That would work beautifully! But it doesn’t need to be autoformer… Easiest would be 1:2 transformer, and if you ever wanted to wire it as balanced XLR in the future, that would be very easy.
Lots of choice. Also, adding a transformer does something magical to the sound. Hard to describe, but it’s absolutely there. I love it, very beautiful.
Lots of choice. Also, adding a transformer does something magical to the sound. Hard to describe, but it’s absolutely there. I love it, very beautiful.
thanks for reminding me of this autoformer, subs ZM thread long time ago but still never purchased any maybe due to the cost hahaha. another 30% for customs fee will end around 650 eur which is alot for me
anyway i find this local made LoT which will cost me around 140usd per pair, stated it can be configured from 1:2 up to 1:5
any input which gain should I choose? will 1:5 become too much gain or just keep 1:2?
anyway i find this local made LoT which will cost me around 140usd per pair, stated it can be configured from 1:2 up to 1:5
any input which gain should I choose? will 1:5 become too much gain or just keep 1:2?
The impedance reflected back to the buffer by the load will be the load impedance divided the square of the turns ratio. So if your load is 10k ohms and you use the 1:5 ratio, the load on the B1 will be 400 ohms. At 1:2 it will be 2500 ohms. The output Z of a B1 buffer is about 150 ohms if memory serves, but the standard schematic shows a 1k resistor between the output cap and the output. ZM once suggested removing or jumpering that output resistor when presenting the B1 with a heavier than normal load like from an line transformer.
more info about inductances of thingie?
from numbers and winding arrangement, configurable ( in pure transformer mode) as 10K: 300 (which is 5.77:1 voltage vise) and 10K:1200 (which is 2.88:1 voltage wise)
late in my head, so I can't fathom proper ratios for autoformer config now
from numbers and winding arrangement, configurable ( in pure transformer mode) as 10K: 300 (which is 5.77:1 voltage vise) and 10K:1200 (which is 2.88:1 voltage wise)
late in my head, so I can't fathom proper ratios for autoformer config now
ok no info about inductance
anyhow - confirm what exactly you bought, so we can go slightly deeper in options and - clarify what you mean by "B1-LIT-B1"?
Seems to me if you want a really good B1 type pre with gain then just get the Iron Pre. It does everything and does it very well. I have one.
But I also wanted more gain in my home brew B1 Rev 2 so just added a top quality op-amp (LM4562) gain stage in front of the buffer stage. It works and sounds great plus allows fine control of the gain amount and input Z and there are no reactance concerns. .... and its costs much less than transformers. That's just my 2 cents. You have options available and they are all good.
But I also wanted more gain in my home brew B1 Rev 2 so just added a top quality op-amp (LM4562) gain stage in front of the buffer stage. It works and sounds great plus allows fine control of the gain amount and input Z and there are no reactance concerns. .... and its costs much less than transformers. That's just my 2 cents. You have options available and they are all good.
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it's really useful if you respond to questions ....... I'm still not sure that you bought exact xformers shown in post #522, and list shown in post #525 is general one .....
when you confirm xformers you're having in your hands, I can go in simple calc exercise, to see what you have with (my preferred) autoformer arrangement
ok, to paraphrase my self - above written what you get with regular xformer arrangement
if you connect it as autoformer, you'll get 6.77V/V or 3.88V/V gain
say that B1 is having Rout in range of 40R, so here is what you have with B1 followed with autoformer (without second B1 in cascade, after autoformer)
in first case Rout should be 6.77^2*40R
in second case 3.88^2*40R
that, if you buy xformer shown on pic in #522
