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Patchbays - The
Nerve Center Of Your Rack
by Ken
Lanyon (Slider)
Ok, let's be honest here. How many of us have
such a mess of cables behind our gear that we hate to go back there and repatch
something? Say you have this awesome guitar sound and you are about to record a
song to your multitrack. This means that you have to get up, possibly pull some
furniture away from the wall, risk exposure to dustballs...mammoth
spiders...cobwebs, and then search through a spaghetti of wire to find the
correct cable to patch in. How about trying to patch in a compressor over your
entire mix? It's such a pain to get back there, kink your back out, and scrape
your knee on the cabinet just to get some even levels over your mix. Does this
all sound familiar? This is something that I know about first hand, and I
suffered through it for quite a while, as I am sure many of you are doing.
Fortunately there is a simple answer...in the form of a device called a patchbay.
A patchbay is this wonderful, rack-mountable unit consisting of cable jacks on
the front and back. These jacks are aligned in dual rows on top of each other
stretching across the length of the patchbay, with each row generally having 24
jacks. It will be helpful if you think of the jacks exhisting as vertical pairs,
since there is most often an intimate relationship between the two. The purpose
of these connections is to permanently plug in all the gear and inputs / outputs
into the back that you often repatch while recording or mixing. You can then use
short patch cables in front to route the signals to and from all your equipment
where you want them to go. You have now accomplished all of your necessary
patching without even getting up from your comfortable seat in front of the
monitors. Of course, there is a little more detail involved with understanding a
patchbay, so I am going to go into those specifics next.
First of all, there is no standard on how you set up your patchbay. You own the
gear, and only you know how you prefer to work. I will mention that commercial
studios normally designate the top row of jacks as the outputs of your gear and
mixer, with the bottom row then becoming the inputs. This is a helpful tip for
organizing your unit, and is also important when dealing with normaled and half-
normaled jacks. Ok, I know I probably just lost you on that one so I will go
over those terms.
Normaled, Half-Normaled, and Denormaled Jacks When we talk about normaled, half-normaled,
and denormaled jacks, we are really talking about how the signal flows through
the jack itself. This has everything to do with the way the connections are
soldered or connected on the PC board inside the patchbay, but for the purposes
of this article, I will just explain how a jack treats an incoming signal rather
than explain how to solder the connections.
Normaled
Normaled jacks are those where the top jack in back is automatically routed to
the bottom jack in back when the front jacks are not used. For example, let's
say that you have the outputs from your delay unit plugged in the back of the
patchbay into jacks 1 and 2 on the top row (remember outputs on top, inputs on
bottom). Lets also assume that you have the aux returns to your mixer plugged
into the back of the patchbay into jacks 1 and 2 on the bottom row. With no
patch cables used in front, the delay unit is always connected directly to your
mixer via the aux returns, because the top row is internally feeding signal to
the bottom row. There is no need to patch anything in the front because it is
already hooked up. A normaled patch also allows you to connect the outputs from
another unit that is not a member of those pairs into the bottom jacks 1 and 2
in front. Doing this breaks the normal internal connection between the top and
bottom jacks, and now routes the new signal through to the aux returns of your
mixer. Pretty cool!
Half-Normaled
Now, a half-normaled connection is similar to a normaled one, and that is where
a lot of confusion arises. Let me first set up the scenario. Imagine that you
have one output track of your multitrack plugged into the top jack of 3 in the
back of the patchbay. You also have the input to your mixer channel 3 plugged
into the bottom of jack 3 in the back of the patchbay. As with normaled patches,
the top jack of each pair is internally connected to the bottom jack so that in
this case, the output of track 3 is automatically routed to the mixer for
playback. The difference here is that with a half-normaled pair, you can insert
a patchcord into the top jack #3 in the front and the connection to the bottom
jack in back will NOT be broken. This allows you to have two copies of the
output track and bring the 2nd copy into another mixer channel to process
differently while the original goes to its original corresponding mixer channel.
Of course, if you are doing this so that you can route the outputs of track 3 to
another mixer channel other than channel 3, then you have to plug a cord into
the bottom jack in the front and leave the other end unconnected. This is called
dead-patching and the purpose is to break the connection between the back top
and bottom jacks by routing the back bottom jack to the front bottom jack (This
is assuming you only want one copy of track 3 to show up on your mixer).
