Straightening out the power cord tangle in vintage cars

Last winter, I wrote a series of articles about the history of obsolete audio, beginning with the home-sized tube radios that people originally shoehorned into cars, and continuing with in-dash radios, in-car record players, 8-tracks and cassettes, the invasion of power amps and big speakers, and finally, CD players. In the series finale, I discussed the pendulum swing that now favors keeping the original in-dash radio, and touched on some of the options that are available if you want to pump your own music through it.

Like my diminishing craving for speed and horsepower, my need for a constant source of high-wattage music isn’t what it once was. On long drives, I’m now quite content to leave the music off for hours and give my mind the quiet and space to do the shuffling and percolation thing that it desperately needs but so rarely receives. When I interrupt that quiet time with music, the way I do it depends heavily on which car I’m driving.

It wasn’t that long ago when I had both the GPS and the phone on the windshield, and the power cord configuration literally looked like this (although I’m letting the cigarette lighter adapter box dangle off the dashboard for dramatic effect.
It wasn’t that long ago when I had both the GPS and the phone on the windshield, and the power cord configuration literally looked like this (although I’m letting the cigarette lighter adapter box dangle off the dashboard for dramatic effect). Rob Siegel

Like many vintage cars, the 1970s-era BMWs that make up most of my herd are not known for their bank-vault-like quiet. BMW 2002s have frameless windows which, even when pressing against a new door seal, never seem to shut out the wind noise quite as well as the framed windows in larger cars. My most precious ride, my BMW 3.0CSi, is particularly egregious regarding wind noise, since it not only has frameless windows, it is a true coupe without a B-pillar. So the door window and rear passenger glass have to seal against each other with a single strip of rubber. Which they never do, at least not well.

I also should say that, for a number of reasons, I’m not a Bluetooth guy. Some of that is simply my personal automotive landscape, as neither my daily driver (2003 BMW 530i sport) nor my wife’s (2013 Honda Fit) have Bluetooth. But even when I have rental cars, I rarely employ Bluetooth. It’s not that I’m a Luddite. I was an engineer for 35 years and am quite comfortable with shifting technology. It’s a combination of other factors. For one, I just don’t talk on the phone a lot while I’m driving. Second, rather than using a Bluetooth-connected streaming service, I prefer leaving my phone to run Waze and using an old-school iPod with my personal music collection on it (yes, I’m aware that the phone can do both). Lastly, I have a strong and visceral dislike for interacting with display screens in cars. (I can hear readers shaking their heads and saying, “Yeah. Luddite.”)

For these reasons, when I’m road-tripping the 2002 or the 3.0CSi, I sometimes simply use my iPod or phone with ear buds, which also serve to knock down the wind noise (yeah, yeah, I know, there’s a legality issue). If I don’t do that, I need to employ a stereo that cranks out distortion-free sound which can be heard over the thrum of road and wind. The 3.0CSi has an integrated 1980s-style ADS power amp and speakers and an in-dash CD player with an aux port, so it’s all set. For the 2002, I use a Cambridge Soundworks Model 11 suitcase stereo which I power off the cigarette lighter. It gets crankingly loud, but I need to pack and stow it in the trunk at night.

On my cars with framed windows like my ’73 Bavaria and my ’79 Euro 635CSi, wind and road noise aren’t nearly as much of an issue. Both of these cars have unfortunately lost their original radios in favor of later ’80s Blaupunkt cassette decks. They don’t look period correct in the dashboard, but at least the combination of higher wattage driving speakers that aren’t 40 years old is enough to provide decent sound. So then it’s just a question of how to get my music source into the cassette deck when they’re too old to have an aux port. This question recently assumed renewed urgency, as I’m about to drive the 635CSi 2000 miles round trip to an annual vintage BMW event (“The Vintage”) in Asheville, North Carolina.

As I wrote last winter, there are a few choices for getting your music into an old radio. If it has a tape deck, you can go with the old-school cassette-aux adapter (literally a cassette-sized piece of plastic with an aux cable and a 3.5mm plug attached), but they don’t sound great, and visually you have an aux cable hanging out of the front of the cassette deck, which always reminds me of a teenager chewing the neck drawstring of a hoodie. The best fidelity probably comes from the adapters that plug into the antenna port on the back of the radio, but those require pulling the radio out of the dash to install. Another option is an FM transmitter that connects to your phone via an aux cable and then sends the music to your radio on an unused FM channel. These require zero modification to the radio, and work well enough to be useful, although on long drives you may need to fiddle with the tuner when formerly-unused channels start playing Faron Young and Red Sovine.

A related problem in vintage cars is the shortage of cigarette lighter plugs and the tangle of power cables for all the ancillary devices we now consider necessary. There’s one for your phone, another for the radar detector, and in my case another for the FM transmitter, the iPod, and perhaps the Cambridge Soundworks portable stereo. It used to be that you’d need yet another lighter socket for the GPS, but fortunately GPS units have been largely replaced by phones. (As recently as two years ago, I still brought the GPS on road trips in case I was in a rural area without cell reception, but with phones now having GPS chips in them, I’ve cut this cord.)

An additional related issue is that I like to use a cigarette lighter voltmeter to monitor the alternator’s output in real time, since failure of the alternator to adequately charge the battery is one the main reasons that a vintage car could die on a long trip.

Although I can itemize the needs, the tangle of power cords shown in the picture above is ridiculous. Years back, I bought one of those three-into-one cigarette lighter plug adapters that looks like cat-o-nine tails you’d use to flog an errant sailor on an 18th century whaling ship, and even that wasn’t enough. I eventually bought a box with three cigarette lighter plugs and also had two USB connectors that the phone cables could be plugged into.

