Yamaha P-2250 dual-mono power amp

 Yamaha P-series Professional Power Amplifiers P2250

The dual-channel amplifier shall include a rear-panel switch that converts the amplifier to monaural operation, in which case the bridged outputs shall deliver maximum continuous sine wave power output over a 20 Hz to 20 kHz bandwidth of (300 watts, 500 watts) into a minimum 8 ohm load impedance, or (220 watts, 340 watts) into a 16 ohm load with no more than 0,05% thd s/n in bridge mono mode, as established by comparing the maximum output with signal to the minimum output noise with a shorted input, shall be no less than 106 dB measured with a _6 dB/octave low pass filter at 12,47 kHz (equal to a “brick wall” filter at 20 kHz), and no less than 115 dB measured with an IHF “A” weighting network. Channel separation shall be at least 90 db at 1 khz, and shall be at least 70 db at any frequency from 20 Hz to 20 kHz. Slew rate in bridged mono mode shall be at least 90 volts per microsecond, full swing.

Single and Dual –Channel Models in Two Power Ranges

the P1150 is a single channel amplifier rated at 100 watts into 8 ohm or 150 watts into 4 ohm; the dual-channel P2150 delivers the same power output per channel, the P1250 is a single channel  amplifier rated at 170 watts into 8 ohm or 250 watts into 4 ohm, the dual-channel P2250 delivers the same power output per channel.

A rear panel switch on both dual-channel models rewires them internally for use in a bridged , MONO (single-channel) configuration; in this mode the P1250 delivers 200 watts into 16 ohm or 300 watts into 8 ohm, and the P2250 delivers 340 watts into 16 ohm or 500 watts into 4 ohm.

by using both channels of a dual-channel model to drive a single speaker load in the bridged (mono) configuration, it is possible to achieve the wide headroom and dynamic range needed for accurate reproduction of peaks and transient sounds. The P2250 in bridged Mono mode, will deliver 63 volts to the speaker line and therefore may be used to drive a slightly de-rated 70 volt line (for use with a distributed speaker system)

Multiple Protection Techniques Avoid Damaged Speakers

theoretically , a power amplifier is capable of damaging speakers in many ways. The new Yamaha professional amps are designed to eliminate as many potential damage modes as is practical without causing unwanted shut-down or impairment of the sound.

A turn-on transient (a low frequency “thump”) may occur as the power supplies in mixers, console or auxiliary signal processing equipment activate their internal circuits. One does not want these “thumps” to be amplified by the power amp. Or speaker damage might occur. The safest approach here is to disconnect the speakers from the amplifier until all equipment in the sound system has stabilized. That’s why we designed these amplifiers with a relay that disconnects the output until after power has been on a few seconds. This protection is only effective, however, with good operating practice – i.e., if you turn on the amplifier Last – after first turning on the console, electronic crossover, and any signal processing equipment.

If DC were to appear at an amplifier’s output, it would cause speaker voice coils to move to one position and stay there, which can quickly lead to voice coil overheating and premature failure of the speaker. Even relatively low levels of DC can cause this problem, DC can appear at a direct coupled amplifier’s output when the input signal has just a few millivolts of DC offset. That’s the advantage of AC coupled amplifiers such as these. Still, it is conceivable that some DC might appear at the output of an AC-coupled amplifier in the presence of asymmetrical, very low frequency input signals. In any event, high DC levels, as might be caused by a short between the power supply “ralls” and the output , can instantly destroy a speaker or compression driver. To prevent any such catastrophe circuitry in these amplifiers senses the presence of any significant DC component at the output(more than 2 volts), and opens the speaker relay immediately, when this occurs, the front-panel Protection LED turns on. Given that the average 8 ohm speaker has a DC resistance of about 5 ohms, this means that the relay would shut down the output before so much as 1 watt of DC power reached the speaker load.

If a short circuit in the speaker or cable or a very low impedance speaker load overloads the amplifier, current limiting circuitry in the amplifier prevents excessive power from being delivered to the load.

Features

Every effort has been made to provide the features that musicians, soundmen and engineers feel they need in a professional power amplifier. Rather than experiment with exotic designs, we have applied field-proven principles to design amplifiers which are highly stable, and will deliver the kind of reliability enjoyed for over a decade by Yamaha professional and commercial sound products.

Recessed input attenuators with 32 calibrated, detented positions are easily operated. To discourage casual tampering, rubber security covers are included.

Electronically balanced, differential input circuits allow the use of long, shielded 3-wire input cables to reduce susceptibility to hum.

Two methods to connect each input: XLRs combine the advantages of electrostatic and electromagnetic noise rejection, with locking terminals that won’t pull out accidentally should the cable be tugged. Phone jacks provide for fast, compatible connection to equipment that utilizes phone jacks instead of one per channel, we have made it easier to “daisy chain” connect more than one amplifier to a given signal source – on “Y” adapter cable is required.

The output circuitry is fully protected from overloads and short circuits, and the speaker outputs are relay-protected against turn-on transients and DC offset.

five-way binding post output connections provide more secure wiring, better current handling capability, and less tendency to built up contact resistance than typical phone jack outputs. Phone jack outputs are provided for convenience in fast setup situations.

Rated for 4-ohm or higher impedance loads

P2250, in bridged mono mode , can drive 70-volt lins without an output transformer.

Two-stage, temperature-operated cooling fan pulls air through a front panel filter to keep the power transformer and heat sinks cool, further protection afforded by a thermal breaker.

Convenient power cord holders on rear panel enable amp to be set “on end” without damage to connectors; sturdy front panel handles for easy removal from rack and more comfortable carrying.

Well suited to a variety of sound reinforcement, recording and musical instrument applications.

