Toroids for line level outputs

[Brian Roth]

The recent thread on the topic of toroids seems to have degenerated into "how many angels can dance on the head of a pin?" Before it derailed, I mentioned several examples I have seen in Neve, Amek and ADM desks where toroids were used in circuit locations providing line level signals into the outside world.

I am curious about various line level output applications to learn more about pluses and minuses. I don't want to read that they sound "more 3D" or "sweeter" or end world hunger and cure male pattern baldness. <G!>

Why DID Neve and ADM decide to use them????

Bri

EDIT: I just recalled seeing this Carnhill item recently:

www.audiomaintenance.com/acatalog/CA-18-VTB9076_extended_info.html

 

[rock soderstrom]

I am curious about various line level output applications to learn more about pluses and minuses.

As I wrote in the other thread, Haufe (Pikatron too) produced toroidal signal transformers for all suppliers of German broadcast technology. These were then used in almost all modules from mic pres, line and mixer amplifiers to headphone amplifiers. This is especially true from the beginning of transistor and Opamp technick, actually until today.

If you are interested in the actual implementation, you can find numerous examples on kubi's site. Neumann, Telefunken, TAB, ANT etc. all used toroidal transformers on a large scale, not only as line output transformers but also as microphone and line-in iron.

Here as an example, the multifunctional buffer amp Telefunken V672/2 with two output transformers.



However, I can only speculate as to the exact reasons why toroidal technology was chosen at a certain point in time. There were clearly strong advocates for this technology, perhaps costs and simpler production methods were reasons for this decision. The V672 is a good example, since its predecessor also had square transformer cores.

 

[j.colt]

The Nagra QSSF that adds balanced out to Nagra IV-S uses two Nagra-made toroids: if they did it, it must have been the best option for this particular application