Q: I read your column about the Mass Fidelity Core, the small single-piece Bluetooth speaker that sounds like a pair of speakers placed 8 feet apart. If you were to pair the Core with its wireless subwoofer and Relay Bluetooth digital-to-analog converter, where would you rank the quality of sound compared with bookshelf speakers you recommend, such as the Aon models from GoldenEar?

A: I should first mention that so far I have heard only preproduction samples of the Core. Performance of production models may vary slightly, and I will file a follow-up report once I have heard them. The bright side of this is that my Mass Fidelity contact, who has always been straightforward with me, assures me that the production samples are even better.

In my column, I said that the Core sounded as good as any $600 bookshelf speakers I've heard. The GoldenEar Technology Aon 2 and Aon 3 are my favorite bookshelf speakers, but they play in a somewhat different league than the Core. They cost more — $799 and $999 per pair, respectively — and need an amplifier or receiver to power them. They will also play much louder and more effortlessly than any portable speaker.

This is not meant to take anything away from the Core. If you are looking for sweet sound, the Core definitely has it. Given the way it impressed me, I think that most people who do not work in the industry are likely to be shocked and pleased when they hear the Core for the first time. You just happened to pick some extremely tough competition when you asked your question. As I said in my earlier column, the Aon speakers can reproduce deeper bass, although adding the Mass Fidelity wireless subwoofer to the Core will go a long way to covering the bass aspect for you.

I own a Mass Fidelity Relay and count myself as one its biggest fans. For those who are unfamiliar with it, the Relay is an ultra-high-quality Bluetooth receiver and digital-to-analog converter that is used to add streaming audio capabilities to conventional sound systems lacking built-in Bluetooth or wireless connections. Although I am a fan, I would try the Core on its own before spending another $249 on a Relay to use with it. I connected my iPhone 6 Plus to the Core via Bluetooth and did not find the performance or sound quality to be lacking in any respect. If you have a high-end sound system and want to add Bluetooth to it, I strongly recommend the Relay.

The Mass Fidelity Core is $599, with preorders starting at $449. See it and the Relay at www.mass fidelity.com.

Just add Bluetooth

Q: I have a Denon A/V receiver that has HDMI as well as several digital and analog connections, but no Bluetooth. Overall I am happy with it, but I really want Bluetooth. What would be a good receiver in the $600-$800 range to replace it?

A: If Bluetooth is all you need, I would not spend that much money on a new receiver. You can add Bluetooth using the Mass Fidelity Relay, listed above. There are less expensive options available also, such as the Outlaw Audio BTR-100, which is only $39 (www.outlawaudio.com).

Send questions to Don Lindich at donlindich@gmail.com. Get recommendations and read past columns at www.soundadviceblog.com.