Closer Examination

At first sight the BitHead looks kind of odd with the big rubber battery door, LEDs, and what not. After taking a closer look at it, it becomes clear that there has gone a considerable amount of thought into just why it is shaped like it is. Take the battery door for example, made of rubber it is easy to remove and makes whatever you put on top of it stay in place like a DAP or other portable device. The main body of the amplifier is made of textured plastic.

As far as color choice goes you can get the unit in both clear like the one I got for review and a black version. Besides the color option the internal DAC is also an add-on, the same amp just without the DAC is dubbed the Total AirHead. They both look exactly alike apart from the print.


On the front of the amplifier you find the volume pot, on and off switch, and crossfeed switch. The Total BitHead has dual output which means that you can hook up two cans to the amplifier and listen to the same source. Of course the headphones have to be alike in characteristics, otherwise it will be hard getting the volume right and the sound quality will not be as good.

The green LED on the front of the amplifier indicates whether it is on or off. The red one on the other hand is a clipping indicator LED. This can be very useful because it means that the unit will let you know when your batteries no longer can provide enough juice for the amp to function properly. When running the amplifier directly from a PC both as audio and power source the green LED dims a bit because a PC does not provide the same current as the four AAA batteries do. Since the supplied voltage is lower you cannot run your headphones as high without clipping. With some phones like Sennheiser HD 650 you will only able to run them off batteries because your PC cannot provide enough juice. This is only the case with extreme power hungry cans like the Sennheiser HD 580/600/650 or AKG k701.


All of the switches on the front of the amplifier feel quite solid. Overall the Total BitHead is a very thoroughly built piece of kit.


Just to avoid any confusion, there is a small logo on the rubber door with pictograms imbedded so that you know what the switches and jacks are for. The rubber door is quite easy to peel off. All you do is grab the top of the door and then pull it up and down against you. Once removed you gain access to both the gain switch and the battery compartment. The battery compartment is sealed off so that in the event of leaking batteries the chances of them causing damage to the print are very slim.


This little gadget can be run off any type of PC without drivers! You simply hook it up via a USB to mini-USB cable and it is instantaneously recognized as a "USB Audio Codec" by Windows. Once Windows has figured out what you have hooked up it is ready to use. With the power switch in the off position the amplifier and DAC is run off the power being fed via the USB port, however, if you switch it over to the "on" position, the DAC and amplifier will be run off the batteries further reducing unwanted noise. Even with it being run directly off my stationary PC the noise floor was really low, but it did actually drop noticeably when running it off batteries. Since the DAC is a pretty ordinary Burr-Brown one you can probably get this unit to function under most Linux distributions.


The Total BitHead is a dual purpose device since it can both serve as a DAC and a dedicated headphone amplifier. When using it as a headphone amp you can only run it off the batteries. The crossfeed filter is still applicable and can be used to alter the sound. You can pretty much use any type of source with it as long as you feed the unit through the mini jack on the back. In the package you get a small mini to mini interconnect which can be used to hook up a MP3 player or PMP to the amp. When hooking up your gear to the amplifier it should be turned off to prevent damaging the amp.


The HeadRoom Total BitHead allows you to connect two headphones to it simultaneously which is a great feature if you want to let a friend listen in on what you are hearing. The sockets are not that solid because they are only fixed to the PCB and not to the hard casing shell. The durability is good enough and when put to the test I am sure that the connector on your headphones will break before the sockets on the amp do.


The mini to mini interconnect supplied with the Total BitHead is actually pretty good. It features two right angled connectors and is of a solid construction.


The amp design is quite complex because you have both a DAC and amplification circuitry for two outputs. That combined with a crossfeed filter means that the PCB is well filled out. It is clear that a lot of work has gone into compressing all of the features onto a relatively small footprint. The Burr-Brown DAC used is only 16-bit and does of course have an effect on the resolution of the sound, and the theoretical dynamic range. That being said I much prefer a good 16-bit DAC than a bad 24-bit. Burr-Brown has a good reputation and the DAC certainly does a good job at reproducing music.