The Letchworth Garden City-based business has replaced two older HP models, including an Indigo 3050, and increased the quality of its output with the arrivals.
The 10-staff firm, which was established in 2001, recently used the presses for Tesco, as well as producing security data work for corporate clients.
Howard Digital director Daniel Howard told printweek.com the firm has completed a large volume of short-run work, including personalised corporate records and accounts, with HP's Yours Truly personalisation software.
"In the few months we've had the new Indigo presses, each machine has done more then 1m impressions," said Howard.
He added: "The speed and reliability of the HP Indigo presses allows us to meet and exceed our customers' requirements and tight deadlines."
HP's Indigo 5500 can print up to 68 full-colour pages per minute and has a list price of £285,000.
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