One situation you would use half-normaling jacks for is when you want to have
two completely different EQ settings on your single vocal track during different
parts of your song. It would be too tough and slow to change the EQ back and
forth during the mix so you can have two separate channels with lead vocals, EQ
them differently, and just mute the one not being used during different sections
of the mixdown. This also allows you to have different effects on your
instruments during different sections.
Denormaled
Denormaled jacks have no real tricks. They are designed to send input from the
top and bottom back jacks directly to the front jacks. That is to say...the back
top jack directly feeds the front top jack and vice versa with the bottom jacks.
The top and bottom jacks do not connect at all internally. Period. Denormalled
pairs are often used to give you a pair of patch points for, example, a signal
processor such as a reverb unit that is not normally inline with your mixer aux
jacks. Your reverb unit is simply plugged into the back of the patchbay to
provide you with convenient patch-in points in the front. This way you can use
short patch cords from these points to process a signal from another point in
your patch bay.
Patchbay Models Thankfully, there are many different models of patchbays
to fit your needs and wallet. They range from having 32-48 jacks (16-24 jacks
per row), and the ability to switch these connections between normaled, half-normaled,
and denormaled varies on the brand of patchbay you buy. Some require soldering
to set it up initially, while most come pre-soldered for you. Some bays come
completely normaled or half-normaled without the option of changing any single
connection. On many models, each pair of jacks (front and back) are connected to
a removable PC card (circuitboard) which allows you to change the orientation of
the jacks for different configurations. In this case, a single colored jack
signifies the orientation of the PC card in its slot to make it normaled, half-normaled,
or denormaled. This usually requires taking the bay out of your rack and
unscrewing the metal cover to move the PC boards. Neutrik offers a 48 jack
patchbay for about $100 that has a removable front panel so you can change the
PC cards around without removing the patchbay from your rack. Pretty nice!
Another company called Re'an makes a 44 point patchbay that also has a cable
tester on it. Other companies include Carvin, AP, Fostex, DBX, Furman, Tascam
and Switchcraft. Just make sure that you study their specs to make sure you're
getting what you need. You may also need to buy multiple patchbays to give you
all the patchpoints you need to hook up your gear.
Patchbay cables, which are usually about a foot in length, are also easy to buy,
and are sold by companies such as Hosa, Re'an, and A.P. Audio. It is also
probable that you can buy patchbay cables from most of the same makers of the
patchbays themselves. Sometimes, the connections on the cables and jacks may get
a little grimy from dust and dirt, and in these cases, I recommend that you
insert the cables into the jacks several times to clear off the connections.
This works well, and is a better and cheaper alternative to buying cleaning
solvents.
One final note about patchbay models. Most of the bays I have described use
balanced 1/4" jacks. You can also buy patchbays that instead use balanced TT
jacks (tiny telephone), which are smaller and allow you to have many more
patchpoints on each row. While most commercial studios use them for this reason,
it may be expensive to buy the correct TT-to-1/4" cables to utilize this, so
consider the additional cost for cabling before buying one of these patchbays.
Setting up your Patchbay As I mentioned before, the way you set up your
patchbay is determined by the complexity of your studio, the gear you have, and
the frequency of patching you may need for each piece of equipment. Some gear
may never need patching at all. In that case, simply connect it up permanently,
avoiding the patchbay altogether. For example, one persons set-up might have a
stereo recorder permanently connected to a pair of subgroup jacks on their
mixer. You, on the other hand, might want to patch something between your stereo
recorder and the mixer, and in this case, it would be easier to use the patchbay.
Studying the way you work beforehand can make a big difference when the patchbay
arrives, and you begin hooking it up! Now here is a little dose of reality. You
may think that, for a hundred bucks, you can do all this stuff, and greatly ease
your signal routing woes. Not exactly. In addition to buying a patchbay, you
will need to also nearly double the number of cables you are now using, since
every unit now has to go to and from the patchbay. That can be expensive!
However, I personally feel that the added flexibility and convenience is well
worth the price. Besides, it looks pretty cool when you show your studio off to
friends!
As mentioned above, most patchbays have balanced jacks, and I have not seen one
that is unbalanced. I suggest that you use balanced cables to connect your gear
to the patchbay. (Don't let me confuse you though, because you can use
unbalanced cables. I just recommend balance cables because of their inherent
nature to reduce noise.)
