The Boss DB-90 Dr. Beat is an in depth metronome. I don’t know if this is something that they are still making or not. Even though most people are going to be using a click in the box, it can be beneficial to have something not on your computer, especially if you are using tape at all, which is the setting in which I’ve used the DB-90. For connections it’s got ¼” jacks for ins and outs and an 1/8” headphone jack as well. It also has a MIDI output. There’s a lot that you can do with the Boss DB-90 Dr. Beat that I’ve yet to use it for and don’t think that I ever will have the need to. In the studio where I’ve used this we simply use it as a click when recording to tape. The click sound is alterable but we’ve got it on a nice setting that isn’t too abrasive but still can be heard through a headphone mix. You can tap out the tempo easily as well, which is a huge plus on this. You can even save your sounds and tempos as well as have the ability to loop. There’s probably more that can be done with it, but who really needs to get that in depth? If you do, at least there’s options for you but I think that most of use using the Boss DB-90 Dr. Beat in the modern day will not have a need for anything but the basics. It’s also cool that the DB-90 has it’s own little stand that can sit easily on your desk so you can change click times easily as well as turn the click on and off when needed and tap out tempos to the beat of a song. I don’t really have a clue how much the Boss DB-90 Dr. Beat will run you, but if you need an external metronome from your computer, it’s a fine choice because you’ll have all the basics covered and then some.