MCI JH-636 Story


analog for the people!
Hey, Sweetbeats can't hog up ALL the MCI insanity around here, eh? :D ;) ;)

Forgive the ensuing typos and grammar, I will go in for some editing later!

So this requires some backtracking because I actually bought this console at the end of February, and received it at the tail end of March. I started installing it the day it came in, and have been working on getting this puppy in action ever since. As we've seen in other "Story posts," these things do tend to snowball....

As the story goes, a fellow from the Dallas area posted on another forum that he knew a guy with a pretty clean MCI 636 console that could probably be gotten for a good price. It seems the seller had this in his home studio (that is to say, the house was the studio and he lived in it), but he was in well over his head and needed to get the console out. Unfortunately, do I put this delicately...was utterly lacking in the most basic tenets of salesmanship and couldn't answer the most basic questions about its condition. Fortunately, the fellow who had hipped me to the console was willing to go check out the console for me and report back. He wound up doing this several times.

After some back and forth, I had ascertained that this 636 was shortloaded to 28 channels, that one of those channels was missing some parts and needed to be rebuilt, and that about 7 more channels weren't passing signal and had some lights out. This console had the optional phase meter which I pleased to learn because it's something I've found myself wishing for for a while now. The console, like all 600s, had a very nice, flexible full TT patch bay built in, and it also had an optional tie-line patch bay which would be very necessary because large format consoles with built-in patch bays don't have your typical XLR and TRS jacks on the back like smaller format mixers. They have multi-pin connectors and the idea is you wire your entire studio to the console: recorders, rack gear, studio lines, the whole enchilada. My studio is a co-op space meaning I had a studio, a buddy had a studio, and we combined our gear into a big studio with lots of gear all of which would need to be hard wired to the console! It was going to be a big-boy install job! Up until now, we'd been using a battery of 9, count 'em 9 DBX 1/4" TRS 48-point patch bays, and frankly, they really hadn't been up to the task these days, they weren't quite commercial quality and in the last year I'd found myself correcting many cracked solder joints in the TRS modules to get signal flowing through them properly, so the idea of a solid, commercial grade TT patch bay really did appeal to us despite the big job it was going to require.

The console's channels were mostly standard 3-band semi-parametric EQ channels, but a couple had the nice VariQ parametric EQ options, and since it was shortloaded, I could fill it up with some more VariQ channels from parted out consoles as they became available and funds allowed, so I looked at this is being a better situation than if it had been fully loaded with standard EQ channels. I also learned that this one was a JH-636-VU-AF, meaning it had standard mechanical VU meters rather than the plasma meters that were and expensive option back in their day, but are nothing but problems these days. I also think the VUs look much better and I prefer their ballistics. It also had a box of spare odds and ends--an extra phase meter card and four spare fader packs, which made me happy because it meant I could add in four more channel modules later without needing to source matching fader packs.

The "AF" meant Auto Faders. Oh yes, late 70's VCA automation at its fin...auh, worst, actually :D The MCI JH-50 was as far as I know the first commercially available console automation system and, as tends to be the case with these things, they didn't quite nail it on the first try. Instead of later systems which used either an on-board or outboard computer to crunch data and store on hard or floppy discs, this early version used digitizer boards in the console's belly which sent data through patch points on the patch bay to TAPE! Yes, the idea was to send the data to a couple tracks of your 24-track machine for storage, egads! It was also almost certain that the auto system wasn't performing correctly because frankly most people haven't bothered with that auto system in years. However, on the "AF" MCI 600s, the automation system not only controls fader positions and channel mutes, but also solo-in-place and the grouping, so even if I didn't aim to automate mixes with it, it still needed to work. I figured I could probably get the auto system back up with a re-cap and maybe some cleaning or at worst a couple chip replacements, and in the meantime, the console would be functional enough with the auto system switched off as there are still hard channel mutes and the faders on this model would thankfully still work with the auto off.

I also ascertained that this console had the "dreaded red" IC sockets which are notorious in MCI gear of the mid-70s through early 80s for being fairly not-great quality. Now, I've been regaled by tales of ICs having badly oxidized contacts or even falling right out of the sockets due to poor contact. This said, MCI fans are polarized on the "dreaded red" socket issue. Some say they're all garbage and to plan on removing them ALL and putting new, quality machined sockets in. Others say that only some will be a problem and to just replace as necessary. I decided that I would subscribe to the latter.

I further learned that other than some scraped up woodwork, the console was relatively clean inside and out for its age, that it wasn't caked with grime, missing paint, covered in a film of tobacco stank and so-on, but would need some re-furbing. It had other typical issues such as most of the VU lamps being burnt out (when it finally came in I counted 7 out of 68 lamps working). I knew this console, like any console of this age, would need a good cleaning as far as pots, faders and switches were concerned, no surprises there either.

I also learned that it hadn't ever been re-capped, which was a good point of leverage on the price as I would be going waaay out on a limb to buy this sucker and wanted to get it as cheaply as possible. Re-capping a console like this is a BIG, tedious job, but not one that has to break the bank if DIY'd. I also knew that I would NOT be likely to find a fully re-capped 600, and if I did it would cost a mint to buy, so I made peace pretty quickly with this point and decided I'd rather be the one to re-cap it if it had to be done, as I could spec out my own preference for caps and have control over the job.

