Wiring headphones to knock sensor?

tianporn · Post by **tianporn** » Fri Sep 16, 2005 7:56 pm

Hey, during a Hondata seminar recently here in New Zealand, Doug Macmillan said it was possible to hook up a headphone to the knock sensor (since it is a small microphone) and you will be able to detect knock while tuning.
How would this be done? I assume you would need some small amplifier of some type. Anyone done this or have any writeups they can share?

My car is a JDM EG9 Civic with P30 so there is a factory knock sensor on my motor.

Thanks!

Post by **Hondata** » Tue Oct 25, 2005 9:23 am

Use a small amplifier connected to the knock sensor input. You can modify cheap PC speakers to do this.

marlborocars · Post by **marlborocars** » Tue Oct 25, 2005 10:18 am

Or and amp for hearing impare $15 at Radio Shack.

Razathorn · Post by **Razathorn** » Thu Dec 08, 2005 12:13 am

Whoa! What does it sound like? Just like loud pinging?

Post by **Hondata** » Thu Dec 08, 2005 8:21 am

There is a lot of valvetrain noise, but you can hear knock. It sounds more like a sharp 'tick' sound.

Razathorn · Post by **Razathorn** » Thu Dec 08, 2005 10:33 am

Hondata wrote:There is a lot of valvetrain noise, but you can hear knock. It sounds more like a sharp 'tick' sound.

It would be really cool if we had some sound clips for download of what knock sounds like in various conditions for those who don't know exactly what it sounds like.

I know quite well what it sounds like if I can hear it over my exhaust in my car -- I helped a friend with crower cams in his k20a2 who thought he had valve train noise and I instantly identified it as real knock, no question. The sound is very unique in the passenger compartment with the windows up. Does it sound the same on the speaker? I could see it being described as a tick.

I've always struggled to use an onomatopoeia to describe the sound knock made. When I heard it for the first time I thought 'damn, it just really doesn't sound like a 'tick' or 'marbles in a can', but I can see how those could be the closest things to compare. Personally I think it sounds more like somone dropping chainmail on a hard surface, or somone taking a small maraca and shaking it once in one direction.

The idea of having an ear plug that would allow you to hear knock in real time without having to keep an eye on the CEL for flashing is a really cool concept. Hearing it at low rpms is not hard, high rpm is another story -- this could be a great tool.

Wayne