stereonomono

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

Single and Dual –Channel Models in Two Power Ranges

Multiple Protection Techniques Avoid Damaged Speakers

Features

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.

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.

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)

Kenwood KA-9100 amplifier

Independent Dual Power Supplies for Both Channels and a Separate Preamplifier Power Supply

Obviously, no stereo imaging can be true unless there is complete channel separation. And one of the drawbacks of conventional amplifiers is that a single power supply creates Dynamic Crosstalk Distortion - a fact first discovered by our own engineers. This form of distortion had been overlooked in conventional measuring methods, which reveal static, rather than dynamic distortion. Following this important discovery, Kenwood's engineers re-designed the power supply into two totally independent supply systems, each with a large separate power transformer, and four large 12,000 µF electrolytic capacitors. A transistorized voltage regulator reduces interference between stages. But not content with this, they also designed a separate power supply for the preamplifier stage to suppress interference between the power amplifier and preamplifier in the same channel. You could, in fact, call this a "three-power supply system"/ the effect is that Dynamic Crosstalk Distortion has been virtually eliminated. Transient response is much improved. Excellent damping yields crisp and accurate sound. And so reproduced sound - particularly in the bass frequencies - is wonderfully rich and clear.

Direct-Coupled Equalizer Section Realizes very High Signal-to-Noise-Ratio:

An exceptionally high 83 dB Signal-to-Noise-Ratio (IHF-A curve) for Phono 1 & 2 is the result of a well designed, three-stage, direct-coupled ICL equalizer section, using FETs. Both phase and transient response are excellent, and distortion is low over a very wide range. Moreover, the use of the Gain selector at the +10 dB position allows a high 73 dB Signal-to-Noise-Ratio: for phono 0,8 mV sensitivity. The maximum phono input level for Phono 1 is a high 250 mV RMS, so there's no danger of overloading when you're playing musical passages of exceptional dynamic range.

Sophisticated Tone Control Give You Real Mastery Over Your Sound

Kenwood's concern for musical purity has given top priority to tone controls, so an elaborate system has been devised to suit all individual listening conditions and needs. BAXANDALL negative feedback low distortion tone controls give you the advantage of great precision and enormous flexibility for adjustment. The control range is 17,5 dB, in 1,5 dB click0stop steps. There are two selectable turnover points, 400 Hz for bass and 3 kHz for treble. These let you precisely compensate for your room characteristics. Moreover, the tone defeat is not simply a tone-out switch, but a true bypassing circuit, so that distortion and channel crosstalk are eliminated and tonal quality retains its excellence.

Two Steep Slope Filters

Here again, a bypassing defeat circuit is used to minimize distortion. These two filters have a characteristic steep slope of 12 dB/oct, allowing the music to pass freely while cutting out interference. There is a high filter with a cut-off point of 8 kHz, and a subsonic filter with a cut-off point of 18 Hz. High frequency noises such as record scratch, and low or subsonic influence generated by record warp or turntable rumble are effectively eliminated.

Unique tape-Through Circuitry

Kenwood's versatile tape circuitry permits simultaneous recording of two tape decks, and monitoring of both. There's also inter-tape dubbing both ways. And there's our now familiar tape-through facility that lets you listen to a different source while recording or dubbing takes place.

The Simpler The Circuitry The Better The Sound

Many circuitry design improvements have been made to enhance tonal quality. Some of them are major developments such as our DC power amplifier and dual power supplies, developed at our laboratories. With a full ICL (Input Capacitor-less) system, ICL circuitry is used in both the crucial equalizer and tone control sections. For all these circuits, inputs are directly connected to the unit without having to pass through input capacitors which produce distortion. Moreover, if you look inside the KA-9100 you'll probably be surprised at how "clean" it looks. This is not just cosmetic treatment, however. We know that there are clear-cut audio advantages in reducing wiring, and by making direct connections to the printed circuit boards. The more wiring there is, the more chance for hum and noise and various kinds of distortion that affect the sound. One example is the speaker selector. Instead of long wiring leading to the back panel and picking up noise on the way, there's a long shaft, and the actual selector is next to the speaker terminals. There are many other examples of this wire elimination to be seen, all contributing towards the refinement of that special Kenwood tonal quality.

Professional, Full-Scale Attenuator Type Volume Control With Gain Control

The dual combination of a tree-step (+10db, 0, -10 dB) Gain control and full-scale attenuator type 32-step volume control provides you with highly accurate volume attenuation. This means that the entire audible range is increased or reduced logarithmically. Your sound, even at low levels, remains naturally balanced. The Gain control also is highly useful when using tape decks and turntables which need some compensation for sensitivity low throughout the attenuation range. As you can see on the back page, other comparable models rarely maintain this low residual noise level over the whole volume range.

