Pioneer Deh-6000 Essay, Research Paper

In today?s society many products are released into the market without first going through a proper evaluation phase. Designers must take into account the needs of the user by inviting prospective consumers to evaluate their products and to point out improvements in the interface or design. When designers fail to incorporate the user?s needs, the product?s economic success is in serious jeopardy. If the product is too hard to operate then the consumer may opt for a better version, often looking toward the competition to have their needs met. In order for a product to be successful in today?s market, user-based evaluation must be incorporated in the design process.

This paper will critique the interface design of the Pioneer DEH-P6200 in-dash CD-player. Pioneer has revolutionized the car stereo industry with its latest line of CD-players. The DEH-P series offers the user with all the functions of a regular CD-player along with some added components and extras. Each in dash car stereo in the series includes a multi-depth CD-player (8cm and 12cm), car alarm, equalizer and a built in sub-woofer amplifier all in one. Unfortunately, all the extras included in the DEH-P6200 add functionality, which in turn requires increased time for learning and much more for the user to commit to memory. Intermediate to advanced car stereo users, those who have owned or installed a car stereo, should have no trouble learning to operate the DEH-P6200. Due to some failed design conventions many first time car stereo users may struggle and may not be able to operate this device at all.

At first glance the user may have trouble finding the most important button, the main power button. Located near the lower left side of the interface, the power button is a small round button labeled ?SOURCE?. The button has a green illumination, which catches the users attention, but size and location seems to decrease this button?s ease of use. Since this is one of the most important functional buttons, it could be larger and more visible. The designers probably choose to label this button ?SOURCE? because the button also controls which source is currently being used – CD, tuner, or changer-control. First time users would greatly benefit from separate buttons for changing the source and switching the power on and off.

The ?SOURCE? button, once the power is on, allows the user to switch between the 3 different modes of the CD-Player: CD, tuner, and changer-control. The interface also allows the user to switch to the equalizer from any of the main three modes. When switching between the different modes, the color of the light around the Master Volume Control changes to help the user determine which mode they are currently in. If the user switches to equalizer mode the light changes to blue, which coincides with the blue display graph of the equalizer just to the right of the volume knob.

Feedback is a very important factor, and this control does rather well. Every time the button is pressed, a soft tone is played to let the user know that he/she has properly pressed the button. When used for the on/off function, the stereo?s interface lights up when the button is pushed which makes it easy to determine the state of the unit. The trouble comes when the user wants to turn off the unit. The ?SOURCE? button must be pressed and held for 3 seconds to turn the device off. The user has no way of knowing this unless he/she has read the instruction manual or has any prior knowledge about car stereos.

Every button on the DEH-P6200, when pressed, has some sort of feedback. The designers have even incorporated different tones for volume up or down, as well as separate tones for each equalizer preset. The best example of feedback that can be seen in this model is the auto-scan function on the tuner. When the user presses and holds down the scan button, a small tone is played each time to tell the user to let go of the control. If the button is held to long a series of beeps let the user know they have done something wrong.

Another main control is the Master Volume Dial, which is the circular knob located near the left side of the interface. Like most car stereos, Pioneer has chosen a round knob that affords turning either left or right. This button, like the source button, is also a multi-purpose button. It controls the master volume as well as all of the different presets for the equalizer. To switch back and forth between the volume and equalizer control, the user must push the center of the knob. There is a small circular depression to let the user know that this button affords pushing. The designers have obviously failed to properly label here, this can cause problems because the user may never push the button and the equalizer settings may never be discovered.

The master control knob is very visible to the user, but problems may arise because of improper mapping and labeling. It?s hard to tell, at first glance, which way to turn the volume control to increase the volume. There is however, a small arrow just above the control that points in both directions to show the user how the button may be turned. The arrow pointing up to the left would indicate that turning the knob to the left would increase the volume; this however is not the case. Here the designers could have labeled both sides of the knob with a ?+? or ?-? in addition to the arrows to let the user know which way to turn the knob without any prior knowledge. Even so, a better way to would have been to design the master volume switch with an up and down arrow like the DEH-P6000. If a design team has followed proper design conventions, the user should be able to know what the results of their actions will be before any action actually takes place. Here the user can only predict the outcome, and may in some cases, develop a false mental model for this control.

The last major functional control is the Menu Selection Device, or the menu control. This particular control is used after the user has pressed the audio control button, labeled ?AUDIO?, located at the bottom right of the interface. The current settings to be changed will be displayed on the screen, for example ?Alarm On? would indicate the built-in alarm has been turned on. Each press of the audio button, also accompanied by a tone, will change the function to be controlled. In order to change the settings for each function, the user must press either the up arrow, or the down arrow. The left and right arrows control the different settings of each function, for example the equalizer function has adjustments for low, mid, and high. The user can scroll left or right, and adjust each setting up or down, allowing the user complete control of all the different features the DEH-P6200 has to offer.

The designers of this particular system have taken into account errors which users are prone to. Most errors that occur with this model tend to be slips. The Master volume knob may cause errors due to it?s multi-function control. If the user wants to increase the volume when the system is in equalizer mode, he/she must first press the button in order to switch back to volume control. The user may cycle through the equalizer presets instead of adjusting the volume. In order to eliminate some errors, certain functions are disabled when the system is in different modes. For example, when the system is switched to tuner mode, the row of buttons along the bottom (Labeled Station Presets) illuminates and becomes active. The user knows that the pre-set station functions have now become available to use in the current mode.

Every user, whether they are new or experienced, develops some sort of mental model when using this device or any other device. Pioneer has developed an interface which builds on the users existing knowledge. With prior knowledge the user can develop a more correct mental model, and this is why the device may be hard to operate for first time users. Inexperienced users may develop a sort of taught helplessness because of all the added extras and multi-function controls.

The best feature of the Pioneer DEH-P6200 is the display. Clearly visible, it? the large readout center located in the middle of the interface. The text in the display lets the user know what function they are controlling, or the title of the current disc. Everything within the display is color coded so the user can easily distinguish between the different readouts. The nice thing about the display is that every setting is located near its control. This helps the user to see the right control to use in order to adjust a particular setting. In order to improve the ease of use of the display, the designers could have spaced the readouts a little bit better. The display can sometimes become cluttered with information the user may not need, such as sub-woofer status, and F.I.E (Front Image Enhancer) readout. Older models like the DEH-5800 have a larger display that is customizable so the user can adjust the display?s readout.

Overall, Pioneer?s DEH-P6200 has it?s good points and bad points from a design point of view, like many other car stereos on the market today. Although this critique did not cover all of the controls, it covered the most basic controls necessary for operation. Based on the controls critiqued, the user should be able to form a good conceptual model of the unit that is relatively close to the designer?s system image. At first the user may struggle with the controls, but with time and practice any user can easily master the controls of the unit. Although there are a few places where visibility and mapping could have been improved, the design team at Pioneer has developed a very usable and complete system for avid car stereo users.