REPRO Passive reamp Box Build Thread

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REPRO Passive reamp Box Build Thread

Postby Joe Malone » Sat Oct 11, 2014 4:11 pm

New Black Case Version (Build is the same as old version below)
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OLD Version Case
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First unpack kit and check you have all the parts below. Plus box back panel not shown in photo.
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Start assembly by fitting the Female XLR inside the case.
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Use the 2 black self tapping screws to hold it into position.
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Fit JLM14 transformer into plastic clip
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Remove protection plastic from double sided tape on clip
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And stick to box hard against the top edge and as close to the XLR as possible
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Screw ground lug to transformer with lock washer, ground lug, lock washer and 3M 6mm screw in that order.
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Fold ground tab on XLR 90 degrees and solder to transformer ground lug.
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Pre solder XLR pin 1 and strip the end of the spare green wire and solder to XLR pin 1
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Cut green wire about 10mm away from solder and slide off green plastic.
Twist wires and solder to XLR ground tab.
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Pre solder XLR pin 2 and pin 3. Twist blue and yellow wires tightly and solder Blue wire to pin 3 and Yellow wire to pin 2.
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Fold legs of TRS jack as shown below and fit the 2 fibre washers.
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Fit into hole in case.
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Use black dress ring and chrome nut to tighten to case.
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Pre solder the 3 legs sticking out of the TRS Jack.
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Cut pot locating tabs from the 1k and 100k pots.
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The 2 pots will go into the case as shown with 1k on left and 100k on right looking from on top.
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It is worth writing the pot values on there back covers as you will not be able to see these values once fitted in the box.
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Fold centre wiper lug down as shown on both pots.
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Fit both pots as below and by adding the washer and nut to each and tightening down.
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Solder pot centre wiper lugs together.
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Tightly twist transformer Red and Green together and wrap tinned wire ends to 1k pot as shown.
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Solder Red wire to volume pot lug. and add second stripped and soldered green wire supplied into volume pot lug with transformer green wire.
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Solder both green wires in the volume pot lug.
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Strip and solder end of orange wire supplied to impedance pot lug as shown.
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Twist orange and green wires together.
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Cut twisted orange and green wire down in length so they reach the jack terminals with a bit to spare. Strip and solder both wire ends.
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Solder green wire to bottom TRS jack terminal. And solder orange wire to top TRS jack terminal as shown.
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Cut black wire shorter and slide end back into the black heatshrink tube so it will not short to anything.
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Cut transformers plastic clip down so the diecast lid just presses on it when fitted.
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Double check your wiring and trim any sharp points on the end of any soldered wires.
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The reamp box can now be tested. In and out and controls are as shown below. Setting level and impedance pots to half there travel is a ideal starting point.
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If the box works and you are not going to paint it now it is time to fit the knobs, logo, labeling & back of box.
Labeling can be done with dymo/brother labeling or by hand with permanent pen.
You could use any of the terms listed LINE INPUT = INPUT = IN. AMP OUTPUT = OUTPUT = OUT. VOLUME = LEVEL. IMPEDANCE = Z. etc
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Joe :-)
JLM Audio
Capturing Audio without Injury

Lachie
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Re: REPRO Passive reamp Box Build Thread

Postby Lachie » Thu Jun 15, 2017 1:47 pm

Is it possible to add a second 1/4" unbalanced output to these by just piggy backing another jack onto the first?
Or perhaps more complicated?
Thanks
Lachie

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Joe Malone
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Re: REPRO Passive reamp Box Build Thread

Postby Joe Malone » Thu Jun 15, 2017 2:43 pm

Lachie wrote:Is it possible to add a second 1/4" unbalanced output to these by just piggy backing another jack onto the first?
Or perhaps more complicated?
Thanks
Lachie


Yes you can parallel a second jack directly across the first jack.

If you get hum loop when using 2 amps only connect the tip to the second jack.
Joe :-)

JLM Audio

Capturing Audio without Injury

Lachie
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Joined: Wed Jul 10, 2013 1:39 pm

Re: REPRO Passive reamp Box Build Thread

Postby Lachie » Thu Jun 15, 2017 2:51 pm

Legend, thanks Joe.
Any easy way to avoid that possibility?

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Re: REPRO Passive reamp Box Build Thread

Postby Joe Malone » Thu Jun 15, 2017 5:48 pm

Lachie wrote:Legend, thanks Joe.
Any easy way to avoid that possibility?


Yes use 2 x REPRO boxes :-)

You will find the second socket will never need the 0v ground if the amps are mains powered with earth pin plug.

But you can add a ground lift switch to switch the 0v on to the second socket or not.
Joe :-)

JLM Audio

Capturing Audio without Injury

Lachie
Posts: 10
Joined: Wed Jul 10, 2013 1:39 pm

Re: REPRO Passive reamp Box Build Thread

Postby Lachie » Fri Jun 16, 2017 1:32 pm

Ha, yep. Thought that might be it.
That's definitely the plan, though I'd like to build a few into a 1ru chassis as it's more functional than a reamp box to me.
It'd just be nice to be able to have a single reamp channel be able to feed 2 amps/pedals rather than use 2 REPRO channels on the one source.

I know this is off topic but can you point me to the best kit of yours for a simple 2:1 balanced mic mixer w/volume controls for each input?

Thanks again!

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Re: REPRO Passive reamp Box Build Thread

Postby Joe Malone » Tue Aug 01, 2017 12:05 pm

Lachie wrote:Ha, yep. Thought that might be it.
That's definitely the plan, though I'd like to build a few into a 1ru chassis as it's more functional than a reamp box to me.
It'd just be nice to be able to have a single reamp channel be able to feed 2 amps/pedals rather than use 2 REPRO channels on the one source.

Use the second socket with only the tip wired trick it will work ok but just not as quiet as 2 transformer isolated output will.

I know this is off topic but can you point me to the best kit of yours for a simple 2:1 balanced mic mixer w/volume controls for each input?

Thanks again!


Check out our new STATTEN kit for making passive mixers with level and/or pan pots

https://www.jlmaudio.com/shop/index.php
Joe :-)

JLM Audio

Capturing Audio without Injury

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