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Thursday, March 30, 2017

The New VarEQ Phono for 78rpm Records

Hi!

After the last Variable EQ phono stage for 78rpm records I always wanted to build one with switchable LCR EQ. Here it is.






Bernd Hemmen and Wolf von Langa with whom I will set up a system at the upcoming High End show again, came up with the idea to do 78rpm demos similar to the  one at the ETF in Berlin. A good reason to develop a new variable EQ preamp for such an event.




This time with D3a tubes and based on the same fully transformer coupled circuit as my D3a LCR RIAA phono stages.




Only mono this time and with separately adjustable bass turnover frequencies and treble roll off.





The last implementation had too many settings with 12 positions for each. This time I reduced to just 6 settings each.





The two D3a tubes are placed at the front and part of the chokes and transformers of the circuit are placed on top under transformer covers.




The power supply is completely separate:




Visit us at the High End fair and join us for a journey through the history of Jazz on 78rpm!




Best regards


Thomas



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