I NEED HELP! I can't figure this out

Okay, so I had tried modding the 7506, and I got it soldered and wired up… but now it wants to come out as MONO!!! I’ve unsoldered everything, and resoldered, and it seems that when i remove all the wires comming from the outside (the ones going to the other side have been left alone) and wick away all the solder from the pads… all the pads have continuity with each other, and I DON’T FUCKING KNOW WHY

Photo or it didnt happen (as in we prob cant help) unless there is a sneaky trick Im missing

That is bad.
Could be molten insulation or solder on the corner of solder tracks/pads bridging out. Get a magnifying glass and flash light to check.

How about video?

I don’t think so, but that doesn’t mean I’m not missing something


I am genuinely concerned that I botched it now…

What is that meter set to?
Because if that is 200m Ohm, then of course that gives you full tilt.


Pictures look fine to me.

The setting that says OHM X1K is what I turn it to. Beyond that, I try to have it zeroed out (the needle hits the far left indicator when I don’t touch the probes together, but hits the zero on the far right when I hold them together)

So, to my understanding that means the left of the scale is 1000 Ohm, center is 500 ohm, far right is 100 Ohm.

Edit: God why?
image

You don’t happen to have 250 or 600 Ohm headphones on hand to check? (through the cable is enough, no need to open anything)

So, thing is, the 1 on the scale means 1000 Ohm, 1k on the scale is 1,000,000 Ohm.

Do you have a AA (or AAA) cell and a metal paperclip on hand?

And of course my DT 990 Pro is back in my dorm… Damn it… I think the highest Ohm headphones I have on hand is my Dekoni Blue

AA yes, and I can check for a paperclip

Edit: Not finding a paperclip off hand, though was considering running over to the store in a minute. What are you thinking about having me do?

This:

Ohm = Volt / Amps

So for a given voltage the current flowing gives you the resistance

Example:
1.5 V / 0.022 A = 68 Ohm
Including measurement error, that is close enough to the 60 Ohm the Porta Pros should come in.

Edit: Don’t need a paperclip… Was thinking of a different “bodge-setup”
Edit2: Yeah, I know. Bench PSU on hand but not a AA-battery

I would be lying if I didn’t say that didn’t leave me confuzzled… Or that I’m not getting the feeling that i shouldn’t have cheaped out, and just gone for a higher model like one of these:


Let me see if I can find a battery…

  1. Measure the Voltage (DC) of the battery and write it down (or memorize it)

  2. Measure the Current (DC A, set it to 50)

  3. You should come out about here:
    image

You then take your battery voltage (in my case 1.2V) and divide that by the current (0.020A) to get 60 Ohm (or whatever your headphone has).

*pushes away 80€ worth of test leads* Nah, it is fine.

I’ll admit, that made me chuckle. I’m sitting here with a $9-10 USD (7.6-8.44 Euro) unit, wondering if I shouldn’t have gone for a $22-30 USD (18.58-25.33Euro) unit that will set at x1 as well, rather then just x1k, and others are sitting there with equipment several tiers higher then what I’m thinking I should have gotten.

I added better (as in adopted for battery on hand) instructions.

Hope that helps :slight_smile:


We all start somewhere.

I’m hazzarding a guess that the top is V(in which case it ig going to ~54(which doesn’t make sense as AA is supposed to be 1.2V)(there are ten marks between each numbered mark, so 6 for each mark on top, 3 for each on the bottom) when I set the dial to 10) and the bottom is A(which when set to 50, it goes to 78(measured with my Dekoni Blue, which according to Fostex, is supposed to be 50ohms))

Welcome to the wonderful world of analog multi meters. You look at what you set to measure, then find the corresponding value on the scales.

1.2V then comes out at 1.2V

Okay, so 1.8V and 78A, so… 43.3Ohm? Okay

Not bad for a DIY setup.

I’m failing to see how this is going to help me figure out what the hell is going on with my 7506