Sunfire Theater Grand IV AV Preamp/Processor/Tuner

by | Nov 11, 2005 | Component Reviews | 0 comments

Sunfire Theater Grand IV AV

MSRP: $4000

Specs and Features:

  • Auto signal-sensing input switching – automatically turns the unit on, selects your source and surround mode
  • 7.1 Channel Dolby Pro Logic IIx, Dolby Digital,
    Dolby Digital EX, DTS, DTS-ES and DTS Neo:6 decoding, plus Side-Axis
    outputs for 9.1 channels playback
  • Bob Carver’s Sonic Holography Imaging in noise-free DSP for the soundstage enhancement of two-channel sources
  • Second zone plays sources independent of the main zone
  • Full-time digital downmix provides accurate
    two-channel output for tape recording, digital outputs, and second zone
    from multichannel digital sources
  • Nine channel (user settable) “PARTY” mode engages all speakers from any two channel source
  • Direct two-channel analog bypass mode
  • Preprogrammed and learning remote control with LCD display
  • Bob Carver’s Dynamic Tuner Noise Reduction for dramatically improved clarity of weak FM stations
  • Simulated surround mode converts stereo inputs into five or seven channels of output
  • FM/AM tuner with Bob Carver’s Dynamic Noise Reduction circuit and 40 presets
  • DSP tone controls
  • Three 100MHz+ HDTV compatible wide-bandwidth component video inputs and two outputs
  • Format conversion between S-VHS, component and composite video
  • Six audio/video inputs, each with audio, S-video and composite video
  • Three audio-only inputs, including Moving Magnet Phono input
  • Eight analog audio inputs for DVD-A, SACD
  • Digital audio (S/PDIF) inputs for six sources: four coax or optical, plus two coax only
  • Coaxial and optical digital (S/PDIF) outputs provide two-channel digital downmix from 5.1 sources
  • Balanced XLR outputs for primary 7.1 channels
  • Four subwoofer outputs
  • Side-axis side speaker outputs for completely enveloping soundstage (total of 9.1 channels!)
  • Comprehensive all-digital bass manager with crossover frequencies of 40 to 160Hz
  • 24-bit A-to-D converter and 24-bit/192kHz Multibit D-to-A converters for the ultimate in sound quality
  • Separate trigger outputs and infrared inputs for both zones
  • FLASH memory upgradable just by playing a CD-ROM
  • IEEE-1394 (Firewire™) port for future expansion
  • Two-year parts and labor warranty


I’ve lived with the Sunfire Theater Grand III for a few years now, so
was quite familiar with most of this new version.  The main
attributes that warrant the price increase of $500 on this new model
are the addition of Dolby Pro Logic IIx, which creates not only center
and surround channels but also one or two center rear channels. 
Few DVDs offer this option on their soundtracks and the matrixed option
doesn’t make much difference to my taste, but if you have speakers and
amps and don’t mind a couple of speakers which might end up right in
the center of the entrance to your listening room, more power to you.
The other new development is the conversion within the Theater Grand of
both composite and S-Video inputs to the higher-quality component
video.  Since I avoid running my video connections thru the
Theater Grand IV this isn’t a valuable feature for me but could well be
for those with a variety of different video inputs with their various
audio companions.

The Theater Grand now comes in a Platinum finish as well as the
familiar audio black, and I asked for that. It makes it less invisible
in my equipment cabinet and the “landing lights” LEDs on the front of
the unit don’t stand out quite a strongly as they did with the black
chassis.  Also, there is now a dimmer control for the
lights.  The physical dimensions have little changed, and the
forest of inputs and outputs on the rear of the unit are basically the
same except for a switch of the AM and FM antenna connections at the
left rear.  The rounded corners on the cabinet look great and
stand out more prominently with the platinum color.  The main
observable change on the front panel is that the squarish rectangular
blue-type display in the top center of the preamp has been replaced
with a more elliptical rectangle.

Hookups and Options

There are plenty of options on the rear panel of the Theater
Grand.  If you are a stickler for balanced connections between
your preamp and amps, you will appreciate the balanced XLR sockets for
the main 7.1 channel outputs. There are not just one but four subwoofer
outputs, and the trigger option operates not just for the main room but
also for the Zone 2 areas.  And Sunfire is evidently still unique
in the high end multichannel preamp field in allowing for Flash
upgrades by simply playing an update CD which they send you rather than
hooking up the RS 232 port on the back, as with competing AV preamps.

All the various decoding options are present in the Theater Grand IV
except HDCD and Circle Surround, which are both of limited interest.
All the various adjustments for both Pro Logic IIx and DTS Neo: 6 are
included in the on-screen settings. Also of course the adjustments for
the speaker distances, whether large or small, and the bass management
settings. The range of the crossovers are from 40Hz to 160Hz in 10Hz
increments.  A disappointment is that – like most such processors
– these adjustments are bypassed completely when listening to “source
direct” or the 8-channel inputs. So you had better have your surround
speakers all set up at roughly the same distance from your sweet spot
as your front speakers or listening to multichannel SACD and DVD-A will
be compromised.

The FM reception of the Theater Grand IV is excellent. There’s no way
to turn off the Carver noise reduction built into the FM section, but
it’s very effective on poorly-received stations.  AM is about as
poor as in most tuners today.  You can set the tuner section for
up to 40 different stations and the long row of  “landing lights”
on the unit’s faceplate are also buttons to select ten of the stations.
(A bit of overkill if you ask me.) The remote is a rebranded
TheaterMaster universal remote and can be taught to control up to ten
different components.