Specifications P2250

Power Output Level (THD =0,05%)

Stereo

20 Hz – 20 kHz :  170 W + 170 W (at 8 Ω ); 250 W + 250 W (at 4 Ω )

1 kHz:  185 W + 185 W (at 8 Ω ); 265 W +265 W (at 4 Ω )

BTL-Mono

20 Hz – 20 kHz :  3400 W (at 16 Ω ); 500 W (at 8 Ω )

1 kHz:  370 W (at 16 Ω ); 530 W (at 8 Ω )

Frequency Response:   10 Hz – 50,000 Hz (8 Ω ) +0 -1 dB

Power Bandwidth (THD =0,1%)

Stereo

10 Hz to 50,000 Hz (85 W) at 8 Ω 

10 Hz to 50,000 Hz (125 W) at 4 Ω 

BTL-Mono

10 Hz to 50,000 Hz (170 W) at 16 Ω 

10 Hz to 50,000 Hz (250 W) at 8 Ω 

Total harmonic Distortion: 

Stereo

Less than 0,007% ( 85 W, 20 Hz – 20 kHz, 8 Ω )

Less than 0,003% ( 85 W, 1 kHz, 8 Ω )

Less than 0,005% ( 75 W, 1 kHz, 4 Ω )

Less than 0,01% ( 125 W, 20 Hz – 20 kHz, 4 Ω )

BTL-Mono

Less than 0,007% ( 85 W, 20 Hz – 20 kHz, 16 Ω )

Less than 0,003% ( 85 W, 1 kHz, 16 Ω )

Less than 0,005% ( 125 W, 1 kHz, 8 Ω )

Less than 0,01% ( 125 W, 20 Hz – 20 kHz, 8 Ω )

Intermodulation  Distortion (60 Hz : 7 kHz = 4:1)

Stereo

less than 0,005% (85 W, 8 Ω )

less than 0,01% (12 W, 4 Ω )

BTL-Mono

less than 0,01% (250 W, 8 Ω )

less than 0,01% (170 W, 16 Ω )

Damping Factor

Better than 110 (1 kHz , 8 Ω); better than 55 (1 kHz  , 4 Ω )

Signal-to-Noise-Ratio: 

Stereo

Better than 110 dB (Input Short; at 12,47 kHz, -6 dB/octave LPF)

Better than 115 dB (Input Short, IHF A Network)

BTL-Mono

Better than 106 dB (Input Short; at 12,47 kHz, -6 dB/octave LPF)

Better than 110 dB (Input Short, IHF A Network)

Slew Rate

Stereo :  ±50 V/µsec (8 ohm, Full Swing)

BTL-Mono :  ±90 V/µsec (16 ohm, Full Swing)

Sensitivity :  +4 dB (1,23 V rms) for nominal output (4 Ω load)

Voltage Gain:  28,3 dB

Input Impedance:  better than 15 k Ω, Balanced or Unbalanced (Att. Max)

Residual Noise (Input Att. Minimum)

Less than -80 dBm, -6 dB/oct. LPF at 12,47 kHz 

Less than -90 dBm, IHF A network

Indicators

Signal:  Green LED (-20 Hz to 20 kHz, Vo better than 2 V

Clipping:  Red LED Total harmonic Distortion: better than 1%

Protection: Red LED (during the protection or muting is on)

Pilot:  Red LED Power ON

Protection Circuits

Muting:  6 ±2sec After Power ON

DC Sense:  DC ±2  sec. Ouptut Voltage

Thermal:  better than 85°C Heat sink temperature

PC Limiter:  ON RL less than 2 Ω 

FAN Circuit

Better than 60°C High speed run, Heat sink temperature

Less than 45°C Restoration of a low speed run, Heat sink temperature

Front Controls:  2 x 32 step Input Attenuator (0 to -20 dB in 1 dB steps, -20 to -30 dB in 2 dB steps, then -33, -37, -42, -50, -60 dB, and infinite attenuation

Push ON/Push Off Power Switch

Rear Control:  Mono/Stereo Mode Switch

Power Requirements

220/240 V AC 50/60 Hz (General model) 120 V AC, 60 Hz (US and Canada models)

Power Consumption

1300 W (General mode); 850 W, 950 VA (US and Canada model)

dimensions (W x H x D):  480 x 132 x 423 MM (18-7/8” x 5-1/4” x 16-5/8”)

Weight:  19 kg (41,8 lbs)

Yamaha P-2150 dual-mono power amp

Yamaha P-series Professional Power Amplifiers P2150

The dual-channel amplifier shall include a rear-panel switch that converts the amplifier to monaural operation, in which case the bridged outputs shall deliver maximum continuous sine wave power output over a 20 Hz to 20 kHz bandwidth of (300 watts, 500 watts) into a minimum 8 ohm load impedance, or (220 watts, 340 watts) into a 16 ohm load with no more than 0,05% thd s/n in bridge mono mode, as established by comparing the maximum output with signal to the minimum output noise with a shorted input, shall be no less than 106 dB measured with a _6 dB/octave low pass filter at 12,47 kHz (equal to a “brick wall” filter at 20 kHz), and no less than 115 dB measured with an IHF “A” weighting network. Channel separation shall be at least 90 db at 1 khz, and shall be at least 70 db at any frequency from 20 Hz to 20 kHz. Slew rate in bridged mono mode shall be at least 90 volts per microsecond, full swing.

Single and Dual –Channel Models in Two Power Ranges

the P1150 is a single channel amplifier rated at 100 watts into 8 ohm or 150 watts into 4 ohm; the dual-channel P2150 delivers the same power output per channel, the P1250 is a single channel  amplifier rated at 170 watts into 8 ohm or 250 watts into 4 ohm, the dual-channel P2250 delivers the same power output per channel.

A rear panel switch on both dual-channel models rewires them internally for use in a bridged , MONO (single-channel) configuration; in this mode the P1250 delivers 200 watts into 16 ohm or 300 watts into 8 ohm, and the P2250 delivers 340 watts into 16 ohm or 500 watts into 4 ohm.

by using both channels of a dual-channel model to drive a single speaker load in the bridged (mono) configuration, it is possible to achieve the wide headroom and dynamic range needed for accurate reproduction of peaks and transient sounds. The P2250 in bridged Mono mode, will deliver 63 volts to the speaker line and therefore may be used to drive a slightly de-rated 70 volt line (for use with a distributed speaker system)

Multiple Protection Techniques Avoid Damaged Speakers

theoretically , a power amplifier is capable of damaging speakers in many ways. The new Yamaha professional amps are designed to eliminate as many potential damage modes as is practical without causing unwanted shut-down or impairment of the sound.

A turn-on transient (a low frequency “thump”) may occur as the power supplies in mixers, console or auxiliary signal processing equipment activate their internal circuits. One does not want these “thumps” to be amplified by the power amp. Or speaker damage might occur. The safest approach here is to disconnect the speakers from the amplifier until all equipment in the sound system has stabilized. That’s why we designed these amplifiers with a relay that disconnects the output until after power has been on a few seconds. This protection is only effective, however, with good operating practice – i.e., if you turn on the amplifier Last – after first turning on the console, electronic crossover, and any signal processing equipment.

