HELP: Canon 135mm F/2.0L Ultrasonic sound vs Other Ultrasonic sound

[ELL10TTx]

Hi,

I just bought a used Canon 135mm F/2.0L and the sound coming from the ultrasonic auto focus is louder and a higher pitch then both my 50mm F/1.4 and 28mm F/1.8 ultrasonic auto focuses.  Is this louder sound normal?  Or is it supposed to sound like my other 2 lenses?

It's also louder than my 28-70mm F/2.8L and 70-200mm F/2.8L IS 1.

Thank You for your help.

[IIIHobbs]

I do not have either of the 2 lenses you are comparing to the 135, but I do have a 135L and it is nearly silent unless I have a very difficult focusing situation (bad lighting or difficult background). My 24L and 50L are also nearly silent.

It may be the size of the glass in the 135L compared with the 50 and 24 you have. The focusing system is moving a lot more glass in the 135 than the others.

The noisiest lens I ever had was the 300mm f4L; often sounded like it was broken inside.

[Axilrod]

That's definitely not normal, 135L is pretty quiet and the only noises I just heard on mine were subtle clunks (for lack of a better term), but definitely not high pitched at all.  Should be much quieter than the other lenses you mentioned.