Eros on it's way!

Jay · 1760

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Offline Jay

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on: April 11, 2016, 06:24:43 PM
My new Eros is due in 3 days!  I have the parts I need for my step up transformer.  I have a pair of cinemag 1254's.  If I use the 1:20 winding, the cartridge load will be 117.7 ohms with no resister.  That's pretty close to my initial target of 100 ohms, but will add up to 76 db of gain (50 for the Eros plus 26 for the SUT).  If I use the 1:10 winding, there is less risk of noise or distortion, but 470 ohms will be reflected.  I'd need a 12.7k resistor to bring the load to 100 ohms.

Is either of these options is likely to be more satisfactory?  Based on Joshua's comments in a different thread, I'm leaning toward the 1:20 with no resistor. (  http://bottlehead.com/smf/index.php?topic=8998.0 )

Thanks all
Jay

Jay L.


Offline Doc B.

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Reply #1 on: April 12, 2016, 05:00:06 AM
With no info about the nominal output level of the cartridge given, I'll suggest starting with 1:20 and see how it works.

Dan "Doc B." Schmalle
President For Life
Bottlehead Corp.


Offline Jay

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Reply #2 on: April 12, 2016, 06:46:25 AM
Thanks Doc.  My cart has a 5 ohm internal resistance and .3mv output.  Mfg recommends >20 ohm load.  My understanding of the math says start with 50 to 100 ohms.  my current ss phono pre is set at 100 ohm and seems to have good balance between bass and treble.

Jay L.