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Let's Talk Car Radios...

At long last, Crutchfield has started carrying a retrofit kit to allow aftermarket sound systems to "fit" the Honda Fit (which, incidentally is a great 38mpg car for a traveling contract engineer). The factory radio has the WORST sounding AM section I've heard. So it's now possible to look at an upgrade. I'm looking for input from an engineer's perspective on some good...no, great car radios. I'm looking for one with great FM sensitivity/selectivity and importantly, good sounding AM with at least 6-7khz response. A CD player is a must wih HD and Sirius/XM "ready" status preferred. As one who isn't a fan of HD, just having the option to add an integrated adapter in the future would be fine. Anyone have a current model that meets these desires that you're happy with?
 
I'd chase down one of the decent aftermarket FMs which takes either Sirius or HD via adaptor. Kenwood and several others have good product. Then, I'd find me one of the McKay-Dymek tuners we used to use for studio monitors for AM stations, and get a cigarette lighter 110V adaptor for it and feed it into the AUX jacks on the tuner/cd/hd. Everyone's current AM product I've heard sounds like hammered roadapples. I looked at the Honda Fit and found it totally whelming in pretty much every regard. Each to his own.
 
I would pick based on the best FM tuner spec that came with an audio input jack.
Any audio could feed in, without worries of becoming obsolete.
NONE of the current AM radios are even adequate.
If AM is important, find one you like from the 70's, and modify it to pick up the expanded band.
Feed the audio from that detector to the input jack of the aftermarket radio.
If there's a new aftermarket car radio out there with a real tuned RF amplifier for the AM, I'm unaware of it.
My favorite car radios are old Bendix, Motorola (60's 70's), and Blaupunkt (1982).
They were some of the best compromises ever on sensitivity/selectivity/audio response.

But no current models I've tested would satisfy me for AM.
 
Tom Wells said:
I would pick based on the best FM tuner spec that came with an audio input jack.
Any audio could feed in, without worries of becoming obsolete.
NONE of the current AM radios are even adequate.
If AM is important, find one you like from the 70's, and modify it to pick up the expanded band.
Feed the audio from that detector to the input jack of the aftermarket radio.
If there's a new aftermarket car radio out there with a real tuned RF amplifier for the AM, I'm unaware of it.
My favorite car radios are old Bendix, Motorola (60's 70's), and Blaupunkt (1982).
They were some of the best compromises ever on sensitivity/selectivity/audio response.

But no current models I've tested would satisfy me for AM.
I've heard AM radios in recent minivans that sound decent and my wife's Toyota Solara has an AM radio so good that with the treble at +6, the IBOC hiss is audible. I know I'll never find anything truly great on AM, but if I can just find one as good as the '99 Solara's factory radio, I'd be delighted. Same goes for the radio in a 99 Ford Ranger...the HD hiss is there & it sounds decent for AM. I hope that everything on the market now doesn't have 3khz AM audio...did they stop making 6khz AM radios in the 90's?
 
Some Ford and Chrysler radios did seem to have decent high-end response up to 2003 or 2004 model year.
I remember actually being able to hear some of the 10 khz station beats on a Ford radio.
On these, the treble control does have an effect.
Lately though, all the rental cars I've driven are "lopped off".

As an contract engineer, don't you long for an analog continuous tuning AM radio?
I feel positively claustrophobic using a fixed step-tuning AM radio with 3 khz cutoff.
 
Tom Wells said:
As an contract engineer, don't you long for an analog continuous tuning AM radio?
I feel positively claustrophobic using a fixed step-tuning AM radio with 3 khz cutoff.
Sure do Tom...At least then I could detune by 1-2khz and hear a few more highs. This car has been practical for it's amazing amount of cargo hauling capacity, but I've been frustrated on a daily basis by the horrific AM freq response. Finding the features I want for FM is proving to be more of a chore that I expected. Some of them have no preset buttons! That and bad AM audio would drive me to buy an iPod...
 