If DC were to appear at an amplifier’s output, it would cause speaker voice coils to move to one position and stay there, which can quickly lead to voice coil overheating and premature failure of the speaker. Even relatively low levels of DC can cause this problem, DC can appear at a direct coupled amplifier’s output when the input signal has just a few millivolts of DC offset. That’s the advantage of AC coupled amplifiers such as these. Still, it is conceivable that some DC might appear at the output of an AC-coupled amplifier in the presence of asymmetrical, very low frequency input signals. In any event, high DC levels, as might be caused by a short between the power supply “ralls” and the output , can instantly destroy a speaker or compression driver. To prevent any such catastrophe circuitry in these amplifiers senses the presence of any significant DC component at the output(more than 2 volts), and opens the speaker relay immediately, when this occurs, the front-panel Protection LED turns on. Given that the average 8 ohm speaker has a DC resistance of about 5 ohms, this means that the relay would shut down the output before so much as 1 watt of DC power reached the speaker load.

If a short circuit in the speaker or cable or a very low impedance speaker load overloads the amplifier, current limiting circuitry in the amplifier prevents excessive power from being delivered to the load.

Features

Every effort has been made to provide the features that musicians, soundmen and engineers feel they need in a professional power amplifier. Rather than experiment with exotic designs, we have applied field-proven principles to design amplifiers which are highly stable, and will deliver the kind of reliability enjoyed for over a decade by Yamaha professional and commercial sound products.

Recessed input attenuators with 32 calibrated, detented positions are easily operated. To discourage casual tampering, rubber security covers are included.

Electronically balanced, differential input circuits allow the use of long, shielded 3-wire input cables to reduce susceptibility to hum.

Two methods to connect each input: XLRs combine the advantages of electrostatic and electromagnetic noise rejection, with locking terminals that won’t pull out accidentally should the cable be tugged. Phone jacks provide for fast, compatible connection to equipment that utilizes phone jacks instead of one per channel, we have made it easier to “daisy chain” connect more than one amplifier to a given signal source – on “Y” adapter cable is required.

The output circuitry is fully protected from overloads and short circuits, and the speaker outputs are relay-protected against turn-on transients and DC offset.

five-way binding post output connections provide more secure wiring, better current handling capability, and less tendency to built up contact resistance than typical phone jack outputs. Phone jack outputs are provided for convenience in fast setup situations.

Rated for 4-ohm or higher impedance loads

P2250, in bridged mono mode , can drive 70-volt lins without an output transformer.

Two-stage, temperature-operated cooling fan pulls air through a front panel filter to keep the power transformer and heat sinks cool, further protection afforded by a thermal breaker.

Convenient power cord holders on rear panel enable amp to be set “on end” without damage to connectors; sturdy front panel handles for easy removal from rack and more comfortable carrying.

Well suited to a variety of sound reinforcement, recording and musical instrument applications.

Specifications P2150

Power Output Level (THD =0,05%)

Stereo

20 Hz – 20 kHz :  100 W + 100 W (at 8 Ω ); 150 W + 150 W (at 4 Ω )

1 kHz:  105 W + 105 W (at 8 Ω ); 165 W +165 W (at 4 Ω )

BTL-Mono

20 Hz – 20 kHz :  220 W (at 16 Ω ); 300 W (at 8 Ω )

1 kHz:  250 W (at 16 ohm); 330 W (at 8 ohm

Frequency Response:   10 Hz – 50,000 Hz (8 Ω ) +0 -1 dB

Power Bandwidth (THD =0,1%)

Stereo

10 Hz to 50,000 Hz (55 W) at 8 Ω 

10 Hz to 50,000 Hz (75 W) at 4 Ω 

BTL-Mono

10 Hz to 50,000 Hz (110 W) at 16 Ω 

10 Hz to 50,000 Hz (150 W) at 8 Ω 

Total harmonic Distortion: 

Stereo

Less than 0,007% ( 55 W, 20 Hz – 20 kHz, 8 Ω )

Less than 0,003% ( 55 W, 1 kHz, 8 Ω )

Less than 0,005% ( 75 W, 1 kHz, 4 Ω )

Less than 0,01% ( 75 W, 20 Hz – 20 kHz, 4 Ω )

BTL-Mono

Less than 0,007% ( 110 W, 20 Hz – 20 kHz, 16 Ω )

Less than 0,003% ( 110 W, 1 kHz, 16 Ω )

Less than 0,005% ( 150 W, 1 kHz, 8 Ω )

Less than 0,01% ( 150 W, 20 Hz – 20 kHz, 8 Ω )

Intermodulation  Distortion (60 Hz : 7 kHz = 4:1)

Stereo

less than 0,005% (55 W, 8 Ω )

less than 0,01% (75 W, 4 Ω )

BTL-Mono

less than 0,01% (150 W, 8 Ω )

less than 0,01% (110 W, 16 Ω )

Damping Factor

Better than 110 (1 kHz , 8 Ω ); >55 (1 kHz , 4 Ω )

Signal-to-Noise-Ratio: 

Stereo

Better than 110 dB (Input Short; at 12,47 kHz, -6 dB/octave LPF)

Better than 115 dB (Input Short, IHF A Network)

BTL-Mono

Better than 106 dB (Input Short; at 12,47 kHz, -6 dB/octave LPF)

Better than 110 dB (Input Short, IHF A Network)

Slew Rate

Stereo :  ± 50 V/µsec (8 ohm, Full Swing)

BTL-Mono :  ±90 V/µsec (16 Ω , Full Swing)

Sensitivity :  +4 dB (1,23 V rms) for nominal output (4 Ω  load)

Voltage Gain:  26,0 dB

Input Impedance:  better than  15 k Ω , Balanced or Unbalanced (Att. Max)

Residual Noise (Input Att. Minimum)

Less than -80 dBm, -6 dB/oct. LPF at 12,47 kHz 

Less than -90 dBm, IHF A network

Indicators

Signal:  Green LED(-20 Hz to 20 kHz, Vo better than  2 V

Clipping:  Red LED Total harmonic Distortion: better than 1%

Protection: Red LED (during the protection or muting is on)

