Manley BACKBONE Mastering Insert Switcher 2003 - present - Manual (Page 11)

BACK PANEL
As previously described, you have 3 Input XLRs per side followed by an Output XLR that reflects the
chosen input. These are factory set-up as AC coupled (the inputs are protected by capacitors, which may prevent
some clicks or pops when switching), which implies the signal has to flow through capacitors. If these capacitors
are unwanted, there are jumpers (no soldering required) to bypass them and provide DC coupled inputs (similar
jumpers exist for the outputs). The diagram describing the jumper locations is on page 23.
Next are Multi-Pin connectors that handle all of the INSERT inputs and outputs. The BACKBONE uses
EDAC/ELCO 56-pin connectors. There is also an option for DB-25 connectors, if one so desires. Both of these
systems are very reliable and allow for pretty bulky audiophile wires that many mastering engineers prefer. Are
these wired to the “industry standard”? Close, but not exactly. The big difference between the industry stan-
dard and what the BACKBONE uses has to do with the XLR “sex”. The standard may have either all male or
all female XLRs, while what you need here is half male, half female. So, worst case scenario, buy one of each
‘standard’ cable, and spend an hour or two swapping half of the XLRs. Better case scenario, find pre-made ones
that fit the bill (make sure to thoroughly investigate first!). Best case scenario, have a good tech build some au-
diophile wire (maybe silver conductor) cut-to-length, tailor-made ELCO or DB-25 cables. (ELCO pinout is on p.
19, DB-25 pinout is on p. 20)
If you wish to purchase custom cabling for your setup, we highly recommend Rapco Horizon. If you go to
their website (www.rapcohorizon.com), there is more information on their cables, line testers, and various other
products. They build their cables VERY well, they have excellent customer service, and we’ve found their prices
to be quite reasonable.
Next comes an interesting pair of XLRs marked “PATCHABLE”. There are a number of points internally in
the console where these XLRs can be patched. Of course, this means opening up the BACKBONE, opening up
the manual (which is probably open already if you’re reading this), attempting to interpret the map on page 18,
and moving some ribbon cables, but dealing with ribbon cables seems to be par for the course if you’ve had a PC
in your life. The three intended purposes for these are:
- An alternative to the multi-pins for one pair of inserts. You might use those for “producer-processors” or
new gear you are evaluating. In that case, you probably don’t want to have anything plugged into the corre-
sponding XLRs off the multipins. For example, the Manley factory presets that “PATCHABLE” to INSERT
6, so use either the multi-pin Insert 6 XLRs or these. Actually, just watch out for the female XLRs or inputs
because you don’t want the outputs from two different boxes feeding into each other. The alternative set of
male XLRs can be considered a parallel output, so it can feed something. Which brings us to…
- A feed to the monitor controller for checking the processing half-way into the chain. Typically a master-
ing engineer may want to compare the dry signal (“Selected Input” XLR), the analog processed signal (Main
Output 2), and maybe somewhere part way through the processing, which these jacks allow.
- A feed for some of the unusual processing tricks described in the MIX/FADE section on page 15.
Next on the back panel are outputs for SUM and DIF. These are the raw encoded signals (unprocessed by
Insert 2 & 3). These XLRs could be used to send to processors, in which case probably either but not both would
be used. You can also send these signals to VU meters. **Note that the SUM signal is attenuated 6 dB and the
DIF signal is boosted 6 dB, so that with typical stereo music mixes these outputs have similar levels to normal
left and right signals (easier for outboard gear to process).**
After that, you get MIX INPUTS. These feed the FADER in MIX mode. As described on page 15, if you use
these as a return from processing the DIFF signal (but not the SUM), you should get a special Y cable where the
right XLR is wired out-of-phase. There is a diagram of this cable on page 21.
Last is a pair of stereo outputs. One pair generally goes to your main Analog to Digital Converter and the
other goes to the monitor controller or VU meters.
11