Two-Step Loudness Control

This loudness selector boosts the low range frequencies below two levels, giving you more control over which levels need more boosting. At -30 dB volume level, a 10 dB boost is made at 100 Hz or 30 Hz. You'll find this gives your ear the necessary compensation when listening at very low volume.

Pre-Out and Power-In Terminals

A thoughtful feature for the more professionally minded in the selector that allows the DC power amplifier and full ICL control amplifier to be used separately for multi-amp hi-fi systems.

Twin Power meters

These days, audiophiles are interested in every aspect of their components, and such features as accurate power monitors are essential. Kenwood's power meters are of a logarithmic compression type with two selectable ranges: 0,01W - 100 W and 0,01W -0,3W (for low level monitoring).

Specifications

Power Amplifier Section

Power Output: 90 watts per channel, minimum RMS, at 8 Ω. From 20 Hz to 20 kHz with no more than 0,03% Total harmonic Distortion:

Both Channel Driven :

95 + 95 watts (8 Ω) at 1,000 Hz

110 + 110 watts (4 Ω) at 1,000 Hz

Dynamic Power Output: 470 watts (4 Ω)

Total harmonic Distortion:

0,03% at rated power into 8 Ω

0,01% at 1 watt into 8 Ω

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

0,03% at rated power into 8 Ω

0,01% at 1 watt into 8 Ω

Power bandwidth: 5 Hz to 60,000 Hz

Frequency Response: DC to 100,000 Hz +0 dB. -1 dB

Signal-to-Noise-Ratio: 115 dB (short circuited)

Damping Factor: 50 at 8 Ω

Input Sensitivity/Impedance: 1,0 V/ 50 kΩ

Speaker Impedance: 4 Ω to 16 Ω

Pre-Amplifier Section

Input Sensitivity/Impedance

Phono 1 : 2,5 mV/50 kΩ

Phono 2 : 2,5 mV/50 k Ω

Tuner : 150 mV/50 kΩ

Aux : 150 mV/50 k Ω

Tape A, B : 150 mV/50 kΩ

Signal-to-Noise-Ratio:

Phono 1 : 83 dB

Phono 2 : 83 dB

Tuner : 100 db

Aux : 100 dB

Tape A, B : 100 dB

Maximum Input level Phono 1 : 250 mV 9rms) T.h.d 0,03% at 1,000 Hz

Output/ Level Impedance

Tape Rec (pin) : 150 mV/450 Ω

Tape Rec (DIN) : 30 mV/80 k Ω

Pre Out : 1 V/330 Ω

Frequency Response:

Phono : RIAA standard curve +0,2 dB, -0,2 dB

Aux. Tape : 7 Hz - 50 kHz +0 dB, -1 dB

Tone Control

Bass ; ±7,5 dB at 100 Hz (turnover at 400 Hz)

Treble : ±7,5 dB at 10 kHz (turnover at 3 kHz)

Loudness Control (-30 dB): +10 dB at 100 Hz; +10 dB at 30 Hz

Subsonic Filter: 18 Hz. 12 dB/oct.

High Filter ; 8 kHz, 12 dB/oct.

General

AC Outlets: 2 switched, 1 unswitched

Power Consumption: 660 watts at full power

Dimensions (W x H x D): 430 x 149 x 384 mm (16-15/16" x 5-7/8" x 15-1/8")

Weight (net): 16,7 kg (36,8 lbs)

Kenwood KR-3200 receiver

Kenwood KR-3200

FM/AM Stereo Receiver

Stereo Sophistication for Music Lovers on a Budget

For a stereo receiver with audiophile sophistication at a moderate price, look no farther than the Kenwood KR-3200. This remarkable unit delivers ample power to drive two sets of stereo speakers. It provides a control center for a complete stereo system, including Phono, Auxiliary and Tape Deck. It also incorporates many of the same fine features found on Kenwood’s far more expensive units, to give you operating convenience and flexibility. Like all fine Kenwood products, the KR-3200 reflects Kenwood's meticulous engineering and stringent quality control in its high performance level and extraordinary dependability. In every respect, the Kr-3200 proves itself a remarkable stereo value.

Newly-Developed DSD Circuitry – Kenwood’s exclusive Double-Switching Demodulator in the MPX circuit appreciably improves stereo separation. A new block filter design efficiently reduces beat interference and intermodulation distortion due to carrier leakage, greatly improving FM de-emphasis characteristics.

Super Low-Noise Preamplifier – Kenwood incorporates new PNP silicon low-noise transistors in the preamp stage to assure low-noise performance and circuit reliability.

Power Amplifier Section – The KR-3200 boasts a wide frequency response with exceptional flatness to deliver stereo reproduction on the highest fidelity. Damping factor is excellent, especially at the lower frequencies.