Knowing that the seller had ZERO tech skills and most likely had never put the slightest bit of maintenance into it, I felt that the derelict channels were most likely caused by some combination of cooked caps and funky ICs or sockets and that I could probably have them passing signal pretty easily, so made peace with those issues and again used it as leverage on the final price.

I had decided what the console was worth to me and and made the offer. The seller was going through personal problems and had become somewhat emotional about things. He rejected my first offer despite his desperation and I realized that the fellow who had been answering my questions and doing the legwork was better at talking to him. I arranged to have him act as a broker, get my offer accepted, then secure the console for me and hold it in his garage until I arranged to get the console out of there. Eventually after a couple weeks of patience and cajoling, the seller accepted an offer and I wound up paying what it was realistically worth given the condition, which was about half of what he'd been asking.

In the meantime, I had been working out how I would get this beastie the 1,100 miles from Dallas, Texas to Oshkosh, Wisconsin. I estimated the combined weight of the console and PSUs to be around 700lbs and quickly learned that any kind of freighting really was going to break the bank. Rut-roh! It was going to have to be picked up... "OK, who do I know with a big vehicle? Aha, my stepfather has a Suburban!" I worked on getting some measurements of the console, the PSUs and the load area of the Suburban. I really thought it would be a close one. As it turned out, the console was a little over 7' long (sweeet :D ) and about 41-42" deep. My stepfather smugly informed me that he could fit a sheet of 4' x 8' plywood in the back of the Suburban no problem...phew! It would all fit. The console would need to be transported with the modules removed and boxed up, because moving a console frame of this size and weight will cause it flex. This could damage the module boards and I really didn't want to deal with broken card ends. Fortunately, the broker could have the modules removed, boxed up and ready and it would all fit. All I had to do was figure out if my stepfather was up for a road trip to Dallas, and work out how long the trip would take and how much gas it would gobble up--less than the cost of freighting, that's for sure! :p

Well, by now it was early March and the Wisconsin winter had been a real dickens. I called my folks up to talk turkey about the transit right around the time we'd gotten yet another late-season blizzard and, wouldn't you know it, a trip to warm Texas sounded pretty good to them! :p They had been thinking about taking a short vacation somewhere to get away from the winter (and work) woes, and since they dig a good road trip, decided that at the end of the month they would drive down to Texas and hang around the Dallas area for a few days, get a little relaxing in, enjoy the weather, see a few sights and then pick up the console for me on the way out :eek: At this point, I would like to say that my folks really are fantastic people! :p :p

This is actually a good tip for anyone here who's thinking about buying a large piece of gear from a distance but isn't sure how to get it home. Maybe you know someone who wants an excuse to take a road trip, eh? :D

Well, I spent the rest of March anxiously waiting while researching preparing what I would need to get the console installed and refurbished. I had the broker mail the manual up to me ahead of time so I could look through it, get familiar with the console's functionality, look at schematics and figure out what how signal flowed through the console and get an idea of what I'd be in for re-capping-wise. I also needed the wiring diagrams so I could get a head start in the installation process.

Consoles with patch bays use multi-pin connectors that you hard-wire your studio to. Some use D-Subs, others use EDACs, while some, including MCI 600 series, use a 30-pin connector called a Tuchel.

This is what Tuchels look like; note the one with the housing off so you can see how the audio cables are wired to them. In this case, the previous installer had used black and red heatshrink to denote inputs and outputs:


These are the Tuchels I'd bought ahead of time. They'd had a bolt cutter taken to the looms during the previous owner's uninstall as is typical, and I had to de-solder the old bits of cable left on them. What a PITA, but used Tuchels are much cheaper than buying news ones! This was the first of several ways I wound up trading tedium for value.

In the case of this console, only 24 of the 30 pins carry signal; there are columns of three pins that respectively carry the high signal, low signal, and shield of each balanced audio line, and they're in rows of 10, with only 8 actually being used on MCIs for some reason. You wire it up from bottom to top with a 4 channel in-out configuration, that is, from bottom to top, channel "1" out, channel "2" out, channel "1" in, channel "2" in, channel "3" out, channel "4" out, channel "3" in, Channel "4" in. This was all kinds of confusing at first, but as I started to write my wiring diagram for the studio it became second nature pretty quickly. Did I mention our studio has lots of stuff to wire in? With each Tuchel connector carrying only 4 channels of inputs and outputs (and a couple only carrying 2 i/os due to 36x2-pt the patch bay configurations), I figured that we would more than fill up every multitrack and tieline point on the patch bay, would need 28 Tuchels to do this, and that the console was only coming with 15 of them. Fortunately I was able to source more Tuchels before the console came in, and decided to get the multitracks and studio monitors wired up by the time the console came in so that I could plug the Tuchels in and start testing its functionality right away. My wiring plan ended up 9 pages long in the end, and that's only because I ran out of patch points to fill :D

