Improving Ultra-Rare Legend LE414 Speaker Control Selector Switch Assembly

November 26, 2018

#291

Gentle reader,

After the more than forty year journey building the best sounding stereo system that I could afford, I have tried a LOT of components of all kinds.

I have determined, that for maximum signal contact, banana plugs cannot be beat for speaker wires and cables. Below shows several types and brands of terminals one can use instead of bare wire. The forked ones are called Spade Lugs.

Above are examples of the many types of plugs I have tried. The one laying down in the middle is a double-banana plug.

After MANY tries with various brands and styles, I decided these from Nakamichi to have the greatest contact area and firm hold.

However, sometimes they hold too tight. So, lately, I have been using these:

The one drawback is that the bodies although painted are still conductive. Fortunately, my amps have built-in protection which automatically resets. There are many fake Nakamichi plugs made largely in China. So if you like what you see here, look carefully at their design.

These are the double banana plugs which are coming that will be used in association with the speaker control switch below.

If I need a speaker switch, I want one that uses banana plugs.

Some years ago, I came across a LEGEND LE412 Speaker Control. It had three-way binding/banana plug terminals, a unique style and look. So, I bought it. 

Soon after, they may have stopped making them, or so it seems. I could not even find a photo on one!

What you see here, is only the SECOND LEGEND brand speaker switch that I have ever seen. So, naturally when I spied it on eBay, I bought it. 
It is the LE414 and switches FOUR pairs of speakers.

They cleverly used clear rubber feet to cover the screw holes on the bottom. One was missing, but that is not a problem.

See what I mean, a clean and unique design, well thought out and executed.

Measured top-to-bottom, the terminals holes are the industry standard 3/4 of an inch apart. Which means using double-banana plugs is an ideal solution.

The problem is, they assembled it with the + and - terminals going left to right, not top to bottom. Side-by-side, they are less than 3/4" apart.

So, I fixed that. Let me show you how I did it. And if you are fortunate enough to EVER find one of these LEGEND Speaker Controls, you too can make it work better.

First, pry off the clear rubber feet. A utility knife, Xacto knife or sharp tweezers will free them from the bottom cover.

Using a #2 Phillips screwdriver, remove the four screws and set aside in a safe place so that they do not get lost.

Lift off the top and if it is the 414 model, this is what you will see. The 412 is simpler since it has half of everything.

A "bundle of snakes" could describe this mess of wiring. This is 600 volt rated wiring, so it will easily handle large amplifier's output. My LE412 has never given me trouble.

I meant to measure these resistors, but it slipped my mind. They are fairly large so they can handle a lot of current. Do you know how to read those stripes?

Three #2 Phillips screws secure the board to the case's base. Set them aside as well. They are shorter than the main screws, but the same diameter.  

They wisely added a steel plate to the base to stabilize the unit, but it is not enough weight. Well, not if you use 12 gauge speaker cables like I do.

Once freed, the assembly shown starts to make sense. All neatly done. Note the terminals are double-nutted. This keeps them from loosening.

NOTE also the factory setup of RED-BLACK-RED-BLACK, etc.,  from left to right.

The first thing one must do to reorient (re-Asian?) the terminals is to trace each pair of RED-BLACK and wire-tie them together and label them as I have done below. 

NOTE: The board where each pair of wires passes through is marked as to which goes where which should help.  

Since they are three-way binding terminals for the speaker wires or cables, one can use bare wires through the holes, spade terminals, even ring terminals in the case of these since the plastic/metal nuts can be completely removed. I, of course, use banana plugs. 

The photo above shows how I used a #1 Phillips screwdriver passed through both terminals to hold them for loosening and tightening the nuts. Taking the red and black nuts all the way off is not necessary, however. NOTE how thin the metal is. Proceed carefully.

It is VITAL to do one set (four wires/terminals) at a time so as to avoid mixing up the wires.  ABOVE shows the new orientation with the black wire(s) on the bottom and red ones on the top. NOTE that I secured them differently: Washer, nut, ring terminal and then the second nut.

