The Plantronics Discovery 645 Ultimate DSP

Plantronics, Inc. introduced the first lightweight communications headset in 1962 and is today a leading designer, manufacturer and marketer of lightweight communications headset products. Plantronics headsets are widely used in many corporations and have been featured in numerous films and high profile events, including the historic landing on the moon in 1969. On this mission a Plantronics product was used for the transmission of Armstrong’s memorable words on his first stepping onto the moon’s surface. Today we won’t be reviewing that headset, but something much newer: the Plantronics Discovery 645 Ultimate DSP Bluetooth Headset. Read on to see what I think about this product. The Plantronics Discovery 645 Ultimate DSP Bluetooth Headset (Discovery 645) is Plantronics’ top-of-the-line non-stereo Bluetooth headset and it’s just a step down from their flagship Pulsar 590A Stereo Bluetooth headset and a step up from the Discovery 640. The 640 and 645 models look externally the same, but there are a few differences. Compared to the 640, the 645 model has Plantronics Digital Signal Processing technology that reduces background noise for improved listening and has a lower talk time of up to 3 hours (up to 9 hours with AAA charger) compared to the 640’s 15 hour talk time. The Discovery 645 also has been given the Bluetooth 2.0 certification while the 640 adheres to the Bluetooth 1.2 spec. Compared to the 1.2 version, Bluetooth 2.0 offers 3 times faster transmission speed (up to 10 times in certain cases), lower power consumption through a reduced duty cycle, simplification of multi-link scenarios due to more available bandwidth and further improved BER (bit error rate) performance. The BER is very important in the case of a headset as it comes down to improved audio.
I expected that this product would have the Bluetooth 1.2 specs, so I was positively surprised that Plantronics gave it the Bluetooth 2.0 treatment, very nice!

Before we continue, let’s have a look at the features:

  • DSP (Digital Signal Processing) actively reduces background noise for improved sound quality
  • Less to carry – use your existing mobile phone charger for up to 3 hours of talk time between charges
  • A unique, pen-sized carrying case stores a AAA battery that charges the headset between calls – a Plantronics industry first – for up to 9 hours of talk time
  • Innovative pocket charger stores a AAA battery the charges the headset between calls
  • Ultra-light 1/3 ounce weight, customizable gel ear tips for long-wearing comfort
  • Sleek, lightweight wireless design with chrome finish carrying case
  • Vibrate ring in charging pocket, last number redial, and voice dialing
  • Long-wearing comfort and ultra-light – weighs only 1/3 ounce
  • Personalized fit with three sizes of soft gel ear tips
  • Optional ear stabilizer – fits over the ear
  • Sleek, lightweight wireless design with chrome carrying case
  • Supports last number redial, and voice-activated dialing2 for easy mobile use
  • Pocket case vibrates with incoming calls
  • Works with multiple Bluetooth devices – phones, PDAs or laptops
  • Freedom to roam up to 33 feet from your Bluetooth device
  • Design/package

    The Discovery 645 comes in a simple black/blue/white box with a clear front showing the headset and some of its accessories. In my opinion this box doesn’t do this product any justice. A box with faux metallic paint would look much nicer and continue the overall look of this product, but most people end up throwing the box away so it’s understandable. But once you do open the plain box you are in for a big surprise. With products like this, it’s all about presentation right? Well, Plantronics has kept this thought in mind it seems, when designing the Discovery 645. It comes with a classy metal casing that allows you to carry the plethora of included accessories, but there is no place for the AC power Adapter. There is a reason for this and will be explained later on. The case exudes class and feels very sturdy and has the same metallic finish with glossy black accents as found on the headset. The metallic with glossy black finish is used on the headset, casing and accessories, adding to the uniformity of the package. I was surprised to find a mirror at the bottom side of the case, not essential but a nice touch. Most manufactures include anything but the most basic of accessories, this way you’ll have to pay more later on. Plantronics has decided to go the other way and include every possible accessory imaginable for a headset. Checking on their site it seems that the car charger is the only optional accessory. I think other manufacturers should do the same and release these all-in-one packages. Styling is a very subjective matter, but overall I think the headset looks really classy and most people I asked tended to like its design. I also liked the inclusion of the carrying case, this way you don’t have to have the headset in your ear all the time. So what can we find in the package? Included in the case are:

    1. Headset
    2. Headset Carrying Pocket
    3. Battery Charger
    4. Battery Holder
    5. Battery (AAA)
    6. Charging Adapters for Nokia, Sony Ericsson, Motorola, Motorola Razr
    7. Detachable Ear Stabilizer
    8. Soft Gel Ear Tips (a: Small, b: Medium, c: Large)
    9. AC Power Adapter