Linear Frequency Dial Scale – Because the KR-3200 employs a linear frequency variable capacitor, the FM dial scale is equally graduated from 88 to 108 MHz, allowing quick, accurate tuning from one end of the dial to the other.

Large, Luminous Tuning Meter – An extra-large, bright Signal Strength Meter provides an easy read-out of optimum reception point for easy tuning accuracy.

One-Touch Speaker Terminals – Connecting the two sets of stereo speakers is as easy as pushing a button with these newly-designed, short-circuit-proof speaker connectors.

Step-Type Tone Controls – Precise and resettable tonal balance can be achieved by means of Bass and Treble Tone Controls calibrated in 2 dB increments from +10 dB to -10 dB

Other Features – Loudness Control; Noise Filter; Tape Monitor; Front Panel Headphone Jack; 300 and 75 ohm antenna impedance

Specifications

FM Tuner Section

Sensitivity (IHF): 2,3 µV

Quieting Slope: 48 dB at 5 µV ; 60 dB at 10 µV ; 63 dB at 50 µV

Signal-to-Noise-Ratio: 63 dB

Capture Ratio (IHF): 3,5 dB

Selectivity Ail. Ch (IHF): 50 dB

Frequency Response: 20 – 15,000 Hz (+0,5 -2,0 dB)

Stereo Separation: 53 dB at 1 kHz; 20 dB at 10 kHz

Total harmonic Distortion: (at 400 Hz, 100% Mod.)

Mono : 0,5%

Stereo : 0,9%

Image Rejection: 60 dB

IF Rejection: 90 dB

Harmonic Spurious Rejection: 80 dB

AM Suppression: 60 dB

Sub-Carrier-Suppression: 45 dB

Antenna Impedance: 300 Ω and 75 Ω

AM Tuner Section

Sensitivity (IHF): 24 µV

Signal-to-Noise-Ratio: 45 dB at 1 mV input

selectivity (IHF): 30 dB

image Rejection Ratio: 45 dB

IF Rejection: 35 dB

Antenna: Built-in ferrite bar antenna, External antenna terminals

Amplifier Section

Continuous Power Output (RMS)

Both Channels Driven Simultaneously

27 watts (13,5 + 13,5) at 8 Ω from 50 Hz – 20 kHz

34 watts (17 +17) at 8 Ω 1 kHz

40 watts (20 + 20) at 4 Ω 1 kHz

Each Channel Driven

24/24 watts at 4 Ω at 1 kHz

18,5/18,5 watts at 8 Ω at 1 kHz

Dynamic Power Output (IHF)

Both Channels Driven

60 watts at 4 Ω

42 watts at 8 Ω

Total harmonic Distortion:

Less than 1,3% at rated output

Less than 0,2% at -3 db

Intermodulation Distortion:

Less than 1,3% at rated output

Less than 0,2% at -3 dB

Frequency Response:

High Level Input: 25 – 35,000 Hz (±2 dB)

Power Bandwidth (IHF): 25 – 25,000 Hz

Input Sensitivity/Impedance

Phono : 3 mV/50 k Ω

Aux : 180 mV/30 k Ω

Tape Play : 200 mV/45 k Ω

Hum and Noise

Phono : 63 dB

Aux : 75 dB

Tape Play : 75 dB

Output Voltage

Tape Rec : 180 mV

DIN Connector : 30 mV

Tone Controls

Bass : ±10 dB at 100 Hz

Treble : ±10 dB at 10 kHz

Loudness Control:

± 10 dB at 100 Hz

+0 dB at 10 kHz

Noise Filter: -10 dB at 10 kHz

Damping Factor (8 Ω ): 50

Speaker Impedance: 4 to 16 Ω

General

Switches

Speakers: Off, A, B, A + B

Selector: AM, FM, Phono, Aux,

Mode: Mono-Stereo

Others: Tape Monitor, Noise Filter, Loudness

AC Outlets: 1 switched, 1 unstitched

Power Voltage: 110 – 120 V AC, 50/60 Hz

Power Consumption: 85 watts at full power; 20 watts at no signal

Dimensions (W x H x D): 17-1/8” x 5-3/4” x 13-5/8”

Weight: 18 lbs

JVC JT-V11 tuner

Here’s a new JVC high-fidelity tuner to make an ideal mate for any of the JA-S stereo integrated amplifiers, particularly the JA-S11. Add a turntable and pair of speaker systems and your audio system is ready to move you into an exciting musical adventures. Among the many first-class features of this well-built model are its big twin tuning meters.

