Phono AmplifierEA-500

Music reality engraved in records which can educe even the artist's passion Separation type phono amplifier (2 units) All-discrete non-feed-back circuits designed newly for all stages

Recieved Prizes

Stereo SoundBEST BUY COMPONENTS 2015-16 Phono Equalizer Amplifier 1st Prize
Ongen PublisingAudio Excellence Award 2016 Silver Prize
Ongen Publisinganalog Grand Prix 2016 Award
Seibundo-shinkosha2016 MJ Technology of the Year Analog Components award
"STEREO" magazineAnnual Best Components 2015 Analog Components 2nd Prize

Product Outline and Concept

Saying "Analog audio products are not fully mastered yet" as our catchword, we have been developing the audio series: the MC cartridge (P-1) released in 2002, the phono amplifier, the pre-amplifier, the main amplifier utilizing a non-feedback circuit, and the passive attenuator.

During these years, the concern with the analog audio playback system has been furthermore enhanced and a variety of new products have been released. We released the new product, EA-500, after waiting until this time that the analog market will become lively; it has been developed newly from the built-in MC transformer to circuits in order to improve the sound quality and functions, aiming for the highest peak of a semiconductor phono amplifier to give you a feeling of a new dimension of an analog disc playback.

Main feature

I. Strong chassis structure consisting of two monaural-block units separated to L/R

The amplifier consisting of the shaved 12mm thick aluminum front panel, 2mm thick copper plating steel chassis base and a 2mm thick aluminum cover has the strong chassis structure; it gives an assured stiffness and reduced magnetostriction.

Furthermore, the sections of equalizers and power supplies of an amplifier separated into L/R support the playback sound by which you can enjoy music expressing the overwhelming liveliness and re-creation of a panoramic stage because of the high resolution and high S/N ratio.

II. The newly designed amplifier circuits featuring V-I/I-V conversion and non-feedback for all stages where all components are discrete

The negative feedback amplifier which holds the popularity of the present amplifiers made of semiconductors or vacuum tubes always compares the input and output signals and this difference (correction signal) is amplified as an input signal; thereby, it can realize high precision amplification at a low cost.

However there is a delay time in principle that cannot be cancelled between the input and output signals and this delay makes it generate a TIM distortion; therefore, this is one of the big reasons why the satisfaction from the audio quality of negative feedback amplifiers cannot be received.

All amplifiers of Phasemation are composed of non-feedback amplifiers made of semiconductors or vacuum tubes.

There is no correction operation like the negative feedback amplifier in the non-feedback amplifier; however, high precision and high technology are required on the components and circuits for being composed.

As a result, the information of the audio sources (records) can be played 100% without dropping it; so the music essentiality can be played because music expressions of an uplifting-feeling, dynamics, shading and so forth are excellent.

In this equipment, the newly designed amplifier featuring the V-I/I-V conversion and non-feedback for all stages, which is composed of carefully-selected discrete components, converts the input signal to the current, performs the equalizing operation to the signal, returns it to the voltage signal, and then outputs it through the cross-multiplying-buffer.

III.Adopting a Variety of Input-Switching Functions

Three lines MC1, MC2, and MM are installed and in addition to RCA terminals, balanced input terminals of the XLR connector are installed for MC1 and MC2.

The MC balance transmission has been supported for inputting the MC signal by incorporating the step-up transformer of special divided-winding structure, which is newly designed in this development to be required for MC balance transmission.

IV. Powerful Capabilities

Mounting a non-feedback type low cut filter of CR2 steps

A bent record disc can be played without audio quality degradation and speaker (woofer) shaking can be prevented.

Adopting the switch for selecting from among three playback curves

In addition to the RIAA characteristics for the stereo system, Mono 1 to be used in the DECCA label and so forth and Mono 2 to be used in the Colombia label are installed for the monaural characteristics.

Music can be played truthfully furthermore than the DECCA label and Colombia label.

V. Adopting High Audio Quality Components

For signal circuits

1: In the RIAA circuits, which strongly influence the audio quality of the phono amplifier, well-established high-audio-quality components are adopted: for example, 1% grade metal-film resistors having a margin for rating and mica capacitors using a silvered mica plate for the dielectric body.

2: In the signal circuits, SILMIC electrolytic capacitors made by ELNA for supporting the audio quality are mounted and 1% grade metal-film resistors are mounted.

For power supply circuits

1: Adopting SiC diodes made by ROHM which is evaluated as high sound quality and small switching noise.

2: Adopting large capacitance capacitors of high-end audio grade having gold terminals to which low resistance electrode foil is plated (made by Nichicon) on the rectifying capacitor.Adopting cerafine capacitors made by ELNA as a decoupling capacitor.

3: Composed of a high speed and extremely low noise power supply circuit because of the shunt regulator in which a feedback circuit is not used by adopting low noise zener diodes.

4: Cancelling a negative effect due to a common impedance of ground by adopting low leakage flux R-core transformers and using them particularly for "+ power supply" and "– power supply" and by rectifying each bridge.

Product Specification

Form Equalizing amplifier featuring V-I/I-V conversion and non-feedback for all stages
Input Type (Cartridge) MM MC
Input Sensitivity 2.5 mV 0.18 mV
Output Impedance for the Cartridge 47 k-ohm or less 1.5 to 40 ohm
Gain 38 dB 61 dB
Input Equivalent S/N Ratio –120dBV –140dBV
Rated Output Voltage 200 mV (1kHz)
RIAA Curve Deviation ± 0.5 dB (20Hz to 20kHz)
Power Consumption 12W (100VAC, 50 to 60Hz)
Dimensions (mm) 210(w) x 103(h) x 355(d)
Weight 5.5kg for each channel unit