    The headset looks simple; this is due to buttons being integrated into the design:

    1. Indicator Light
    2. Call Control Button (On/Off)
    3. Volume Control (UP/Down)
    4. Soft Gel Ear tip
    5. Microphone


    Before using the headset I had to charge it and as a matter of fact there are three ways you can charge the Discovery 645. You can put the headset in the carrying pocket and use the included AC power adapter or you can remove the AC adapter and attach the battery charger. This is convenient as you can charge the headset while you’re on the move or where there is no power outlet. When the battery charger is connected to the carrying pocket it will vibrate to notify you of incoming calls. I would have liked if Plantronics included a rechargeable battery so that when the entire unit is connected via the AC adapter, the battery in the optional battery charger would also be charged. Another thing is that the unit only vibrates when the battery charger is connected. It would have been better if the vibrating function was also integrated into the carrying pocket and that it would run of the batteries of the headset itself. But this is a minor problem, because when the battery charger is attached the entire unit, it?s about the size of a pen. that you can attach to your shirt pocket, pants or tuck away neatly in your purse. This way you don’t have to look silly and walk around with the headset in your ear while not attending a call. The last method of charging is handy for travelers as you don’t have to take the AC adapter for your cell phone and headset. This is also the reason why there is no place for the charger in the case. When going on trips you already take your mobile phone?s charger. All you do is attach the appropriate charging adapter and charge the unit using your mobile phone’s charger. I am very impressed with the various charging option and good thing is that it’s all included as standard.

    Daily Usage

    Using the headset is fairly easy: you turn it on by holding the call control button until it lights up blue, and hold it again for 6-8 seconds until it beeps twice and lights up red. You raise and lower the volume by pressing the up/down volume key. Before usage of course you have to pair the devices using the standard ‘0000’ passkey. For those that want more control it also allows you to mute a call, use voice dialing, reject a call, switch a call from phone to headset and the other way around. You can also disable the DSP function to extend talk time.

    The headset feels comfortable in your ear and Plantronics does include three sizes of the gel ear tips, I found that the medium ear tip works best for me. The headset did stay securely in place, I tried to see what it would take for it to fall, but no matter what I did it stayed securely in place. The included ear stabilizer felt uncomfortable, but without them it really is hard for them to fall out accidentally. Of course the headset can also be used both in the left and right ear. When you receive a call it will pulsate between blue and red and you can answer the call by pressing the call control button or end the call by pressing the same button. If the headset happens to be in the carrying case with battery charger attached it will vibrate and pulsate the light. Taking it out of the carrying case will automatically answer your call. The caller’s voice came through loud and clear and the caller noted the same thing although it did sound throaty. While driving with the windows open the caller also noted that he didn’t hear much of the wind, so obviously the DSP is doing its job. But of course there is only so much it can do: it will lower environmental noise, but not completely eliminate it.

    I also tested the headset by paring them to my PC and using it as a headset to do some voice chatting on Windows Live Messenger and Skype. In this test it also worked flawlessly: I could easily walk around the room while talking away. Noteworthy is that the range is much lesser then the advertised 33 feet, admittedly I was testing it in a building with many walls.


    The Plantronics Discovery 645 Ultimate DSP Bluetooth Headset is a great headset with acceptable range and excellent voice quality. The DSP effectively blocks out some environment noise but allows the 640 model without the DSP to have a longer talk time.

    The overall quality, fit, finish and presentation is excellent and above most headsets available today. The design is discrete and really classy. I am impressed at how Plantronics handled the charging options, something that other models can?t do, even with optional equipment. There are a few things we would like to see: inclusion of the vibrating function without the battery charger. On the other hand if they did include such a vibrating function in the carrying pocket, it would constantly be running of the headset’s battery, and with a lot of phone calls you could end up with a low running headset battery, so it is a fair trade for now. Although the battery in the headset is rechargeable, the one used in the battery charger is not, adding another rechargeable battery would be nice. The carrying pocket and case are a nice idea, in future versions I would like to see more carrying options like in the form of a neck strap, so that you can carry it in the form of a necklace. This is a good headset and personally I have been using it as my main headset. It gets a well-deserved 9 out of 10.


    All-in-one package
    Multiple charging options
    Quality fit and finish
    Stylish and tiny headset
    Vibrating option (with battery charger
    Excellent audio quality and the DSP effectively improves sound

    No vibrating function while in carrying pocket
    Needs a higher volume in some situations
    Longer range needed

    Written by Devin