Wide 240 mm Tuning Dial

we are able to equip our tuners with wide tuning dials because our tuning mechanisms are precision designed to guarantee accurate station indication and a smooth “feel” . JVC knows how important easy-to-read dials can be to your radio listening pleasure. So we’ve made extra sure that the 240 mm (9-7/16”) wide dial on the JT-V11 is accurately calibrated and that the heavy flywheel/tuning knob mechanism offers a good feel as well.

Twin Tuning Meters

station selection is quick and easy because this unit is equipped with two meters – one for signal strength and the other for centre of channel in FM. Both are very large and well illuminated. For accuracy, they feature tested circuits, so that you’ll never be fooled by false indication.

Switch

One switch does it all. We’ve combined the FM Muting function with the mono-auto FM selector for user convenience. Setting the switch to FM Auto automatically engages the FM muting circuit to end inter-station noise you hear while tuning a station. Stations with weak signals and little hi-fi quality are effectively cut out; you only hear FM stations with sufficient hi-fi parameters.

Dependable Electronics

We’ve employed the best of our electronics techniques in designing the JT-V11. A total of three high-integration ICs – one each for FN IF, FM MPX (Multiplex) and AM - are employed. Total circuit dependability is the key advantage of this IC construction. Additionally a PLL (Phase Locked Loop) FM MPX is used for wide stereo separation. Then, an FM IF Filter – a new 4-resonator single-unit ceramic filter – that improves selectivity and hi-fi specifications.

Specifications

FM Tuner Section

Tuning Range: 88 MHz – 108 MHz

Usable Sensitivity (IHF): 1,9 µV

Sensitivity for 50 dB S/N (Stereo): 40 µV

Distortion

Mono : 0,2% (1 kHz )

Stereo : 0,4% (1 kHz )

Signal-to-Noise-Ratio:

Mono : 72 dB

Stereo : 50 dB

Selectivity: 60 dB

Capture Ratio: 1,0 dB

IF Rejection: 90 dB

Stereo Separation: 35 dB (at 100 Hz); 40 dB (at 1 kHz); 30 dB (at 10 kHz)

Frequency Response: 30 Hz – 12 kHz +0,5 dB , -2,5 dB

Output Level: 650 mV (400 Hz, 100% Mod.)

AM Tuner Section

Tuning Range: 525 kHz – 1605 kHz

Usable Sensitivity: 300 µV/m (Bar antenna); 50 µV (External antenna)

Signal-to-Noise-Ratio: 50 dB

Distortion : 0,5%

Selectivity : 30 db

General

Dimensions (W x H x D): 390 x 152 x 358 mm (15-11/32” x 6” x 14-3/32”)

Weight: 5 kg (11 lbs)

JVC A-X2 amplifier

Super-A Integrated Amplifier

For years, audiophiles have praised the purity, depth and naturalness of Class-A amplifiers.

But they haven't been wild about the heat, weight, power limitations and high cost that go hand-in-hand with Class-A's low efficiency and high idling currents. That's why Class-A has remained a rare, esoteric design chosen by the few who were willing to pay for its fidelity and put up with its limitations.

JVC Super-A design brings together the purity of Class-A and the efficiency of the more common Class-AB. By eliminating most of the measurable switching and crossover distortion. Super-A achieves the kind of sound that has distinguished Class-A designs of the past.

At the same time, Super-A is as efficient as Class-AB, so there are no heat and weight problems which also drive up the cost of conventional Class-A. and JVC Super-A amplifiers have no transient intermodulation distortion (TI) thanks to very wide bandwidth capabilities. What's more, the A-X2 Zsuper-A amplifier shown here includes a 5-band graphic equalizer for both normal playback and recording EQ. LED power meters, "direct power supply" which yields high damping factor at all frequencies, and JVC's Triple Power protection system.

All this comes with plenty of power behind it; 40 watts per channel continuous (RMS) power into 8 ohms, from 20 to 20,000 Hz, with no more than 0,007% Total Harmonic Distortion:.

Specifications

Output Power (Both channel driven):

40 watts per channel, min. RMS into 8 ohms, from 20 to 20,000 Hz, with no more than 0,007% Total harmonic Distortion

42 watts per channel into 8 ohms at 1 kHz

Total Harmonic Distortion::

0,007% at rated output, from 20 - 20,000 Hz, 8 Ω

0,003% at rated output at 1 kHz, 8 Ω

Intermodulation Distortion: 0,007% at Rated output,, * Ω

Power Bandwidth: 10 Hz - 30 kHz (IHF, both channels driven, 8 Ω, 0,02% Total harmonic Distortion:.)

Frequency Response: 10 Hz - 100 kHz +0 -3 dB

Damping Factor: 50 (1 kHz, 8 Ω)

Tone Controls: S.E.A.