Even if you eschew the video section of the T.G. IV, you will want to
run at least an S-Video or composite cable from its main video output
to one input on your display for the On Screen Display.  It also
comes up on the small blue display on the faceplate, but only one
function at a time, and can be confusing to operate.  The Guide
and Exit buttons on the remote bring up the OSD on your screen. The
extensive menu permits adjustments of Trims, Modes, Tone, Inputs,
Settings of the Zones, speaker adjustments, video and OSD, software
settings etc.  The proper selection of Zone 2 for feeding a signal
to other rooms of your house is a bit frustrating but careful following
of the manual procedure will eventually reward you.  It does have
the ability to play a different source in Zone 2 than is playing in
Zone 1.  This option is disabled as the unit comes from the
factory and must be enabled to feed a signal at all.  You can also
adjust the volume level of the various sources, their maximum volume,
and what source will be the default when using a particular input.

A very useful function is the Video Delay setting. This actually acts
on the audio signal, not the video, allowing delaying the sound in 1 ms
steps to match the delayed video on many broadcast programs due to
extensive processing of the video image.  Once selected, you can
watch the lip sync of images on your screen while adjusting the audio
delay using the joystick on the remote. (The next step would be to put
this feature directly on a remote button to be accessed instantly, as
one manufacturer has already done.) The Source Direct setting bypasses
every bit of the digital processing in the T.G. IV and is best for
completely analog sources such as stereo vinyl or exceptionally purist
two-channel CDs or SACDs. The latest incarnation of Bob Carver’s Sonic
Holography circuit is realized in the digital domain here, and it can
be used with any two-channel source if you are sitting precisely in
your sweet spot equidistant from your two frontal speakers. I found it
similar in effect to the past analog iteration of the circuit – very
subtle on most recordings but on a few adding an exceptionally
realistic depth and spatiality.  While it can also be used on the
front L & R channels while in multichannel mode, I found the effect
completely lost in that situation.

More effective than Sonic Holography is the latest version of Pro Logic
II.  It creates extremely effective surround and center channels
on nearly all two channel recordings, often rivaling the effect on
classical and jazz that one hears with discrete multichannel
recordings.  If the two-channel recording preserves a great deal
of the L-R information, the level on the surrounds may be so high you
will need to reduce them either with the OSD or by using the remote’s
joystick on the REAR- option.  This is especially true of binaural
recordings, which create a very convincing surround field using Pro
Logic IIx.  Matrix Dolby Surround CDs also work very well with Pro
Logic IIx.  My idea of audiophile nirvana is playing the best of
my many audiophile direct discs – especially those cut at 45 rpm – thru
the Pro Logic IIx decoding for a fabulous surround field.


Any gripes?  Well, just a few: The automatic source select doesn’t
always work, and is not designed to work with “source direct” or
8-channel analog inputs. (But it is nice to turn it on prior to my wife
watching a DVD on her own – then it switches instantly to the DVD
player.) I was hoping one of the new features of the T.G. IV vs. the
III would be a logical circuit for the Side Axis speakers – namely a
matrix of the difference signal between the left front and the left
surround on one side and the two rights on the other.  Instead it
continues as a mix of 80%  of the R channel (on the R) plus 20% of
the L channel and vice versa on the L.

The Phono input is a thoughtful inclusion but it is only moving magnet
and many of us who haven’t given up on vinyl by any means have moving
coil cartridges requiring more phono preamp power than the T.G. IV
offers.  Fine, we can use the Tape or DAT inputs instead. 
The T.G. IV selects the source which is turned on and ignores the other
tape deck. But most of us with a solid state outboard phono preamp
leave it on all the time, so the tape source plugged into the other
input won’t be selected.
In my case I require an outboard jerry-rigged Switchcraft switch to
switch between MC and tape source. (I have four, including a Beta Hi-Fi
– requiring a RussSound five-input switch for that.)  My last
gripe is that while many inputs on the preamp accept both analog and
digital connections from the same source, when both are plugged in the
digital always takes precedence.  I wish there was a Menu option
to choose between them to do comparisons.

Wrap Up

I also have a gripe about the copy on the Sunfire web page on the T.G.
IV: “If your eyes get tired, the Theater Grand also includes…” and
then it mentions the analog eight-channel inputs, “source direct,”
phono input and tuner.  Well, don’t get the idea from this that
the T.G. IV is primarily a home theater/video component with high end
audio considerations a second thought.  It is also designed as a
perfectionist stereo and multichannel preamp.  All the digital
processing circuits can be disabled using the eight-channel and source
direct settings, and its ability to generate a clean and transparent
frontal sonic image or an enveloping sense of spatial surround are
truly impressive.  

Even with the full-blown digital processing while viewing a DTS or
Dolby soundtrack DVD, the T.G. IV still sounds impressive.  I’m
keeping mine and mating it with tube monoblocks on the front channels,
which I find a perfect sonic marriage feeding my Von Schwiekert
VR-2s.  However, I still have solid state amps on the matching
surround channels and the sound is just about as sweet and musical as
on the fronts.  The T.G. IV doesn’t suffer from a bit of the
hardened, steely sound quality of some multichannel preamps and

– John Sunier

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