Hundreds of thousands of customers have purchased a Sleep Amplifier® mattress as their first mattress, when moving into their first apartment, or when they simply need a mattress that is both affordable and supportive. Great, basic components. Appealing ticking. Every day comfort. That’s Sleep Amplifier®. The Sleeptastic Firm is a 7.25” thick mattress with a firm quilted top. It features edge-to-edge inner springs for support.