Anyone know the impedances and turns for the VTB9045 and VTB9046?

I just can't seem to find the specs anywhere. The info on audio maintenance site just gives pin out and physical dimensions, not turns ratios or impedances. Google search just keeps pointing to here and AML site.

I've built the EZ1290 project and want to add a switchable tranny instrument input (rather than a DI stage) - the VTB9046 would be the natural choice but given the costs I want to look at alternatives such as Lundahl, OEP etc.

http://www.technicalaudio.com/reading/neve_xfmrs/neve_edo7113.html

Collin gave me this usefull link , according to him , everyone uses this as reference.

Many thanks RedNoise.

For future reference of those finding this thread:

Carnhill VTB9045 is the equivalent of the 10468 Mic input tranformer

• Primary coils: 600R 300R each (1K2 in series, 300R in parallel)
• Secondary coils: 2K4 1K2 each (4K8 in series, 1K2 in parallel)

Carnhill VTB9046 is the equivalent of the 31267 Line input tranformer

• Primary coils: 4K8 2K4 each (~10K in series, 2K4 in parallel)
• Secondary coils: 1K2 600R each (2K4 in series, 600R in parallel)

[EDIT:] Corrected the impedances of the indivual coils in above text.

Is that Rutger Hauer in Bladerunner? Cool film.

transformer windings in parallel do not halve the impedance.  two 600 ohm windings in parallel still give 600 ohms.

transformer windings in series do not double the impedance.  two 600 ohm windings in series give 2.4k ohms.

impedance is the square of turns.  so two 600 ohm windings in series is 2 (double the turns) squared times 600 (or 2.4k).

check the chart linked in this post.

ed

Ed - Thanks for putting me right on that - I'll update the earlier post I made.

I mistakenly worked the individual coil impedances back like series/parallel resistances. DOH!

Please forgive the absolute noob question, but would it be safe to assume that the vtb9046 transformer would be wired in the same way as the vtb9045?  Same pins jumpered, etc? I looked at the technical page and that seemed to make sense to me but wasn't sure if there was something I may be overlooking.

Thanks

Seems the answer is yes.  Glad work is slow today