I would start designing your setup by making a list of all your components, and
figure out which ones you want to have attached to the patchbay. Make sure you
have the correct number of cables to attach everything. Remember to plan out
which jacks you want to have normaled, half-normaled, and denormaled. This will
save you a lot of aggravation after you finish and figure out something is set
up wrong. I would also figure out which component jacks should be next to each
other in the patchbay itself, because some shorter cables cannot reach from one
end of the bay to the other. For example, you could position your aux sends and
returns relatively in the middle so it's within easy reach of all other points.
Ok, keeping in mind that all of these connections will be made on the back, one
convenient scenario is to have all of the following run through your patchbay:
1) All the outputs (or direct outs) of your mixer on the top row with the inputs
to the multitracks below it. Keep channel 1 of the mixer over track 1 of the
multitrack, and so on. Make this a half-normaled connection so they are
internaly connected. Again, it's pretty much standard to have outputs on the top
and inputs on the bottom.
2) All of the individual track outputs of your multitrack over the inputs to the
open input channels of your mixer. Again, keep track 1 of the multitrack over
the first input you plan to use for mixdowns on your mixer, and so on. Again, a
half-normaled connection.
3) The outputs of your aux masters over the inputs of signal processors that you
want to have permanently connected at the bay. This should probably be a half-normaled
patch so that if you ever want to send the signal from the aux master to another
processor, you can patch into the top jack on front and deadpatch the bottom
one. Then route the signal to your new processor.
4) The outputs of your signal processor (that we just talked about) over the
inputs to the aux returns on your mixer. I would make this a normaled patch to
leave it normally connected, but which would also break the internal connection
from top and bottom in back if you plug another processor output into the bottom
front jack.
5) Your mixer main outs over the two-track recorder inputs. Using a half-normaled
jack allows you to make two copies of a mix by inserting cables into the top
front jacks and running them to another recorder's inputs while still
maintaining the internal connections to your normal recorder.
As for hooking up dynamic processors like compressors and EQ units using your
insert jacks, you should use an insert cable (this is assuming that each of your
mixer channels has an insert jack). This may get a little tricky so let me first
explain insert cables. Insert cables are an unbalanced Y-type cable that has a
single 1/4" TRS plug on one end (TRS standing for Tip, Ring, Sleeve), and then
on the two arms you have separate 1/4" TS and RS connectors. On this cable, the
single end is both a send and receive plug, where the tip is the send (output)
and ring is the receive (input). On the Y side, the TS connector is now the
output from the mixer and the RS connector is the input back to the mixer.
Now, you could buy insert cables for each one of your channels, plugging the TRS
end into the unbalanced insert jack of the mixer, and the other two into the
patchbay. In this case I would put the insert outputs (tip) on top of the insert
inputs (ring). However, in order for this to work, the top jack must be normaled
to the bottom one. This is because the full signal path on that channel is now
diverted from the mixer into the insert cable, and must find it's way through
the patchbay back to the mixer in order for the signal to get to tape. If
nothing is patched into the front of those jacks on the patchbay, using a
normaled patch will allow the signal to flow through unobstructed. Also, if
there is a compressor hooked up to the front jacks, using a normaled jack won't
allow any uncompressed copies of the signal to go directly to the bottom jack in
back like a half-normaled jack would.
You can hook your compressor up to the patchbay using 1/4" TRS cables, one for
each input and output for each channel of the compressor. Make this a denormaled
connection since there is no signal going through the compressor when it's not
used.
This is a good basic setup. If you have any other dynamic processors, signal
processors, a sonic maximizer, or anything else, hook those up too if it meets
your needs. Just remember that you don't need to put everything in there; only
those units that you are used to patching differently, the way you normally work
with them.
In my patchbay, I have the following plugged in: Aux sends/returns, all
inputs/outputs of signal processors, the inputs/outputs of my DAT, cassette
deck, and CD burner, mixer RCA inputs / outputs (for listening to, and for re
cording to cassette tapes), a couple of sub-outputs from my mixer, and my
microphone preamp. Sometime soon, I plan on following my own advice, running all
my mixer inputs/outputs through my patchbay, as well as my 8 track inputs and
outputs.
Conclusion:
So as you can see, the possibilities and flexibility provided by a patchbay can
be a real lifesaver when dealing with a lot of gear. For about $250, you could
have a nice patchbay setup, and the ability to expand endlessly beyond that.
There are literally hundreds of ways to setup your patchbay, and as your studio
grows, you may have to redesign the configurations, but that is part of the fun
of having a nice studio. Believe me...once you incorporate a patchbay into your
setup, you won't want to work without it! Happy recording.
(c) 2000, Ken Lanyon,
All rights reserved.
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