I suspect that I am not alone in the vintage car tangled power cord jungle. While I am a practical guy, to me, a lot of the joy of driving a 1970s-era German car is the functional sparseness of the interior, and while it’s understandable how you take that sparse perfection and junk it up because you want the modern conveniences of cellular coverage, infinite music selection, navigation, and traffic and law enforcement avoidance, the tangle began to bug me.

For this trip to Asheville in the 635CSi, I assumed that I’d just use the FM transmitter I have in our Winnebago Rialta (which has the same problem of an old cassette unit with no aux port), but when I tried it, I found that it had died. This gave me the opportunity to look for what’s new.

Of course, the problem is that when you search for “aux FM transmitter” on Amazon, you get hundreds of hits. But once I waded through them, I did find some things I wasn’t aware of.

First, on the simple issue of power distribution, I found something I really like. Cigarette lighter expansion adapters aren’t rocket science, but this one from Tesla (not the same as the car company) is very appealing. It has three lighter sockets and four USB plugs, one of which is fast-charging (2.5 amps at 5V). It will support up to 120 watts of power. It’s simple, black, doesn’t have any blue neon-colored lights in it, and substantial enough that it doesn’t feel like you’re going to dent it with a coffee cup. It has an on-off switch so you can kill power to all of the devices without unplugging it. And, my favorite, it has an always-displaying voltmeter integrated right into the plug, eliminating the need for a plug-in voltmeter. This assuages my paranoia that I’m driving with a dead alternator and will only find out when there’s no longer enough voltage to run the fuel pump and fire the spark plugs. With its black simplicity, the box looks very much at home in my 635CSi.

This cigarette lighter adapter gives you three plugs, four USB ports, an on/off switch, and a voltmeter. Bliss.
This cigarette lighter adapter gives you three plugs, four USB ports, an on/off switch, and a voltmeter. Bliss. Rob Siegel

On the FM transmitter front, with everything going Bluetooth these days, it’s difficult to find something that’s not Bluetooth-enabled. Keep in mind that anything FM and/or Bluetooth needs power, so any transmitter will either need to be plugged into the cigarette lighter or will have an internal battery that needs to be recharged. If you have a free cigarette lighter port, you can buy one of a hundred Bluetooth adapters that plug directly into the lighter socket. Many of these units have a screen that’s supported by a flexible stalk and which displays the Bluetooth information you’d see in a new car’s integrated screen. The FM/aux thing is usually just a small fraction of what they do.

For my 635CSi, I didn’t want something that looked so starship Enterprise, so I concentrated on the subset of FM-aux lighter plug-ins that were smaller. To my delight, I found that some of these offer multiple USB plug-in ports to power phones and other devices, and, if you search, you can find some such as this one that also show the voltage present on the lighter port. You have to look at the descriptions carefully, as some models will only show the voltage when you plug them into the lighter socket. Also, because so many of these devices are Bluetooth-enabled, sometimes their use of the aux port is so the device can connect to the phone, not so the phone can send audio to the device (I know, it’s weird). So if you are using it in the old-school way of connecting a phone or iPod so you can get music into the radio, you need to make sure the device advertises “aux input/output.”

This and other cigarette lighter adapters offer Bluetooth connectivity, an aux port for connection to your phone/iPod, an FM transmitter to get the music into an old radio, and two USB power ports and a voltmeter.
This and other cigarette lighter adapters offer Bluetooth connectivity, an aux port for connection to your phone/iPod, an FM transmitter to get the music into an old radio, and two USB power ports and a voltmeter. Rob Siegel

Because both the new power distribution box and the new FM-aux adapter I bought had voltmeters in them, I didn’t know which one I’d keep (hey, Amazon Prime—easy returns), so I also bought this tiny FM transmitter, about the size of two postage stamps, which plugs directly into the iPod’s aux port. The upside is that, when using it, there’s not an aux cable stretched between the iPod and a transmitter that’s plugged into the lighter adapter. The downside is that the little transmitter has to get power from somewhere, so it has a little battery which needs to be recharged. I’ve found that if I fully charge the batteries in both the iPod and the transmitter, they can both run in the car all day. This is nice in terms of being able to pick the thing up and switch songs without yanking out cables (one of the reasons, I suppose, why folks like Bluetooth). I wound up keeping the tiny transmitter and returning the one that plugs into the cigarette lighter. And, yes, I could also pair it with my phone via Bluetooth, but I probably won’t.

This tiny Bluetooth FM/aux adapter eliminates the aux cable between the phone/iPod and the FM transmitter, but its internal battery needs to be recharged
This tiny Bluetooth FM/aux adapter eliminates the aux cable between the phone/iPod and the FM transmitter, but its internal battery needs to be recharged. Rob Siegel

So, with the ditching of the GPS, the new cigarette lighter box and its integrated voltmeter, the little FM transmitter that plugs into the iPod/phone, and a commitment to charge the iPod and the transmitter overnight, the number of power connections has dropped to two—the cigarette lighter adapter for the radar detector, and the USB cable to keep the phone running Waze fully charged. Much better. Much cleaner. And I have gobs of extra power ports in case I need to, I don’t know, make coffee or inflate a tire while I’m driving.

Now I just need to order those cables in black to match the 635CSi’s dark German sparseness.

***

Rob Siegel has been writing the column The Hack Mechanic™ for BMW CCA Roundel magazine for 30 years. His new book, Just Needs a Recharge: The Hack MechanicGuide to Vintage Air Conditioning, is now available on Amazon. You can order a personally inscribed copy here.

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