Making of Rabbit Ears Audio Metal Machines SFX Library

Michael Raphael is a professional sound recordist and designer. He is also the creative force behind the boutique sound effect studio Rabbit Ears Audio and the long-running field recording blog Fieldsepulchra.

I have to admit I have a bit of a fondness for trains. One of my earliest SFX recording gigs was a job that had me recording at several train and trolley museums.  I was hired to record several turn of the century street car trolleys and an old steam train repair shop. During those sessions a  metal chuck flew off a lathe and struck me in the foot.  I had to finish the session with a swollen foot, but I managed to make it through the day. Despite the injury, I’ve been enamored with the sounds ever since.

Because of that experience, I’ve kept track of shops that worked with old machinery. There are just a few places in the US that restore old steam trains and work with such machinery.  For this recent recording, I went on a few site visits to different locations. I finally settled on the shop with the 1910 Wheel Lathe.  It is just one of two that is still fully operational in the country.

After hearing it, I knew I had to record it.  The wheel banged and rattled, while the gears in the back just clinked and grinded along so wonderfully.

The rest of the shop was filled with character as well.  Here’s the complete list.

  • Wheel Lathe
  • Metal Planer
  • McCabe Metal Flanger
  • Metal Shaper
  • Summit Engine Lathe
  • Summit Engine Rapid Traverse
  • Hendy Engine Lathe
  • Vertical Turret Lathe
  • Bridgeport Milling Machine
  • Large Air Needle Scaler
  • Small Air Needle Scaler

All of the machines pre-date 1950 and except for the Needle Scalers, they were all heavy duty machines that require a fair bit of setup before we could start recording them.  This brings me to the challenges.  I knew that I was only going to be able to hire the shop and machinist for 7 hours and we weren’t going to be able to get started until work was done for the day at 4:00 PM.

After learning all of this, I needed to figure out how to get the most out of the session.  It was at that same time that I was also preparing for a century bike ride with my audio engineer cycling buddy, Rob Byers.  I knew having an extra set of experienced hands would get us through the day more efficiently.  I sweet talked Rob into coming out early for the session and boy was I glad that I did.

When Rob works he is as serious as a heart attack.  We managed to record each machine from multiple perspectives efficiently and it is always good to have a second brain on the job that can make constructive creative decisions.

Rob’s the guy with the MKH 60 (left) and coincidentally he is the guy jumping in the pool in my hydrophonic library.

Before we even started recording that day the day we spent about an hour getting to know Eric our Machinist.  We were going to be working with Eric for 7 hours in a dark shop and getting off on the right foot was extremely important.  I was concerned that we were going to be working with a surly guy who was just out to make some extra overtime, but instead, we managed to work with someone incredibly enthusiastic.  Eric helped us understand every machine, how they functioned, and what parts of the machines made the most interesting sounds.  Our session would have been far less successful if Eric wasn’t an excited participant.

With a great machinist leading the way and colleague in tow, we methodically made our way through all of the machines.  Eric always tried to get the most out of each machine, and because there were two of us we were able to record from two different perspectives on most units.  One of the nicer results from our different setups was the differences in sonic textures we managed to get.  Listen to Schoeps on the Rapid Traverse of the Summit Engine Lathe and then listen to the MKH 60:

REA 004 METAL MACHINES Summit Engine Lathe Rapid Traverse by sepulchra

And listen to do the Headstock of the Vertical Turret Lathe

REA_004 METAL MACHINES Vertical Turret Lathe by sepulchra

There’s a brightness to the Schoeps and darker beefier sound to recording from the MKH.

For the most part, we were successful with almost all of the machines, but in some cases, because of age, they could not be run for a long time.  This meant that in a few cases, we could only get a machine to run for a few takes before it was shut down.  In other cases, because of time, if a machine did not provide much in the way of variation, I moved on after it was covered.  If time is limited, using one’s time efficiently is extremely important.  If something is not doing it for you, move on!

A few other highlights were the sounds from the McCable Flanger:

REA 004 METAL MACHINES McCabe Flanger by sepulchra

It is a machine that has clamps that is controlled by different air pressure tanks and there were also several machines that were belt driven:

REA_004 METAL MACHINES Metal Planer by sepulchra

The way the belt both rattles and flaps around creates such great textures.


Ultimately, I’m very happy with the results that exist in Metal Machines.  You always want more time then you get!  These are sounds that may not exist for long in this country.  In general, these machines are in very limited use, and there will be a point where they won’t be in use at all. I’m glad to not only record a library, but to provide recordings that will serve as historical documents.

More info at Rabbit Ears Audio |Q&A at Designing Sound