Telefunken Tape Machine Level Matching

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What tape speed and level did you do the frequency response test?

If it was 7.5ips (19cm/s) you need to do it at no higher than -10dB on the VU meter. At 15ips/38cm/s you can do it at 0dBu.

Cheers

Ian
 
Hey Ian,

i did it at 19cm/s and 0dbu (1.228V) approximately. I'll check that and then try -10db.

THANKS & Cheers!
 
Hey Guys,

need some help here again...
I'm struggling at one point...

The units output is unbalanced (DIN 5 pol).
As Abbey pointed to a wrong connection, I changed to a unbalanced Cable for connecting the interface (patchbay)... higher input level; fine.

Ok, according to RANE-Notes #110 unbalanced to balanced (case #14) is TIP->TIP, Shield -> RING.


ROCK-ON!
 
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Hey,

the box isn't wired (properly) jet...
I try to figure out what would be the best way...
Till now I used an unbalanced TRS cable (TIP to TIP, Ground to RING) for testing.
But in the end I would like to use (if it make sense) my balanced patchbay cables, no cable mix.


Thanks!
 
Hey Guys,

an afternoon later of pulling my last hair out and getting totally lost at some point...

I found out that my DIGI002 Interface outputs seems to be Pseudo-balanced (I'm only getting on tip a signal), even the manual says "balanced outputs".

Now everything seems to work fine. Sending Sinus [email protected], getting back [email protected] approximately :)
Here's a quick drawing of my wiring (following RaneNotes).

Next, I'll see what I can do on the high frequency response...


THANKS &
ROCK-ON!
 

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Quite a lot of interfaces these days have impedance balanced outputs. This means the hot is connected to an op amp output (usually via a resistor) and the cold is connected to analogue 0V via a resistor of the same value. This is why you only see a signal between hot and ground.

Remember, a balanced signal exists only between hot and cold. In a balanced cable, the ground is NOT a signal carrying conductor, it is a screen. The voltage between hot and ground and between cold and ground is NOT defined so don't even expect then to exist let alone be the same.

Cheers

Ian
 
I like to tell the story till the end... (is this the end...?!? ;))

A quick idea for a little box for goofing with the old tape machine... ended up in much more work than expected and opened a door to a new world (reel-to-reel)... :)

Thanks again for helping!!

ROCK-ON!



P.S.: I did some tweaking on the heads position (more or less trying around) and could improve the frequency response quit a bit. Not perfect, but I think ok for the moment... we'll see...
 

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Hi,

i have to share it.
I gave my unit to some "real pro" o_O for maintenance.
They did an absolutely great job!! WOW & Thanks...

If you're in Europe, Germany check out:

tge-essen.de


Now everything's work's like a charm! .... but i need more time in the playground...:D


ROCK-ON!
 

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