Today I build myself a *knock headphone*.The design is so simple ,it took me 30 minutes total
here is what you need :
ear defenders
1 foot of copper pipe 3/8"
about 10 feet of hose (fuel hose will do )
a 3/8 " T piece
2 3/8" -1/8 npt barb fittings
Drill the defenders in the lower spot and tap the holes to 1/8 ntp
fit the barb and slide the hose on them, the connect both hoses to the T-piece.
Flatten the copper pipe and drill a hole in it then bolt it to the head (or block)
Slip the hose over the pipe and over the T piece aswell
done:
Does it work? Yes it does
You can clearly hear any noise coming out the engine
You will clearly hear the motor Knocking .The sound is very distinctive from other noises!
So before you go out and buy the Turbos XS tuner pro or the HK$ knock amp try this .It cost me about $40
Lawrence
here is what you need :

ear defenders
1 foot of copper pipe 3/8"
about 10 feet of hose (fuel hose will do )
a 3/8 " T piece
2 3/8" -1/8 npt barb fittings
Drill the defenders in the lower spot and tap the holes to 1/8 ntp
fit the barb and slide the hose on them, the connect both hoses to the T-piece.

Flatten the copper pipe and drill a hole in it then bolt it to the head (or block)
Slip the hose over the pipe and over the T piece aswell
done:


Does it work? Yes it does
You can clearly hear any noise coming out the engine
You will clearly hear the motor Knocking .The sound is very distinctive from other noises!
So before you go out and buy the Turbos XS tuner pro or the HK$ knock amp try this .It cost me about $40
Lawrence