/nut combinations fail, the speaker will not fall out of the panel. If I mounted it from below, loose fasteners could cause a speaker to drop out. Since the supplied black screws were not usable (panel holes too large), I found 4 gold-colored bolts in my home-electrical bin. These bolts had been for the copper grounding wire in electrical outlets. I had 4 nuts that fit, so away we go. As I mentioned earlier, getting the speakers to set just right them took some fiddling, but once they were set, and the bolt/nuts tightened, the panel was about ready for install. I like how the gold bolt heads match the gold centers of the speakers. In cases like this, it's better to be lucky than good. I added a couple of small pieces of foam on either side of the front mounting screw hole as well as on the mounting feet on the panel. This should reduce any vibration transmitting from the panel to the bus and vice versa. The foam on the feet became quite compressed from my use of clothespins to hold the foam in place, but they actually fit perfectly into the mounting tabs.

Dash Back to Black
Before I set the panel into the bus, I wanted to black-out the dash top. A prior owner had painted it gloss white, and that was the way it was when I bought Hapy. The glare on bright days was remarkable. So, when I replaced the windshield a few years ago due to age-related glazing, I painted the dash flat-grey like the rest of the interior of the bus. This was a considerable improvement, but there is a reason most cars have a black dash top: least daylight glare. I found a rattle-can of satin black in my garage, so after taping off the vinyl cover and the windshield seal, I shot what I could reach. There are areas that cannot be reached with a spray can, however: the vertical or nearly-vertical strips cannot be "seen" by the spray no matter the angle you hold the can. To get them color-consistent, I needed to hand-paint them with a short foam brush. This is kind of fun, actually. You can only see what you are doing through the windshield, so you blindly paint a little, run around to the front to see what you did and then repeat.

dash cover product image
I got to thinking about the noise in the bus, and how I want to reduce opportunities for sound to bounce off hard surfaces. The metal dash is a great example of one of those hard surfaces. So, after the painting efforts described above, I bought a DashCare dash cover. Knowing that the dash has contours to it, I paid the extra $5US for the faux suede, "DashSuede", rather than the standard thicker carpet model. This also "is low knap for a flat, low glare finish and will have high-low shading effects typical of Suede material". Once the sun returns, we'll see how "low glare" non-reflective it is. Since it has a thin foam core, it may help reduce reflected sound. I don't expect much, but every little bit helps. For now, this cover sits in a box, waiting for the projects to conclude.

Wire It Up
I stripped and prepped the wires before mounting the center panel. I figured I would have a hard enough time simply reaching the wires, and I was right. When I did the 5-1/4 speaker install, I knew I had these coming. So, I had spliced in a second stretch of speaker wire per speaker, so they were simply dangling when I brought the panel over. I simply routed the wire from the driver side under the dash and over the e-brake mechanics, dropping down into the passenger side foot well. In the picture on the right, here, I had the driver side wired in, using the passenger-side Sprinter seat as a work surface. Notice that the driver side is not installed yet. Still waiting... still waiting.
 
At this point, I had the wires and the speakers in a panel, so I simply I wired the speakers up: left -to- left, right-to-right. I suppose I could have tried to mix them up, but I didn't think there would be much left-right separation with the speakers so close together, so it didn't really matter. Either way, there are a pair of speakers pushing the left signal and a pair pushing the right. It is important to have all the speakers running on the same signal wiring to have the same resistance. Otherwise, sound levels will be inconsistent between them. By using the same manufacturer and the same series within that manufacturer, the sound will be as consistent as I could manage.

Mount Panel to Bus
Depending on how much crap you have under the center section of the dash of your bus, this could be anywhere from simple to very complicated. A few years ago, I had force-stuffed a rectangular plastic box into the original radio hole, and Hapy had some random wiring otherwise. I yanked the plastic box out, with a plan to do a better install later. Negotiating around the wires just took a ltitle patience. Once clear, the 2 feet set into the 2 mounting tabs towards the rear and the panel swings forward and up. I threaded a black screw that had delivered with the speakers through the hole in the dashboard and through the mount hole on the panel. I found that I had to start the threads on that screw first, and tighten down most of the way, before setting the feet. Otherwise the feet would pop off the little tabs. In fact, I got the front (front is front) screw almost all the way down and then swiveled the panel slightly to get the feet to set in the tabs. Then, I tightened that list little bit. As I wiggled the unit, there were no indications that the speakers were touching the underside of the dash.
 
Fire It Up
Once it was all put together, we were ready to test. As pronounced an improvement we realized when I moved the 5-1/4 speakers, adding the 3-1/2 speakers into the center of the dash was even more significant. The sound is very present now, with LOTS of mid and upper range, but the real test will be on the road with the noise of the engine, the drive-train, the traffic and the tires competing for our ears. Between the small 3-1/2" speakers and the very shallow pods for the 5-1/4" speakers, there was not as much bass as I like (I like a LOT of bass). I found that the head unit had reset while I had the power shut off, so the bass-boost was turned off during initial tests. Once I turned it back on and faded more signal to the rear, the bass came through and the bus is full of sound. Still, if you do something similar, it is reasonable to expect that the 3-1/2 speakers will push more high and mid than bass. I am looking forward to a road test to see if we lose the bass to road noise, forcing, perhaps, a sub into the mix.

That's it for today. Thanks, as always, for following along-

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