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Group Purchase for CineMag Input Transformers

For those who would prefer to opt for the CineMag CMMI-15/15B over the more expensive Jensen JT-11P-1, the $38.26 price I gave in the Jensen thread is for 11-49 pieces. Since I could use another one, I'll buy the odd man out which means just 10 pieces for the group buy.

se


Interest shown for the CMMI-15/15B :

Dr. Strangelove3 : 2
Algar emi : 2
ble0t : 2
Steve Eddy : 2
Sy : 2
motherone : 2
Michi124 : 2
Andrew T : 6 (tentative)
Bas Horneman : 4
acliao : 2
pkpickard : 2
pekka : 2
jrd : 2
leadbelly : 2
jaap : 2


Total : 36
 
ble0t said:
I'd rather do two of these since they're cheaper ;)

No no. Read my lips. That's "less expensive." :)

BTW, is it necessary to add an op-amp gain stage onto the output side of the transformer? I've seen that in both the Cinemag and Jensen datasheets...is it just to lower the impedance?

No, there's no need for an opamp gain stage on the output. But it's going to have to be feeding some sort of high impedance input. How are you planning on using these?

se
 
No no. Read my lips. That's "less expensive." :)

I meant it in a monetary sense only ;)

No, there's no need for an opamp gain stage on the output. But it's going to have to be feeding some sort of high impedance input. How are you planning on using these?

I was going to use them at the front end of my upcoming leach amp to allow for balanced input. I think pooge posted about some circuit modifications that would need to be made, but I can't remember where that post was...
 
ble0t said:
I meant it in a monetary sense only ;)

Well yeah, but "less expensive" is a monetary sense only too. :)

I was going to use them at the front end of my upcoming leach amp to allow for balanced input.

Ah, ok.

By the way, unless you already have a balanced output you want to feed it, keep in mind that with a good input transformer, common-mode noise rejection is very high whether you're feeding it from a balanced source or an unbalanced source.

In any case, you would just use the transformer directly with the amp's input without any intervening opamp circuit.

I think pooge posted about some circuit modifications that would need to be made, but I can't remember where that post was...

Can't help ya there, sorry. :(

se