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I would like to express concerning one audio of hobby

Configuration (Placement, front, left)

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

Arm : Audio Technica 1005MK2 (Airlift 6005 it is attached)

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

SACD/DVD player : MARANTZ DV-8300, DENON DBP-1611UD､OPPO BDP-93

Open Reel Recorder : Sony TC-6950

Cassette Recorder : Matsushita RS-275CU, AKAI GX-73

FM/AM tuner : Matsushita ST-3600

HDMI decoder : Onkyo SA-205HDX (Modify 1, Modify 2)

PC audio interface: Aim AS372 (for USB), ASUS XONAR D2 (for PCI)

Surround decoder : Handmade QS/SQ logic decoder, Involve Surround Master V1/V2, Sansui QSD-1 (Evaluation only), Sansui QSD-1000 (Evaluation only), Sony SQＡ-2030 (Modify) (Evaluation only)

Pre amplifier : Handmade (Kaneda Early Type)

Main Speaker System Channel divider : Handmade (3way 24dB/oct)

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

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

Sub Speaker System Main amplifier : Handmade (90W), Onkyo A907X

Sub Speaker System : ParcAudio DCU-171PP (- 650Hz), Onkyo HM500A-MK2 (650Hz - 8KHz), Matsushita 5HH10 (8KHz -)

3D Speaker System Channel divider : Handmade (2way 18dB/oct)

3D Speaker System : Foster FW-208N (- 100Hz), ParcAudio DCU-F081PP (100Hz - 5KHz), Foster FT96H (5KHz -)

Surround Speaker System Main amplifier : Handmade ( 6 channel 80W )

Surround Speaker System Sub Main amplifier : Handmade ( 6 channel 38W )

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

Headphone : Sennheiser HD-414

Display : Matsushita TH-L17C10

HD Recoder : Matsushita DMR-XW30, Matsushita DMR-BR550, Matsushita DMR-XP11, Matsushita BW-695

Source

The motor is Synchronous rim drive type (Unlike the belt-type or a servo motor type, it is merit that it is not broken in semi-permanent). The arm is Technica 1005II (slide ring type, once you use it, you can't use anything else). And the arm lift is Airlift 6005 (can be operated with the lid closed and there is no need to worry about oil leakage). SACD is a Marantz DV-8300, but because of increased reading errors, it moved to DENON DPB-1611UD, but since the occurrence of mute has recently become prominent, it is preparing to move to OPPO BDP-93.

At a later date, OPPO BDP-93 also developed similar symptoms, and it was found that DENON DPB-1611UD was not out of order. After investigating the cause of the mute, it is a symptom that occurs in the HDMI authentication operation (occasionally performed), and it is said that this is an HDMI specification and cannot be fixed. Since there is no way to do it, the occurrence is prevented by disconnecting the HDMI cable to the TV during playback.

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, (Initial single-ended type) Kaneda Type. The inside and circuit. I've been using it for about 50 years, but recently I gave up my seat to the next successor. The Kaneda type, which appeals for circuit simplification, had problems such as disturbance / component sensitivity, FET voltage, and TR withstand voltage. However, it was epoch-making because anyone could easily make a (super) high-performance machine. (If not particular about using original parts)

Furthermore, I tried to remake the successor to the above Kaneda Type preamplifier with a printed circuit board this time. Appearance , backside ,inside and circuit. Initially, the EI type was used for the power transformer. However, there is a leakage flux, and in order to secure the S/N, the mounting position and the angle are severe, so I ended up using a cut core.

Channel divider etc.

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

Channel divider (for 2-way 3D system). The inside and circuit. Also put low boost function.

Bass distributor (for surround system). The inside and circuit.

Low boost amplifier (for sealed subspeaker). The inside and circuit.

Channel divider (for 4-way multi-system). The inside and circuit. Also put low boost function.

Main amplifier

At first, I made an integrated amplifier when I was in junior high school, but I broke the power TR during the adjustment and the huge hiss noise of the pre, and it failed. Therefore, I could not endure the fragile transistor, and I made 6BQ5 single etc. next, but I was disappointed by the so-called vacuum tube sound (which is a low tone without tightening) and immediately discarded it. Next, I was induced by the vivid sound of Kaneda amplifier I heard at an acquaintance's house, and I made my own DC power amplifier and used it for a while.

For the main speaker, initially tried several tube amplifier and DC amplifier. However, since the speaker does not have the merit of handmade, the main system consists of Kinsui A 501 kit, finished product and junk repair item. It was disappointing because the A501 (solder confirmed) finished product had the same price as the kit.

Although not described in detail, since the shield is weak and ham enters in A 501, it is necessary to drop the punch metal part to earth. Also, the input VR is also as high as 100kΩ, so hum is entered, so change to 20kΩ. Circuit of the LUX A501.

6-channel Main amplifier for the sub speaker. But using the power op amp, the sound quality far exceeding expectations was obtained. The inside1 and inside2. The circuit.

Main amplifier for the sub speaker, is an internal. Circuit of this time, I was designed with discrete components. Felt a margin of power, better or bad, got the sound quality I expected. The circuit.

6-channel Main amplifier for the sub speaker, is Rear,is an internal. This time designed it with IC, but can not deny the lack of some margin. Better or bad, got the sound quality I expected. The circuit.

Main amplifier for the sub speaker. But using the power op amp, the sound quality far exceeding expectations was obtained. The inside The circuit. The reason why good result was obtained is that the drift of the DC offset which is the cause of the sound quality deterioration due to the operational amplifier is small and the DC servo which is the cause of sound quality deterioration is unnecessary probably.