I've got a '96 Grand Caravan with the Infinity upgrade. The AM isn't completely awful on it. If you could find a late 60s Delco upline (Oldsmobile, Buick, or Cadillac) radio, they had excellent AM performance. It would be a job to fit one in a modern dashboard, but might be worth it for the results if you do a lot of AM work on different stations.
 
littlejohn said:
I've got a '96 Grand Caravan with the Infinity upgrade. The AM isn't completely awful on it. If you could find a late 60s Delco upline (Oldsmobile, Buick, or Cadillac) radio, they had excellent AM performance. It would be a job to fit one in a modern dashboard, but might be worth it for the results if you do a lot of AM work on different stations.

I sure do miss the Cadillac radio that I "retrofitted" into the dash of my '76 Pinto, the junker I drove back when I was a poor college kid. It had Delco's old motorized "signal seeker" -- anyone else remember those? As you say, the AM section sounded quite sweet and the FM wasn't bad either for a late '60s radio. Sensitivity improved greatly after I went in and tweaked the trimmers on the tuning capacitor.

This radio had the classic Germanium Class A output stage, two big stud-mounted Delco transistors on an external heatsink; I had to remove that from the radio chassis to make it fit in the Pinto's radio hole and decided to make up a short extender cable and hang it under the glove compartment. Helped keep the car warm during long winters in upstate New York.
 
I bought a junker Delco signal seeking radio that was made for a '67 Lincoln Continental, which we had for few years in the 90's.
It needed a better on the switch for the return-solenoid circuit. The original switch was way too light-duty.
I took apart an industrial relay, and fitted the contacts to the moving mechanism. Much stronger than the original.
The only other problem was that the seeking movement was a bit fast, so that when the AVC voltage rises stopping the
"escapement fan", the signal was not on center, but a bit past center. I still need to put some more viscous grease in the
escapement fan hub to slow it down. When we sold the car, I took that radio out, and put back in the AM/8-track.
The new owner was excited about the 8-track!

This radio does AM the right way. Tuned RF input, very effective AVC, and inductive slug tuning.
Most car radios of this vintage used an IF frequency of 262.5 khz, as it is easier to design an RF amp with sharp-cutoff response
at this freq instead of 455 khz. This permitted more of a broad, flat-topped response curve that rolled off high frequency audio less,
while still giving a sharp cutoff for good selectivity. The resulting "image" frequency is 525 khz, which is less problematic than the 910 khz images from 455 khz IFs, since the image response does not fall on another even 10khz step.
However, this lower frequency needs the tuned RF section to keep the "image" response down.
I don't know how easily one of these can be shifted to permit reception up to 1710 Khz.
My old Bendix car radios were pretty easily to re-trim on he upper end of the AM, but my Motorola could only be tweaked up to 1650.
Those big germanium transistors sure know how to suck down a car battery, but sound really good.
 
Take a look at the signal seeker - those old 'Wonder Bar' radios originally had a bit of a spring on the shaft which the motor drove, so that when it stopped, the spring would back up just a bit. When everything was clean and oiled, it was just enough to center the AGC.

And, having worked for an AM on 910KHz, lenmme tell you, we loved auto radios with a 262 IF!
 
hipporadio said:
BobOnTheJob said:
...the main things I want are great sensitivity, great selectivity and a good AM section that doesn't sound like there's a pillow over the speaker. Suggestions?

I went thru this ritual a year ago when the factory radio/CD in my GMC Jimmy died. Since it’s a second vehicle, I didn’t want most of the bells ‘n whistles that excite mobile-audio buyers – just a GOOD under-$200 radio with CD playback. Since I listen more to AM these days, I tried to find a model that performed well. My search was less-than-gratifying... Image the look of a “sales-type” in the car-audio department when you ask about AM :eek: ::)

Frankly, radio [in general] is far from the minds of the CE folks these days - which may-well indicate an absence in the minds of the consumer also. They seem to be more interested in iPod connectivity, multi-format CD playback, animated displays, and sat-radio. I finally "settled" on Pioneer’s $175 model P4800MP. It offered all the aforementioned features [minus the “cartoon display”]. The FM performance is very good... AM sensitivity was better than the current Alpine, JVC, and Sony models I have heard in other vehicles. AM sound quality is "OK" – but I doubt there is a wealth of audio much-beyond about 4.5-5k that manages to make its way through. Still, a well-engineered AM playing popular music can be enjoyed with "reasonable expectations" and talk stations sound good.