Center Frequency: 40; 250; 1 k; 5 k; 15 kHz

Control Range: ±12 dB

Input Sensitivity/Impedance

Phono : 2,5 mV/47 kΩ

Tuner, Tape, Aux ; 150 mV/40 kΩ

Rec. Output Level: 150 mV

Phono EQ. Deviation: ±0.5 dB (20 Hz - 15 kHz)

Phono Overload: 150 mV (1 kHz)

Signal-to-Noise-Ratio:

Phono : 73 dB (new IHF)

Tuner, Tape, Aux : 77 dB (new IHF)

Loudness Control (Volume Control at -30 dB position): +6db at 100 Hz; +4 dB at 10 kHz

Dimensions (W x H x D): 420 x 120 x 329 mm (16-1/2" x 4-11/16" x 12-5/16")

Weight: 6,6 kg (14,6 lbs)

Akai X-200D reel-to-reel

Three motors Auto-reverse custom deck

Model X-200D - this smartly designed three motors, Auto-reverse custom deck offers you superb stereo hi-fi tape recording and automatic reverse playback.

Outstanding Features:

4-track stereo/monaural recording and playback. For playback, the X-200D requires an external power amplifier and speakers

3 speeds - 1-7/8; 3-3/4; and 7-1/2 ips

3 heads - Erase, Recording/Playback and bias heads. Cross-field head System

3 motors - A hysteresis synchronous 3-speed motor for capstan drive. Two 6-pole eddy current out-rotor motors for supply and take-up reel drive

Wide Cross-field frequency response

Solid state pre-amplifier with two integrated circuits

Sensing tape continuous reverse [Auto, reverse]

Manual revers

Shield type head for high Signal-to-Noise-Ratio:

Two lever system ensures dependable and durable operation

Track selector for simple selection between stereo and monaural

Slide-type record level controls

100 kHz biased for FM multiplex recording

Automatic stop/shut off, Instant stop control with start button

Automatic pinch wheel release

Tape speed equalizer

Tape lifter in fast forward and rewind operation

DIN jack with selector switch for High/Low input

Stereo headphone jack

4-digit index counter with reset button. Twin type VU meter with record indicator lamp

Fine oil-finished wooden cabinet

Universal voltage selector [from 100V to 240V. 50/60 Hz]

Cross-Field Head

On conventional recorders the signal and bias are applied to the same recording head. Therefore the frequencies recorded, especially the high frequency component of the recorded signal tend to be attenuated or erased by the effect of the bias field.

On the exclusive Akai Cross-Field Head which was developed by Akai for practical use the signal and bias heads are mounted in opposition with their centers slightly off. As the recorded signal is entirely unaffected by the prevailing effect of the bias field, the tape can be recorded over the entire frequency spectrum with maximum fidelity.

Sensing Tape Continuous Reverse

Automatic reverse with metallic sensing tape is used for playback only. Reverse operation will occur when metallic sensing tape on pre-recorded tape makes contact with the Sensing Pin. Put metallic sensing tape at the desired reverse point on shiny side of the pre-recorded tape and another metallic sensing tape at the desired reverse point on dull side of the pre-recorded tape. The X-200D will then give continuous playback in both directions between two points.

Manual Reverse

The X-200D may be manually reversed by pushing the Reverse Buttons.

Solid State Pre-Amplifier with Two Integrated Circuits

X-200D’s solid state pre-amplifier uses special two Integrated Circuits developed by Akai

Specifications

Tape Speeds : 1-7/8; 3-3/4 and 7-1/2 ips

Max. reel Size: 7” reel

Fast Forward and Rewind Time

75 seconds for 1,200 ft. tape at 50 Hz

60 seconds for 1,200 ft. tape at 60 Hz

Motors :

Hysteresis synchronous 3-speed motor for capstan drive.

Two out-rotor motors for supply and take-up reel drive

Heads : Record/Playback Head: Erase and Bias heads

Wow and Flutter:

7-1/2 ips : less than 0,08% RMS

3-3/4 ips : less than 0,12% RMS

1-7/8 ips : less than 0,20% RMS

Frequency Response:

7-1/2 ips : 30 – 20,000 Hz ±3 dB

3-3/4 ips : 30 – 19,000 Hz ±3 dB

1-7/8 ips : 30 – 9,000 Hz ±3 dB

Signal-to-Noise-Ratio: : better than 50 dB

Total harmonic Distortion: : within 2% at 1,000 Hz 0 VU recording

Input Level

Mic : better than 0,5 mV

Line : better than 50 mV

DIN : better than 5 mV (Low), >50 mV (High)

Output Level

Line : VU (1,23 V)

DIN : 0,4 V

Equalization: Correct equalization for playback of tapes recorded to the NAB curve