I also needed to figure out how to wire things in as cheaply as possible--this meant recycling as much of our old cabling as possible. Some weren't long enough to reach the console, so I was tasked with figuring out what gear would need to have new cable looms made. Some were on pre-made line snakes, some I had re-wired for a previous patch bay re-config with custom Belden 8451 looms, and in some cases I found that the gear further away from the console could have its looms harvested, re-terminated as necessary, and re-used for closer gear while the further racks would get new longer looms made. My studiomate bought 1,000' of Gepco install cable for any new looms I would need to build and we get them as 500' of red jacket for inputs, 500' of black jackets for outputs so the color coding was a nice touch. Also, since we were going from a 1/4" TRS patch bay to hard wired, it meant that I would be clipping off hundreds of TRS jacks from the looms and would have plenty of TRS jacks (mostly Neutrik) to recycle for any rack gear that needed them with new or re-built cable looms. This would add more time on the install job because lots of parts would need to be de-soldered before being re-soldered, but I had worked up an efficiency plan so that in the end, the studio would only see about 3 days of full-on downtime (!!) during the install anyway, especially since I was getting a head start on the job and snagging off-days leading up to the console's arrival, so I was able to fudge in more install time without much inconvenience the the studio's operation while saving a mint too!. As you can see, our tight budget made this install extra-extra-complicated! I'll tell you, I learned A LOT about keeping costs to a minimum while still doing a decent quality job of it, and I learned a lot about how to keep the studio going as much as possible eve during HUGE transitions. This console was making me a more professional engineer even before it arrived, and as you see, I kept plenty busy while I waited for for it.

Well, finally the console arrived at the end of march with the broker and my folks all confirming that the console was PLENTY heavy even with all the modules removed and that I'd better have some guys on my end ready to help unload and schlep it into the studio. In the end it took 5 of us to get it pulled from the Suburban, flipped onto its back on some furniture dollies, finessed into the studio through three doorways and into the control room. We bolted the legs on, got it upright, and I'll tell you the sight of this behemoth in the room, standing up in its new surroundings even with with no modules, really made us forget about the dull back pain. I can't imagine having less than 5 people schlepping! "They don't make 'em like they used to!" Heavy steel and solid oak, I love you but you're freakin' heavy! :D

That night I inventoried what came in and took stock of any visual problems I spotted. As I put modules into the console, I inspected them, and, hey wouldn't you know it, I found 7 modules that either had ICs missing or damaged. Yep, it looked like my hunch on the 7 derelict channels probably being an easy fix was right. One selling point on this console is that it has lots of parts that are not only available off the shelf from places like Mouser and Digikey, but also in common with our MCI JH-110 8-track tape machine. The missing ICs in the modules were MCI 2003, also known as common NE5534s which I had a stash of in the tape machine parts bin. I put those in some of the missing spots, and found that that 28th channel that needed some rebuilding was actually missing several knobs, switch caps and the mic preamp. I decided to keep it out as a spares, buy another channel off eBay later and only load 27 channels to start. I harvested the rest of the ICs I needed from it and had 27 channels loaded up with all the necessary parts to start testing it out.

When I had everything in the console, I snapped these pics and called it a night....




It always bugs me that people never show the backs of big consoles like this. I was really curious to see the anatomy of rear panel of this console especially with the unfamiliar multi-pin connection scheme and it drove me nuts that I couldn't find a photo of it on them, for the curious, here's what an MCI's rear panel looks like with nothing except the power supply harnesses hooked up to it:

OK, there's more to the story but enough typing for now, I have to get back to re-capping modules (ah but now I'm getting ahead of myself on the story, hehe!)

(to be continued...)
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Good gracious...makes me itch to work on my 416.

Your Suburban transport made me chuckle as I've used mine to haul a number of large items and yes indeed it does fit a 4' x 8' sheet of plywood. My 416 is just about 42" deep also and was a nearly snug fit.

I'm working out what to do about my studio connections...the 416's had punch blocks on the back for studio connections but I'm reading that the ones they used were really designed for solid wire, not stranded and therefore aren't the most reliable.

Keep it coming,'re WAYYYYYYY ahead of me.
This is going to be a great one! I can't wait for more! Perhaps for posterity you can shoot detailed images of channel strip sections and the master section. Such a cool looking board! Nice find and good luck on the refurb :)
Oh boy have I got some catching up to do!

sr71rules, good timing, you're right where I left off!

Well, the day after the console had come in and I'd gotten the modules in, it was time to get to know my new pal.

The first thing to say about this console is that it was immediately clear that it's positively oozing with personality, as items of this nature sometimes tend to do. I'm not really a sentimental, name everything sort of fellow, but when I sat down at it, I felt that I was about to go on a journey with it, was about to develop a rapport with it, was about to spend quite a bit of time shining flashlights up its ass and in its short, it became immediately clear to me that this console has character and IS a character and that his name was Alan...and like all MCI consoles, he has a beard. MCI is burly bearded flannel shirted gear. It's Richard Karn in recording equipment form.

Ah, but don't take my word for it.

MCI 636:

Richard Karn


Richard Karn

MCI 428:

Richard Karn

MCI 536:


Are we seeing any similarities here? :p

OK, now that you all understand I'm insane, let's meet Alan The Bearded MCI as I did on day numero dos :cool:

This is MCI JH-636-VU-AF, serial number 0193, an inline, 24 buss monstrosity. The frame is dated Feb. 6, 1980 (making it almost a year and a half older than I am,, hehe :D). I haven?t yet found any record of who originally sold and purchased this console as new, but this one is relatively early in the 600 series production run. It would have cost somewhere in the neighborhood of $55-60k as new in 1980.

The first thing I like to do with consoles is oogle the channel strips.

Something to know about MCI 600s is that there were a few different module revisions made over its production run and, along with a bunch of other, less common options, there were two main types of EQs. Earlier board revisions were numbered 0136 while later versions had 4030 boards. There are subtle differences between the two. In addition, on either board version there were standard 3-band semi-parametric EQs as well as optional 3-bands with variable Qs, which are a nice improvement over the standard EQs. My console 22 channels of the older type 0136 boards all with the standard EQs, one of which I?m using as a spare parts module. It also 6 of the newer 4030 boards, two of which have the VariQ EQ option. These must have been added later for whatever reasons.