The current replacement is the D4900. Both use the “SuperTuner III-D” [featured across the entire Pioneer product line], so I imagine the performance is identical on all models.

BobOnTheJob said:
I've heard AM radios in recent minivans that sound decent...

My parents recently purchased a 2007 Chrysler mini-van. It has the “intermediate” audio package; and the radio section performs very well. Comparing it with the Pioneer P4800 [above]: the FM section [which offers RDS] is a bit less-sensitive – AM sensitivity is about-equal, but audio bandwidth is better. They live in a community where Bob engineers a fine little AM station that features a classic hits format [YES - music on AM], and the factory radio provides very-pleasing audio quality. I have not heard this station on the Pioneer unit in my vehicle, but often listen to Oldies on a similar [but less-sophisticated] local suburban AM and sense that the aftermarket radio pales noticeably in audio quality and fidelity.
 
Well...since I started this thread & made a decision, I thought I'd share my results. The receiver with the least negatives was the Alpine 9885 with the HD tuner. I figured if I was gonna criticize HD, I needed to experience it first hand. Here's my overall view of the selected unit...

* FM sensitivity & selectivity are far superior to the factory Honda Fit radio.

* AM sensitivity is at least equal if not better than the factory unit. WSM at 240 miles in the day is possible.

* AM frequency response is a lot better than the factory radio....and this was a primary reason to upgrade as the factory AM was arguably the worst sounding AM ever. Keep in mind that the HD tuner is actually demodulating the analog AM so it's uncertain if the 9885's AM section sounds like this or not. I wouldn't say that it could be mistaken for FM, but music on AM is enjoyable to listen to again.

Now to the HD section...While I hate the interference that HD causes to adjacent channels, let me set that aside & offer my assessment of HD reception using this radio in the Indianapolis to Cincinnati area...

* The AM HD doesn't sound like FM, but it sounds better than AM. It sounds like an excellent sounding dial up stream or perhaps a little better. The AM's I've heard are underprocessed to the point that it detracts from the enjoyment. When the radio switches from analog to HD, the volume and density drops & the difference has varying degrees of irritation. All stations except one that I heard on AM had the delay aligned properly...but the one that had it totally screwed up was 700 WLW. That one was several seconds out of alignment & it made them unlistenable on this radio about 40 miles out. One substantial drawback of this radio is that (unless I haven't figured it out) it doesn't appear to allow the HD to be disabled. And in cases where the signal is iffy, it will switch back & forth enough to aggravate you.

* FM HD sound...My ears are in pretty fair shape...I've lost track of the number of stations I've set processing for. So I should be a good judge of this. When the radio switches from FM analog to FM HD, the sound has just a touch of that "streaming' sound to it. I only notice it when it switches...without an A/B, it's so minimal that it's hard to detect. But it **IS** there. The time aligment on all FM's I heard was perfect. The sound quality is not superior to analog except that the pre-emphasis/de-emphasis issue is absent. Our friends at Omnia & Orban have pretty well made that an analog non-issue anyway. Unlike AM, the FM HD is reasonably processed. In my view, if there is a "benefit" to this, it's the multicast channels. WFMS 95.5 in Indy is running non-stop oldies on their HD-2. No commercials, jingles, ID's...nothing but a well crossfaded jukebox. Traveling through indy, I did enjoy that.

* HD coverage area...On AM it varies by station...some stations that you don't expect to get in HD do well as far out as 75 miles. Others that you'd almost bet the farm on only lock in sporadically. The FM is more predictable. We drove for an hour while listening to WFMS HD2 and it only flaked out when we drove past 50KW WGNR 97.9's transmitter at 28 miles. The Class B HD's (which are really class A's or less when you consider their TPO vs the analog) are solid to the 70db contour & about 70% at the 60db circle. The terrian has a pretty strong effect between those two contours. There is virtually no FM HD reception beyond the 60db mark.