Recording Bias Frequency: 100 kHz

Recording Level Indicator: Twin type VU meter

Recording System: 4-track stereo/monaural Cross-Field bias system

Semiconductors: 14 Transistors ; 2 ICs ;

Power Supply: AC 100 to 240 V, 50/60 Hz

Power Consumption: 8 - 90 VA

Dimensions (W x H x D): 358 x 358 x 227 mm (14” x 14” x 8-7/8”)

Weight: 17 kg (37,4 lbs)

Akai 1710W reel-to-reel

Akai 1710W Mignon Stereo Tape Recorder

Creating a delightful mood of stereo music around you

New compact style with oil-finished wooden cabinet complements your hi-fi set or other furniture

Rugged construction assures trouble-free operation

Tape cleaner keeps tape and heads free of dust and Oxide powder, and prevents annoying tape squeak.

Outstanding features

4-track stereo/monaural recording and playback

3 Speed, 1-7/8; 3-3/4 and 7-1/2 ips (15 ips optimal)

Shield type head for high s/n

Two lever system ensures dependable and durable operation

Track selector for simple selection between stereo and monaural

Automatic shut off

Instant stop control

Tape cleaner

Tone controls

Speaker switch

Tape lifter in fast forward and rewind operation

4 hours maximum stereo recording capacity with a 1,200 foot tape

Two built in 5” x 7” speakers

DIN jack, Stereo headphone jack

3-digit index counter with reset button, 2 VU meters

One piece front panel and fine oil-finished wooden cabinet

Vertical and horizontal operation

Universal voltage selector (from 100 V to 240 V, 50 or 60 Hz)

Specifications

Tape Speed : 1-7/8; 3-3/4 and 7-1/2 ips

Tape Speed Deviation: within ±3% at all tape speeds

Fast Forward and Rewind Time

150 seconds for 1,200 ft. tape at 50 Hz

120 seconds for 1,200 ft. tape at 60 Hz

Monitor System: Can be monitored the program being recorded by using a stereo headphone

Motor: Condenser starting induction two-speed motor

Horse Power: 1/100 HP

Power Ratio: 70%

Revolution

2,900 to 1,450 rpm at 50 Hz

3,480 to 1,740 rpm at 60 Hz

Reels Used: 7” – 5” – 3” reels

Heads

Rec/Play Head: Inline 4-track stereo/monaural

Gap : 4/1000 mm

Impedance: 3,600 Ω at 1,000 Hz

Erase Head: Inline 4-track stereo

Gape: 0,1 mm

Impedance: 3,6000 Ω at 90 kHz

Record Level Indicator: Vertical indication model “A” VU meter

Wow and Flutter:

7-1/2 ips : less than 0,18% RMS

3-3/4 ips : less than 0,25% RMS

1-7/8 ips : less than 0,35% RMS

Frequency Response:

7-1/2 ips : 40 – 15,000 Hz ±3 dB

3-3/4 ips : 40 – 12,000 Hz ±3 dB

1-7/8 ips : 40 – 6,000 Hz ±3 dB

Signal-to-Noise-Ratio: better than 50 dB

Total harmonic Distortion: within 3% at 1,000 Hz 0 VU recording

Crosstalk :

Monaural : less than -55 dB

Stereo : less than -43 dB

Erase Ratio: less than -70 dB

Insulation Resistance: better than 50 M Ω

Insulation Durability: 1,000 V, AC for more than one minute duration

Line Output: 2,5 V at volume maximum (250 Hz, 0 VU recorded tape used)

Impedance: 82 k Ω

Main Output: 4 W at music power per each channel total 8 W

Impedance: 8 Ω

DIN Output: 2,5 V at Volume maximum

Impedance: 82 k Ω

Line Input: 150 mV

Impedance: 130 k Ω

Mic Input: 3 mV

Impedance: 30 k Ω

DIN Input: 20 mV

Impedance: 36 k Ω

Recording System: In-line 4-track stereo, monaural recording

Playback System: In-line 4-track stereo, monaural playback

Transitor Used: 2SC650 (x2); 2SC-458LG [C, D] (x2)

Tube Used: 12AT7 (x1); 6AR5 (x2); 6CA4 (x1)

Germanium Used: IN-34A (x2)

Power Supply: AC 100 to 240 V, 50/60 Hz

Power Consumption: 80 VA

Dimensions (W x H x D): 345 x 360 x 190 mm (13-1/2” x 14” x 7-1/2”)

Weight: 15 kg (33 lbs)

Jensen SG-300 Sigma speaker

Jensen brings you an advanced 12" version of the famous Triaxial loudspeaker

Many years ago Jensen introduced the G-610 Triaxial 3-way loudspeaker, three acoustically and electronically independent loudspeakers in one unitary assembly. It made history as the first 3-way system and embodied the first horn-loaded compression driver supertweeter to be used in a commercial high fidelity loudspeaker. When this 15" speaker was installed in a large enclosure,, the sound was truly awe inspiring.

