It is possible to have possibly the least noisy and best quality recordings on the planet with the SONY WM series portable cassette recorders and Pleiades K117 pre preamplifiers.
As we now know after experience with recording to digital recorders, hiss is usually not coming from tape but from preamplifiers and recording environment.
Any world class microphone such as MD441, MD421, MD21 can be connected to the Pleiades inline female to male XLR input transformer. Inside is a Magnetec 073 state of the Art Nanocrystalinne Nanoperm magnetic toroidal core. Instructions to wind this as well as making the Pleiades K117 is given on earlier euroelectron posts.
The number of primary turns can be chosen to reduce unnatural bass and compensate for the proximity effect, Fletcher Munson equal loudness curves and the voice effort effect well known to cinematographers.
So the input is low impedance and purely balanced. After the noisyless and stepped up voltage from the Pleiades transformer the secondary which is high impedance (like a condenser capsule) is now connected to the JFET Pleiades K117 pre preamplifier (like a condenser or electret inhouse mic preamplifier) which is housed inside the female XLR itself to save space.
The Pleiades K117 pre pre is possibly the simplest preamplifier on the planet using only a K117 JFET and an aproximately 200Ω source resistor. The gate is the input. The source of the K117 is connected to ground through the 200Ω resistor. The drain is connected directly to the SONY WM in the same way as it is done to an iPad one iPhone. The WM will treat the Pleiades K117 (one for each channel) as electret and will power the K117 JFET through its internal resistors (one for each channel) which act as drain load resistors.
If a high impedance microphone is used it can be connected directly to the Pleiades K117 without the need of the input transformer saving even more space. Examples are the
Shure Unidyne III, MD421 HN, MD21 HL which have their own input step up transformers for high impedance and output, inside them.
Good news is that the Pleiades K117 can fit inside the Amphenol or the Cannon connector for even more space saving.
So practically one is left with 2 top quality microphones intact, and the SONY WM recording at world class quality with no noise.
A disadvantage is that proximity compensation is not possible unless you connect an external Pleiades filter to the low impedance output (an inductor in parallel with the low impedance output of the mic). Omnidirectional microphones need much less compensation.
A secret of great recording is for musicians to play softly. An obvious example is Kind of Blue - Miles Davis. (See also next euroelectron post).
Have you wandered that hiss is not coming from tape but from preamplifiers?
Playing softly produces an acoustic (and then electric signal) that has peaks close to the average level. This allows to further modulate a magnetic tape process which is peak forgiving anyway. And you achieve a loud recording. This shows when you transfer to digital.
Less s is more. The softer you play the louder and fuller it will sound.
But musicians playing softly means we need the best pre preampifiers and a very quiet recording location.
Pleiades preamplifiers are attempts to make the quietest possible preamplifier with the least possible components, near to 0! So the magic of music goes on.
As we now know after experience with recording to digital recorders, hiss is usually not coming from tape but from preamplifiers and recording environment.
Any world class microphone such as MD441, MD421, MD21 can be connected to the Pleiades inline female to male XLR input transformer. Inside is a Magnetec 073 state of the Art Nanocrystalinne Nanoperm magnetic toroidal core. Instructions to wind this as well as making the Pleiades K117 is given on earlier euroelectron posts.
The number of primary turns can be chosen to reduce unnatural bass and compensate for the proximity effect, Fletcher Munson equal loudness curves and the voice effort effect well known to cinematographers.
So the input is low impedance and purely balanced. After the noisyless and stepped up voltage from the Pleiades transformer the secondary which is high impedance (like a condenser capsule) is now connected to the JFET Pleiades K117 pre preamplifier (like a condenser or electret inhouse mic preamplifier) which is housed inside the female XLR itself to save space.
The Pleiades K117 pre pre is possibly the simplest preamplifier on the planet using only a K117 JFET and an aproximately 200Ω source resistor. The gate is the input. The source of the K117 is connected to ground through the 200Ω resistor. The drain is connected directly to the SONY WM in the same way as it is done to an iPad one iPhone. The WM will treat the Pleiades K117 (one for each channel) as electret and will power the K117 JFET through its internal resistors (one for each channel) which act as drain load resistors.
If a high impedance microphone is used it can be connected directly to the Pleiades K117 without the need of the input transformer saving even more space. Examples are the
Shure Unidyne III, MD421 HN, MD21 HL which have their own input step up transformers for high impedance and output, inside them.
Good news is that the Pleiades K117 can fit inside the Amphenol or the Cannon connector for even more space saving.
So practically one is left with 2 top quality microphones intact, and the SONY WM recording at world class quality with no noise.
A disadvantage is that proximity compensation is not possible unless you connect an external Pleiades filter to the low impedance output (an inductor in parallel with the low impedance output of the mic). Omnidirectional microphones need much less compensation.
A secret of great recording is for musicians to play softly. An obvious example is Kind of Blue - Miles Davis. (See also next euroelectron post).
Have you wandered that hiss is not coming from tape but from preamplifiers?
Playing softly produces an acoustic (and then electric signal) that has peaks close to the average level. This allows to further modulate a magnetic tape process which is peak forgiving anyway. And you achieve a loud recording. This shows when you transfer to digital.
Less s is more. The softer you play the louder and fuller it will sound.
But musicians playing softly means we need the best pre preampifiers and a very quiet recording location.
Pleiades preamplifiers are attempts to make the quietest possible preamplifier with the least possible components, near to 0! So the magic of music goes on.
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