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Dangerous Music 2-Bus Manual

10

Sometimes problems that sound like ground loops are caused by other situations. These
require trouble shooting beyond the scope of this section and a qualified technician may
have to make a visit if help is needed.

Expansion Inputs and Connector Pin-Outs

The 2-Bus has an expansion input port that allows connecting other 2-Buses and 2-Bus

LT

’s, to increase the system size and capability. The 25-way ‘D’ connector on the rear

panel labeled 

REM/EXP

 is used for this purpose. The REM/EXP port is wired according

to the following chart. A pre wired expansion adapter for the 2-Bus is available when
multiple units are bought or additional units are ordered for a facility already using one.

Pin#     function           

10

right + 

23

right – 

11        right shield      
24

left +

12

left –

25        left shield        

All the XLR connectors are pin 2 hot.

Pin 1    shield               
Pin 2    + signal           
Pin 3    - signal              

So far, we have not seen Pin 1 hot (+), except after too many drinks…

The AC Mains cable

The mains cable uses a standard IEC connector. 

Please check the mains voltage

selector (the little red window next to the IEC connector on the power supply) to
make sure that it is correct for your location.

 The fuses for the voltage selection block

are _ ampere, fast blow AGC type. 

PLEASE DON’T PUT A FUSE OF LARGER

RATING IN THE BLOCK!

 

Disconnect the mains cable before changing the voltage

or replacing a fuse.

 If a fuse blows repeatedly, this is a sign from Mother Nature that

something is wrong and the factory should be contacted for help at the link provided on
the Specifications page.

Please use pre-wired AC cables for this device unless a technically qualified person
makes the connections to a mains plug.

 In this case, use only high quality mains plugs

like 

Hubbel

Thomas & Betts

, or similar. Remember, in America, Black is hot, White is

neutral, and Green is ground. In Europe, Brown is hot, Blue is Neutral, and Green with a
Yellow stripe is ground. It is critical to get this correct. 

Double check that it is!

Summary of Contents for 2-Bus

Page 1: ...possible by careful design construction and top shelf component choices by recording industry veterans This manual will assist the user with installation of the 2 Bus as well as calibration of the sy...

Page 2: ...large power supplies at least several rack spaces if not in a different rack away from equipment that deals with low level signals Separation of high level and low level equipment can pre empt troubl...

Page 3: ...p The 2 Bus is designed to mix the outputs of up to 16 D A converters to any stereo recorder 16x2 The 2 Bus is easily stackable to increase channel numbers and system functions when linked with other...

Page 4: ...sing if desired and then the 2 Bus This mix has 8 tracks of drums one bass two guitars one vocal with reverb and effects for maybe 2 dozen tracks total Usually a DAW user would mix this to 2 tracks an...

Page 5: ...istent mix results will be obtained if this is done There are two levels that most digital recording systems have seemed to converge on depending on whether the situation is for recording or mastering...

Page 6: ...to offer In other words A D s are set to avoid clipping for recording and D A s are set to avoid overloading the mixdown converter This is done by aligning one D A at 18dBfs and using it to calibrate...

Page 7: ...tage of the 2 Bus Signal gets through and the grounds stay put inside their respective pieces of gear Unbalanced Audio Connections An unbalanced source driving a 2 Bus input usually presents no proble...

Page 8: ...zz troubles in a recording studio While the techniques are not meant to be taken as Gospel some techs might disagree with this treatise so be it these bits of knowledge were gleaned from decades of ex...

Page 9: ...ny variables but can go from unnoticeable to raging Some people in desperation resort to using AC plug ground lifts to defeat the mains safety grounds in a random fashion until the system quiets down...

Page 10: ...e have not seen Pin 1 hot except after too many drinks The AC Mains cable The mains cable uses a standard IEC connector Please check the mains voltage selector the little red window next to the IEC co...

Page 11: ...Hz Noise floor 83 dBu audio band limited Maximum signal level 27dBu Nominal operating level 4dBu Input impedance 12k ohms bridging Output impedance 50 ohms Gain accuracy 0 02dB for any setting Power c...

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