How about passing the smallest and largest arguments to wp_tag_cloud() and making them both the same?
<?php
wp_tag_cloud(
array(
'taxonomy' => 'channels',
'smallest' => '1',
'largest' => '1',
'unit' => 'em',
)
);?>
Update: use get_terms() to get multiple taxonomy terms:
<?php $terms = get_terms(array('channels', 'stations'));
if (is_array($terms)) : ?>
<ol>
<?php foreach ($terms as $term) : ?>
<li><a href="https://wordpress.stackexchange.com/questions/56312/<?php echo get_term_link($term) ?>"><?php echo $term->name ?></a></li>
<?php endforeach; ?>
</ol>
<?php endif; ?>