Warranty, Knoll Systems | Knoll Systems MA252 instruction

Trigger does not 1. Measure trigger voltage with a voltmeter. It

workneeds to be 11-16 volts DC to work (current is about 35mA total per amp). See page 5 for details.

Speaker pops	1. Speaker may need resistor placed across terminal.
when MA252 is	Suggest 2000 ohm 1/4 watt. This discharges the
turned on or off	speaker internal capacitor if it has one.

Warranty

Knoll Systems warrants MA252 amplifiers sold in the USA and Canada by authorized Knoll dealers to be free of defects in materials and workmanship. This warranty extends for three full years from the date of purchase by the original consumer. Any products returned to Knoll Systems and found to be defective by Knoll Systems within the warranty period will be repaired or replaced at Knoll Systems decision, at no charge. Knoll Systems will not be responsible for the actual cost of installation or removal of the product, nor for any incidental or consequential damages. Some states do not allow the exclusion or limitation of incidental or consequential damages, so the above limitation may not apply to you. This warranty gives you specific legal rights. You may have additional legal rights that vary from state to state.

Specifications:


	Line level inputs /outputs	Gold RCA jacks

	Input impedance	50k ohms

	Speaker inputs /outputs	detachable plug

	Output power	50 watts RMS per channel (8 ohms)
	Peak output power	100 watts per channel (8 ohms)

	Ideal impedance	4 - 8 ohms
	Frequency response	10 Hz - 40 kHz +/- 1dB (1w)
	S/N ratio	over 95 dB A weighted (50 watts)
	THD distortion	less than 0.1% 20 Hz to 20 kHz

	IMD distortion	less than 0.01% 60 Hz 7 kHz 4:1 (SMPTE)
	Trigger control	12 VDC 35mA on 3.5mm mono jack

	Dimensions	17" x 3.5" x 11.75" (431.8 x 89 x 298mm)
	Dimensions	17" x 3.5" x 11.75" (431.8 x 89 x 298mm)

	Video trigger	0.5 v p-p minimum

	Power	175 watts at 117 VAC or 230 VAC
	Weight	11 lbs (5 kg)

Note: Specifications subject to change without notice.

Knoll Systems

145 Tyee Drive Point Roberts, WA 98281

12140 Horseshoe Way, Richmond, BC V7A 4V4 Tel: (604) 272 4555, fax (604) 272 5595

Made in Canada

MA252

Stereo Amplifier

Installation Instructions v1.0

Warning: To be installed and/or used in accordance with appropriate electrical codes and regulations.

Description: Designed primarily for custom installations, the MA252 is used to power stereo speakers, usually in a single room. Each channel has a gain control. The MA252 can be turned on and off using the front panel power switch, composite video detection, when music is sensed or the 12 VDC trigger. A special feature of the MA252 is that whole house music from another amplifier can be heard on the speakers connected to the MA252. When the local source needs amplifier power the MA252 senses this, disconnects the other amplifier and amplifies the local source. The MA252 amplifier is designed to meet the amplifier needs of custom installed systems where high-quality sound is a specific requirement.

Key Features:

Manual and Automatic Power On and Off. The MA252 stereo power amplifier is designed to be turned on when a video signal is detected, music inputs are sensed, a 12-volt trigger is activated or the front panel power switch is pushed on. Power off is automatic in all modes except the front panel power button.

Whole house music override. In homes, yachts, businesses and motor home applications (typically with plasma or large screen TV's) the MA252 features amplifier inputs so that whole house music system can be heard on the local speakers (without the MA252 turned on). When the local source (TV, dish, etc.) needs amp power, the whole house music switches off automatically and the MA252 amplifier plays the local source. Automatic protection circuitry. Each MA252 channel is individually and fully protected against low impedance, overheating, overloading, overvoltage and undervoltage. The protection circuitry automatically restores the amplifier channel as soon as its parameter returns to the safe operating area. Individual input gain adjustment. Each channel features an input gain adjustment pot to adjust each channel for gain and speaker sensitivity variations. The gain adjustments are on the rear of the MA252 so installers normally set the gain.

MA252 specifications

The Knoll Systems MA252 is a versatile and powerful integrated amplifier designed to deliver exceptional audio performance in both residential and commercial settings. Boasting a modern aesthetic, the MA252 combines advanced technologies and high-quality components to provide an immersive listening experience.

One of the standout features of the MA252 is its hybrid design, which incorporates both vacuum tube and solid-state technologies. This combination allows the amplifier to deliver the warm, rich sound characteristic of tube amplifiers while maintaining the precision and reliability of solid-state devices. The vacuum tubes add a unique tonal quality, enhancing midrange frequencies and providing a natural, inviting sound signature.

The MA252 offers a robust output power of 100 watts per channel, ensuring it can drive a variety of speakers with ease. Its high current capabilities enable it to deliver dynamic audio performance, making it suitable for a range of musical genres. Whether listening to delicate vocals or driving bass lines, the MA252 handles every nuance with clarity.

Connectivity options are plentiful, making the MA252 a flexible choice for various audio setups. It features multiple line-level inputs, allowing users to connect a range of sources, including CD players, turntables, and streaming devices. Additionally, the built-in phono stage supports both moving magnet and moving coil cartridges, making it an excellent choice for vinyl enthusiasts.

Another noteworthy technology included in the MA252 is its advanced power supply, which minimizes distortion and enhances overall sound quality. The dual power transformers ensure consistent and stable power delivery, resulting in less noise and improved dynamic range.

The amplifier's elegant design features a brushed aluminum front panel, complemented by a classic meter that provides an analog aesthetic. The intuitive controls make it easy for users to adjust settings and enjoy their music without unnecessary complexity.

In conclusion, the Knoll Systems MA252 stands out as a premium integrated amplifier offering a harmonious blend of vintage warmth and modern functionality. With its hybrid technology, robust output, versatile connectivity, and stylish design, it appeals to audiophiles and casual listeners alike, ensuring an engaging and enjoyable audio experience. Its commitment to high fidelity makes it a worthy consideration for anyone looking to elevate their sound system.