Again, I apologize for the crappy pic quality. I reaaaallly wish I could afford a nice new Nikon but we?ll have to stick with the ancient hunk of junk for now!

MCIs have somewhat unique routing which bears explaining, so let?s take a tour!

Here are a few of the standard EQ modules. These particular three are 4030 versions.


Let?s start our closer look at the top with the Mic/Line in and buss assign sections.


The Mic input has your typical gain trim pot, plus there?s a ?gain? switch which adds more gain. With the Gain switch out, the pot trims from 12db to 35db of gain, which is suitable for hot output mics such as condensers or dynamic mics on loud sources. The Gain switch bumps that range up to 30db-65db of gain for ribbon mics or moving coil mics on quiet sources. There?s also a switch for phatom power. The Line switch takes the mic pre out of the circuit and selects the line input instead, which is what you want for mixing or for tracking through the module while using an outboard mic pre. Unusually, the line input gain structure is not set with the typical roatry pot, but with a toggle switch that selects between 0db at +4dBu reference, or + or ? 6dB. I?m quickly learning to like that limitation as it gives me reason to set my gain staging into the recorder well, and curtails the likelihood of setting up shoddy gain staging for remix.

To the right of all this are the buss output assignments; their output trims are seen under the line/mix stuff. At ?cal? is a unity output reference, and there?s a 6db trim outside of ?cal.? There?s a toggle switch to quickly and easily ?ping pong? the channel outputs to the even or odd (left or right) side of each stereo buss. The center position is ?PAN? which, instead of a hard left/right output, lets you use the above pan pot to sweep the output anywhere ?in between? which is a nice touch for submixing during tracking. At the bottom of the row of numbered buss assignments is a "Direct" switch which disconnects the channel output from any of the 24 busses and routs its output to its input, making it a 2mix or floating channel.

At the bottom of the section are a white solo switch marked with the channel number, and a ?DUMP? switch whose main job is amuse clients who point at it and say ?look, you can take a dump on this consle! :p ? but also selects a special routing option in which the Monitor 2mix output is sent to whatever buss output you have assigned. Don?t worry, I?m still trying to wrap my head around that one too.

Now let?s move down to the standard EQ section:


The middle frequency is a semi-paramtric type with a broad sweep at a fixed Q which, like most fixed midrange Qs I?ve had my paws on, is slightly wide for my taste. The high and low frequencies are shelving type EQs which would normally seem limited, but their shelves are sweepable in a broad range as you can see. You can further use the high and low pass filters in conjunction with the swept high and low shelves to make it function rather like a poor man?s semi-parametric with a sort of semi-variable Q. The high and low pass filters, by the way, are outside the switched EQ circuit meaning you can use them even when the EQ section is bypassed?another nice touch. The high pass is set at an unusually low 45hz, while the low pass filters frequencies above 16khz which is fine by me, though I might have preferred it at 18khz. I may looking into modding those freqs as well as maaaybe narrowing the stantard EQ?s middle Qs, we?ll see if that pans out. At the bottom of the section are the phase flip switch which is also unaffected by the EQ bypass, and a Channel button which switches the EQ between line and monitor sections.

Here, by contrast, are the two VariQ versions:


These are laid out much like the standard EQs, but the middle Q is variable between .3 and 3. This really opens up the usefulness of the middle EQ as you can get quite narrow and fix problems, or go quite wide for some sonic sculpting as you see fit. In addition, the high and low frequencies can be switched between shelving or peaking type; for when peaking is selected, there?s a Q button that subtly changes the peaking Q by about one and quarter decibels per octave. The sum total of these extra features is a much more flexible EQ section and I will definitely be adding more of these channels when funds allow.

Now we move down the auxiliary sends:


Sends 1 and 2 are independent, monaural sends. They?re switchable pre or post fader and the Wet switch routes them into the output busses in case you want to track a source with effects.

Sends 3 and 4 are a stereo send which can be panned between 3/left and 4/right, so you can use them as non-simultaneous dual monos or as stereo sends, great for a headphone mix.

Sends 5 and 6 are the same idea as 3 and 4, they can be a second stereo headphone mix or whatever else your creativity leads you to, plus they can be switched to route right into the 2mix, meaning that during tracking through the console, you can use the 2mix is a general headphone cue and set up Sends 5 and 6 as ?more me? direct injects into the 2mix, yet another nice touch that, on simpler tracking projects, will make our Oz Audio Qmix headphone cue system?s direct injects slightly redundant. In conjuction with the flexibility of the aux returns on the master section (which you?ll see in my next post), I?ll say I?m looking forward to setting up headphone mixes on this bad boy!

Now we move down to the bottom of the modules with the monitor seciont. This is where the 0136 and 4030 board version show their differences. The module on the left is an older 0136 version while the two to the right are the 4030 revision:


At the top is a hard mute switch that mutes the channel output to the 2mix buss. Next to that is the white Monitor section solo, marked with the channel number. Unlike some other inline consoles (such as the Tascam M3500/3700s) which use small, short-throw faders for the tape monitors, the MCI 600 series use rotary level pots as you can see. Above that is the channel pan pot. The Rev switch, which changes its place from top to bottom on the different board versions, is a routing feature which switches the tape monitor input source between the Line input and the Buss output. The VCA switch, which also changes its place from top to bottom on the two versions, switches the fader VCA automation between the channel slidewire fader and the rotary monitor ?LVL? fader. This is interesting because the main fader is always a non-bypassable VCA fader, while the rotary monitor fader doesn?t have to be. At the bottom of the section is the Pro-Fader Listen switch which of course lets you hear the channel?s pre-fader output through the studio monitors without disturbing the buss output.