Pilot:  Red LED Power ON

Protection Circuits

Muting:  6 ± 2sec After Power ON

DC Sense:  DC ±2 sec. Ouptut Voltage

Thermal:  better than 85°C Heat sink temperature

PC Limiter:  ON RL less than 2 Ω 

FAN Circuit

Better than 60°C High speed run, Heat sink temperature

Less than 45°C Restoration of a low speed run, Heat sink temperature

Front Controls:  2 x 32 step Input Attenuator (0 to -20 dB in 1 dB steps, -20 to -30 dB in 2 dB steps, then -33, -37, -42, -50, -60 dB, and infinite attenuation

Push ON/Push Off Power Switch

Rear Control:  Mono/Stereo Mode Switch

Power Requirements

220/240 V AC 50/60 Hz (General model) 120 V AC, 60 Hz (US and Canada models)

Power Consumption

800 W (General mode); 500 W, 600 VA (US and Canada model)

dimensions (W x H x D):  480 x 132 x 423 MM (18-7/8” x 5-1/4” x 16-5/8”)

Weight:  17 kg (37,4 lbs)

 

Yamaha P-1250 monaural power amp

Yamaha P-series Professional Power Amplifiers P1250 

The power amplifier shall have an input sensitivity of +4 dBn, requiring no more than 1,23 volts RMS to be driven to rated output into a 4 ohm load. The maximum continuous average sine wave power output over a 20 Hz to 20 kHz bandwidth for a single channel shall be (150 watts, 250 watts) onto a minimum 4 ohm load impedance, or (100 watts, 170 watts) into an 8 ohm load with no more than 0,05% thd.

Total harmonic Distortion measured at half rated power, from 20 Hz to 20 kHz, shall be no more than 0,01% . maximum intermodulation distortion, measured using the SMPTE method of 60 Hz and 7 kHz tones mixed in a 4:1 ratio, shall be no more than 0,01% measured at rated power output. Power bandwidth shall be no less than 10 Hz to 50 kHz at half rated power output, and frequency response shall be +0 dB, -1 dB from 10 Hz to 50 kHz. s/n as established by comparing the maximum output with signal to the minimum output noise with a shorted input, shall be no less than 110 dB measured with a -6 dB/octave low pass filter at 12,47 kHz (equal to a “brick wall” filter at 20 kHz), and no less than 115 dB measured with an IHF “A” weighting network. Residual output noise, measured with the input attenuator set at infinite attenuation, shall be no more than _80 dBm with a -6 dB/octave low pass filter at 12,47 kHz, or no more than -90 dBm with an IHF “A” weighting network. Slew rate shall be at least 50 volts per microsecond, full swing.

The amplifier input(s) shall be equipped with both an XLR-3 type connector and a pair of Tip/Ring/Sleeve ¼-inch phone jacks, wired in parallel. The input shall be of the electronically balanced, differential type, with an input impedance of no less than 15 k ohm presented to either balanced or unbalanced sources. The amplifier output(s) shall be equipped with a set of 5-way binding posts for positive, high-current connections, and with parallel-wired Tip/Sleeve 1-4-inch phone jacks for wiring convenience.

Input level shall be adjustable by means of (one or two) detented input attenuator(s) calibrated in 32 steps of from zero to infinite attenuation. The attenuator(s) shall be recessed, and shall be designed so as to be easily adjustable by hand, without any tools. To avoid casual or accidental setting changes, a security cover for the attenuator(s) shall also be provided.

Protection for the speaker load shall be established by means of an output-disconnect relay that is timed out when power is first applied to avoid transients from reaching the load, and that immediately disconnects the load and turns on a front-panel protection indicator in the event that more than 2 volts DC appears across the output. Further protection for the amplifier and load shall be provided by VI limiting circuitry which automatically reduces the power output in the event the load impedance is below 2 ohm for a single channel, (4 ohm for a dual-channel model in bridged mono configuration). The amplifier shall also include a full-time 2-speed fan which operates at high speed under severe thermal stress, and automatically resets to a lower speed as appropriate. Cooling air shall be drawn through a removable cleanable front-panel filter, and exhausted via ports in the tip and side panels of the amplifier.

Signal level indication (per each channel on dual-channel models) shall be provided by two LEDs, one of which turns on when the output THD is equal to or above 1%, which would indicate the onset of clipping, and one which turns on when the output level is equal to or greater than 2 volts RMS, which would indicate the presence of program signal.

Specifications P1250

Power Output Level (THD =0,05%)

20 Hz – 20 kHz :  170 W (at 8 Ω ); 250 W (at 4 Ω )

1 kHz:  185 W (at 8 Ω ); 265 W (at 4 Ω )

Frequency Response:   10 Hz – 50,000 Hz (8 Ω ) +0 -1 dB

Power Bandwidth (THD = 0,1%)

10 Hz to 100,000 Hz (85 W) at 8 ohm

10 Hz to 100,000 Hz (125 W) at 4 ohm

Total harmonic Distortion: 

Less than 0,007% ( 85 W, 20 Hz – 20 kHz, 8 Ω )

Less than 0,003% ( 85 W, 1 kHz, 8 Ω )

Less than 0,005% ( 125 W, 1 kHz, 4 Ω )

Less than 0,01% ( 1255 W, 20 Hz – 20 kHz, 4 Ω )

Intermodulation  Distortion (60 Hz : 7 kHz = 4:1)

less than 0,005% (85 W, 8 Ω )

less than 0,01% (125 W, 4 Ω )

Damping Factor

Better than 110 (1 kHz , 8 Ω ); >55 (1 kHz  , 4 Ω  )

Signal-to-Noise-Ratio: 

Better than 110 dB (Input Short; 12,47 kHz , -6 dB/octave LPF)

Better than 115 dB (Input Short, IHF A Network)

Slew Rate

± 50 V/µsec (8 Ω , Full Swing)

Sensitivity :  +4 dB (1,23 V rms) for nominal output (4 Ω  load)

Voltage Gain:  28,3 dB

Input Impedance:  better than  15 k Ω , Balanced or Unbalanced (Att. Max)

Residual Noise (Input Att. Minimum)

