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I would like to express concerning one audio of hobby

Configuration (Placement)

Turntable: Pioneer MU-7 (synchronous and rim-drive)

Arm: Technica 1005MK2 (Airlift it is attached) 

Needle: Matsushita 205MK2 205CMK2-X, Ortofon LM20

Pre amplifier: Original (Kaneda Type)

SACD/DVD player: MARANTZ DV-8300, DENON DBP-1611UD

Cassette Recorder: AKAI GX-93

Channel divider: Original 3way3channel, 24dB/oct

Front Main amplifier: LUX A501 (- 560Hz), LUX A501 (370Hz – 5.4KHz), LUX A501 (5.4KHz -)

Sub Main amplifier: Original 6 channel

FM/AM tuner: Matsushita ST-3600

HDMI decoder: Onkyo SA-205HDX (Remodeling)

Surround decoder: Original QS/SQ logic decoder, Sansui QSD-1, Sony SQA-2030 (Remodeling)

Main speaker: JBL 2215A (- 560Hz), JBL LE85 + Coral AH500(horn) (370Hz – 5.4kHz), Foster T925 (5.4kHz -)

Surround speakers (front and rear): WAVECOR WF118WA01 (- 2KHz), DAYTON ND20FB-4 (2KHz -)

Headphone: Stax SR-X + SRD-7, Sennheiser HD-414

Source

The motor is synchronous type (Unlike the servo motor, life is a permanent, merit is a breakdown that is totally unrelated).  SACD is a Marantz DV-8300, because of a read error has increased, is in transition to DENON DPB-1611UD.

Pre amplifier

Noise due to leakage flux of the power transformer (by layout miss) occurs to dead copy of the C22. Also occurred (that can not be avoided therefore Tube) also microphonic noise (Howling). As a result, S/N is poor and can not withstand practical use, so retired immediately after completion. Inside that upside and downside. The circuit.

Successor, now the bosom oak it is, Kaneda system. The inside and circuit. Nearly 40 years it was active service. Recently, producing the operational amplifier type EQ amplifier, you saw, but the sound quality does not completely serve to the Kanada system of discrete system, active service of Kanada type may continue for a while.

Channel divider

Channel divider (for 3-way multi-system) that was recently made​​. The inside and circuit. Also put low boost function.

Main amplifier

First vacuum tube type amplifier and DC amplifier handmade do try, but Speaker about handmade merit be LUX A501 kit and immediately after sell do A501 finished product (price not change, solder definite), Multiple constitution. You do not express details, but as for the A501 the one where the seal dropped the punching metal section weakly is better. And, because of the variable resistor for input level adjustment is high, hum so enter, 100k ohm is replaced with a 20k ohm. Circuit of the LUX A501.

6-channel amplifier for the sub speaker. But using the power op amp, the sound quality far exceeding expectations was obtained. The circuit. In addition, in order to reinforce the bass of a sealed sub​speaker was manufactured low boost amplifier. The circuit.

Speaker System

As for the speaker history there is a variety. Speaker system 1, coral beta-10, Onkyo HM500MK2 and dual Matsushita 5HH17G.

It is 4.7m of back load length, but cannot revitalize a low level in comparison with the size of the box at all (Because an opening is small) resonance is big and because the tweeter is arranged into left and right、if interference occurrence (you try thinking prosperously in left and right direction, natural). It became same retirement, there is no either storage space and became incineration. The gallant figure which is not now when the net is removed. And, the internal constitution. Appearance was involved , the red carpet is placed on top. (However, I have a very good memory for sound of a piano and a drums)

Speaker system 2, now in the box of the same 500 liters was formed with the Pioneer PWA38 and the Onkyo HM500MK2 and the Matsushita 5HH17G. When However, compares with the squawker of sound other things, did not escape part insufficiency excessively. (The tweeter is low efficiency, low resolving power. And, What was fatal A high-pitched tone happened by division vibration, and the woofer was to have been the sound that I did not bear if I heard it. However, most Speaker not a little has this tendency) however, asfor the middle limits it was delicate sound from presently, you have remembered.  frequency response which was measured with the 1m on the axis.

Speaker system 3, it becomes the present front speaker. The JBL 2215B, LE85 + horn the coral (threw away the shortcut horn and the acoustic lens of LE85 attachment, (The sale of this combination, I think I have great doubt)), with foster T925(T925A was not installed to a baffle board). 400Hz, the 6kHz cross. frequency response (old bass reflex) which was measured with the 1m on the axis.

