converting string to array - Ruby on Rails

I'm trying to convert a string to an array. The method I'm using seems to be working but when I check with pry it's still a string. Let me show you my method and output and see if you can tell me what's wrong. Thank you.

Method:

  def filters=(filters)
    if filters.is_a?(String)
      filters = filters.split(",")
    end

    list = Set.new

    Array.wrap(filters).each do |filter|
      filter.tr!(",", " ")
      filter.strip!
      list << filter unless filter == ""
    end

    super(list.to_a)
  end

View

in the text field I placed hey, ohh

  <%= form_for @integrations, url: url_for(:controller => :integrations, :action => :update, :id => @integrations.id) do |f| %>
   <%= f.label :filters %>
   <%= f.text_field :filters, class: "filter-autocomplete" %>
   <%= f.submit "Save" %>
  <% end %>

Controller

    def update
    @integrations = current_account.integrations.find(params[:id])

    if @integrations.update_attributes(update_params)
      flash[:success] = "Filters added"
      redirect_to account_integrations_path
    else
      render :filters
    end
  end

  def filters
    @integrations = current_account.integrations.find(params[:id])
  end

if you put a pry on the end of that it seems that it has converted to an array. but when I check the object it still remains a string.

when I look at my filters now in the console they look like this

"[\"Hey\", \"ohh\"]"

when I want it to look like:

["Hey", "ohh"]