Less than -80 dBm, -6 dB/oct. LPF at 12,47 kHz 

Less than -90 dBm, IHF A network

Indicators

Signal:  Green LED(-20 Hz to 20 kHz, Vo> 2 V

Clipping:  Red LED Total harmonic Distortion: better than 1%

Protection: Red LED (during the protection or muting is on)

Pilot:  Red LED Power ON

Protection Circuits

Muting:  6 ± 2sec After Power ON

DC Sense:  DC ± 2 V Ouptut Voltage

Thermal:  better than 85°C Heat sink temperature

PC Limiter:  ON RL less than 2 Ω 

FAN Circuit

Better than 60°C High speed run, Heat sink temperature

Less than 45°C Restoration of a low speed run, Heat sink temperature

Front Controls:  32 step Input Attenuator (0 to -20 dB in 1 dB steps, -20 to -30 dB in 2 dB steps, then -33, -37, -42, -50, -60 dB, and infinite attenuation

Push ON/Push Off Power Switch

Power Requirements

220/240 V AC 50/60 Hz (General model) 120 V AC, 60 Hz (US and Canada models)

Power Consumption

600 W (General mode); 400 W, 450 VA (US and Canada model)

Dimensions (W x H x D):  480 x 132 x 423 MM (18-7/8” x 5-1/4” x 16-5/8”)

Weight:  15 kg (33 lbs)

 

Yamaha P-1150 monaural power amp

Yamaha P-series Professional Power Amplifiers P1150 

The power amplifier shall have an input sensitivity of +4 dBn, requiring no more than 1,23 volts RMS to be driven to rated output into a 4 ohm load. The maximum continuous average sine wave power output over a 20 Hz to 20 kHz bandwidth for a single channel shall be (150 watts, 250 watts) onto a minimum 4 ohm load impedance, or (100 watts, 170 watts) into an 8 ohm load with no more than 0,05% thd.

Total harmonic Distortion measured at half rated power, from 20 Hz to 20 kHz, shall be no more than 0,01% . maximum intermodulation distortion, measured using the SMPTE method of 60 Hz and 7 kHz tones mixed in a 4:1 ratio, shall be no more than 0,01% measured at rated power output. Power bandwidth shall be no less than 10 Hz to 50 kHz at half rated power output, and frequency response shall be +0 dB, -1 dB from 10 Hz to 50 kHz. s/n as established by comparing the maximum output with signal to the minimum output noise with a shorted input, shall be no less than 110 dB measured with a -6 dB/octave low pass filter at 12,47 kHz (equal to a “brick wall” filter at 20 kHz), and no less than 115 dB measured with an IHF “A” weighting network. Residual output noise, measured with the input attenuator set at infinite attenuation, shall be no more than _80 dBm with a -6 dB/octave low pass filter at 12,47 kHz, or no more than -90 dBm with an IHF “A” weighting network. Slew rate shall be at least 50 volts per microsecond, full swing.

The amplifier input(s) shall be equipped with both an XLR-3 type connector and a pair of Tip/Ring/Sleeve ¼-inch phone jacks, wired in parallel. The input shall be of the electronically balanced, differential type, with an input impedance of no less than 15 k ohm presented to either balanced or unbalanced sources. The amplifier output(s) shall be equipped with a set of 5-way binding posts for positive, high-current connections, and with parallel-wired Tip/Sleeve 1-4-inch phone jacks for wiring convenience.

Input level shall be adjustable by means of (one or two) detented input attenuator(s) calibrated in 32 steps of from zero to infinite attenuation. The attenuator(s) shall be recessed, and shall be designed so as to be easily adjustable by hand, without any tools. To avoid casual or accidental setting changes, a security cover for the attenuator(s) shall also be provided.

Protection for the speaker load shall be established by means of an output-disconnect relay that is timed out when power is first applied to avoid transients from reaching the load, and that immediately disconnects the load and turns on a front-panel protection indicator in the event that more than 2 volts DC appears across the output. Further protection for the amplifier and load shall be provided by VI limiting circuitry which automatically reduces the power output in the event the load impedance is below 2 ohm for a single channel, (4 ohm for a dual-channel model in bridged mono configuration). The amplifier shall also include a full-time 2-speed fan which operates at high speed under severe thermal stress, and automatically resets to a lower speed as appropriate. Cooling air shall be drawn through a removable cleanable front-panel filter, and exhausted via ports in the tip and side panels of the amplifier.

Signal level indication (per each channel on dual-channel models) shall be provided by two LEDs, one of which turns on when the output THD is equal to or above 1%, which would indicate the onset of clipping, and one which turns on when the output level is equal to or greater than 2 volts RMS, which would indicate the presence of program signal.

Specifications P1150

Power Output Level (THD =0,05%)

20 Hz – 20 kHz :  100 W (at 8 ohm); 150 W (at 4 Ω )

1 kHz:  105 W (at 8 Ω ); 165 W (at 4 Ω )

fr:  10 Hz – 50,000 Hz (8 Ω ) +0 -1 dB

Power Bandwidth (THD <=0,1%)

10 Hz to 100,000 Hz (55 W) at 8 Ω 

10 Hz to 100,000 Hz (75 W) at 4 Ω 

Total harmonic Distortion: 

Less than 0,007% ( 55 W, 20 Hz – 20 kHz, 8 Ω )

Less than 0,003% ( 55 W, 1 kHz, 8 Ω )

Less than 0,005% ( 75 W, 1 kHz, 4 Ω )

Less than 0,01% ( 75 W, 20 Hz – 20 kHz, 4 Ω )

Intermodulation  Distortion (60 Hz : 7 kHz = 4:1)

less than 0,005% (55 W, 8 Ω )

less than 0,01% (75 W, 4 Ω )

Damping Factor

Better than 110 (1 kHz , 8 Ω ); better than 55 (1 kHz  , 4 Ω )

Signal-to-Noise-Ratio: 

Better than 110 dB (Input Short; 12,47 kh z, -6 dB/octave LPF)

Better than 115 dB (Input Short, IHF A Network)

Slew Rate

± 50 V/µsec  (8 Ω , Full Swing)

Sensitivity :  +4 dB (1,23 V rms) for nominal output (4 Ω  load)

Voltage Gain:  26,0 dB

Input Impedance:  better than  15 k Ω , Balanced or Unbalanced (Att. Max)

Residual Noise (Input Att. Minimum)

