Yamaha MX-1 / MX-2 (1993/1994)

 MX-1 Mx-2 Power Amplifier

Top-ART Ensures Top Quality

Like the preamplifiers the MX-1 and MX-2 benefit from Yamaha's ToP-ART design policy. Every single part was carefully considered during their development, so you can be sure you're purchasing a component with the finest quality throughout. A number of these parts are particulary noteworthy. They use twin massive power transformers and twin heavy-duty extruded aluminum heat sinks. Their block capacitors are extremely large (MX-1 : 36,000 μFx2 and 33,000 μFx2), and all PC board wiring is extra-thick and gold-plated. To support these heavy components and prevent vibration, they have a special ART base inside the chassis. It has a double panel structure, each 1,6 mm thick, and the MX-1 adds extra damping material between the two panels. If these two amps sound weighty, they are; try picking one up. But remember, those heavy parts are where the power comes from.

 Huge Power Output and Low-Impedance Drive Capability

The MX-1 delivers 200 watts per channel of RMS power at 8 ohms, and 250 W at 2 ohms. MX-2 output is 150 W at 8 ohms and 250 W at 2 ohms. Note that both of these amplifiers are rated for continuous output power all the way down to 2 ohms - impossibile for most amplifiers because lower impedances cause much higher amounts of distortion. This means that these amps can be used with low impedance speakers and will function flawlessly even under fluctuating loads caused by variations in the music signal.

Dynamic power levels, or the ability to deliver momentary power levels beyond the RMS power rating, are also exceptionally high. 280/610 W (8/2 ohms) for the MX-1 and 190/400 W (8/2 ohms) for the MX-2. This ability is especially important when playing CDs, which have a very wide dynamic range.

 Hyperbolic Conversion Amplification (HCA)

High performance amplifiers generally use Class A amplification, but the Yamaha-developed HCA circuit goes a step beyond conventional Class A. In a Class A amplifier, when output exceeds a limit determined by the idling current, operation degrades to Class AB, resulting in increased crossover and switching distortion. HCA eliminates this problem by obtaining its output form hyperbolic conversion. So there's less distortion, a wider range of linear operation, and less heat generation.

 Advanced Power Supply (APS)

An amplifer's power supply circuitry is one of the critical determinants of its overall performance. If it does not provide a constant voltage the power transistors will not be able to perform properly. At low power levels, ordinary power supplies are adequate, but at middle and high levels, especially at low impedances, voltage irregularities called ripple are likely to occur. Yamaha's APS circuitry prevents ripple, maintaining  precisely constant voltage at all power levels.

 New Linear Damping Circuit

The damping factor of an ampilfier is its ability to stop the speaker cone from vibrating when it shouldn't, that is when the signal stops. level variations due to high amp impedance tend to reduce the damping factor, and frequency variations cause it to fluctuate. This new circuit cancels the effect of these variations, maintaining an extremely high, stable damping factor (350 at 8 ohms, 20 -20,000 Hz). The result is superior articulation of all sounds and significantly improved frequebcy response.

Other Notable Features

L/R level Controls (on rear panel)

Gold-plated Input Jacks (MX-1 Jack are Solid Brass)

Extra-Large, Anti-Vibration Feet

2-Way Binding Speaker Terminals (Banana Plug Compatible)

 MX-1  Specification

Minimum RMS Output Power per Channel:

200 W (8 Ω) from 20 to 20,000 Hz at no more than 0,008% THD

260 W (4 Ω) from 20 to 20,000 Hz at no more than 0,03% THD

320 W (2 Ω) from 20 to 20,000 Hz at no more than 0,09% THD

Dynamic Power per Channel (by IHF Dynamic headroom Measuring Method):

280 W at 8 ohms

460 W at 6 ohms

630 W at 2 ohms

Dynamic Headroom :

1,46 dB at 8 ohms

2,48 dB at 6 ohms

2,94 dB at 2 ohms

Power Bandwidth (8Ω, 0,03%  THD, half Rated Power):  10 to 60,000 Hz

Damping Factor

(SPA, 8Ω, 20 - 20,000 Hz) : 350

(8Ω, 1 kHz) : 250

Input Sensitivity/Impedance (Main IN):  1,46 V/20 kΩ

Frequency Response (Main In):  20 to 20,000 Hz, ±0,5 dB

Signal-to-Noise Ratio (IHF-A-Network):  125 dB (Main In, Shorted)

Residual Noise (IHF-A-Network):  20 μV

Channel Separation (Vol -30 dB, Main In, Input 5,1 kΩ terminaled)

1 kHz/10 kHz : 80 dB/ 60 dB

Dimensions (W x H x D):  438 x 116 x 486 mm (17-1/4 x 4-9/16 x 19-1/8 inch)

Weight: 24,kg (52 lbs, 14 oz)

MX-2  Specification

Minimum RMS Output Power per Channel:

150 W (8 Ω) from 20 to 20,000 Hz at no more than 0,008% THD

190 W (4 Ω) from 20 to 20,000 Hz at no more than 0,03% THD

230 W (2 Ω) from 20 to 20,000 Hz at no more than 0,09% THD

Dynamic Power per Channel (by IHF Dynamic headroom Measuring Method):

190 W at 8 ohms

310 W at 6 ohms

410 W at 2 ohms

Dynamic Headroom :

1,03 dB at 8 ohms

2,12 dB at 6 ohms

2,51 dB at 2 ohms

Power Bandwidth (8Ω, 0,03%  THD, half Rated Power):  10 to 60,000 Hz

Damping Factor

(SPA, 8Ω, 20 - 20,000 Hz) : 350

(8Ω, 1 kHz) : 250

Input Sensitivity/Impedance (Main IN):  1,26 V/20 kΩ

Frequency Response (Main In):  20 to 20,000 Hz, ±0,5 dB

Signal-to-Noise Ratio (IHF-A-Network):  123 dB (Main In, Shorted)

Residual Noise (IHF-A-Network):  20 μV

Channel Separation (Vol -30 dB, Main In, Input 5,1 kΩ terminaled)

1 kHz/10 kHz : 80 dB/ 60 dB

Dimensions (W x H x D):  438 x 116 x 486 mm (17-1/4 x 4-9/16 x 19-1/8 inch)

Weight: 19,5kg (43 lbs)