A reader who's never heard of you needs a different letter than one who's already familiar with your brand, and conflating the two audiences weakens the copy for both.
Cold Audiences Need More Context and Credibility Building
A reader with no prior relationship to you needs the problem, your credibility, and your solution established more thoroughly before you ask for anything.
Warm Audiences Can Move Faster to the Offer
An existing customer or subscriber already trusts you to some degree, which means the letter can spend less time on credibility and more on the specific offer.
Match Tone to the Relationship
A cold letter often benefits from a slightly more formal, explanatory tone, while a warm audience can typically handle a more familiar, conversational one.
Next step: Use the Sales Letter Writer to draft two versions of your letter tailored to a cold audience and a warm one.