You?ll also notice that the 4030 channel revision add and extra switch called ?BUS.? It routes the monitor fader?s output into the channel fader as a sort of stupid pet trick to sneak an extra line source into a single channel?s output. This would become more common on later inline consoles.

Hoookay, that?s plenty to digest for now. In the next installments we?ll meet the fader packs, master section and power supplies (yeah, plural! hehe), then delve into giving Alan a preliminary cleaning and see how grouchy his condition was when he showed up?then eventually we?ll delve into what would become a full re-cap project that I?m already well into in real life?still playing catch-up on the story! ;)

Hasta next time?.
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Wow! Lots of detail and the shots look great! Thanks for putting in the effort on this thread. Looking forward to more :)
OK, sorry for the delay--been busy working on the console, doing studio work and putting in my vegetable garden at home!

Let's have a look at the master section:


It's comprised of three modules: the COMM module on the left; Master in the middle and the Monitor modules on the right. Although individual modules, they do share some common functionality--which I found out the hard way after failing to get the console to power up properly its first two days in the studio! As eagle-eyed viewers may have spotted in a couple photos above, it turns out I'd had the COMM and master modules in each others' slots and Alan wasn't one bit happy about that :D I love gear that knocks me down a peg or two, hehe! What can I say, the manual says many things but not which thinger goes whaaar :P

So...starting on the right, the Monitor module controls the console's output switching to either of two sets of monitors: the control room monitors, or Studio monitors which would be monitors mounted in a tracking room so the talent can either monitor a cue while they track, or so the engineer or other personnel in the control room can talkback to people in the tracking room through the speaker rather than through headphones. Although we do have some monitors mounted in the tracking room, I do not have them wired to the console because we actually have a bunch of sets of monitors between the control room and tracking room, so we already use an external monitor matrix for all that. In my case, the MCI's Control Room monitors are wired to that external monitor matrix, kind of a faff, but we have more monitors than the MCI can handle on its own!

OK, starting at the top of the module is a fairly useless (because my channels don't have the option) Broadcast switch which is intended as a special input routing for console installed in broadcast facilities.

The next two white buttons below that are global switches which place all channels in either Line or Tape monitoring mode. The channels each have their own individual Rev switches for this as discussed above, but it's quite nice to have these two global switches for easily flipping the console between tracking and remix modes.

Below those, we have two rows of schadow switches with the black caps. These switch the monitor source, and there are a bunch to choose from: you can monitor off the any of four "Tape" sources, which are intended to be 2-track decks. Tape 1 is for a mono deck, while the other three are for stereo decks. I only have one 2-track source actually wired up right now and it's my HHB CD recorder on Tape 2. When I get an analog 2-track mixdown deck, I'll wire that up to Tape 3. After the four Tape sources, there are switches to monitor off sends 3-4 and 5-6, nice for checking headphone cues without getting up and going to the studio to check peoples' headphones! Next is the Mono buss monitor. Below that is the 2mix monitor (or stereo master buss monitor, if you prefer). Finally, there's an Aux source. This works in conjunction with the Aux patch points on the patch bay...we'll get into that in the next installment, but basically you can patch a couple channels of "whatever" into the patch bay and be able to monitor it. Last thing to note about these monitor sources switches is that you'll notice there's two rows of them. The left row feeds the Control Room monitors, while the right row feeds the Studio Monitors (unused in my case).

Below the source switches is a rotary pot which is a trim for the PFL/solo buss.

Next down in a Mono switch for checking mono compatibility on any of the stereo sources.

Below that is the Alt Speaker switch which is fora second pair of Control Room monitors (traditionally a big pair of soffit mounted mains and a pair of nearfields on the meter bridge, though in our shop, we have two sets of near/midfields, and a third set of monitors for the control room couch and we switch between all this externally).

Below that are hard mute switches for the control room monitors, one for Left and one for Right.

The yellow button is a Dim switch for temporarily attenuating the monitors, say if you want to quiet 'em down for a sec to make a comment to the person sitting next to you. The green switch mutes the Studio monitors, so not useful in my case.

Now let's have a look at the Master module in the middle. This fellow handles the outputs for the Aux sends as well as their returns, which are nice as they free up channels if you don't need EQ on your returns, and they add some routing pet tricks.


At the top are yellow rotary level pots controlling the master output levels for Sends 1 and 2 which are mono.

Next are the blue pot and red pot for stereo Sends 3-4 and 5-6 respectively. Each also has a black 2mix button for injecting them into the 2mix buss, a nice touch especially for "more me" headphone cues!

Then we have four Send Returns, each with a rotary fader pot, pan pot, a black Mute switch and a white Solo switch. Returns 3 and 4 also have a white capped "Spin" pot which is a pet trick that controls the level output to the return patch point on the patch bay.