Less than -80 dBm, -6 dB/oct. LPF at 12,47 kHz

Less than -90 dBm, IHF A network

Indicators

Signal:  Green LED(-20 Hz to 20 kHz, Vo better than  2 V

Clipping:  Red LED Total harmonic Distortion: better than 1%

Protection: Red LED (during the protection or muting is on)

Pilot:  Red LED Power ON

Protection Circuits

Muting:  6 ± 2sec After Power ON

DC Sense:  DC ± 2 V Ouptut Voltage

Thermal:  better than 85°C Heat sink temperature

PC Limiter:  ON RL less than 2 Ω 

FAN Circuit

Better than 60°C High speed run, Heat sink temperature

Less than 45°C Restoration of a low speed run, Heat sink temperature

Front Controls:  32 step Input Attenuator (0 to -20 dB in 1 dB steps, -20 to -30 dB in 2 dB steps, then -33, -37, -42, -50, -60 dB, and infinite attenuation

Push ON/Push Off Power Switch

Power Requirements

220/240 V AC 50/60 Hz (General model) 120 V AC, 60 Hz (US and Canada models)

Power Consumption

400 W (General mode); 250 W, 300 VA (US and Canada model)

dimensions (W x H x D):  480 x 132 x 423 MM (18-7/8” x 5-1/4” x 16-5/8”)

Weight:  13 kg (28,6 lbs)

 

Adcom GFA-545 power amp

Adcom GFA-545 represents the most advanced thinking in audio amplifier design. At 100 watts per channel, the GFA-545 offers an exceptional value; superior performance at a reasonable price.

Some of the outstanding features of this amplifier are:

100 watts per channel, 20 Hz - 20 kHz, into an 8 Ω  load with both channels driven with less than 0,09% Total Harmonic Distortion.

The ability to drive low impedance loads

Large Heat sinks to dissipate heat from the power transistors

External and internal fuses which are designed to protect your loudspeakers from possible damage and also to protect the amp itself under all but the severest abuse of operating conditions.

A thermal cutoff is also employed to protect the amplifier under high temperature conditions.

Instantaneous Distortion Alert which indicates when distortion products are above the 1% level.

 

The instantaneous Distortion Alert is a unique distortion detection circuit which reads all forms of distortion - T.H.D., Intermodulation DIstortion, Slew Induced, and DC-offset, peak LEDs, one per channel, will glow when distortion is above 1% regardless of the load impedance or reactance in use, the LEDs may occasionally flicker under high volume listening. It they glow brightly or are on most of the time that you are listening, you are overdriving your equipment and should turn down your volume control.

 

The GFA-545 is a truly significant contribution to the advancement of sound technology. To ensure that the quality of construction is on par with the quality of the sonics, (a much neglected area in many other amplifiers) the GFA-535 has been carefully developed with computer controlled metal fabrication techniques that maintain 0,005 of an inch tolerances throughout. Full electrical inspection of each and every circuit board, sub-assembly , as well as the finished amplifier, provide a mechanically and sonically superior product for your enjoyment.

 

Specifications

Continuous Power Output (both channels, 20 Hz - 20 kHz, less than 0,09% T.H.D.):

100 watts/channel at 8 Ω

150 watts/channel at 4 Ω

Signal-to-Noise Ratio (A-weighted, Full output):  better than 106 dB

Input Impedance:  22 k Ω

Input Sensitivity

For rated Output :  1,3 Volt

For 1 watt :  130 mV

Damping Factor (20 Hz - 20 kHz):  better than 130

Dynamic Headroom (at 4 Ω ):  2,6 dB

Available Voltage:  120 V at 60 Hz, 220 V at 50 Hz

Dimensions (W x H x D):  432 x 140 x 318 mm (17" x 5-1/2" x 12-1/2")

Shipping Weight:  12,2 kg (27 lbs)

 

Adcom GFA-535 power amp

Adcom GFA-535 represents the most advanced thinking in audio amplifier design. At 60 watts per channel, the GFA-535 offers an exceptional value; superior performance at a reasonable price.

Some of the outstanding features of this amplifier are:

60 watts per channel, 20 Hz - 20 kHz, into an 8 Ω  load with both channels driven with less than 0,09% Total Harmonic Distortion.

The ability to drive low impedance loads

Output for 2 pairs of speakers

Two additional AC outlets for a CD Player, Tuner, or other audio components up to 100 watts maximum

Instantaneous Distortion Alert which indicates when distortion products are above the 1% level.

The instantaneous Distortion Alert is a unique distortion detection circuit which reads all forms of distortion - T.H.D., Intermodulation DIstortion, Slew Induced, and DC-offset, peak LEDs, one per channel, will glow when distortion is above 1% regardless of the load impedance or reactance in use, the LEDs may occasionally flicker under high volume listening. It they glow brightly or are on most of the time that you are listening, you are overdriving your equipment and should turn down your volume control.

The GFA-535 is a truly significant contribution to the advancement of sound technology. To ensure that the quality of construction is on par with the quality of the sonics, (a much neglected area in many other amplifiers) the GFA-535 has been carefully developed with computer controlled metal fabrication techniques that maintain 0,005 of an inch tolerances throughout. Full electrical inspection of each and every circuit board, sub-assembly , as well as the finished amplifier, provide a mechanically and sonically superior product for your enjoyment. At the time of its design, no other product on the market which offered the design and construction quality of the GFA-535 at anything close to its selling price.

 

Specifications

Continuous Power Output (both channels, 20 Hz - 20 kHz, less than 0,09% T.H.D.):

60 watts/channel at 8 Ω

100 watts/channel at 4 Ω

Signal-to-Noise Ratio (A-weighted, Full output):  better than 106 dB

Input Impedance:  22 k Ω

Input Sensitivity

For rated Output :  1,0 Volt

For 1 watt :  130 mV

Damping Factor (20 Hz - 20 kHz):  better than 130

Dynamic Headroom (at 4 Ω ):  3 dB

Available Voltage:  120 V at 60 Hz, 220 V at 50 Hz

Dimensions (W x H x D):  432 x 83 x 318 mm (17" x 3-1/4" x 12-1/2")

Shipping Weight:  10 kg (22 lbs)

 

Onkyo Icon Series M-80 power amplifier

Icon Series M-80 Power Amplifier

 

Refined Style You Can Feel

Just as your favorite music resonates on an emotional level, premium design is felt instinctively. Intuitively. The Onkyo Icon Series is meticulously designed for simplicity and balance, blending an elegant form factor with classic hi-fi details. Carefully selected materials and tactile buttons and knobs elevate the user experience to something greater than the sum of its parts.

