SM58, RE-15, 635a, F-96 with Pleiades V5

The input transformer of the Pleiades V5 microphone prepreamplifier has an inductance of only 47mH.


This is to cut bass for flat frequency responce from singer's vocal chords to listener's brain.


It attempts to compensate for the proximity effect, Fletcher-Munson reproduction curves, voice effort production curves.


The SM57 Mexico at 2in sounded correct.


The early vintage RE-15 with low cut, at 2in sounded more focused.


The 635a being an omnidirectional microphone had a more natural sound at 2in. There was more ambience as expected.


The F-96 low impedance sounded very natural at 0in without ,the exaggerated effect and less clear sound, of the other mics at such close distance. At 0in there was no room sound ambience coloring.


For the particular high pitched male singing line chosen the F-96 sounded the most natural to the listener's brain.


Setup, signal path:


Kitchen with tiles halfway up- male singing the ending phrase of Words - Bee Gees - Shure SM58 Mexico or Electro-Voice RE-15 or Electro-Voice 635a or Sony F-96 Low Z - Pleiades V5 prepreamp - Realistic stereo mixer 32-1101A mono mic in - Sennheiser HD 580 precision


Although usually there is induced an electromagnetic noise from the Realistic mixer DC converter to a mic input transformer this was not the case with the Pleiades transformer of the V5. Although this transformer is not even mu-metal shielded there was not any noise, possibly because of the tremendous inductance index of the Magnetec Nanoperm Nanocrystalinne core, the fact that the core is a tape wound ring core and the fact that the winding is electrically or geometrically symmetrical or balanced.


The overall signal to noise ratio of the whole system from vocal chords to listener's brain was very high.


The Pleiades V5 electron tube prepreamp was power supplied by the usual 2 li-ion 3.7V batteries in series for the starved (underheated) heater circuit at 3.7V and the anode supply of 7.4 volts.


References:


Sound Picture Recording and Reproducing Characteristics - Loye, Morgan - Jounal of the Motion Picture Engineers


Pleiades V5 - euroelectron