<<Listening back to some recent recordings, I am noticing hiss. The
recordings were taken on a pond where it was very very quiet. The rig
I am using is an MKH30/40 pair -> Fostex FR2LE. No preamp other than
the one built into the FR2LE. The trim and the input knobs
on the FR2LE were set to their maximums to get a decent saturation
(which is probably my first clue). Maxing out these settings were also
necessary in louder environments.
So here is the question(s): Is this hiss generated by the mics, the
preamps, or both? >>
It would be a combination of both. All electronic circuits generate
some degree of noise. A noisier circuit will largely mask the noise
of a quieter in-line circuit. Usually mics are the weak link, but to
improve upon the Sennheisers would require going to a much more
unwieldy large diaphragm design.
<<Would adding a good preamp to get a better
saturation help reduce the affects of this hiss?>>
Maybe, although I'm skeptical. The weak point, IMO, of the Fostex
FR2LE is the lack of access to the digital signal buss. If one could
bypass the built-in analog stage by using an external preamp/
converter, like the Grace Lunatec, you would achieve quieter results.
However, such a recorder would compete directly with Fostex's higher
priced pro units. Adding a higher end external preamp to the FR2LE
would simply add the better unit's noise to the existing noise of the
Fostex, with the possible exception of (A) in line input mode, the
Fostex input electronics may be quieter than the mic preamps (though
many preamps in consumer level gear merely pad down the mic preamp to
achieve line level,) or (B) the noise characteristics of the Fostex
mic pre may be non-linear, resulting in a big increase in noise as
you approach the highest gain setting. Every preamp design is
slightly different, but it is fairly common with less expensive
designs that the last 3 db of gain provides more than 3 db additional
noise.
<<I do not have other gear to do any mashup testing, so any advice from
those with more experience would be greatly appreciated. My hunch is
that the FR2LE preamps are either not clean enough or are not powerful
enough when using an MKH pair considering all the postings (and specs)
I have seen touting the low self noise of the mics.>>
I would suspect that, at its price point, the Fostex mic pres are the
primary noise source, and, at its market point, you don't have any
real workaround.
Scott Fraser
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