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Re: Olympus LS-14 initial thoughts

Subject: Re: Olympus LS-14 initial thoughts
From: "Avocet" madl74
Date: Sat Jan 5, 2013 9:10 am ((PST))
> I have never understood why folks are using fancy preamps even in
> compination with good recorders such as the SoundDevices 7xx series.
> There must be some kind of a placebo effect that makes them
> believing there was a difference or maybe I'm missing something....

Raimund,

With a pro or semi-pro recorder with matched floating mic inputs,
there should be no need for a preamp. The only exception is if you use
a high quality mixer for its other facilities. What I was discussing
was affordable pocket recorders.

I've tested my SQN mixer using the pile of bedclothes method, and the
mixer noise is well swamped by the (very low) MKH mic noise even with
a 10dB input attenuator. This is a different ball game to depending on
transformerless mic inputs cheek by jowl with noisy digital circuits
in a pocket recorder. However good a pocket digital recorder is, an
external input device feeding into a lime input can be an order of
magnitude quieter.

To get technical, the input noise impedance (optimum for noise) of a
direct solid state input will not match a mic at 150ohms without a
transformer. To get a balanced input, two input preamps are required
connected out of phase, again increasing the total equivlant input
noise. When I get around to it I'll try transformers on my Tascam
DR-100 which is a bit too noisy on its XLR inputs.

David

David Brinicombe
North Devon, UK
Cogito cogito ergo cogito sum - Ambrose Bierce







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