Recently, the urethane edge of the woofer rotted, being to start falling, repapered. (As much as 2 days depended on exchange) furthermore unhappiness to continue, the LE85 press of the diaphragm being not tight that tilted and became the way which the voice coil rubs.

You cannot correct only this.... Some days ago, it meaning that medieval times enter into the hand, when you exchange, improvement of the normal position. sound quality which becomes substantial was assured. The place was disconnected, after that 1 year, the woofer which exchanges the with special care edge.

(As for cause corrosion of voice coil). However, being fortunately, to be able to procure the changing cone of the JBL 2215A, it exchanged and it was possible to make revive. The cone to become original color, also sound, from the sound which dries, to return to the sound which has the moisture, because it could experience original sound, the happiness the in unhappiness? But the happiness did not continue, and an urethane edge rotted again and changed it. (At last the urethane gives up; and to an edge made by a nonwoven fabric)  The left frequency response, right frequency response (The edge material changed and some resonance increases occurred). Recently, creating a channel divider 24dB/oct, I was changed to three multi-channel system. In addition, because the bandwidth of JBL 2215B is about 400Hz, the high cut-off frequency has to 560Hz instead of 370Hz. Latest left frequency response, right frequency response.

explain this speaker theoretically. Attaching the foot, it raised, escaped from the baffle effect. At the beginning, to a bass reflex, irregularity of the Doppler effect with the curvature of the Vinyl disk was prevented, because CD is unlike LP the warp of the board, it designated to close (So that low level was natural, and the resolving power was high, and it was improved large sound quality). However, because also the expensive speaker prevents resonance, it wants heavily and making use of the strong box while (you cannot avoid sound quality deterioration) as for having made bass reflex it is doubt truly. The woofer installed by way of the sub baffle, prevented resonance. You removed unit from the center, avoided corner interference. In order to put out the 30Hz with the 38cm, it made the 500 liters. In addition, the tweeter of a JBL system has muddiness of sound, and since the physical characteristic is not good, either, it has not been adopted.

However, the outline of a square close to the internal standing wave is not taken into account in theory is not good. (Non-prime Relations) In addition, room resonance disturbance of 80 Hz and 200 Hz is difficult to suppress. By the way, it is truly regrettable to be the tendency which recently does not place the frequency response and so on, physical quality of the speaker even in the specialized magazine.

 Speaker system 4, the going down of the front speaker of former times the rear speaker it installed the machine. Pioneer PWA38, Onkyo HM500MK2 With Matsushita 5HH10 650Hz and 6. 5kHz crosses. The frequency response.  which was measured with the 1m on the axis special. Because other than sound, the HIFI it is inexpressible even in compliment, in regard to this you do not feature. In addition, this speaker is now retired.

 Speaker system 5, as for the machine being the old sub speaker (Ceiling speaker) for surround verification, in order all to make channel identical those which it produces in height. The low range does not have the solution. As for the frequency characteristic of the upper range, a ratio is obedient, but the cloudiness of the sound by the division vibration is not avoided because it is corn. The frequency response. 

 Speaker system 6, as for the machine being the new sub speaker for surround verification, in order all to make channel identical those which it produces in height. Manufactured in a sealed, low-frequency correction at low boost. The frequency response is relatively flat. The sound quality is straightforward. Alright well super bass, the subwoofer does not feel the need at all. However, the resolution is not very high, do not put out loud. circuit. (Measured at 1m on axis), the frequency characteristics of the naked, the frequency characteristics of the post-low boost. By opening legs, will be able to prevent tipping (somewhat).

Because the horn speaker resonates, the thing to put in case without fail. It hang or without locking it, it is out of the question.

Actually, Speaker system 0, Matsushita compound 2WAY unit was used you removed from the machine and the back load, Coral beta-10 was used in bass reflex. Speaker system 1.5, it had the machine, but also the sound quality badly being either the data not to remain, you exclude.

Headphone

Stax condenser type SR-X + SRD-7 (never, it picked up with the bulky refuse with). The sound quality is another dimension. Sennheiser HD-414 (the sponge rotting immediately)

 

Being also music appreciation and book-reading to be hobby.

Library

Main in the book library is SF.

Main in the record library is VINYL disk.

Main in the game library is DOOM.

Something more

I can curve being defeated story, but 4004. Larger one 2k bit EPROM. It meaning that logical operation is weak, it is said it is not the worldwide first microcomputer in true sense, but concept just the microcomputer. It probably is one of large invention of 20 centuries.