Urei 16-12614 Transformers

[JMan]

Hello All,

I have what I fear may be a rather ignorant inquiry, but a fair amount of Googling and yes, using the search function here, has failed to yield much information (I'll no doubt be eating my words if the first response is a link to a thread with all of the answers).

I'm looking into the 1178 circuit with a vague hope of eventually building one. The output transformers are model 16-12416, which seem to appear in a few Urei designs, but for which I cannot seem to find any useful specs. I saw it stated somewhere that these are 1:2 step-up transformers, while other conversations (which never seem to directly address this transformer by model) seem to suggest 1:1. There were a handful listed on Reverb a couple months ago, which have now dwindled to one. That's about all I've been able to find.

Anybody have any information on these? And does anyone know if there exist any good drop-in replacements?

 

[JMan]

Just giving this a bump. Anyone have any knowledge or know of any resources? For what doesn’t seem to be a particularly obscure piece of iron, it sure is tough to scrounge up anything about it…

 

[dmp]

I just looked at the manual quickly and am posting the important parts (you should do this in your original question and you'll get better replies).
In section 4.5 Line Amplifier it says the output transformer adds 3dB gain into a 600 ohm load. Therefore it is not a 1:2 transformer, it is 1.41, or 300:600 ohms. The low phase shift just means it is a high quality transformer that has excellent bandwidth.
The schematic tells you it is a simple primary:secondary transformer, no center taps or additional windings.

 

[JMan]

Thanks, @dmp ! I feel silly that I didn’t put that together from the section of the manual that you referred to, but I completely overlooked that information.

 

[Whoops]

As far as I know that Output transformer is not available as a replacement.
Maybe you should contact Cinemag and Sowter to see if they have an equivalent transformer.

check out this thread:

https://groupdiy.com/threads/building-a-1178-lookalike-dual-1176-replica-out-of-a-urei-535-eq.68767/