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With our slogan, “Analog still does not reach the limit.” We have commercialized
High end audio equipment to analog disc fans.Our products line-up has been
expanded since 2005 because Model 3 series were added.Besides, we have
been providing the music impression of only analog disc intending by Phase
Tech and gaining support among more a lot of customers.This time, we made
full use of semiconductor-circuit technologies keeping the idea of Phase
Tech, and developed the Phono Equalizer Amplifier of Model 3 series.
Amplifier circuit by semiconductor chip
FULL SYMMETRICAL NON-FEEDBACK CIRCUIT:TM
We aim at the expansion of the ability to express music, and developed and installed newly the full symmetrical non-feedback circuit by a suitable operation of current amplification for the semiconductor. As a result, we have achieved difficult “Rich expression of tone scale, Sense of Energy and High S/N, Compatible prominent spatial expression.” in the amplifier with a traditional transistor device.
The detail of amplifier
The first layer is composed of the voltage current conversion circuit with
extremely low noise by a complimentary connection of complementarity FET
(field-effect transistor).The well-selected device that the operation point
is decided by the self-bias operation does not need the bias circuit, or
there is neither an inflow of the noise nor a deterioration factor of sound
quality, and works the device’s original operation with low noise.
The second layer is composed of the current amplification and the voltage
conversion circuit, and obtains the reproduction characteristic with the
RIAA impedance device connected with the current output point.Therefore,
it is composed of the CR type equalizer circuit without the RIAA deflection
to the super-high frequency and obtains an excellent transient characteristic.In
this circuit, various circuit techniques for operation with high accuracy
are utilized without the influence of the parameter change of the amplification
device that depends on the current conversion error margin and the output
voltage. It is succeeded in obtaining the excellent characteristic that
equals the feed-back amplifier though it is non-feedback amplifier.
The output buffer circuit secures wideband high input impedance by the input bootstrap. The output device by Darlington connection has enough current amplification at the same time, and drives the equipment connected with the next layer strongly.
Realized vibration free, resonance free and interference free
In the phono amp that amplifies a slight signal, it is required realization
of vibration free, resonance free and interference free and simple signal
transmission for keeping signal purity
Mechanical earth
Direct grounding construction of power supply transformer
DIRECT GROUNDING CONSTRUCTION:TM The Rcore type power supply transformer of EA-3 operates with margin by magnetic flux density, and it has been reduced magnetic vibration and generation of leakage flux as much as possible.
In addition, this transformer is assembled directly to planed brass foot through the bakelite board 5mm thickness that is an insulator high electric resistance and reluctance. As a result, the vibration that the power transformer originates is discharged into the earth at once without transmitting to the chassis.

Dual monaural construction
・Except AC1 withdrawing line, it has been composed the
symmetrical dual monaural construction completely,
and achieved the advanced uniformity of right
and left channel.
・It supplies an ideal power without the parameter change due to the power supply load by right and left independent
power supply transformer and shunt type local
power supply. And the channel separation and over 100dB(20Hz-20KHz)
has been achieved by minimizing the loop of the
circuit electric current.

The cassis of structure for vibration free, resonance free and interference
free
・The delicate amplification part mounts sub-chassis floated
in electromagnetism because it doesn't receive the
influence of harmful signal and vibrations
other than the music signal. Consequently, it has been realized the idea
of vibration free, resonance free, interference
free.
・The 1.2mm thick steel plate and the 1.6mm thick one
have been copper-plated for the chassis and top cover,
and done the finish paint. It has been achieved
reduction of magnetic distortion and securing of strength.
It is consisted of the structure for vibration free,
resonance free, and interference free because the front panel
has been made of the aluminum planed 6mm
thick.
Adoption of parts for high sound quality
The metal film resistor is used for all layer of the EA-3 amplification
circuit in order that high stability is obtained at the same time as making
a lower noise. Use the followings for RIAA impedance devise or the main
part of the signal system
Use the followings for RIAA impedance devise or the main part of the signal
system
1) OXYGEN-FREE gilding lead
2) The high sound quality parts have an excellent reputation
like High quality Dipped Mica
Use the followings to compose extremely low noise power supply
1) For the power supply circuit; the first recovery diode with higher typicality to avoid speed decrease of recovery
time in a high electric current domain
2) Low magnifying power, high sound quality electrolytic
condenser
3) Low noise Zenner diode
Installed the active type subsonic filter circuit
It has been achieved a steady reproduction which quality of an analog disk was not controlled because it is installed the actual active type subsonic filter circuit of cut off frequency 20Hz,40Hz (18dB/Oct). Especially, in setting 40Hz subsonic filter, it is large for the effect of the expansion of the howling margin, so that the analog disk playback environment has been expanded to other than the high end fan class.
Specifications
| Model |
MM/MC FULL SYMMETRICAL NON-FEEDBACK CIRCUIT
Phono Equalizing Amplifier |
| CR type |
MM |
MC |
| Input level |
2.5mV |
0.12mV |
| Input Impedance |
47k Ohm |
470 Ohm |
| Gain |
38dB |
65dB |
| S/N ratio in Input |
-124dBV |
-144dBV |
| Maximum Input Capability |
125mV(1kHz) |
6mV(1kHz) |
| Output Voltage |
200mV(1kHz) |
| Rear Curve Deviation |
±0.2dB(20 to 20,000Hz) |
| Output Impedance |
100 Ohm |
| Channel Separation |
100dB and over(20 to 20kHz:MM/MC both) |
| Power Consumption |
7W(100VAC 50〜60 Hz) |
| Dimension |
W 305mm ×H 90mm×D 310mm |
| Weight |
5.1 kg |
| Input and output terminal |
Gold-plated terminal |
| Attachmen |
AC power cable |
Externals image
front rear
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