It's been tough to not editorialize on my feelings about HD. I've already nailed that topic to the wall countless times. I tried to present an evaluation of what appears to be a worthy contender for a contract engineer's auto receiver. Hopefully I've succeeded at that...
 
Only one comment -

If you can find someone who is allocating the entire HD stream to the main channel, you'll lose the coding effects. Slice it up, though, and they will begin tio appear.
 
I rented a Dodge Stratus a couple of years ago in Milwaukee. It had a teriffic AM stereo radio that made WOKY sound better than most of the FM's!
 
Just wondering if anyone's ever heard of this happening:

One night about 2 years ago, we had temperatures drop below 10 degrees. The next morning all the calibrations were off on my radio. AM was only off one position, but it was more like 8 positions on FM. (Our station on 1060 came in on 1050 and 104.5 came in on 103.7). After you drive awhile, then turn the engine off and restart it, the radio would be OK.

Since then, it would do that at higher & higher temperatures. At first it seemed to do it only in the winter below 20 degrees, then 40 degrees, etc. Now it does it all the time regardless of the temperature. And turning the engine off and restarting it doesn't work anymore. On FM, nothing comes in lower than 95 or 96 on the dial. The dealer told me it isn't fixable and I'll have to replace the entire unit. (The 6-disc CD player works fine).

It's a 2003 Hyundai Santa Fe.
 
Ahh, the marvels of technology and new innovative ways of breaking......

Sounds like a step-voltage output is wacky or the varactor tuning diode for the local ocscillator.

It could possibly be poor grounding to the frame of the vehicle.

Where is it already this cold? Ouch!

We inherited a 2004 Santa Fe. Now I'll always be waiting for this to happen.
Does your have the antenna in the back window? Ours does, and it's the awful-est deaf AM antenna I've seen.
I have one to poke into the front fender but haven't done it yet.
 
Sgeirk said:
Is it one of those Monsoon radios?

Yes, a Monsoon.

Tom Wells said:
It could possibly be poor grounding to the frame of the vehicle.
We inherited a 2004 Santa Fe. Now I'll always be waiting for this to happen.
Does your have the antenna in the back window? Ours does, and it's the awful-est deaf AM antenna I've seen.

My last two vehicles were GM and they both had grounding problems, too. Everytime you hit the gas pedal, you'd get a steady annoying hum on AM.

Yes, the antenna's in the rear quarter window. Well, if I had to choose between that annoying hum and getting my AM stations one dial position over, I guess I can live with the dial problem.
 
one word

Mopar

I'm using mopar plain-jane AM-FM's for off-air monitoring of our AM's as well as retro-retro-fitting both my 92 Voyager and my wife's 96 Grand Caravan with junk-yard take-outs (took out JVC's because the AM portion sucked big time)

with a mopar unit I can sit under the towers at 5 kW on 1070 and kisten to KMOX in St. Louis on 1120, 70 miles away; the JVC's would totally block all AM when I got within a mile of the array

when Chrysler starts offering a factory HD radio, I will go find one of those and test it out

but for now, what I have works and works well
 
I agree...

Mopar Rules!!!

I have a 2004 Dodge Ram 1500 and A 2006 Chrysler Town and Country, both of them are equipped with the factory RAZ AM/FM/CD/Cassette radio. These radios have the best sounding AM of ANY car radios I have listened to in many years. The AM sound rivals many FM's. I can drive right up to the local 50 KW tower on 660 here and still tune in any other frequency without any noticeable signal degradation.

Speaking of antennas, does anybody remember GM's famous dipole antenna that was embedded into the windshield of of most of their cars made in the 70's? The antenna worked fine on FM but was terrible on AM, as its vertical height was only about 18-19 inches. If you were listening to AM and had to run the windshield wipers, the signal would come and go with every swipe of the wipers.
 
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