M7 horn

What type of horns are used on the M7s? They seem to be much louder then those on the other Mus as well as the diesels. Are they of a different type or are they louder because the air has not been adjusted on them yet? I can hear a M7 horn from my house half a mile away. I can bearly hear a M1/3 horn more then a few hundred feet away.

On Diesels and M1/M3 the horn has two positions, Half and Full. on M7's there is only a full blast option.

I thought I remembered someone saying a while back that the LIRR M-7's horns were going to have the half and full blast capability. They supposedly wanted to avoid the same kind of debacle they had with the loud DE/DM-30 horns when they came into service, which were later changed due to the huge public outcry.

Anyone know where to buy actual air horns? I'd like to acquire either a 3 or 5 chime air horn for my trunk hooked to a compressor that I can put under my seat. I've seen it done before, I just don't know where to start looking for the air horn!

The horns on the M-7's are much like everything else on the RR in being powered by air. The M-7 essentially have a sort of a handle which the engineer simply pulls it down. The intesity of the blast is all based on how far down the engineer pulls the handle down. I have blasted the horn on a number of occassions and have been able to give it a short light "toot" without blowing anyone's eardrums.

When I lasted looked under the front of the M-7, I noticed that there was a two-chime horn. They're actually quite visible on the left hand side of the front of the M-7's. I actually have worked on some that seem to have had a more melodic chime to the horn sounds, almost sounding like a 3-chime horn. It can quite possibly be a 3 chime horn with a smaller horn hidden behind the larger two horns that are visible. But like I said, I'm not 100% sure. One thing I do know is that neither the M-7's nor the M-1/ M-3's have a single horn or "honker". When I used to work for the warehouse department, I remember running into a rather large box that contained M-1/ M-3 horns. They were essentially two horns attatched to the same base. My guess on the sounds of the M-7's is that the horns are either a completely different size or type from the M-1/ M-3's.

I decided to do some spelunking around under the cars in the shop to see what was there. You will be surprised at the results.

M-1 has only one horn trumpet--- a Leslie Supertyfon #44

M-3 and M-7 have the exact same setup---2 Leslie Supertyfon trumpets; one being a #31, and the other one a #44. (The #31 is the larger horn) They may sound different because of possibly different diaphragms and/or amount of air passing thru.

Parts list for M-7 horn array:

i've heard the horns it sounds as loud as a boat horn