Carver CT-29v Tuner/Preamplifier Review

A full-featured audio/video receiver can be a formidably bulky and heavy component, especially if its amplifiers are fairly powerful. Until recently, there has been little interest in separating the component parts of an A/V receiver into low-level (tuner, control, preamp, and surround-sound sections) and power-amplifier units, as is commonly done with stereo components. Only a handful of such products are listed in the latest Stereo Buyer’s Guide. But such a division, exemplified in Carver’s CT-29v tuner/preamplifier, enables you to choose freely among amplifiers with much more power than is practical in even the largest A/V receivers.

The CT-29v heads the lineup of five Carver A/V preamplifiers. It includes Dolby Pro Logic circuits based on digital signal processing (DSP), a Movie Surround mode, Hall 1 and Hall 2 ambience-generation modes for music signals, and a Matrix mode for adding a spatial dimension to monophonic signals. The surround-channel signal delay is adjustable between 0 and 90 milliseconds (ms) except in Dolby Pro Logic, where Dolby Labs restricts it to a range of 15 to 30 ms. Movie Surround provides the same sound-steering processing as Pro Logic but with the full delay range. There is also a three-channel surround mode (Dolby 3 Stereo, labeled “3 Logic”) that enhances stereo signals without requiring surround speakers.

As a preamp and control center the CT-29v is very fully equipped: It has seven audio inputs, three video inputs (for a laserdisc player and two VCR’s, each equipped with both composite- and S-video connectors), and an external-processor loop. The outputs include line-level signals for left and right front speakers, two surround speakers, and a center speaker, as well as S-video and composite-video outputs for video monitor. There is also a line-level subwoofer output with an internal 80-Hz, 18-dB-per-octave crossover and a small rear-panel level control. Tape-recording inputs and outputs permit dubbing any audio source to a tape deck and a video signal to either of two VCR’s (without conversion between composite- and S-video formats, however). Other rear-panel connections enable the CT-29v to control a multiroom audio system— playing a different source in another room with independent volume control—but that requires an optional accessory (the Carver IR-R7 multiroom infrared receiver). The digital frequency-synthesis AM/FM tuner in the CT-29v has auto-scan and manual tuning modes and can store up to thirty preset station frequencies.

The supplied RH-29v infrared handset is of the “learning” variety, designed to memorize the control instructions for a CD player, analog and DCC tape decks, two VCR’s, a TV set, and a laserdisc player. Although its seventy buttons appear formidable, only twenty of them are required to operate the CT-29v. The preamp’s volume knob is motor-driven when operated from the handset.

More than sixty horizontally arrayed signal jacks populate the CT-29v’s rear apron, including separate CATV and FM antenna inputs (both F-connectors) and terminals for an AM antenna. There are two AC outlets, one of them switched. The manual warns that the switched outlet should be used only for line-level components (like tape decks or CD players) and not for a power amplifier, the traditional use for such an outlet. The unswitched outlet can be used for a power amp so long as its power consumption (not the same as its power rating) does not exceed the 100-watt rating of the outlet.

The CT-29v’s front-panel display window shows the usual information: the selected audio source and tuner frequency, signal strength and tuning mode, selected video source, etc. Although this display provides all necessary information on the unit’s operating status, most of it can also be displayed on-screen, over the video program. To the window’s right are two rows of small buttons, each about Vs inch in diameter. The lower row selects the program source, both audio and video, and the upper row selects the audio source for recording as well as the multiroom output. A row of buttons below the display is used for setting the tuner frequency and tuning mode and for storing station frequencies in memory. Ten closely spaced buttons select the memorized stations.

Along the bottom of the panel are four small knobs for tone control and .balance adjustment. One of them, Vocal Zoom, adjusts the center-channel frequency response in the vicinity of 2 kHz in order to modify the sense of presence in vocals or dialogue. To the left are three small buttons (Auto, DSP mode, Delay time) and a row of ten tiny red LED’s. The buttons select the DSP mode and the center-channel mode (normal, wide, or phantom). The power button and headphone jack are also located at the left side of the panel. Plugging a headphone into the jack mutes the main preamp outputs. The right section of the panel contains the large volume knob, which carries a green marker LED, a control that adjusts the volume in the remote room in multiroom mode, and a loudness-compensation button.

We measured the CT-29v’s tuner and basic preamplifier functions in the conventional manner and judged its surround and DSP characteristics by listening to FM broadcasts and CD’s. The preamplifier’s frequency response from its CD inputs to the tape outputs was ruler-flat (within perhaps 0.01 dB) from 200 Hz to 20 kHz and down a mere 0.7 dB at 20 Hz. At the line outputs there was a slightly greater variation, probably caused by the tone-control circuits, but the overall response was still excellent.

Like the basic amplifier frequency response, the RIAA phono equalization was very accurate. The Vocal Zoom control varied the center-channel output at 2 kHz over a +6, -5 dB range at 2 kHz, with negligible effect below 500 or above 5 kHz. The other tone controls’ characteristics were conventional, with a sliding bass turnover frequency and a hinged treble response. Most of the control action took place in the second half of the knob rotation. Following modem research, the loudness compensation boosted only the low frequencies (below about 200 Hz), by a maximum of about 11 dB at reduced volume-control settings.

The CT-29v’s rated maximum output is 7 volts, which is several times what would be needed to drive any consumer power amplifier to its rated output. We were not unduly concerned, then, to find that the preamp output began to clip at 6.5 volts, since its total harmonic distortion plus noise (THD+N) was only about 0.01 percent at a still more than ample 3.5 volts output.

In general, the FM tuner section has adequate, though not outstanding, performance specifications, which our measurements confirmed. The AM tuner’s audio bandwidth was restricted, rolling off to -6 dB at 3.5 kHz and at 45 Hz (which is considerably better than most others we have tested recently). The FM capture ratio was merely adequate, but the AM rejection, image rejection, and selectivity were good. Stereo pilot-carrier leakage into the audio was very low, as was the power-line hum. The stereo FM distortion, though below audibility, was relatively high (distortion was lower in mono).

Although we used the CT-29v only as a stereo tuner/preamplifier, its operation was easy and straightforward. Its compact dimensions (about half the volume of a typical medium-power A/V receiver) and correspondingly manageable weight make it a space-saving alternative to a conventional A/V receiver with comparable features. There are a number of good multichannel power amplifiers on the market that would complement the CT-29v very well. Of course, it could also be used with two or three separate stereo power amplifiers, which could be placed out of sight, leaving this compact and attractive control unit and any source components as the only visible parts of the system. You would, however, have to find a way to switch the power amps on and off independently instead of using the CT-29v’s switched AC outlet.

The CT-29v is not inexpensive, and the necessary complement of power amplifiers would raise the total cost of a system built around it to that of a top-grade A/V receiver, but it is an attractive alternative. Not least among its advantages is a subjective simplicity to its operation that should make it more comfortable for most people to use than many of today’s complex A/V receivers.

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