 

Superior Sound Starts with Onkyo

Sophisticated circuitry, elevated design choices, and next-generation tech are weaved into every millimeter of Onkyo’s new Icon Series. Our dedicated engineers believe everyone deserves an exceptional listening experience with all the nuance, detail, and emotion that the artists or players intended. The content played through any of our Icon Series products isn’t just heard – it’s felt.

 

Powering The Music That Moves You

The M-80 uses a three-stage Inverted Darlington Amplifier. The three-stage Inverted Darlington Amplifier has a very low output impedance and drives speakers powerfully with a large current. Also, by keeping NFB (Negative Feedback) low, it is not affected by noise from the speaker. It offers a powerful yet highly resolving and informative sound. The M-80’s output stage transistors are in parallel configuration, which provides excellent instantaneous current supply capability, further enhancing the rise of sound and the sense of power. The driver stage of the M-80 amplifier uses DIDRC (Dynamic Intermodulation Distortion Reduction Circuitry). Reducing beats generated signals(noise) in the ultra-high frequency band by DIDRC’s high slew rate designand helps produce the natural sound of an analog record.

 

Cutting Edge Compomentry for Captivating Playback
The M-80 housing consists of two aluminum side panels and a steel top panel. The three-piece construction of the housings increases rigidity and improves seismic resistance. Various vibrations are suppressed and sound quality is improved.

 

Create Your Perfect System

The M-80 has an output power of 130w(FTC, 8Ω, 20Hz - 20kHz, THD 1%, 2ch driven) / 200w(4Ω, 1kHz, THD 0.7%, 2ch driven) which allows it to powerfully drive large speakers and bring you dynamic acoustic information. For example, Klipsch Forte speakers paired with the P-80 and M-80 would maximize the dynamic and extended sound of the Forte.

 

From Onkyo Academy: The Benefits Of A Power Amplifier

A power amplifier receives the signal from your pre-amp and literally powers it into your speakers. Think of your pre-amp as a brain, and your power amplifier as the muscle. Separating your amplifiers into pre- and power gives you ultimate flexibility in audio playback. Since they are not affected by each other’s circuits, they can provide high-resolution sound quality through even cleaner signal transmission. Audiophiles are well-known to prefer specific power amps and the way they impact sound quality and coloration. The M-80 is a power amplifier that reproduces the full range of artists or players’ intentions in their music and drives you into a world of emotion.

 

Specifications

Output Power:

130 W (FTC 8 Ω, 20 Hz - 20 kHz, THD 1%, 2-ch driven)

200 W (4 Ω, 1 kHz, THD 0.7%, 2-ch driven)

Amplifier Channel:  2 Ch

Amplifier Type:  Class AB

Frequency Response:  5 Hz ~ 100 kHz (+1/-3 dB)

Speaker Impedance:  4 - 16 Ω

Analog Audio Input
RCA (Unbalanced) x 1pair

XLR (Balanced) x 1pair

12 V TRIGER Input (1/8” (3.5 mm) Jack)

Power Consumption: 445 W, 51 W (idle), Less than 0.3 W (Standby)

Dimensions (W X H X D):  435 x 135 x 345 mm (17.1” x 5.3” x 13.6”)

Weight:  13.5 kg

Finish:  Black or silver

 

Kyocera B-901 power amp

 

MOS FET Power Amplifier

Incorporating Direct Coupled Triple Push-Pull MOS FET Power Output

 

Features

Powe Switch

Protection Indicator

Peak Indicator

Input Jack

Input sensitivity switch

Power Indicator

Speaker terminals

 AC outlet

 

Specifications

Power Amplifier

Power Output

130 W + 130 W at 8 Ω , 20 Hz - 20 kHz

180 W + 180 W at 4 Ω , 20 Hz - 20 kHz

Total Harmonic Distortion

0,01% at 8 Ω , 20 Hz - 20 kHz

0,02% at 4 Ω , 20 Hz - 20 kHz

Frequency Response

20 Hz - 20,000 Hz +0 -0,2 dB

5 Hz - 100,000 Hz +0 -1,0 dB

Signal-to-Noise Ratio:  -120 dB

Hum and Noise:  0,2 mV

Damping Factor (8 Ω , 50 Hz):  80

Input Sensitivity/Impedance"  1,5 V; 3,0 V /30 k Ω

Power Supply:  AC 120 V, 60 Hz

Power Consumption:  500 W

Dimensions (W x H x D):  18-7/16" x 7-3/16" x 15-11/16"

Weight:  48,4 lbs

 

Quad 405-2 power amplifier

More than 60,000 Quad 405 current dumping amplifiers are in use around the world providing the "closest approach to the original sound" in the homes of serious music listeners, in recording and broadcasting studios and for sound reinforcement where quality is of prime importance.

The Quad 405-2 exploits improvements in component technology to provide more VA into a wider variety of loads than the original Quad 405 without compromising performance and reliability.

The Quad 405-2 will produce perceptibly higher sound pressure levels from the majority of loudspeakers than the original Quad 405, which will be of significant benefit with the increased dynamic range of modern programme sources.

The 405-2 uses "current dumping", a Quad invention based on feedforward error correction which eliminates many of the problems traditionally associated with transistor amplifiers.

"feedforward error correction" was first proposed by Harold Black in 1928, in which a derived error signal is added to the output signal of an amplifier in exactly the right amount to cancel the distortion produced by the amplifier. While it is relatively easy to add error current to signal current without interaction, as in Black's invention, it is very much more difficult to do so in voltage terms. Loudspeakers require a stiff source and so "feedforward" has found no successful application in audio amplifiers.

What Quad has done - not quite as easy as it sounds - is to produce a current controlled amplifier, apply a special type of feedforward current error correction and then apply overall voltage feedback to convert the whole to a voltage amplifier. There is in effect, both a low powered very high quality amplifier and a high powered heavy duty amplifier, the current dumpers. The low power amplifier controls the loudspeakers at all times, calling upon the high power section to provide most of the muscle. The small amplifier which carries the error signal is so arranged that provided the large power transistors get within the target area of the required output current, it will fill in the remainder accurately and completely.

