TRRS headphone connector as amp on/of switch?

[with_a_you]

Hello,

So I'm a first-time user here and I own a 1963 Nova with pretty much original everything INCLUDING the fact that the original owner ordered it WITHOUT a radio (so there is a rare factory-installed delete plate where the radio should be).

I'm in the process of installing an amp either under the seat or in the trunk and two 6x9's in the the rear deck (saving the original rear deck so I can return the car to stock if ever needed) and I'd like to simply run RCA's from the amp to a headphone jack for my iPhone for music. This seemed pretty straight-forward and simple.

Then I got to thinking.

The new iPhones/iPods have TRRS jacks/cables (and not just standard headphone TRS jacks) and have an additional ring on the jack end and an additional wire inside the cable so they could add the volume and play/pause controls to the headphone cable. MY QUESTION IS can this additional ring be used to complete a circuit (or cut a circuit) and flipping a relay to turn the amp on (so the amp turns on and off when the iPhone is plugged in)?

It seems simple in my head, but I've never seen it done (but I also don't deal too much in car audio).

Anyone seen this before?

Thanks in advance!

- Brad

Oh, PS... If anyone has any amp/6x9 suggestions that would be good keeping in mind I'd have no EQ controls in the car that would be also great!

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[keep_hope_alive Premium Member]

no, you cannot use the internal circuitry for an amp turn-on, the load on the ipod would destroy that circuit. bad idea. you'll need to rig a switch for manual turn on. remember amp on after you connect the ipod, amp of before you disconnect the ipod.

many cars in that era had one speaker in the center dash and one in the center rear deck. yours didn't since it didn't have a radio option?

We used Type-R 6x9's for affordability. Hertz High Energy 6x9's are some of the best sounding i've heard.

here is an install i did in a 1960 Chevy Bel Air for inspiration

rear Type-R 6x9

existing wiring was a bit disorganized. i added two Bussman ATO fuse blocks, one battery and one ignition (fed from battery through a relay). the sound system and electronics, gauges, etc. are completely separate from factory fuse box. i want to clean this up.

we did a retro sound in-dash, comes with vehicle matching trim plate

comes in chrome or black and the knobs are infinitely adjustable. has aux input and USB input, built-in amp and RCA outputs.

I also put a cruse control system in this car since he drives it to shows.

 

[with_a_you]

Thanks for the photos and advice! Definitely a nice setup on that Bel Air.

I know there is some level of voltage in the sleeve (4th ring) of the TRRS jack that the iPod/iPhone interrupts with different resisters for the different buttons on the headphone cable (play/pause, track forward, track reverse). But, my BIG wonder is can you separate out that one wire and send it to a circuit, and when it senses that voltage change (that would happen when the cable is plugged into an iPod/iPhone), it activates a relay to turn on the amp.

I definitely am comfortable wiring a switch to turn the amp off and on from under the dash or in the glove box etc, but since I went down this road of owning an impractical car I also thought to myself, "Hey, why do any of this the easy way?" and think it'd be cool if the amp was controlled by the presence of my iPhone and not just the car being on or off.

Thanks again and thanks for the speaker recommendation!

 

[keep_hope_alive Premium Member]

Yes, you could do what your thinking... If you know what load the iPod wants to see. A bjt transistor or 555 timer could be used. The base of the bjt requires very little current. A 555 timer could sense the voltage or audio signal.

Or you could buy an amp with an auto turn-on.

 

[with_a_you]

Keep Hope Alive,

Thanks again. Your advice actually lead me to finding this:

Amazon.com: PAC TR-4 Low Voltage Remote Turn-On Trigger: Automotive and other similar products and I think I got my answer (just never exactly knew what I was looking for).

 

[keep_hope_alive Premium Member]

Good luck