Now Jensen has created the SG-300 Triax® . It is scaled down in dimensions and will go in a compact shelf-size enclosure. It retains all of the important original concepts, is even more advanced in its use of the Flexair® high-compliance long-travel surround and Syntox-6 magnetic structure in the woofer.

The Jensen Sigma Series of high fidelity unitary loudspeakers offers a comprehensive range of six 12" and three 8" models to suit most every unitary application. This brilliant Series of loudspeakers embodies every advance in acoustic design, every wanted feature of convenience, performance and high reliability.

SG-300 Triax® 12" 3-way unitary loudspeaker

Jensen's newest exclusive, a true 3-way 12" unitary hi-fi speaker. The Flexair® woofer and Syntox-6® magnet structure produce rock-bottom bass to 20 Hz. A low-distortion compression midrange uses the woofer cone as its horn mouth. The cast support bar contains a new horn-loaded compression super-tweeter which delivers response well past 20 kHz.

Specifications:

Nominal Size: 12”

Power Rating: 30 watts

Frequency Range: 20 – 20,000 Hz

Impedance: 8 ohm

Crossover: 600 Hz, 4000 Hz

Balance Control: Mid/High Frequency

Woofer Resonance: 25 Hz

Dimensions: 12-3/8” diameter; 8-1/8 deep

Connections: Push Type Binding post

Weight: 15 lbs (shipping)

Jensen HS-2 headphones

Jensen HS-2

These unique stereo headphones bring an exciting new dimension to your favorite mono or stereo recordings. You’ll marvel at the smooth, full range, undistorted output.

comfortable to wear, easy to listen to.

Soft foam cushions provide feather weight comfort and preserve the undistorted bass response without pressure. Add pleasure to your personal stereo listening.

Jensen Model HS-2 Stereo Headphones bring an exciting new dimension to your favorite recordings. Unusually smooth full range undistorted output set these headphones apart. Soft foam cushions provide feather weight comfort and preserve the undistorted bass response without pressure. Response is true, complete, distortion-free from below 20 to 17,000 cycles.

HS-2 Stereo Headphones may be connected to any stereo or mono system. A full 8-foot input cable is conveniently located to the rear of the left phone. Of course, it carries the Jensen 5 year hi-fi guarantee. Suggested resale price $24,95.

Specifications

Drivers: High-Compliance, Maisture resistant diaphragm

Frequency Range: Below 20 Hz to 17,000 Hz

Power Requirements: comfortable listening with 1 milliwatt; loud listening with 10 milliwatts

Impedance: 4 Ω each channel (may be connected to 4- , 8- , or 16- Ω amplifier outputs)

Terminals: Standard 3-conductor headphone plug

Cord: 8’ long

Weight: 16 oz (Net); 2 lbs (Shipping)

AKG K-240 headphones

AKG K-240

Among AKG patents, none is more significant than the Passive Diaphragms found in K-240 (K-340, K-3) models. Mounted within each earpiece, they perform two distinct functions when activated by sound waves. – They are acoustically transparent above 200 Hz, and one listens in a virtually “free field”. Unwanted mid- and high-frequency peaks and valleys of conventional circumaural (closed) headphones are eliminated. Sound enters the ear in a “normal” manner as in supra-aural (open) headphones. –Below 200 Hz, combined with acoustical “screens”, they form a controlled, damped vent to flatten out any bass peaks, thus eliminating boominess common in most circumaural headphones, and extends linear response lower than would otherwise be possible in supra-aural headphones. The result is pure listening pleasure, you hear tone gradations often lost in loudspeakers or in the listening room environment.

The Complete Free-Field Headphone

The K-240 is the first totally sound and comfort engineered headphone incorporating all the features necessary for complete listening enjoyment; accurate stereo imagery, outstanding fidelity of reproduction at all listening levels, extreme comfort with virtually no fatigue under prolonged use, and uncomplicated ease of use.

The Passive Diaphragms

in the K-240, the compliance of the passive diaphragms, combined with acoustical resistances, forms a controlled, highly damped vent to counteract and flatten out the resonant peak. This eliminates boominess down to a lower frequency than would otherwise be possible

The K-240’s unusual construction improves wearing comfort, reduces weight, and totally eliminates annoying user adjustments. Its soft, perforated support band shapes easily to the head and simultaneously self-positions the headphone driver elements comfortably on the ears. At the same time, AKG’s exclusive Cardan (universal-joint gimbal) earpieces automatically, independently, and correctly self adjust to each ear for optimum listening contact.

