Investors interested in stocks from the Communication - Components sector have probably already heard of Turtle Beach (HEAR) and Acacia Communications, Inc. (ACIA). But which of these two companies is the best option for those looking for undervalued stocks? Let's take a closer look.There are plenty of strategies for discovering value stocks, but we have found that pairing a strong Zacks Rank with an impressive grade in the Value category of our Style Scores system produces the best returns. The proven Zacks Rank emphasizes companies with positive estimate revision trends, and our Style Scores highlight stocks with specific traits.Turtle Beach has a Zacks Rank of #2 (Buy), while Acacia Communications, Inc. has a Zacks Rank of #3 (Hold) right now. This system places an emphasis on companies that have seen positive earnings estimate revisions, so investors should feel comfortable knowing that HEAR is likely seeing its earnings outlook improve to a greater extent. But this is only part of the picture for value investors.Value investors also try to analyze a wide range of traditional figures and metrics to help determine whether a company is undervalued at its current share price levels.Our Value category highlights undervalued companies by looking at a variety of key metrics, including the popular P/E ratio, as well as the P/S ratio, earnings yield, cash flow per share, and a variety of other fundamentals that have been used by value investors for years.HEAR currently has a forward P/E ratio of 7.75, while ACIA has a forward P/E of 29.32. We also note that HEAR has a PEG ratio of 0.86. This popular metric is similar to the widely-known P/E ratio, with the difference being that the PEG ratio also takes into account the company's expected earnings growth rate. ACIA currently has a PEG ratio of 1.58.Another notable valuation metric for HEAR is its P/B ratio of 2.68. The P/B is a method of comparing a stock's market value to its book value, which is defined as total assets minus total liabilities. By comparison, ACIA has a P/B of 3.77.These are just a few of the metrics contributing to HEAR's Value grade of A and ACIA's Value grade of D.HEAR sticks out from ACIA in both our Zacks Rank and Style Scores models, so value investors will likely feel that HEAR is the better option right now.Want the latest recommendations from Zacks Investment Research? Today, you can download 7 Best Stocks for the Next 30 Days. Click to get this free report Turtle Beach Corporation (HEAR): Free Stock Analysis Report Acacia Communications, Inc. (ACIA): Free Stock Analysis Report To read this article on Zacks.com click here.