Navigation Bar

GTP-550 and GTP-600

See related product information.


Adcom's high-end audio heritage is evident in the revolutionary GTP-550 Surround Sound Tuner/Preamplifier. Built with a unique combination of advanced circuitry and ergonomic design, the GTP-550 is the ideal command center for any home theater system.

The GTP-550 is designed with two Dolby Pro Logic® modes: Dolby Pro Logic and Cinema. In the "Cinema" implementation of Dolby Pro Logic the front channels are equalized and diminishing multiple delays are added to the rear channels. This more closely approximates the sound of a large theater.

In the Dolby Pro Logic mode the GTP-550 presents a spatially correct soundstage with precise lateral imaging and front to back depth. This is the second of two preferred modes to properly process Dolby Surround® encoded video soundtracks, a growing number of CDs and even the audio portion of some computer games.

The GTP-550 also includes three Digital Signal Processing modes. These delay modes create psychoacoustically correct environments, from an intimate nightclub to an outdoor stadium, all at the touch of a button. This wide array of delay mode options gives you the power to create custom soundfields for your favorite videos or music events.

The GTP-550's Stadium mode is used for non-Dolby Surround encoded material to recreate a large and acoustically reverberant environment well suited for video sporting events and play back of music events performed in large outdoor arenas. A slight upper midrange frequency emphasis is added to the front channels to enhance intelligibility. Stadium mode is also well suited for playback of older epic movies.

The GTP-550's Concert Hall mode replicates a relatively large indoor performance space. Front channel frequency response is flat for maximum musical clarity while the diminishing multiple rear channel delays first seen in Cinema mode enhance the sense of spaciousness.

In Nightclub mode the GTP-550 synthesizes a smaller and more intimate soundfield ideal for many types of jazz and popular music. Nightclub mode is also a good choice for playback of classic movies with mono soundtracks.

The Five Channel Stereo mode makes full use of a home theater system's speaker complement and is intended primarily to reproduce large scale musical events such as a full orchestra concert or an opera. In addition, the GTP-550 also includes a two-channel stereo mode for true stereo sound.

The lessons learned in the design of Adcom separates directly benefit the GTP-550 as do high-precision electronic parts: Roederstein 1% metal film resistors, the same class "A" biased linear gain amplifiers developed for Adcom's reference class components and an oversized transformer that projects superior soundstaging and imaging

When it comes to FM broadcasts the GTP-550's highly sensitive tuner section delivers the clearest sound the transmitted signal allows. All tuner circuitry is isolated on its own low-loss, epoxy board and constructed with specially crafted RF, IF and multiplex decoding circuits for minimal interference and optimal clarity.

The GTP-550 combines the extensive switching and signal processing capabilities with a rare degree of operational simplicity. Straight-forward design and logical control groupings replace the usual intimidating front panels with often inaccessible and confusing multi-function controls.

All these features are easily operated by the GTP-550's infrared remote for total control from anywhere in the room. And the GTP-550 is fitted with high quality input and output connections for four audio and four video sources. This configuration ensures complete compatibility and flexibility for all your home entertainment needs for years to come.

Adcoms GTP-550 is the clear choice for a unique combination of high-end sound and full featured ease.



The GTP-600 and the GTP-550 share the same operating circuitry and delay mode features. In fact, the internal components (resistors, capacitors, etc.) are almost identical. However the GTP-600 was designed with several upgraded features that create a discernible difference when compared to the GTP-550.

The GTP-600 includes the RC-65 "learning remote" that can be programmed to control up to eight additional audio or video components. The benefit is obvious. Rather than depending on a collection of remote controls, the GTP-600's simplified remote can easily operate an entire audio/video home theater system.

Aiding in this complete control of the components, the GTP-600 includes an on screen display for quick system set up and customized operation. The display shows the selected input, operating mode and delay choices and provides visual feedback to facilitate proper level adjustments.

The GTP-600 also accommodates a wider selection of input and output types by providing a full complement of S-video connectors to supplement the standard composite video jacks. These multi-conductor connections provide high resolution signal transfer for advanced televisions, laserdiscs and VCRs.

In addition, the GTP-600's rear panel RCA audio and video jacks are heavily gold plated to ensure maximum signal transfer and to minimize oxidation. Adcom's GTP-600 offers the highest levels of home theater performance at an equally amazing price.

Adcom GTP-550 and GTP-600 Technical Specifications

Preamplifier Section

Output Impedance
Main Outputs.....475ohms
Tape Outputs.....500ohms

Output level (Rated) .....2.0V

Input impedance.....25kohm

Frequency Response
20Hz to 20kHz +0. -0.5dB

THD+N at Rated Output
20Hz to 20kHz.....<0.005%

IM Distortion (CCIF from 4kHz to 20kHz).....<0.005%

Signal to Noise Ratio (Ref. to 2 volt)
"A" Weighted.....>100dB

Surround Modes

Left, Right, and Center Channel Line Outputs
20Hz to 20kHz.....+0, -0.5dB

THD+N at Rated Output (5 Channel Mode)
20Hz to 20kHz.....>0.005%

THD+N at Rated Output (Dolby Pro Logic Mode)
100Hz to 20kHz.....>0.05%

Signal to Noise Ratio
(All Surround Modes, Ref. to 2 volt)
"A" Weighted.....>95dB

Rear Channel Line Outputs

Frequency Response (5 Channel Mode, No Delay)
20Hz to 20kHz.....+0. -0.5dB

Frequency Response (All Modes With Delay)
20Hz to 7kHz.....+0, -3dB

THD+N at Rated Output (5 Channel Mode, No Delay)
20Hz to 20kHz.....<0.008%

THD+N at Rated Output (All Modes With Delay)

Signal to Noise Ratio (5 Channel Mode, No Delay, Ref. to 2 volt)
"A" Weighted.....>95dB

Signal to Noise Ratio (Ref. to 2 volt)
"A" Weighted.....>70dB

FM Tuner Section

Usable Sensitivity (Mono).....1.2 uV / 13 dBf

Quieting Sensitivity (5OdB)
Mono.....1.7uV / l6dBf
Stereo.....27 uv / 40 dBf

Signal To Noise (65dBf, "A" weighted)

THD+N (1kHz, 65dBf)

Capture Ratio.....1.5dB

Alternate Channel Selectivity (±400kHz).....>75dB

Separation (at 1kHz).....>50dB

Frequency Response (±0.5dB).....30Hz to 15kHz

AM Tuner Section


Selectivity (±10kHz).....> 40dB

Signal To Noise (5mV/m "A" Weighted).....>45dB


Power (available in 220V or 240V on special order)

Chassis Dimensions
4"(102mm) x 17"(432mm) x 11 1/2"(292mm)

Maximum Dimensions
4 1/4"(108mm) x 17"(432mm) x 12 3/4"(324mm)

Weight.....17 lbs. (7.7kg)

Weight, Packed.....20.5 lbs. (10.5kg)

Specifications subject to change without notice.

""Related Products
GFA 7000 Surround Sound Amplifier
GFA 6000 Surround Sound Amplifier
GFA 5800 Amplifier
GFA 5500 Amplifier
GFA 5400 Amplifier
GFA 5300 Amplifier
GFA 5200 Amplifier
GCD 700 CD Player