Wednesday, October 16, 2013

Hexaphonic Guitar System: 3

I got the adapters I needed yesterday, so I was able to get everything connected solidly. These little puppies are very useful, and I didn't even know they existed until I started poking around on eBay. What they do is, they take an insert jack - which is usually used as a loop to insert compressors or effects units, hence the name - and they make them into direct outputs. Evidently, live sound engineers use them a lot to get direct outputs from their boards for live multi-track recording. The RMC Fanout Box has an insert jack for each string, so if you want to use them as outputs, as I do, you need these adapters. Otherwise, a regular mono TS guitar cable won't make proper contacts.

I expected them to be from some exotic manufacturer, but no, they are made by Hosa. I got eight so I'd have these extras. For those interested, it is called a DOC-106 INSERT DIRECT-OUT ADAPTOR. They must be fairly common if Hosa makes them.

Here's one unboxed. As you can see, it has a male stereo TRS jack on the right, and a mono female TS jack on the left. The male TRS makes all of the proper contacts, and the female TS accepts any old guitar cable. The female return jack was just left out of the wiring. Very cool.


I set all of the units up to provide distortion for every string, and it really doesn't sound like six different guitars, and complex harmonies still sound mushy, just not as mushy as with a mono or stereo system (There is some crosstalk between the strings). Mixed into the background of the clean stereo guitar sound, though, it's very spooky. I'm going to need the winter to mess around with it, but one thing I know for sure, and that is that the solid state preamp in the Lexicon MPX-G2 does not have a sweet enough overdrive sound. I knew this would be the case, as I've been spoilt by over thirty years of MESA/Boogie tube amps. But since I've proved the concept with the Lexicons now, I'm going to build another hexaphonic system with six MESA/Boogie preamps. Since the ones I want are discontinued, it will probably be a while before I can scare up six of them. In any case, this has been a marvelous project and I'm learning a ton from it.

Now that I have all of the elements sorted out for my main recording studio, I'll be able to turn my attention to the Synclavier and the Fuga Electronica album. In my down time from working on that, I'll explore the hexaphonic possibilities. First, though, I'm going for a week's vacation out west in the Ferrari! I haven't been away from my house in over three years, so I'm hitting a wall with my motivation and I badly need a break.

Thursday, October 10, 2013

Hexaphonic Guitar System: 2

This morning, I got up and finished the connections for the hex system.

First thing was getting the RMC Fanout Box connected to the six MPX-G2's. Note that I found some red felt that matches the Synclavier keyboard. No scratches!

One nice feature of the MPX-G2, is that it has guitar inputs on the front, and on the back. I used 6' guitar cables so I'd have enough slack to service the system without unplugging everything.

Next step was to connect the guitar to the Fanout Box, and the Fanout Box to the Axon AX-100. The cable on the right is from the guitar, and the cable on the left is to the Axon.

Unfortunately, the 13-pin Roland-compatible guitar synth cables do not come in specialty lengths. The shortest I've ever seen is 15 feet, so I had to use a cable saver to make it manageable.


Sorting things out quickly became a harrowing experience. The six outputs on the Fanout Box double as inserts, so the guitar cables had to be about 2/3 of the way in to make proper contact, and it was very fiddly to get all six working. Took a long time. Then, once that was done, I discovered that unit #4 had a blown output transformer. Arg! So, I had to cannibalize my secondary recording rack for another MPX-G2 (I have nine total now!). I sort of/kind of expected this, as these units are vintage rack gear at this point.

Due to all of this morning's frustrations, I decided to knock off for the day when I tried the Axon and it was horribly noisy. I'm sure that's due to the improvised guitar connections, so I got on eBay and searched for insert cables. Well, what do you know, but there is an insert to direct output adapter cable! It has the regular stereo male 1/4" connector to a 1/4" female TS connector. Needless to say, I scooped up eight of them so I'd have spares.

So, I'm on ice again until those adapters get here.

Wednesday, October 09, 2013

Hexaphonic Guitar System: 1

I finally found a sixth Lexicon MPX-G2, so I was able to complete my hexaphonic guitar system!

Back around 1977, I read an article in Guitar Player magazine about, "hex fuzz." The amazing advantage to hexaphonic distortion is that you can play complex harmonies without them turning into dissonant mush. It sounds like several guitars playing in harmony instead of just one. The problem back then was that the solid state overdrive circuits were primitive, and so they sounded very cheesy. The idea stuck with me, however, and when MPX-G2's started coming down in price, I realized that with six of them and the RMC Breakout Box, I could finally make a high quality hexaphonic system. I started collecting them about four years ago, and it's taken me this long to find six nice units. This post will be about how I put the system together.

To do it right, you need a lot of cables of the correct length.

I needed seven foot long and two foot A/C cords, twelve two foot patch cables, ten 6' guitar cables, and six 1' MIDI patch cables.

Then, of course, a half-dozen MPX-G2's. The original list price for these was $2,400.00, so that's $14,400.00 worth of Lexicons at the original price!

I put the units in an 8U SKB rack with a Furman AR-1215 power conditioner on the bottom, and an Ashly LX308B stereo mixer on top. The Ashly is very cool, because it has 8 channels, each of which has left and right inputs.

The first step is to install the A/C cables. Everything goes down the left to the bottom of the rack, so they will be away from the patch cables: Less chance for noise.

Then the MIDI patch cables. Every THRU goes to the next unit's IN. That way, a single MPX-R1 remote can change programs on all of them at the same time!

And now, the 12 audio cables. See how nice and neat this is? The audio cables are away from the A/C cables, so it will be nice and quiet.

Here's the entire system, powered up. The next step was to dump all of the programs from the stereo unit on the top to the hexaphonic units below. I got my first MPX-G2 in 1999, so I've been tweaking those programs for almost 15 years now!

Ta da! The dump from unit one to units two through seven went off without a hitch. Now all of the Lexicons have the same programs in them.

Tomorrow, I'll connect the hex rack to the Lexicon FW810s FireWire recording interface, and the Breakout box, and I'll be able to start modifying the programs to add distortion. That's done in the preamp section, so this could take a while.