The quality is solely dependent upon the performance of the low powered high quality amplifier together with four passive components. When correctly designed, all distortion in the output stage is reduced to zero.

With this technique it is possible to produce an amplifier of very high performance without using carefully matched relatively fragile output devices. There are no crossover biasing problems, no alignment or adjustment is required to obtain optimum performance and nothing can go out of alignment during life. In the event of component failure, replacement can be effected and performance restored without realignment.

 

Specifications

Power Output:  the amplifier is intended for use with loudspeakers of 4 - 16 Ω  nominal impedance.

Power and distortion for various frequencies

Continuous sine wave into 8 Ω , resistive load

100 Hz any level up to 100 watts : less than0,01% Dtot

1,100 Hz any level up to 100 watts : less than0,01% Dtot

10,100 Hz any level up to 100 watts : less than0,05% Dtot

Output Internal Impedance and Offset:  3,3 µH is series with 0,03 Ω . Offset 7 mV max

Frequency Response:

Ref. 1 kHz

Low frequency -1 dB at 20 Hz. Filter attenuation as curve.

High frequency -0,5 dB 20 kHz -3 dB 50 kHz

Signal Input Level:  0,5 V rms ±0,5 dB for 100 watts into 8 Ω . Amplifier loads th input by 20 k Ω  in parallel with 220 pF

Signal Input Slew rate Limit:  0,1V/µS.

Provided the rate of change of input voltages does not exceed this figure which is about ten times the maximum slew rate on a gramophone record and the amplifier is not driven into clipping, then the total of all distortions appearing in the audio range (20 - 20,000 Hz) due to transient or repetitive waveforms with frequency components inside or outside the audio range will be at least 80 dB below full rated power. If the major portion of the input energy is wanted signal then -80 dB (0,01%) represents the maximum possible distortion on programme.

Signal Input Overload:  Instantaneous recovery up to =20 dB overload

Crosstalk (Input loaded by 1 k Ω ):

80 dB at 100 Hz

70 dB at 1 kHz

60 dB at 10 kHz

Hum and Noise:

"A" Weighted:  -96 dB ref full power

Unweighted:  -93 dB ref full power

(15,7 kHz measurement bandwidth)

Protection

The Quad 405-2 is suitable for use under the most arduous music conditions and is electrically protected by current limiters; 8,5 ampers peak current into any load reducing to 3,1 amperes steady state into a short circuit. Shorting both outputs simultaneously for an extended period will result in overheating and eventual breakdown

Stability: Unconditionally stable with any load and any signal

Power Input:  100-120-130 V, 220-230-240 V 50/60 Hz, 30 - 350 watts depending on signal level

Dimensions (W x H x D):  340 x 115 x 195 mm (13,4" x 4,5" x 7,7"). Allow an extra 38 mm (1,5") for plug and socked

Weight:  9 kg (20 lbs)

 

Hafler DH-120 power amplifier

The DH-120 may shatter the illusions of some audiophiles in their search for perfection with ever larger, heavier and more costly amplifiers. It demonstrates once again that quality, not quantity, is the deciding sonic factor. Engineered for adequate power, proper headroom and excellent overload characteristics, together with conservative ratings, the DH-120 surpasses in sound quality many amplifiers of substantially higher advertised output.

To the technically knowledgeable observer, the DH-120 is quite elegant. Its novel drive circuit is extraordinarily linear. Its very low distortion is achieved with relatively little negative feedback. The oversized heat sinks and power supply, the careful selection of critical components for their sonic attributes, and the evident product quality demonstrates our commitment to excellence.

The most important design element is the utilization of power MOSFET output devices MOSFET advantages include self-stabilization  robustness linearity, high speed, vaccum tibe-like characteristics and they require no thermal compensation. Because MOSFETs can handle heavy currents current limiting circuits are not required.

The audio enthusiast will appreciate the extra features which make the DH-120 more versatile than conventional amplifiers. Independent level controls on each channel are valuable for such applications as bi-amplification. For those needing higher power in a small package a back panel switch converts to a bridged mono mode which uses both channels to deliver in excess of 125 watts. If separate speakers are to be used in another area, a second set of speaker terminals is provided. Alternatively, these terminals can be switched to power rear speakers to add ambience recovery to the main system.

Hafler ingenuity has developed a uniquely simple and effective means of recovering heretofore inaccessible sonic details which have been hidden in many recordings and broadcasts. These elusive signals consist of reflected and reverberant sounds which contribute the sense of space and depth in the recording location. When these sounds are reintroduced through loudspeakers placed behind the listener using the Hafler Ambience Recovery System you will find a new sense of immediacy and involvement emerging from many of your familiar recordings.

 

Specifications

Power rating:  less than 0,009% Total Harmonic Distortion at any power level up to 62 watts continuous average power per channel into 8 Ω  at any frequency between 20 Hz and 20 kHz with both channels driven.

Intermodulation DIstortion (SMPTE): less than 0,005% from 1 watt in 62 watts each channel into 8 Ω

Total Harmonic Distortion : 0,002% (8 Ω , 1 kHz)

Frequency Response (at 8 Ω )

At 1 watt :  4 Hz - 200 kHz -3db

At 62 watts :  10 Hz -40 kHz +0 -1/2 dB

Typical Channel Separation: 

20 Hz :  better than 75 dB

1 kHz :  better than 85 dB

20 kHz :  better than 65 dB

Signal-to-Noise Ratio (Unweighted):  exceeded 103 dB referred to 62 watts into 8 Ω

Input Impedance:  22,000 Ω

Input Sensitivity:  11 volts rms for 62 watts into 8 Ω

Damping Factor:  100 to 1 kHz into 8 Ω ; 50 to 10 kHz into 8 Ω

Rise Time:  10 kHz, 45 volts peak to peak square wave, 10% to 90%, 2 µs

Slew Rate:  10 kHz, 45 volts peak to peak square wave, 30 V µs

Semiconductors:  22 Transistors; 4 Power MOSFETs; 23 Diodes; 8 Zener Diodes; 1 Diode Bridge

Power Consumption:  62 watts both channels into 8 Ω , 300 VA

Dimensions (W x H x D):  15-3/8" x 3-1/2" x 9"

Weight:  18 lbs Net