OEP vs Lundahl transformers in the 1176

mfdu said:

i'm running OEP outputs on one pair, and OEP inputs and outputs on another pair.

i gotta say - the units with OEP trannie i/o are stunning.  smoother than the output only units, and lovely tone whether treating them nice or overdriving the sh*t out of the inputs.
i don't think i need to try the lundahls - everyone says they're so clean . . . too clean?

on the basis of the two trannie i/o units, i'm planning on modding the electrically balanced input units to be switchable from electric in to trannie in (using edcor trannies, i thought - for a bit of extra fun and flavour).
chris.

Click to expand...

G'day Chris.
Did you end up finding a good way to add transformers and switch them in or out of the input section?
I was wondering the same thing!
Cheers,
Evan.
(in Melbourne, also!)

Hi,

Just finished an 1176 d build. First one. I did test the power supply and everything was right before I started filling the rest of the board. I completed the rest checked everything and plugged it in. Light came on and looked ready to go. Took it into the studio to calibrate , powered it up then it died. Light died and now no readings at the +30 - 10 rails. Could it be the transformer and if so, could it be tested at the meter switch without taking everything apart? How would I go about tracking down the problem? Because the light went out would this mean that the problem is likely prior to the pcb board? This is why I am assuming it is the transformer. I know I am getting power to the transformer.
Any help would be appreciated. Thanks

Rich

question about the OEPs

OEP A262A2E
OEP A262A3E

What is the difference between the two described? is one input and one output? (if so which way round?)

Thanks!

you'll find your asnwer if you look at the datasheet for each one: http://www.oep.co.uk/products_listing.php?cat=6&subcat=22&subsubcat=47

the 2E is a 1+1:2+2  while the 3E is a 1+1:6.25K+6.25K, but both primaries are 150R / 300R but higher secondary ratio on the 3E (more set up).
you could use either one for input depending on your needs of the circuit input.  as well either can be used in reverse as an output if you choose to do so (but better options are out there at similar costs).

if you're planning to use it specifically in the G1176 (assumed as it is in the thread title), then you would be using the 2E for both in (IIRC prim in series, sec in parallel) and out (IIRC prim in series, sec in series).
hope this helps.
-grant