Adcom GTP-400 Stereo Class A Tuner Preamplifier (1988-89) - Serviced recently by DALAUDIO and found to be in excellent working condition. The manual is available online, bring a USB. Cash Sale No Holds Call or Text for Pick-up.

The GTP 400 received rave reviews in it's day from Stereophile. If you read the review, the cost/benefit was very high for a single ended class A preamp. This unit was designed by Walter Jung who was inducted in the engineering hall of fame in 2002. The unit delivers rich ,transparent, natural clean sound without being sterile. The tuner section is clean and receives local stations and presents a smooth clean signal. Many believe it sounds as good as many single ended preamps costing many times more. If you are looking for good value in an easy to use preamplifier, the GTP-400 might be the best choice.

Consider the original review in 1988 from Stereophile: "... the performance offered is simply superb for anything close to this price [at the time, $350 MSRP], and is always in the service of the music. The GTP-400 allows you to enter the realm of high-end audio without spending a high-end fortune. ...The GTP-400 sets a new standard in the cost vs performance category, and you'll have to spend close to $1000 for a separate pre-amp and tuner in order to move to a higher level of performance."

The technical side - The GTP-400 tuner/preamplifier low-current, low-voltage elements are totally isolated from high-current, high-voltage elements ensuring sonic quality and superior performance. the GTP-400 will drive a single amplifier or two amplifiers in bridge mode. Adcom designers and engineers utilized Class A circuits in the GTP-400's phono and high-level preamp stages. These circuits provide superior resolution and dramatic musicality. Proprietary linear-gain amplifiers in the high level and phono stages operate in full Class A to provide low distortion, low noise and high speed. High accuracy in the RIAA equalization circuit provides superb sound from high output moving coil or moving magnet phono cartridges. A separate recording selector allows listening to one source while recording another. Feedback tone controls and contouring circuits can fine tune your system to room acoustics or individual listening tastes.

The Tuner Section - Quartz referenced and digitally synthesized , the tuner has an accuracy of 0.00025% providing a significant reduction in audible distortion. Eight FM stations and eight AM stations can be programmed for instant retrieval at the touch of a button. Once a station is tuned in, it's locked in without drift. A touch of another button activates the scan mode, up or down. When reception conditions are marginal, a switchable high-blend circuit reduces background noise and fading of FM stereo signals.

Specifications Preamplifier Section
- Total Harmonic Distortion: less than 0,01%
- IM Distortion: 0.005%
- Frequency Response: 20 Hz - 20 kHz ±0,1 dB
- Max. Output Level: better than 8 volts
- Input Sensitivity for .5V Output:
- Phono : 0,8 mV
- High Level : 78 mV
- Signal-to-Noise ratio:
- For .5V Output; Phono : 80 dB
- For 2V Output; High level : better than 95 dB
- Output Impedance: 100 Ω

Specifications Tuner Section
- IHF Sensitivity Mono : 11 dBf
- Signal Strength for -50 dB Quieting
- Mono : 13.5 dBf
- Stereo : 37 dBf
- Capture Ratio: 1.7 dB
- Alternate Channel Selectivity: 75 dB
- Separation at 1 kHz: 50 dB
- Total Harmonic Distortion Stereo at 1 kHz : 0.1%
- Signal-to-Noise Ratio: Mono : 80 dB / Stereo : 75 dB
- Frequency Response: 30 Hz - 15 kHz ±0,5 dB
- Antenna Impedance: 75 Ω or 300 Ω
Voltage: 117 V at 60 Hz
Dimensions (W x H x D) 17" x 3.25 x 12.75
Weight:15 lbs