Turtlerock Forum

I got some transformers from Rick, in a trade.

i was just playing with them, with the preamps I am building and trying to decide which ones to use with certain chips etc.. when I had a thought.

Anything wrong with this thought...?

Instead of hard wiring the transformers into the preamps. Box them up with TRS ins and Outs on them and use them in a patch bay.

Because I might end up with a mixture of preamp ICs this way, I could mix and match the different sonic color easily, over time I might end up with combinations I like, then I could permanently mount them if I wish.


Supplementary question Mr Speaker...


Imagine a center tapped primary.

The center tap is a white wire, the outer wires are Yellow and Blue.

I measure 25 Ohms across Yellow and Blue. I measure 11 Ohms between the White and Yellow and 11 Ohms between the White and Blue.

Can I wire Blue and Yellow together and then use the White wire as the other side of the primary to achieve 11 Ohms ?, and if so, does this give me, I dont know if this is the right word... Humbucking noise cancellation on the input?


thanks

Peter

Wiz, you can mount the tranies outside the box, but you're going to need to keep the pre unbalanced so you can patch into the primary side. Might be a pita, might not, depends how much you want to move the pre around etc. You could also mount a few transformers inside the pre with a switch selector ala Shodow Hills, but if they are all the same metal then the difference might be too small to make it worth the hassle?
Cut to the chase, start forging your own alloys and then wind your own trannies. You know you want to.

Chinagraf wrote:Wiz, you can mount the tranies outside the box, but you're going to need to keep the pre unbalanced so you can patch into the primary side. Might be a pita, might not, depends how much you want to move the pre around etc. You could also mount a few transformers inside the pre with a switch selector ala Shodow Hills, but if they are all the same metal then the difference might be too small to make it worth the hassle?
Cut to the chase, start forging your own alloys and then wind your own trannies. You know you want to.

I seriously sat there today and thought "you know, I should look into making my own...."

That's what Rob did for me - a 1 RU - 8 ch Jensen transformer box, TRS in /out, 1:1 & 1:2 switch, earth lift.
Smart move.
Thinking outside the box.

Thanks both of you for replying

Can you twitch the blue and yellow together and drive signal between this and the white? NO.

You don't have to make the preamp unbalanced to put a transformer in front of it. Keep everything balancex and pin1 ground intact.

You won't pass phantom though. ..

Use XLRs....

rob wrote:Can you twitch the blue and yellow together and drive signal between this and the white? NO.

You don't have to make the preamp unbalanced to put a transformer in front of it. Keep everything balancex and pin1 ground intact.

You won't pass phantom though. ..

Use XLRs....

Thank you Rob. Just to clarify these are output transformers... I have phantom taken care of phantom powerd with OEP tranny siting on a go between plus.

There are a few other ways to do this too. You could use a quasi balanced output stage to balance the output for the preamp and then feed that into any transformer. For most transformer "tone" you should load the transformers in different ways using switches to control this and I would use one modern clean sounding transformer and a bunch of old line transformers setup for different ratios and try to get some small core ones too because they will saturate much more than larger units.. If this was in a separate box then you could use it for other scenarios not just your INA preamp.

mylesgm wrote:There are a few other ways to do this too. You could use a quasi balanced output stage to balance the output for the preamp and then feed that into any transformer. For most transformer "tone" you should load the transformers in different ways using switches to control this and I would use one modern clean sounding transformer and a bunch of old line transformers setup for different ratios and try to get some small core ones too because they will saturate much more than larger units.. If this was in a separate box then you could use it for other scenarios not just your INA preamp.

Thanks Myles

I am having a blast with this, surprising how much time it consumes, which atm is actually a good thing.