middleaudio.com

Wow cool. I AM made of 40 dollar bills!!

I apologize for my question being redundant, but I just wanted to be sure I wouldn’t blow anything up. I’ve managed to accomplish a fair amount in the audio world using common-ish sense, but the underlying theory is still largely wizardy to me and I’m often hesitant to try anything beyond what I already know for fear of damaging things.

I’ll be in touch with FAG about the box.

gamblor wrote:I’ll be in touch with FAG about the box.

I think your rate just went up

So to recap and simplify things for people who will not bother to read the whole thread, I don't even think I have.
Signal connections must always go from low to high so as not to load the output device. A 1:10 rule is good. For example when I built Christian's 'PAD' I designed it with an I/O of 10K. The output impedance of his mixer being in the hundreds saw a load of 10K and the pad having an impedance of 10K saw a load of 1M at the pedal, both instances the 1:10 rule was followed and no loading occurs.
The other factor is level which was handled by the 25dB pad designed in. The simple thing about Christian's device was that it stayed as an unbalanced T-Pad and he will not be using long cable lengths, so this will work, the 'cold' ring connection on his mixer's aux output will simply be ignored if he uses a TRS plug or shunted to ground if he uses a TS plug.
Gamblor has asked me to build him a reamp box. Assuming he plans on driving extended lengths from his recorder's balanced output to his amplifier in another room I will have to construct something that will handle the level difference, load properly, AND take care of properly unbalancing the signal. He also wants the whole deal for under $60.
Stay tuned.........................................

Hey Alain. Thanks for the summary. To clarify, I set the $60 price assuming you were building the same unit as Christian’s. Now that I understand the differences, don’t hesitate to set a fair price for the reamp box!

OK. Update.

To passively unbalance a signal you kinda need a transformer. Transformers are expensive. I searched high and low and found one with decent specs for a reasonable price. I have a circuit in mind that would add level AND impedance controls. Don't know if I will go this fancy cause I still need to supply an enclosure and connectors but we'll see. Obviously I will not make a cent on this but I accepted the challenge and it's a good thread.

Okeley dokeley, all done and working fine and quiet. I took the level and impedance or 'drag' controls and set them permanently at noon.
Also the ground is forever lifted. I have enough parts in stock to build a few more but they won't be $60.

So no variable level or impedence?

No like I said, at $60 dollars that barely covered both connectors, the case AND the transformer. I basically substituted the pot values (r) for two resistors (r/2) with a center tap.
I have enough parts to make myself one with all the bells and whizzlers though.

You are the man Alain!!

The Redeye will do all that except for variable impedance won't it? How much for a full featured version?

$100 plus whatever transformer you wanna have in it.