sub new {
    my ($class, %args) = @_;

    $self->_foo($args{foo});
    $self->_bar($args{bar});
    ...
    ...
    ...
    ...
}
sub _foo {
   # essentially these methods are setter/getters with
   # a bit of sanity checking on the param
}
sub bar {
    ...
}
sub ...

##</code><code>##

BEGIN {

    $param_map = {
        channel  => \%mux,
        queue    => \%queue,
        polarity => \%polarity,
        rate     => \%rate,
        mode     => \%mode,
        gain     => \%gain,
    };

    no strict 'refs';

    for my $sub (keys %$param_map) {

        *$sub = sub {

            my ($self, $opt) = @_;

            if (defined $opt) {
                if (! exists $param_map->{$sub}{$opt}) {
                    die "$sub param requires an integer\n";
                }
                $self->{$sub} = $param_map->{$sub}{$opt};
            }

            my $default = "DEFAULT_" . uc $sub;
            my $max     = "MAX_"     . uc $sub;

            $self->{$sub} 
              = __PACKAGE__->$default if ! defined $self->{$sub};

            $self->_bit_set($self->{$sub}, __PACKAGE__->$max);
            
            return $self->{$sub};
        }
    }
}