Connecting it all together.

This part of my page connecting it all together is meant for the beginner or at least those of you who have not spent a lot of time connecting audio or processing boxes together in a series or what we call an audio chain. You may have seen pictures of all kinds of boxes in photos of other ham’s shacks and wondered just how you connect all those boxes so that it all works together.

There are several ways of doing the connection, but I am only going to tell you how I do the connections. I will also only describe the equipment I have chosen to use. The exact settings for the audio boxes I use can be found in other parts of this page, like the Behringer DEQ2496 for instance. So I will not tell you how to set it up here but please go to that part of the page to find out how. The equipment I am currently using from the microphone to the rig is as follows in order:

1.      Heil PR40 microphone with Electro-Voice 309A shock mount in a Heil Boom.

2.      Behringer Shark DSP 110 pre amp and processor.

3.      Behringer 1604A mixer.

4.      Behringer DEQ2496 Audio Processor.

5.      Behringer DSP1024 Effects Digital Processor.

6.      W2IHY I-Box

7.      Icom PRO III

I come out of the PR40 which has an XLR cable. A diagram of the cable and connector follows:

I use good quality cable. In my case I use Heil “Heilwire”. You can order it premade or in bulk from Heil.

I put all my equipment into an audio rack, which is a standard 19 inch wide rack. Mine was bought off of eBay and is an old phone company rack with only 2 rails and a top and bottom. I bolted the base to my floor and put all my audio equipment in the rack. It makes testing and modifying the order and equipment in a chain much easier.

After reading, re-reading, and reading again, the technical manuals for each box in the chain, the connection is really not that hard. If you can, use short XLR cables between each box. The cables should be as short as possible but still leaving enough extra to re-route the cable if necessary.

Keep all audio cables away or at least as far away as you can from power cables, control cables and for sure any coax cables. Put mix #31 split beads on each cable. The normal linkage goes to the LEFT input of the first box in the chain and then from the LEFT output of that box to the LEFT input of the next box and so forth to the end of the chain or collection of audio boxes you want to use. There seems to be a convention of using the LEFT side of audio boxes.  I don’t know why but most audio guys use the left side of the equipment. In some cases in advanced processing, both sides of a box may be used, but that is not part of this basic setup page.

Use only high quality audio patch cords XLR between components in the audio rack. If there are no XLR ports on your boxes, you may use TRS cables. Those are the standard patch cables you can get at most music or audio stores or online.  

The next box in line is the pre-amp. I use the Shark, but there are many good amps on the market. The Shark does many functions and is a small audio processor in itself. I use it as a mic preamp but one of the functions I like best about the box is that it gives you the ability to limit the amount of ambient noise that comes on your signal from equipment in your shack like the computer or amplifier and power supplies.

I come out of the Shark XLR to the mixer. Now you can do all the processing without a mixer. But a mixer will allow you much more flexibility than not having one. You can for instance put the audio chain in one channel, route audio to a computer for recording and play back, and have other channels for additional equipment like other microphones. I am not going to describe how to use a mixer as that information is available in a lot of other places on the internet. If you get one, just do something simple like putting a microphone in channel number 1 and taking the audio out of the mains out and to your rig. Play with just that until you get the path working and then go on to other audio boxes you may want to add to the chain.

Ok you have audio from the microphone to the pre amp to the mixer to each of the boxes. Left in to left out, one box to the other. So how do I get the XLR to my rig? That was the big question for me, for a long time. Do I go from the output of my last audio box to the mic input on my rig? There is not XLR mic input on most rigs so what should I do?

