I did some blind A/B testing of the 744T's
internal pre and an MP2 when I first got my 744T
years back thinking I finally had a good way be
to compare/hear the much discussed "warmer,
fuller" transformer sound of the MP2. I tried all
the mics I had. I guessed wrong over 60% of the
time which confirmed that I have much less
discriminatory hearing than pros.
Given the huge range of real world of monitoring
options people are using, if any improvement is
not readily apparent, by ear, with good
monitoring, I relegate it as insignificant. This
turns out to be good as there's never seems to be
enough money for good mics. Rob D.
=3D =3D =3D =3D
At 6:02 PM +0000 3/17/09, oryoki2000 wrote:
>Sound Devices recorders (702, 722, 744t, and so
>on) are excellent field recorders by any
>criterion. They're also expensive. Hoping to
>find a less costly alternative, I compared the
>preamp of the 702 recorder ($1875 USD) to the
>Sound Devices MixPre preamp ($665 USD) using
>Sound Devices' published specifications.
>
>My conclusion: Compared to the MixPre, the 702
>provides small improvements in most categories.
>I have attached the comparison below.
>
>Whether the 702's performance improvements will
>be audible in a recording made in the field is
>another matter. If you have used the MixPre (or
>its predecessor, the MP-2) and a 7xx recorder,
>please tell me about your experiences! Thanks.
>
>--oryoki
>
>-----------
>Specifications from the Sound Devices web pages
><http://www.sounddevices.com>http://www.sounddevices.com
>-----------
>
>702 Dynamic Range
>114 dB, A-weighted bandwidth
>110 dB, 20 Hz =96 22 kHz bandwidth
>
>MixPre Dynamic Range:
>110 dB minimum
>
>-----------
>
>702 Frequency Response, Mic or Line:
>10 Hz=9640 kHz, +0.1, -0.5 (gain controls centered), Fs 96 kHz
>
>MixPre Frequency Response:
>20 Hz - 30 kHz, +0.1, -0.5 dB; -1 dB at 5 Hz & 50 kHz
>(relative to 1 kHz with 150 ohm source, gain controls set at 50%)
>
>-----------
>
>702 Equivalent Input Noise:
>-128 dBu max (-130 dBV), 150 ohm source, 20 Hz=9620 kHz BW
>flat filter, gain fully up
>
>MixPre Equivalent Input Noise:
>-126 dBu (-128 dBV) maximum (150 ohm source,
>flat weighting, 22 - 22 kHz bandwidth, gain
>control set at 50% or higher, phantom power off)
>
>-----------
>
>702 THD + Noise:
>Mic: 0.004% max (1 kHz, 22 Hz=9622 kHz BW, gain
>control down, -15 dBu input); Line: 0.004% max
>(1 kHz, 22 Hz=9622 kHz BW, gain control down, +16
>dBu input)
>
>MixPre THD + Noise:
>0.05% maximum (from 60 Hz to 22 kHz @ +4 dBu
>output level, 22 Hz - 22 kHz filter bandwidth,
>gain control at 50%, phantom off)
>
>-----------
>
>702 Gain: (input dBu to -20 dBFS)
>mic (normal gain mode):
>25 to 70 dB; mic (low gain mode):
>10 to 55 dB;
>line: -6 to 18 dB, 0.1 dB increments
>
>MixPre Gain:
>LINE output 66 dB
>TAPE output 56 dB
>
>-----------
>
>702 Input Clipping Level:
>Mic input: -5 dBu minimum (normal gain mode, gain control fully down);
>mic input: +10 dBu minimum (low gain mode, gain control fully down);
>line input: +26 dBu minimum (gain control fully down)
>
>MixPre Input Clipping Level:
>-10 dBu minimum
>
>-----------
>
>702 High-Pass Filters:
>40, 80, 160, 240 Hz @ 12/18/24 dB/oct (all menu selectable)
>
>MixPre High-Pass Filters:
>80 Hz or 160 Hz (switch selectable), 6 dB per octave
>
>-----------
>
>702 Mic Powering:
>48 V phantom through 6.8k resistors, 10 mA per mic available,
>Each XLR selectable, mic or line input
>
>MixPre Phantom Power:
>48 V through 6.8k resistors or 15 V through 680
>ohm resistors (switch selectable)
>
>-----------
>
>702 Mic Input Limiters:
>analog (pre-A/D converter), dual-stage optocoupler and FET,
>-4 dBFS threshold, 20:1 limiting ratio, 5 mS attack time, 200 mS release t=
ime
>
>MixPre Limiter:
>Thresholds adjustable per channel from -10 dBu
>to +18 dBu, 10:1 limiting ratio,
>5 mS attack time, 100 mS release time, Dual mono or stereo linked
>
>-----------
>
>702 Analog Line Output Clipping Level:
>+24 dBu minimum, 10k ohm load
>Attenuation & Resolution 0 to 40 dB, 1 dB increments
>
>MixPre Output Clipping Level (Line):
>+22 dBu minimum with 100k ohm load, +20 dBu minimum with 600 ohm load
>
>MixPre Output Clipping Level (Tape):
>+11 dBu (2.75 V RMS) minimum with 100k ohm load
>
--
|