10368 input transformers

[cornboy7x]

can anyone tell me what these are good for? i have 16 of them, im rebuilding a neotek series III and i want to use them for something. im going to use 31267's to balance the line ins, 1166's or 2567's to balance the group outs. i got some western electric 111c's to balance the mix out and some utc's for the mix insert. but i have no idea what im goign to do with the 10368's. aux returns? mic pres? should i just sell them? if anyone has any good ideas, please let me know...
thanks
eric

[Geoff_T]

Originally Posted by cornboy7x

can anyone tell me what these are good for? i have 16 of them, im rebuilding a neotek series III and i want to use them for something. im going to use 31267's to balance the line ins, 1166's or 2567's to balance the group outs. i got some western electric 111c's to balance the mix out and some utc's for the mix insert. but i have no idea what im goign to do with the 10368's. aux returns? mic pres? should i just sell them? if anyone has any good ideas, please let me know...
thanks
eric

Hi

They are like a 31267 but with a 5Kohm primary instead of 10Kohm.

I have a thread on my site discussing them

http://www.auroraaudio.net/dcforum/DCForumID1/170.html

[cornboy7x]

yea, i saw that and got really excited, but everytime i try to see the replys from you it brings to the home page. i think its a problem with the site. i have the impedence/winding information about them, but to use them for line in its like -9 db loss. any intuitive ideas about wiring them to not get such a loss?

[Geoff_T]

Originally Posted by cornboy7x

yea, i saw that and got really excited, but everytime i try to see the replys from you it brings to the home page. i think its a problem with the site. i have the impedence/winding information about them, but to use them for line in its like -9 db loss. any intuitive ideas about wiring them to not get such a loss?

Hi

I bet you're using a Mac not running IE... that's the usual problem folk have with the site. Use IE or another browser and it ought to work.

Anyway, I've copy/pasted the relevant bits....

***************************************************************

That's a rare transformer... they were only used on passive inputs (like overdub to foldback) on ancient 8014's and consoles of that era.

They are similar to a 31267 but have a 5Kohm series input rather than the 10Kohm of the 31267.

The secondary is identical to the 31267.

So....

Series input (5K) + series output (2K4) = -3dB
Series input (5K) + parallel output (600) = -9dB
Parallel input (1K2) + series output (2K4) = +3dB
Parallel input (1K2) + parallel output (600) = -3dB

So the third one would work with a 183/283 but only give you 3dB lift instead of 6dB.

**************************************************************

The 31267 primary is two 5Kohm windings and the secondary is two 1200 ohm secondaries.

What most folk do is to rotate the transformer configuration and use half of the windings. That gives a 1200 ohm primary and a 5000 ohm secondary - pretty darn close to a 10468.

With your transformer, the ultra rare 10368, you could do as you suggested or, for a bit of flavour, wire it series/series in reverse to get the 2400 ohm primary and either switch resistors or use a pot across the input to vary the input impedance.

That seems to be a "buzz word" these days!

[cornboy7x]

thanks alot. ultra rare you say....does that mean valuable as well? cause if can sell them, id rather do that. you dont know where i could get a bunch of 2567's do you? i need about 24 of them. cant seem to find any.

eric

[Geoff_T]

Originally Posted by cornboy7x

thanks alot. ultra rare you say....does that mean valuable as well? cause if can sell them, id rather do that. you dont know where i could get a bunch of 2567's do you? i need about 24 of them. cant seem to find any.

eric

Hi

Don't book your Hawiian holiday yet. I think they are rare because even Neve saw no point in making them anymore... they never made sense to me, to be frank, as the 10Kohm line matching of the 31267 is more practical.

5K across a 600 ohm source will drop almost 1dB compared to 0.5dB of the 10Kohm 31267.

I've been selling 2567's on EBay for the past month and sold the last one last week. Sorry you missed them.

You could see if Vintech will let you have any... he once advertised he was the USA distributor of Carnhill.

PS Here's a link to Carnhill's 2567 page http://www.b2blocator.co.uk/build/items/00/69/100.html

I must admit that the reference to making these since the 1970's would make Pinnochio's nose grow about 4 feet.

[ljordan]

I bought two of these for DAC differential to to single ended conversion.
In a SACD player.
They are labled 10368/s.
I also notice others for sale marked 10368.
I wonder what the difference is?

Lewis

[Geoff_T]

Originally Posted by ljordan

I bought two of these for DAC differential to to single ended conversion.
In a SACD player.
They are labled 10368/s.
I also notice others for sale marked 10368.
I wonder what the difference is?

Lewis

Hi

To be honest, I don't remember... those transformers are circa 1970.

It may be that one has 10 pins and the other 9. Early transformers had 8 pins for the four windings and pin 6 for grounding the interwinding shield. Later ones had a blank pin 11 added which was a convenient point to anchor the mid point of an unbalanced attenuator on the secondary.

[Jim Williams]

Originally Posted by cornboy7x

can anyone tell me what these are good for? i have 16 of them, im rebuilding a neotek series III and i want to use them for something. im going to use 31267's to balance the line ins, 1166's or 2567's to balance the group outs. i got some western electric 111c's to balance the mix out and some utc's for the mix insert. but i have no idea what im goign to do with the 10368's. aux returns? mic pres? should i just sell them? if anyone has any good ideas, please let me know...
thanks
eric

Put 'em in a box. That way you can use them everywhere, or nowhere. You can then use them, abuse them, feed them backwards, do all kinds of weird stuff that may add the flavors you're looking for. Or not. At least you are in control.

Jim Williams
Audio Upgrades