Overflowing onto the top of the COMM module on the left is the Return for Sends 5-6. It has enhanced routing capabilities compared to the first four sends in that its output can be routed to any of the 24 channel busses using the row of switches in the picture in conjunction with the Odd/Even "ping pong" toggles switch or the buss pan pot which is the red capped knob at the top. This is all familiar stuff from our discussion of the channel modules! Then there are the usual black Mute and white Solo switches. Below that is another red capped pot for the Send 5-6 output level, then a big black rotary fader for the Return output. All very clever (and a bit confusing lol!)

Now we move down to the next section which is the Oscillator. These are all the black buttons with the black knob in the middle. I have to say I'm quickly getting spoiled with this very nice oscillator section! The first three black buttons in the section are the frequency multipliers (1x, 10x, 100x) and the knob selects frequencies to be multiplied. Basically, you can select any frequency that's a multiple of 10 between 20hz and 20khz. Schweet! There are also buttons that switch you from sine tones into noise generators--white noise or pink noise. Double schweet! :D The two buttons below the frequency knob are for sending the oscillator globally to either the channel busses (labelled "TKS") or just to the 2mix buss. In addition, the oscillator also has a dual-purpose patch point on the patch bay that lets you either patch it into a piece of external equipment for testing, or for direct injecting the oscillator into another patch point. This is very useful for testing purposes--for example, if I have a problem with a channel module and want to use a test tone to see where the signal isn't getting through, I can inject the oscillator into the mic preamp, or into the EQ section, out of the EQ section or direct into a channel fader. This has been a godsend as I test out my channels! I'd never thought much about console oscillators before but having this full-featured one is a boon. Whoda thunk it could bring my nerdy ass so much joy :p :D

Below the oscillator are some trimmer pots for the various talkback and slate output levels.

At the bottom of the module are four white switches. You can't see it in the pic, but each has a funky lookin' symbol printed on it. The top button has a picture of a podium and is for talking to a conductor, in the case that I ever happen to have a symphony orchestra in our dirty little urban rock studio...hey, it could happen :D The second button down has a heiroglyphic-y looking couple tape reels and is a Slate button--this is for slating tapes with a distinctive frequency that makes finding locations on a tape easier. Third down has a headphone symbol and routes the talkback mic to Sends 5-6 for talking to people in their headphones (assuming the headphones are cued with those sends). The bottom button has a speaker symbol and routes the talkback mic to the Studio Monitors which I don't have hooked up, bit of a shame because I love a good God Mic :D

So, once again we see that this console has some unique (and occasionally confusing) routing capabilities that set it apart from other console layouts. I must admit that walking through all the functions in this thread is really helping me sort it all out in my head! Hoo boy, this console is unlike any other I've had my grubby paws on!

In the next installment, we'll see Alan get all wired up to the studio (or vice versa, as the case might have been), I'll talk a bit about running signals through to see what all did (or didn't) work on the console in the condition it arrived in, and then we'll move onto what I have dubbed The Great Re-Cap :eek::spank::p:drunk:
Yessir, I imagine it takes balls of steel to run a 500 with plasmas (and about a dozen backs of steel to move a 56...!) must be even more nuts than I am! :D GREAT looking console and room, Harvey! I didn't know you were running an MCI!
You seem underwhelmed by the EQ section, but let me just say this:

In the early days of recording, EQs were obviously primitive and crude. Engineers hated using them, and referred to them as "correctional devices".

Implying that the original performance, room, and mic placement was "done incorrectly" so as to require the "correctional device" in the signal chain. Food for thought.
Yessir, I imagine it takes balls of steel to run a 500 with plasmas (and about a dozen backs of steel to move a 56...!) must be even more nuts than I am! :D GREAT looking console and room, Harvey! I didn't know you were running an MCI!
Yup, MCI 556D in Studio A, Soundtracs 32x8 Topaz in Studio B, and SSL 4048 in the mix room. And yes, I'm way more nuts than all of you.
This is a cool thread. I spent a lot of time at Criteria in the 70s in front of their four MCI consoles (at the time) and never in my wildest imagination thought this stuff would end up in homes.. much less a home recording forum. I have lots of the original MCI brochures from back in those days that I should figure out how to post here someday.

That concept of storing the automation moves on two tracks of tape was developed (as I remember) by Michael Tapes and his buddy at Sound Workshop. Which as I remember, they then licensed to MCI. He used to yap to me about that at New York AES shows. For at least being workable, it was pretty cool automation at the time and some of the Criteria mixes using that system are still really cool to me.

Hey Harvey, did you happen to take any additional Buffalo Springfield pictures in 1968 other than the one used for the Acoustic promos? That one single pic is pretty cool and I can't seem to find it any more.
Hey Harvey, did you happen to take any additional Buffalo Springfield pictures in 1968 other than the one used for the Acoustic promos? That one single pic is pretty cool and I can't seem to find it any more.
I think I shot a couple of rolls of film; I'll check.
This is a cool thread. I spent a lot of time at Criteria in the 70s in front of their four MCI consoles (at the time) and never in my wildest imagination thought this stuff would end up in homes.. much less a home recording forum.

