Telefunken Magnetophon Automatic

It sounds very nice even if tape is under modulated.


It has an EF86 front end electron tube. Then an EF83. There is one side of ECC83 that is used to control the gain of the EF83. The other half of ECC83 is the following stage of EF83.


Then there is the magic eye EM83 and the EL95 which is used as bias oscillator.


At the moment there is a listing on eBay.de that shows an advertisement or article with the block diagram.


It sounds very nice.


The schematic can be found by googling Telefunken Magnetophon Automatic and then browsing through the images.


Signal path at recording:


Male or female voice or recorder (flûte a bec) - Grampian ribbon mic 25/50Ω - step up transformer in  Geundig GMD 311 mic? or other British transformer? - Telefunken tonbander automatic (72?) - BASF SM911


Signal path at playback:


BASF SM911 - Uher 4200


The recorder flute recording sounds so real, amazing.


How would this recorder sound with a Pleiades V6 or K117 front end booster amplifier?


Other 74?, 76? Models sound be nice too. On one of the schematics it can be seen that the front end pentode has only 49V at the anode. Pull up bias is from the grid connected to positive cathode with respect to grid by an aprox. 20MΩ resistor. (Cathode is positive wrt grid as it is missing emmited electrons, see also grid leak or Pleiades bias).