I read with interest Craig Brougher's article on Bob Hunt's Virtual
Roll system ( http://www.player-care.com/virtual-roll-player.html ).
After giving up on selling my E-Roll Player, I still sell E-rolls for
Ampico, Duo-Art and Welte and am very pleased that Bob is selling his
system successfully.  I installed one of his early systems and found
it to be quite easy to install and well designed.  I'm sure his current
production is even better.

As Craig states, he did install several of my systems and other than
the one problem he mentions, I am also not aware of any problems.
I am easy to contact so I assume that there are no problems with
installed systems.  The first model used electronics designed by
Gene Gerety which did use very sophisticated electronics and was not
especially easy to program.  In spite of this, the units have proven
to be very reliable once installed.

When I started making the systems on my own, I replaced the electronics
with a very simple design.  I designed the valve drivers myself and
had the MIDI controller designed by John Wale.  This design is just
a customization of his well proven product.  Both the valve drivers
and the controllers have proven to be completely reliable and easy to
install and program.

Unfortunately the most important component of the new valve board
design became obsolete (thank you, Texas Instruments!) forcing me to
stop production.  A couple of years later, the part was reinstated but
since Bob is making his system, there is no reason for me to compete.

The original seats that had a leakage problem were made of silicone
rubber which I chose because of its long life, not because it was a
cheaper material.  It proved to be too troublesome.  I could not find
anyone to make the washers because of their small size and required
precision and so I had to make them myself.  No one wanted to make a
cut washer of this size.  I could have had them molded but this would
have cost thousands of dollars just for tooling without any guarantee
that they would even work.  The original silicone washers work well but
they need to be hand selected, which made testing very time consuming.

The problem with silicone is that it has a surface skin which makes
it very difficult to punch reliably.  Some washers come out flat but
others have a slight curl.  Until they were mounted and installed in
a valve block there was no way to tell if they would leak.  The new
rubber compound which is a mixed EPDM/neoprene punches reliably.  The
only downside is that they might last only 20 years as opposed to 50
to 100 years for the silicone.

I have both EPDM and silicone washers for anyone who wants to try them.
I recently threw out a large number of silicone washers because there
was no demand for them but I do have some if anyone wants to try them.

The one known material problem I had was a batch of silicone adhesive
that cured in a way that allowed it to become sticky months or years
later.  There was no indication of a problem until I noticed sticking
in one of my systems.  The silicone in question was the best material
available and came from a reliable supplier.  I have no idea why one
batch had this problem but I discontinued the use of this adhesive in
future productions.

Instead of using cured silicone as an adhesive/bumper, I replaced it
with piano felt bumpers.  All later production units have these bumpers
and will not have sticking problems.  I also designed a simple retrofit
for the older systems.  If anyone has an older system (contact me to
determine if this may be a problem with your unit) I can provide the
retrofit parts or install them in valve blocks returned to me.  I am
pretty sure that this problem effected just a small number of units
made from a single tube of adhesive.

Best regards, Spencer Chase
Garberville, California
http://www.spencerserolls.com/