I hear you there! ...Though to be fair, I'm not a home recordist, I do this commercially and the console is installed in a studio space...guess I'm an odd man out here but I got some great, helpful console and tape machine advice here, enjoyed the friendliness of the forum and have stuck around...but yeah, it's a sight seeing 400, 500s and 600s all turn up in monster home studio rigs! In their day, I'm sure nobody ever imagined these things selling for prices so low as to be in the reach of home users and small/med market start-ups on shoestring budgets. It's certainly a testament to how the industry has changed! I looked over some paperwork posted on another forum and estimated that my particular 600, as currently loaded and optioned, would have cost about $55k new in 1980. Adjusted for today's dollars that's around $140k...and these were considered "cost conscious" consoles in their day! That doesn't exactly fly in today's markets :D
OK, since I'm waaaay behind on the "story," I'd better play a little catch-up and talk about getting this puppy wired into the studio. Being a co-op type space, we have lots of rack gear that needed to be wired to the patch bay via tuchels, studio lines to mic snakes in a big live room as well as our iso booth, and between the ProTools rig and analog 8-track would be wiring up to all 24 multitrack busses as well.

Here's the back of the console, so you can see all the empty Tuchel connectors waiting to have the studio brought to them! I won't be using ALL those connection points as there are more than 60 of them (this console is very flexible about how you wire to and route through it!), but certainly I will using a good half of them, and more when I eventually get all the mic preamps wired up with breakouts:


I also discovered that my console (as with most 600s) lacks the optional Mic Patching bay hence would need to add some breakout XLR looms to the Mic Patching Tuchels in order to get into the mic preamps. It was sort of an unpleasant log laid, but one must consider that this console comes from an era where the console was the center point (or heart) of the studio and lots of tie lines weren't very necessary, really just some compressors and reverbs there. Since the console was controlling the whole studio, it was expected that the mic lines in the studio rooms would be wired directly to the console's mic preamps via Tuchels. However, in today's studio setups where we're using primarily outboard, rack-mount mic preamps, Mic Patching is much more necessary. To start, I'm just making some breakout cables to 8 of the console's mic preamps. They're good pres, but we also have fantastic outboard rack preamps plus a re-capped and modified Yamaha PM1000 sidecar, so 8 of the MCI console's preamps is puh-lenty for now! I'm making up some batam-to-XLR patch ables to get into the preamps, since I decided to terminate the looms with XLRs so the patch bay could be bypassed as necessary and mics could be patched directly into the console--this is handy for tracking guitar amps, bass and scratch vocals right in the control room with minimal connection points.

Here's a photo of the patch bay. I labeled the tielines and multitracks as I wired them up and otherwise let the console's stock labels do their own talking. I took this pic later on in my install, when most but not all of the labeling was done. Not the tidiest job or the clearest pic, but it sure does tell you what does what...


Okay, so we already talked in an earlier post about the patch and how the studio is brought into it and the console via 30-pin Tuchel connecters which each handle 4 channels of inputs and four channels of outputs.

Here's a pile of used Tuchel connectors as I received them:


Typically during the uninstall, someone takes a bolt cutter to the looms and you end up with a short length of old cabling that needs to be de-soldered, pulled out, and the solder lugs cleaned up and ready for new cabling...and that's if you're lucky and get solder-type Tuchels! There were also crimp-type lugs which were intended to be a one-time use type wiring lug, but these days when the other option is to buy new Tuchels for $50-60 a pop(!), I decided not to be too picky.

Here's the scoop with Tuchel with solder lugs, old cable still on...then removed...then the Tuchel cleaned up and ready to be re-used:




And here are crimp lug type, shown with old cables snipped at the sleeve but old cable permanently stuck in the sleeve:


Most of the Tuchels I got were solder-type, but a handful were crimp-type. I developed a method of making the crimp lugs work by simply breaking the crimp sleeves off with an angled needle nose and soldering onto what was left of the lug:


Once the used Tuchels were all prepped and ready for a second (or third) life, the last thing to do was give the old contacts a good cleaning, as most of them were covered in a brown/black oxidation. My method was to spritz a shotglass full of Caig D5, rub it on the contacts with an old toothbrush (angled to get those molars oooo!), let it sink in for 30 seconds or so, then take a wire brush and scrub it all off...then a second coat of D5 for lubrication and protection. Here's my little Tuchel cleaning station:


Now, time to heat up the old Weller and get to work soldering the studio to the Tuchels. I talked in my first posts about all the work it took planning my wiring scheme in the most cost-efficient way possible, with lots of old rack snakes being re-terminated and re-used, plus certain new looms being made where necessary.

For the latter, we had a spool of Belden 8451 to use up, a bunch of old install looms to recycle which were mainly 8451 and Belden 1503A, and also some new spools of 500' each Gepco red (color code for inputs or "right") and black (for outputs and "left"):


A note on the install cable: between the above mentioned and all the various brands of pre-made snakes I was hacking up, I "got inside" lots of types of install-style cable. I'd previously been a fan of Belden, but after using Gepco I'll never go back--it's cheaper, strips and handles better, and also the jacket seems stiffer, is still a bit easier to work with and run. Far as I'm concerned, it's the install cable to get as far as fail shield non-copper cable goes. I'd have rather gone up a big notch to Gotham GAC2/1 high grade copper install cable, excellent stuff but more than 3x what we were getting the Gepco for which really adds up when you're after 1000'+....

Here's my little soldering station, ready for many loooooong days of snip, strip, solder...snip, strip, solder!!! Old surplus hospital bed roll around tables work great for this. You can cart them all over creation, adjust the height, etc. The salsa jar is a receptacle for the stripped bits of cable, de-soldering pump spitoon, etc. A good electric desoldering rig would have been really super duper here, and even more super dooper for the f'in re-cap, but it was NOT in the budget :(


So the first thing I wanted to do was get the control monitor Tuchel made up so I get run the console's oscillator and see what test tones were or were not getting where they needed to be, which VU meters did/not work and so-on.

