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MSB Clock Header
The UMT offers an amazing opportunity to install the lowest jitter clock in the world and use it to clock our data going to non MSB
DACs with depend on the incoming data stream to recover the clock.
The standard MSB Clock Header allows both the Femto140 Clock and the Galaxy Femtosecond Clock to be installed. It is user installable.
Just plug it in and the UMT will detect it and start using it.
External Clock Interface
The UMT is truly flexible when it comes to clock interfaces. A clock BNC connector is provided which can be used as an external 512x
clock in or out. This impressive clock port will accept and use an external clock if the clock is present, and if it is the right frequency.
If the clock is not correct or not present, the internal clock will be used. This assures seamless operation.
Now just a comment about clocks. A master clock is 512 times the base sample rate. So a 48 kHz DVD needs a master clock of 24.576
MHz. This is not the same clock needed for a CD. So you cannot really just add an external clock and expect everything to be great.
The clock must be changed to match the material being played. How does the clock know? It doesn’t. This is what is so clever about
the ProI2S interface. The UMT starts out using its internal clock to read the media. Once the sample rate of the material is established,
the UMT tells the DAC and the DAC switches its internal clock to match the UMT and then sends that clock back to the UMT. It senses
the new incoming clock and seamlessly merges to the new clock. But with our clever automatic clock switching, you can hook up an
external clock for CDs for example, and when a CD is played, the external clock will be used, but when DVDs are played, the UMT will
see that the external clock is the wrong frequency and will just use the internal clock instead. Totally seamless.
This clock interface can also be configured to output the current master clock. So you can see that a better option would be to set the
UMT clock interface as an output and send the low jitter master clock to the DAC, provided that the DAC has the ability to accept an
external master clock.
Again, just for clarity, we are talking about a master clock, not a word clock. A word clock is at the sampling rate of the media and will
have to be multiplied up 512 times to make a useful clock inside a DAC. This is a poor alternative. We do not support word clock in
or out of the UMT.
DEFAULT CLOCK PORT: INPUT
TO SET CLOCK PORT TO OUTPUT: On the remote press: <DIMMER> <DIMMER> <DIMMER> <0>
TO SET CLOCK PORT BACK TO INPUT: On the remote press: <DIMMER> <DIMMER> <DIMMER> <9>
Power Connection
The UMT must be connected to a 12 VDC supply with a 5 pin DIN connector. But that is just the basic requirement. The quality of the
power supply directly affects the quality of both the audio and video. The UMT is unique in having the option to use either one or two
power supplies. Basically when power is detected on the second power connector, the grounds and power supplies are disconnected for
the audio and video processing. This is an automatic function. When the power is unplugged from the second supply, the video and
audio are again combined. The second supply becomes the AUDIO supply and should be of the highest quality. This is very important
even if you are not using video with the UMT as the drive, and drive controller and video processing still takes place to some degree
even if video is not used and can corrupt the audio by coupling noise through the power supply connections.
You have many options here.
First of all, all DAC IV Power Bases have a transport power supply included. It can be used for either audio or video.
One or two separate medical grade switching desktop supplies are offered and can be used for either audio or video.