Audio Question

[ksbeta]

I've searched around and read the different forums regarding Radios, speakers, etc. I still have some questions though, mostly probably stemming from not having done enough research prior to ordering parts.

I have a 2/'70 build date 240z. It came without the radio. I pulled the panel off in the rear, and the original speaker was there, albeit destroyed, and the power antenna was missing as well.

I shied away from spending the big bucks on a Series-1 radio, and instead opted for one pulled (I believe) from a ’73. I also found a power antenna (locally) that worked, but upon later research appears to be from a 280z. Finally, I’ve ordered a set of Pioneer TS-G1343R 5.25” speakers, which were recommended (low watt, shallow magnet).

I attempted to install the radio, and was dismayed to find out that the wiring harnesses changed. The radio has the same male connector required for the power antenna, but the straight-three format (blurry photo of the rear of the radio) for what I believe is the speaker connection (?). It also has a red wire I assume is power, and the FM antenna connection.

The harness on the dash (photo is clearer) has a connector for the power antenna. But, what I assume is the connection for the radio is different; 2 vertical slots and 1 horizontal slot (also shown).

Question #1) From what I’ve read, the radio/wiring harness changed. To use this radio, I would (shudder) have to hack something together? Or create some ridiculous middle harness?

Question #2) I’ve also read that it’s a bad idea to wire a second speaker up (in parallel or otherwise) to the mono-setup. Might blow the radio. Is this true? Even if you pulled it off, would you have true “stereo” sound or simply “mono” coming from 2 speakers?

Question #3) All the links I’ve found to vendors who sell the mirrored speaker bracket are dead. Anyone know where to get this; or a simple/cheap work around?

Thanks in advance,

Bill

[Walter Moore]

1) Yes. You will have to modify the wiring somewhat to install the later radio. There are not many wires involved, but if that frightens you I suggest consulting a professional.

2) Probably. The radio's final power amplifier is designed to drive a certain load. Generally this would consist of a single speaker with an impedance of 8 Ohms. If you wire two 8 Ohm speakers in parallel the effective impedance drops to 4 Ohms, which will draw twice the current at any given volume setting. This could over heat the power transistors in the amplifier, causing them to burn out. And yes, the best that you could hope for is two speakers producing the same exact sounds. As you put it "mono" not stereo.

3) I have no idea where to obtain speaker brackets for the right rear of the early cars. That side of the car is very cramped because the fuel filler neck and the expansion tank are hidden under that panel. There really isn't any room for a speaker there anyway.

[Arne]

3) I have no idea where to obtain speaker brackets for the right rear of the early cars. That side of the car is very cramped because the fuel filler neck and the expansion tank are hidden under that panel. There really isn't any room for a speaker there anyway.

Actually, a speaker fits there just fine. I have a Kenwood there in my car. I built my own right side bracket by re-bending a spare left side bracket. Others have made rights side units from ABS sheet plastic.

[FastWoman]

That's actually a 4 ohm speaker. You could wire two in series for a combined impedance of 8 ohms. Some of the older car radios might have an output impedance of 8 ohms, in which case this would work fine. If the output is 4 ohms, then the total sound output when driving an 8 ohm combination would be less than it would be when driving a single 4 ohm speaker. It's important to match impedances.

And no, two speakers do not make a stereo or create a stereo effect. You have to have two separate audio channels driving those two speakers.

That said, you might address both issues by sending the output of the radio into a power amp with a reverb circuit. It's cheesy, IMO, and you would be hard-pressed to find such an amp these days, but it would create a stereo effect AND drive both of your speakers with proper impedance matching. You could solve the latter problem (without stereo effect) with any power amplifier. A power amp mounts well behind either of the seats, perhaps under a seat, and perhaps even inside one of the tool boxes behind the seats.