I terminated the speaker input side with Neutrik TRS jacks because I actually just send the console's control room output at unity to an external studio monitor matrix since we have way more studio monitors than the MCI can accommodate, and because our ITB guys don't want/need the console for monitoring purposes.

My Phurst Tuchel (awwwwww):


Next were the multitracks starting with the ProTools converter ins and outs, so I could run up to 16 tracks and tones through the console line inputs and FINALLY get to gear what the console sounded like before I started re-capping. Here's a pic of a finished Multitrack tuchel. This particular one is actually temporary Hosa snake. It's a little too short and not good quality; my intention is to make a new loom with Gepco, but as it will swallow up a lot of cable, I used the Hosa as a stopgap so as not to run short on our install spools for other things. Little extra work in the end, but no matter!


Well, I had a 9-page wiring plan that I'd written up for the studio while waiting for the console to be transported, and I had several pages out of the console's manual showing which Tuchel did what and what each lug was supposed to carry, so I got down and dirty and spent a whole bunch of 8-10 hour days in Soldering Fiesta mode, all peppered with studio sessions going on, the simpler overdub sessions being scheduled earlier when fewer tielines were finished, and the larger scale tracking sessions coming later when more of the install was complete, so we weren't frustrated with lack of options trying to do our work while the studio was under re-construction!

Eventually, I had a nice--if incomplete--row of tielines completed, the Tuchel housings labeled with the devices they route in addition to small labels on each wire in the loom. This was to keep myself organized during the dizzying soldering process and also to make tracing any cable-related problems in the future simple to trace. Note the mishmash of snakes and looms coming out of the Tuchels, and how the cables get dual strain relief both out of the Tuchel housing, then by pressure as they hit the console frame "floor," then route out through a "cable chimney" in the frame and off to their various racks and studio snakes.


...and here are the multitrack looms all connected up--the first four are the 16-track digital rig (converters are RME ADI-8DSs, note they're half NICE EWI snake looms and half temporary Hosa) and the next two are the analog 8-track looms, then also our HHB Cd burner which is routed through the (stereo) TAPE MACHINE 2 patches with a color coded Gepco loom, and the control room monitor outputs via Belden 8451. I want to upgrade these to Gotham GAC-2/1 at some point!


More to come including "how does Alan sound??" and The Great Re-Cap including video!
Simply awesome Brian...nice work.

Hey wouldja let me know if you end up with any surplus Gepco install cable? I'm going to need a bunch for recreating the internal harness on my JH-416.

I too like Gepco. The price is right, its easy to work with and I've had no trouble with it...the specs are good too.

I can't wait 'til I'm doing what you are doing though I'll be punching snakes into my QCP punch panels instead of the Tuchel saga. MAN! Yer an animal.

Oh, and BTW, my Ampex MM-1000 would have cost over $200,000 in today's dollars. I've spent well less than 1% of that on it.
Hey wouldja let me know if you end up with any surplus Gepco install cable? I'm going to need a bunch for recreating the internal harness on my JH-416.

Can do, though will probably use what's left on the new multitrack looms, mic preamp breakouts and a few odds and ends. The mic patching thing wasn't something I'd figured out yet when the install cable got ordered...d'oh! :o

On a side note, the nice bonus about switching to a hard wired patch bay and reconfiguring the rack looms is that I came out of the install with a box full of TRS and XLR connectors to be re-used! Phew!

I can't wait 'til I'm doing what you are doing though I'll be punching snakes into my QCP punch panels instead of the Tuchel saga.

It's great to have the motivation of "I'll get to hear this thing!" when doing the wiring! I don't miss our old 1/4" bay either! You won't miss the Tuchels :spank:

Oh, and BTW, my Ampex MM-1000 would have cost over $200,000 in today's dollars. I've spent well less than 1% of that on it.

I love figures like that :D
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Where did you get your Gepco cable? Redco has it in all colors of the rainbow for $0.14/ft. That's probabl what I'm going to do because then I can make up the harness in the original colors MCI spec'ed.

Yeah this whole wiring thing with this caliber of console is just a new and interesting thing. And yes it makes a WHOLE lot of sense when you think about the jack panels in the recording rooms as essentially a remote jack panel for the mixer, so why would you have jacks on the mixer too? Same thing at church...we have a Allen & Heath GL-3300-32 there. It has a jack panel on the mixer of course but the harness is permanently plugged in inasmuch as we don't mess with it. People on the platform either ask or we tell them where to plug in. There's the mic patch panel. I'll have things pretty well permanently patched as far as mics go in my studio since, unlike you, I'm not operating a business, but if something needs to change I'll just move it on the fan. If something more significant changes with how I want mics patched then the QCP punch panels will be appreciated. Yank, trim, strip, punch, done.

I must say, though, yes the Tuchel's seem like the bane of the late model MCI owner, but the Tuchel jack rack on the back of your JH-600 is...cooooooool. :cool:

Brian, what is the module with the transistors above the power terminals at the lower right of the back of the console?

On a side note, the nice bonus about switching to a hard wired patch bay and reconfiguring the rack looms is that I came out of the install with a box full of TRS and XLR connectors to be re-used! Phew!

Yyyyyeah...I'm gonna have a crap-ton of cable-mount jacks at the end of this thing. :o Maybe they can help fund my harness cabling needs. :D