XLR(m) to XLR(f) Bleeder Resistor

[Diaultras]

Hello

I need to protect IC gear down the line of a tube compressor.  The 100 CM from Rapco Horizon is expensive.
As I have xlr barrels I’m planning just to do it myself.

Where to solder the 100K resistor?
Pin 2 to Pin 1? 
This will change the output impedance?
Pro and Cons?

Thanks for advice.

 

[Khron]

What exactly are you trying to achieve, and why / how?

 

[pucho812]

I am not sure what he is asking other then he wants to connect 2 pieces of gear together, one has IC chips and one is a tube compressor.  Looks like he is planning to use 100CM rapco if that is even a part number? or he is using 100CM (around 3 feet)of length of cable.  Either way he will be fine if he just wires up a cable between then gear and is done unless there is a puzzle piece missing.

 

[RuudNL]

As long as the tube equipment has a transformer (balanced) output, I don't see a problem when connecting this output to semiconductor (IC) equipment.
But when the tube equipment has an unbalanced output (capacitor from plate or cathode to the output) I can imagine that you are a bit worried.
In the last case you should first get an idea of the maximum output level of the tube device.
I could imagine that two zeners in series (with reverse polarity) would short out most unwanted high voltages.
In general, IC equipment will survive a voltage of + or - 15 Volts on the input.

 

[Diaultras]

What exactly are you trying to achieve, and why / how?

Here:

https://www.rapcohorizon.com/product/155/d-box-terminator

 

[Diaultras]

As long as the tube equipment has a transformer (balanced) output, I don't see a problem when connecting this output to semiconductor (IC) equipment.
But when the tube equipment has an unbalanced output (capacitor from plate or cathode to the output) I can imagine that you are a bit worried.
In the last case you should first get an idea of the maximum output level of the tube device.
I could imagine that two zeners in series (with reverse polarity) would short out most unwanted high voltages.
In general, IC equipment will survive a voltage of + or - 15 Volts on the input.

Yes it has balanced outputs, but without bleeding resistor at the output tranny.

Will the zeners do not affect sound or impedance?
Any idea what value would work?

 

[RuudNL]

If there is an output transformer, there are no zeners or resistors needed IMHO...

 

[pucho812]

o.k. I got it....

that d-box you link is a DMX terminator and under DMX terminators.
It's for DMX applications.
"DMX is a lighting control protocol which allows users to have ultimate control over their lighting needs. ... DMX originated as a way to set the bar for lighting manufacturers to build fixtures that would all be compatible with each other, instead of having individual control stations for each set of lighting"

DMX cables can come terminated with 3 pin xlr's...

Now what two boxes do you wish to connect together.  if both are pro audio manufactured boxes, you will be fine without any special things.

 

[Diaultras]

If there is an output transformer, there are no zeners or resistors needed IMHO...

Thank you RuudNL. I heard that it would.  If I want to do what rapcohorizon do, where is located the 100K resistor? Pin 2 to Pin 1?

 

[Diaultras]

o.k. I got it....

that d-box you link is a DMX terminator and under DMX terminators.
It's for DMX applications.
"DMX is a lighting control protocol which allows users to have ultimate control over their lighting needs. ... DMX originated as a way to set the bar for lighting manufacturers to build fixtures that would all be compatible with each other, instead of having individual control stations for each set of lighting"

DMX cables can come terminated with 3 pin xlr's...

Now what two boxes do you wish to connect together.  if both are pro audio manufactured boxes, you will be fine without any special things.

Thank you for commenting, Pucho!

This:

"In certain instances, equipment using “retro” and “vintage” design topologies may damage DC-coupled input stages, like those used by Dangerous Music and other high-end pro audio manufacturers. This occurs specifically when the manufacturer does not modernize the output stage to be compatible with the transistor/IC world of today."

I just want to know if the solution of 100K resistor will work. I have a mastering vintage tube compressor and I am worried. Otherwise I will have to adapt a 5W bleeding resistor at the B+ to ground (ohm law willing).

 

[ruffrecords]

Thank you for commenting, Pucho!

This:

"In certain instances, equipment using “retro” and “vintage” design topologies may damage DC-coupled input stages, like those used by Dangerous Music and other high-end pro audio manufacturers. This occurs specifically when the manufacturer does not modernize the output stage to be compatible with the transistor/IC world of today."

This sounds like marketing speak to me. Who exactly said this?

Cheers

Ian

 

[Diaultras]

This sounds like marketing speak to me. Who exactly said this?

Cheers

Ian

https://www.gearslutz.com/board/high-end/1021142-shadow-hills-mc-dangerous-gear-killer.html

 

[moamps]

Where to solder the 100K resistor?

You can use here two resistors, from pins 2 and 3 to pin 1. They are used just for discharging a static voltage on secondary vs. ground.
@pucho812
DMX termination is 120ohms  between  pins 2 and 3.

 

[pucho812]

You can use here two resistors, from pins 2 and 3 to pin 1. They are used just for discharging a static voltage on secondary vs. ground.
@pucho812
DMX termination is 120ohms  between  pins 2 and 3.

yes o˚. but the rapco device he pointed to is listed under a DMX terminator on their website.  which I was just pointing out that might not be what he wants.

as wouldn't worry about it until it's a problem

 

[RuudNL]

Of course you can do anything you want.
But it is not needed and it won't cause any problems...

 

[ruffrecords]

https://www.gearslutz.com/board/high-end/1021142-shadow-hills-mc-dangerous-gear-killer.html

Gearslutz is not exactly renowned for accuracy. I notice the guy from dangerous is reported as saying:

I

f any of your outboard that you wish to connect to Liaison has a
“floating output,” a qualified tech. can add what are referred to as
“bleeder resistors” to the transformer outputs. Parts cost about 15-
cents!

Must be a very poor design if it cannot cope with a floating output.

This is very strange because at the dangerous web site they say:

Audiophile-grade components are used throughout the LIAISON’s 100% passive analog relay switching system,

Which is by definition floating.

Cheers

Ian

 

[[silent:arts]]

Cool. All my gear can be claimed as potential dangerous gear killer  ;D

 

[ruffrecords]

Cool. All my gear can be claimed as potential dangerous gear killer  ;D

Good idea. I think I will add a notice to all my tube mixers to to say "Do not use with gear made by Dangerous due to their inability to cope with professional standard signals"

Cheers

Ian

 

[RuudNL]

;D

 

[abbey road d enfer]

"In certain instances, equipment using “retro” and “vintage” design topologies may damage DC-coupled input stages, like those used by Dangerous Music and other high-end pro audio manufacturers. This occurs specifically when the manufacturer does not modernize the output stage to be compatible with the transistor/IC world of today."

Let's be frank: this is pure marketing BS. If a piece of gear leaks current, it is defective, and as such should be fixed before being put in service. Installing 100k resistors is NOT a substitute for recapping.
I hate people who exploit the credulity of the public.

I just want to know if the solution of 100K resistor will work. I have a mastering vintage tube compressor and I am worried.

Did you check if it's leaking? If not you don't have to worry, if yes, fix it.

Otherwise I will have to adapt a 5W bleeding resistor at the B+ to ground (ohm law willing).

That won't help a potential leakage issue in any way. Who suggested that stupidity?