Quoting from the Sound Professionals product description of the 9V
preamp that goes for $179.00
" Signal to noise ratio: 117 dBu EIN unweighted (quieter than built-
in Walkman preamps) ".
Rob, I am uncertain that condition (2) would be met for me to benefit
using this preamp with the combination of my Edirol R-09 and
Sennheiser ME66 mic, although condition (1) would certainly be met
with the ME66.
The preamp's noise floor is better than the Edirol's ( at -106dBu )
but not better than the ME66 (?). I really don't know what the noise
floor is on the preamp of my Sony Walkman MZ-NF810 recorder, or if my
recordings (noise floor) would improve from purchasing this preamp.
I am a bit confused on comparing the dBu numbers , between recorders
and mics. Thanks in advance for attempting to help straighten me out
on this, and for all the information that you provided.
Regards,
Bill
--- In Rob Danielson <>
wrote:
>
> At 10:13 AM +0000 3/27/08, Philip Tyler wrote:
> >Thanks Rob, I was enquiring as there have been a number of people
> >looking at using external pre-amps in an effort to improve the
> >performance of some of the solid state recorders around or that
they
> >already own. Now if they ever need to replace their recorder with
a
> >new one, and as they are already in possession of a
reasonable 'low
> >noise' mic pre-amp, then it might be more cost effective to buy
one
> >of the less expensive recorders and continue to use their current
> >mic pre-amp
>
> One should be able to determine from ballpark numbers whether a
> particular, lower-cost external pre will improve the performance of
a
> given a recorder/mic combination. The time I ran the numbers with
the
> better external mic pre made by Sound Professionals ( ~$250USD),
the
> answer was, "no."
>
> Two conditions must be met:
>
> (1) The mics must have fairly low self-noise or they will mask the
> the recorder's pre noise anyway. The self-noise of WL183's at
> 22.5dB(A), for example, cannot be improved by using any external
mic
> pre or any "better" recorder. One needs mics with no more than
> 17dB(A) self-noise, something closer to 14dB(A) is safer.
>
> (2) For the noise bed of the external mic pre to be inaudible
> "behind" that of the mics' self-noise, the pre's noise bed needs to
> be 7 to 10 dB(A) lower.
>
> The noise floor of the lower cost external mic pres I've seen are
in
> the -97 to -110 dBu range. This is not low enough to offer
> significant or any improved noise performance. I tend to use the
> noise for a Hi-MD recorders' mic pre, -124dBUv as the maximum
amount
> of noise I can live with in a pre for nature recording.
>
> >So I was thinking that some indication the device delivers on its
> >line-in might prove useful? (I like to keep in mind that there are
a
> >number of enthusiasts that pursue their hobby on a 'tight' budget
> >and it may be that the difference in price between the various
> >recorders can make a big difference to them, also not forgetting
> >size.)
> >
> >I agree that the line-in 'should' produce decent results, but you
> >can never be too sure due to some of the shenanigans some
> >manufacturers get up to :-))
>
>
> I have used the -10dB line inputs on more than 10 MD and DAT
> recorders with a Sound Devices MP-2 as a the mic pre. Its a sad
> over-sight on the part of a manufacturer if a newer recorder does
not
> meet these standards. The -10 line input on Sharp and Sony MD
> recorder will allow one to make great recordings IF a very high
> quality mic pre is used "up front." They are expensive unless one
> makes on DIY. Some may remember that Klas' "on the cheap" external
> mic pre box for unbalanced mics turned out to have more noise than
> that of the Hi-MD's pre. In short, the cheap external pres that say
> they have "low-noise," seem to be referencing higher sound levels
> than those we encounter.
>
> Curiously, all of these new recorders could include mic pres with
> noise performance on par with those in the Hi-MD units. There seems
> to be a lack of awareness and priority on the manufacturers' part,
> not prohibitive production costs. See discussion
>
http://bioacoustics.cse.unsw.edu.au/archives/html/naturerecordists/200
6-07/msg00192.html
> regarding the $4 mic pre ad component, the AK-5356VN-L, used in the
> Hi-MD recorders.
>
> Could we be applying more pressure on these manufacturers to
include
> low-noise, high-gain mic preamps in their recorders? I personally
> think so. The demand seems to be growing rather than diminishing.
>
> >Another thing I am beginning to see as an advantage to these
> >'point-and-shoot' style recorders is the versatility they can
offer.
> >I am a fan of the MZ RH1 due to its small size, but it lacks
> >microphones. So having a device that would allow you to go into
the
> >field which you can use hand held to capture material when you
were
> >not after 'ultimate' quality.. But would then lend itself to being
> >used with an external pre when you wanted to say 'take more care'
> >over what you were recording would seem an ideal tool.
>
> I'm not a fan of built-in X-Y arrays for any sound sources further
> than a few feet away. I'd rather use body-worn mics when hiking and
> be completely hands-free. Why use noisy mics at any time in quiet
> locations? Time and circumstance are too precious.
>
> There was a intriguing quest proposed a while back to liberate the
> omni mic capsules and circuitry from the larger AT-3032 housing and
> re-house them more like Klas's has with the EM-23's,.. Curt Olson
> found he could remove the circuitry from the metal case of the Art
> Phantom III unit ($60USD) without problem. Seems like there's a
neat,
> low-profile. low-noise mic project or product waiting to be made. :-
)
> Rob D.
>
>
> >
> >I for one often go birdwatching, and carrying a tripod and
telescope
> >over my shoulder and a pair of binoculars around my neck, don't
> >fancy adding a recording kit as well as I walk around. But
something
> >like the Olympus which would slip into a shirt pocket by the looks
> >of it would be great. Ideally I would like it to be a dual purpose
> >device so on those occasions when I wanted to record an ambience
> >using low noise microphones it was able to deliver the goods. It
> >would also serve as a memo recorder, which I carry anyway, to
record
> >the birds seen on my wanderings. But at the moment my Sony MZ RH1
is
> >still going strong so I wont be buying anything new for a while :-(
> >
> >Phil
> >
>
>
> --
>
>
>
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