You can accomplish this task in a couple of ways. One way is to make up a cable that has an XLR on the end coming out of the last audio box and make up a cable like a mic cable that plugs into the mic input of rig. To tell you the truth I used alligator clips to hunt and peck until I got the audio to sound OK with no hum or anything. But there is a problem connecting to the mic input port on your rig and that is levels. If you come out of any audio box, they run at line level. The microphone port expects that there is a microphone connected and that device runs at microphone level output. Microphone level is at least 23db down from line level so unless you reduce the level using a pad or something your audio will be way over driven and you will sound just awful. I know I did. This is why you must use a device like the Murf-Box or I-Box. I talk about these devices in other parts of this page to bring the levels down. You can build a box or purchase a box form www.w2ihy.com

Most newer rigs allow you to connect via a DIN plug into the accesory ports in the back. In the case of Icom, it takes a line level device, so you can go right from the last box in your chain to the DIN input on the back. But I still use an I-Box to fine tune the level and to provide line isolation to keep AC hum and RFI down. I think it is money well spent. If you are going to use a I-Box or like device you will come out of the last box in your chain XLR. Get a cable from any music or audio shop that has a TRS connection on the other end. You will plug that connection into the input of the I-Box. From the I-Box you will go into the rear input of your rig. If you are lazy like me, contact W2IHY and ask him to build you the cable that comes out of the I-Box to the DIN input on the rig you have. He can build one for just about any rig on the market. While you are doing that have him patch out the fixed audio of the DIN plug on the back of the rig so that you can use it for recording and play back.

I found the manuals that came with the components that I bought, made little sense until I started to set the units up myself. You are trying to produce a sound that you like. Not a sound that fits the taste of some big gun on the bands who thinks he knows all about audio. This goes for the guys on 14.178 as well. You are trying to make a sound that best describes you and what you like. Of course, things like hum, or lack of any highs, lows or muddy sounds will detract from your audio. Once these problems are fixed, you can go on to develop a sound you like that you feel fits you. I bet you can't stop fiddling with it though. Seems to be a common malady among audiophiles.  Having said that, do take as constructive criticism the comments of other audiophiles on the bands. Many of them can record you and play it back so you have an idea as to what you sound like. This can sometimes be a little misleading  because of things like band conditions, phasing, QRM, and the strength of the signal at both the recording and receiving station.  These facts may give you a false evaluation benchmark, but is still worth the effort. It has been said by many of the guys who have been messing around in audio for long time that more equipment has been bought and sold because of recording than any other factor. I believe that to be a true statement. Never make a major change to your system or audio, based on just one recording or critique by one ham.  However, that being said, most of the guys who can record and play back your audio, try very hard to give you an accurate  recording and playback.

 There are other products you can use to evaluate your sound. There are several PC spectrum analyzers available that use the audio from you transceiver and plug it into the line/mic input on your sound card. This method gives a pictorial representation of what your signal looks like. You can print the graphs and store them to see how much progress you are making and how your audio signal has changed. There are 3 packages I use,  SpectraPlus , Spectrum Analyzer by PAS software and the newest one HamAlyzer. All do a good job in my opinion, but one is quite a bit more accurate but expensive. I prefer HamAlyzer because it was written for hams and even with some limitations, it is the best bang for the buck, in my opinion.

I gave you this information because it is important when doing the programming and tuning of the components. Some of my tuning is done while looking at the spectrum analyzer software. You can also make recordings of your signal if you have your system set up correctly especially if you have a mixer. You can also rely on other audiophile hams who can assist you by doing a graph and sending it to your or make suggestions on the air after looking at the graph. 

When making your connections between audio devices keep good records. If you find that real great sound and then suddenly lose the EQ, if you do not have it written down you may lose a lot of time in recreating it. Also it is a great idea to make, and file away so you can find it, a good block diagram showing where the connections are made. That is how the cabling is done and what the order of the devices is in relation to each other. I have made changes over time in my rack and a good picture of what it looks like on paper has saved me a lot of grief. Keep a log of the date you make changes so that if something goes wrong down the line, you can look for the obvious change that may have caused the problem. 

Of course it should go without question that you keep all manuals and documentation on your audio rack. Also keep a copy of the sales receipt in each manual so you can recall when you purchased if and from whom, in case you want to get another device like it or get repairs on the one you have.