D1000E, Paso 601, D130, D112, M55 HN, MD21 HL, MD211, DP4/L and Pleiades V6

Signal path, setup:


Male singing voice - Mic - Pleiades V6 (140mH primary inductance) - Sony TC-D5 Pro - Sennheiser HD 580


The prefered mics of this test were:


Grampian DP4/L
Sennheiser MD21 HL
AKG D1000 E


The D1000E has an amazing low cut high pass filter implementation. When the filter is not activated the proximity effect is left to be compensated by the input transformer of the V6. The sound is unclear possibly due to overloading of the Magnetec core? Same thing happening with the D130, D112.


It was decided to connect the D112 in parallel with the D1000 in hope that the filter of the latter will affect the former. No success. Big mics worked together with some loss of volume. Interesting way to mix, add is the correct term.


When the D1000E filter is on at the position S, it is a very clear sound. An exceptional directional mic. Perhaps it is worth studying this filter and possibly applying it externally to other mics such as Unidyne III, MD441 U3, D112 etc. The schematic shows a resistor is series with an inductor for position M. A resistor is series with an inductor capacitor parallel combination. These 2 permutations are connected in turn in parallel to the voice coil.


The Paso 601 had a nice bass as proximity seems to be somehow compensated by the placing of the membrane reasonance at a higher frequency. But the D1000 has much more HF detail and overall sensitivity.


The M55 has a nice sound with less HF. Needs a special inductance of inout transformer. 140mH is too low and the mic sounds thin. Using its internal transformer connected to the grid of EF183 the sound was big but there was more treble reduction.


The MD211 sounded full and treble extended with the Semmehsier TM513 step up cable transformer. The bass was somehow excessive as this trasformer has a high input inductance, 2H. Of course 140mH is too low too for this mic and it sounds thin.


The Grampian as usual excelled connected to 140mH as it is 25Ω and a great mic. Great bass, mid and treble detail.


The Sennheiser MD21 HL is great too. The most extended response on bass and treble. It may be too much for a soft singing voice. As a soft singing voice already has a great content of lows and highs. This mic has an amazing pop, air blast, sibilant problem rejection.