BE VERY CAREFUL when tightening the nuts! These are very thin terminal barrels and I broke one. Fortunately, I kept the old ones from my LE214 from when I upgraded that unit to heavier duty terminals. 
I was forced to do that since I was using the Nakamichi banana plugs with a zig-zag slot cut in them rather than the traditional spring design bananas. While that type offer the best conduction, they are hard to get in or out of terminals and I snapped a few of the terminals on my LE412 as a result. 

Above shows the new orientation, RED on top, BLACK on the bottom and the screwdriver in place holding the two terminals parallel so that the wire holes line up with the grooves LEGEND molded into the back panel to allow for easier inserting of the speaker wires. NOTE, that these can only accept fairly thin gauge wires.

Above shows all of the wires and terminals in their new locations. I marked the RED terminals with an "L" to remind me which is right and left. NOTE all of the cable ties and flag labels that I made still in place at this time.

While the silver stickers denoting what plugs in where are still valid, the factory R and L markings (on the ends of the back panel) no longer apply. Thus, the L I wrote on every other nut.

I snipped off each wire tie with small wire cutters prior to reassembling the components.

With my digital-VOM, I checked each right and left terminal using each switch as I went along to assure that they had continuity. 

Photo below shows the improved LE414 it in place for testing. I hooked it to my Yamaha receiver. That is the PC on which I create. Smeagol (Gollum) says hello.

Using a pair of jumper cables equipped with banana plugs, I hooked it to my Yamaha and made sure each channel worked for all four pairs of terminals and switches.

As we have seen, there are two resistors on the board, I assume to add resistance since this is a parallel circuit switch. However, I would still not use more than two pairs of speakers at a time, even though one can press all four switches in.

I have those twelve new double banana plugs coming (shown near the top of the article) which I will be using with the switch.  Their design will help to prevent breaking the sadly thin metal barrels of these terminals.

As I wrote above, the internal steel weight is insufficient to hold down the front of the speaker control if using heavy cables. I added these weights to my LE412. But still have to use reusable adhesive like BluTak underneath to keep it from "popping a wheelie". I don't remember where these weights came from, but they are the type of things I keep, "I might need these some day."

I am now using my LE412 as a switch for the Realistic Audio Power Meter 300 shown above. Which allows me to monitor either A or B speakers being used.

I have six speakers in my system in the listening room. Klipsch KG4s are the main ones and a pair of Advent Baby Advent II wired through a Dynaco QD2 and a pair of Dynaco A25XLs as the surround speakers. 

The Dynaco QD-2 has passive internal circuitry to protect the amplifier from too low of resistance while creating an ambiance and much greater depth to the soundstage.

The 1990's QD-2 is an improvement on the 1970's Dynaquad which used simple circuitry to "free" ambiance and the acoustics of the recording space used.
This version is an improvement and adds a center channel which can be switched out. 

Previous models were called QD-1 Series II and lacked these three-way binding/banana terminals. Using cheaper plastic spring terminals.

In place between my Dynaco PAT-6 preamp/tuner and ST-200 power amplifier and wired. I use Monster Cable Z-Series speaker cables. 

As I stated, the QD-2 has circuitry designed to add resistance so that when using all four speakers, the total resistance does not fall below four Ohms.

Here is a recent photo of the listening room's system and front speakers. Not seen are the two Dynaco A25XL speakers on stands made from bamboo which flank my chair on the side walls. The soundstage fills the whole room. I love it.

Wooden Speaker Stands and Risers too Expensive? Try Bamboo Stools. How-To Guide. 

The link above shows the bamboo stands which are actually stools which I repurposed to raise the A25XLs closer to ear level. The stands (above) under the Klipsch KG4 speakers are also made from bamboo. The factory bases were too low for me.

I hope that you have enjoyed my latest project. I have replaced spring terminals with three-way binding/banana terminals (look at the photo with the switch on my PC) before, so if you want to buy and try one of the Dynaco QD-1 Series II units, it is possible to do.

Thank you once again, for taking the time to read my words and view my images. You are the reason why I spend hours documenting my adventures.

Scott
November 26, 2018
#291