K-240 utilizes Passive Diaphragms and acoustic “screens” for controlled response and “free field” realism. Dynamic transducers provide accurate reproduction and high output. Universal gimbal (cardan) suspension for each earpiece with self-adjusting headband is comfortable to wear over long periods. Favourite of recording and broadcast studios.

Common to all AKG headphone designs, the circumaural K-240 possesses outstanding features which increase wearing comfort, fit and flexibility of the headphone. Unique self-adjusting headband and cardan-swivels locate the earpieces precisely and accurately regardless of head or ear shape, long-term wearer fatigue is eliminated. Weight is distributed uniformly over wide headbands. In environments where noise could be a problem, circumaural headphones are an ideal selection. And remember, the patented “Passive Diaphragms” yield qualities equal to the most natural listening environment.

Specifications:

Operating Principle: Dynamic moving coil

Frequency Range: 15 – 20,000 Hz

Sound Pressure Level (thd 1,0%)

108 dB (at 100 – 2,000 Hz)

112 dB (at 1,000 Hz)

Sensitivity: 20 µb/V

Normal Listening-Level Requirements: 0,5 V (0,4 mW) for 94 dB SPL (=10 uv b)

IHF Sensitivity: 4V (27 mW) for 112 dB SPL (=80 µb)

Nominal Impedance: 600 ohm per system

Maximum Continuous Input: 11 V (200 mW) =121 dB SPL (per channel)

Total harmonic Distortion: (at 95 dB SPL): 0,3%

Weight: 224 g (7,9 oz) without cable

Cable Length: 3 m (10 ft) ¼ inch phono plug

Audio Technica AT-701 headphones

Products of one of the world’s best equipped laboratories for the development of audio and acoustic devices, Audio-Technica headphones bring entirely new levels of reproduction quality and listening enjoyment to the headphone user. Beginning with the acoustic fundamentals, Audio-Technics engineers have brought refreshingly new insights into every aspect of headphone performance.

It is important at the beginning to understand that the design of most conventional headphones is fundamentally incorrect. Most headphones seem to be designed first from a visual standpoint. They are provided with large, impressive ear cups and elaborate-looking headbands. The result is considerable unnecessary weight, an extreme sense of discomfort after only short listening intervals and, most importantly, an unnatural, highly colored sound. The large impressive-appearing ear cups, alas, contribute to severe resonant peaks in frequency response and closed-in-effect.

Audio-Technica headphones are dramatically different from conventional headphone designs. First, much attention has been paid to keeping total weight extremely low. Likewise the headband is designed to keep the earphones securely in place, yet imparting a minimum of pressure to the head. As a result, Audio-Technica headphones may be worn in complete comfort for any desired period of time.

The acoustic properties of Audio-Technica headphones are likewise highly advanced. The diaphragms are bi-polar radiators. The ear cup provides no restriction to the free movement of the diaphragm; there is no trapped volume of air behind the diaphragm. As a result, higher diaphragm velocities are attained, providing improved transient response and reduced distortion. An “open” feeling is immediately experienced when listening to this type of headphone making conventional, closed-back headphones seem closed-up by comparison. Ambient noise is reduced, permitting complete involvement with the program material, yet the listener is never totally out of contact with the outside world.

Audio-Technica headphones may be used with any standard amplifier or receiver, and dynamic models are provided a convenient coiled cord. Ear pads may be detached readily for replacement if desired.

Model AT-701 Dynamic

Unusually Flat, wide-range response is provided in a model AT-701, also employed a dynamic driver unit of 47 mm diameter. The non-resonant, thermos-formed, polymer diaphragm material offers both stiffness and extremely low mass. Copper plated aluminium wire is used for the voice coil, for minimum mass and excellent electrical characteristics.

Specifications

Frequency Response: 30 – 20,000 Hz

Impedance: 4 – 16 ohms

Sensitivity: 97 dB ±2dB/mW at 1 kHz

weight: 6,3 oz

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)

Pagine

Search this site

Yamaha P-2250 dual-mono power amp

Yamaha P-2150 dual-mono power amp

Kenwood KA-9100 amplifier

Kenwood KR-3200 receiver

JVC JT-V11 tuner

JVC A-X2 amplifier

Akai X-200D reel-to-reel

Akai 1710W reel-to-reel

Jensen SG-300 Sigma speaker

Jensen HS-2 headphones

AKG K-240 headphones

Audio Technica AT-701 headphones

Yamaha P-1250 monaural power amp

Followers

Contributors

Top Five

visitors

Modulo di contatto

Pagine

Search this site

Followers

Join this site

Contributors

Top Five

visitors

Modulo di contatto

stereonomono