6-channel Main amplifier for the sub speaker. Also designed by the IC again this time, but do not deny some margin shortage, the sound quality far exceeding expectations was obtained. The inside. The circuit.

Main amplifier for sub-speaker, internal. For this time, I made the printed circuit board raised in a discrete configuration with reference to the power op amp circuit. The sound quality as expected was obtained. That is the circuit. Designed with top priority not being affected by disturbance.

This is the latest version of the main amplifier for the sub-speaker, which is the internal, latest circuit. Again, this was designed with the highest priority not being affected by disturbances, so the operation was stable and it worked, and clearer sound quality was obtained. (The DC offset is about 1mV and the DC servo circuit is omitted.)

4-channel main amplifier for sub speaker, inside. This time again, it was designed with IC (LM1875) again, but some power shortage cannot be denied, but the sound quality as expected was obtained, good or bad. The circuit. In addition, this IC generates a large amount of heat in spite of its small size. (It required trial and error for the heat sink and the mounting method)

4-channel main amplifier for sub speaker, inside1, inside2. The circuit. This time, it was designed with discrete parts, and the expected sound quality was obtained.

I tried making a discrete op-amp.

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. (I remember, It was a sound quality there is no salvation like, but only the drums and piano and was the sound of a powerful fairly) The panel is full range, 2-way, 3-way switching, ATT (trans tap type), and phase switching.

Speaker system 2, was configured with Matsushita 5HH17G and Onkyo HM500 and Pioneer PWA38. Box is 500 liters that is currently in use. Other, was too underpowered when compared to squawker of Onkyo. Resolution and efficiency of the tweeter is low. The division of vibration woofer, the sound of the mid-high range is emphasized in particular, it did not bear to listen. However, SP most of this trend is not a little. However, I remember the sound of the mid-range was a delicate sound than those of today. circuit. It is the frequency response on the axis 50cm. As you know, 5HH17 is called a horn, but the structure is a direct radiator (dome), so of course the tweeter is not the sound of a horn.

Speaker system 3, it becomes the present front speaker. It's a size and a board-cutting. The JBL 2215B, LE85 + horn is Coral AH500 (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 50 cm on the axis.

After a while, 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.... Somehow, 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. Recently, creating a channel divider 24dB/oct, I was changed to three multi-channel system. Because the bandwidth of the 2215A is about 400Hz, the cut-off frequency of woofer side is 560Hz instead of 370Hz. As much as possible, missing middle reblogged so as not to occur. Latest, left frequency response, right frequency response.

I 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 (Still not enough). 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. 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. From frequency response, 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 cone. (unit is Foster FE83)

　Speaker system 6, as for the machine being the 17 liters sealed type new sub speaker for surround verification, in order all to make channel identical those which it produces in height. Using WAVECOR WF118WA01 (- 2KHz), DAYTON ND20FB-4 (2KHz -). It's a size,board-cutting. From frequency characteristics of the naked(upper fig)/the post-low boost(Lower fig), low-frequency correction at low boost. So that frequency response is relatively flat. The sound quality is straightforward. Alright well super bass, the subwoofer does not feel the need at all. However, because it is a direct radiator, even if the Frequency characteristics are flat, it cannot escape from the natural vibration, so the sound is not real, and because of its small diameter, a large volume cannot be produced. circuit. Will be able to prevent tipping (somewhat). Incidentally, it is a frequency characteristic measured with an omni microphone from a distance of 50 cm.

　Speaker system 7, new sub speaker (and set saran net). Manufactured in a the 38 liters sealed, but be possible to cope with the bass reflex type. Using ParcAudio DCU-171PP (- 650Hz), Onkyo HM500A-MK2 (650Hz - 8KHz), Matsushita 5HH10 (8KHz -). It is a size,board-cutting. From the frequency characteristics, super bass can not be played, but the sound quality is real and delicate. circuit. For reference, the frequency characteristics at the time of the sealed type (blue), bass reflex type (black), sealed + low boost (red).

　Speaker system 8, new 3D sub speaker. Using WAVECOR SW215WA01 (-100Hz), ParcAudio DCU-F081PP (100Hz-5KHz), Fostex FT96H (5KHz-), 25 / 44 liters bass and the 8.5 liters treble. It is a board-cutting (can change the volume). Bass-Reflex also sealed it is also available. circuit. For reference, the frequency characteristics at the time of the sealed type (blue), bass reflex type (black), sealed + low boost (red). Usually, listen in a bass reflex type. (It is the final frequency characteristic) Currently, DCU-F081PP is exchanged for TangBand W3-881SJF. How to install the bass part.

　Speaker system 9, new Bass-Reflex sub speaker. Using SB Acoustics SB13PFC-4(-300Hz), ParcAudio DCU-F081PP(300Hz-5KHz), Dyton AMT mini-8(5KHz-), 22 liters. It is a size,board-cutting (Include spare baffle). available. circuit. For reference, the frequency characteristics, Currently, DCU-F081PP is exchanged for TangBand W3-881SJF. the frequency characteristics.

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 EAS-20PX27 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

Sennheiser HD-414 (the sponge rots easily, which is a drawback). However, I almost never use headphones or earphones. This is partly because they are very inconvenient and make listening very tiring, but the main reason is that the contents of the recording are often not recognizable by ear alone. (As you know, there are ultra-low and ultra-high tones that cannot be heard by the ear. And also the resonance of the sound and the position of the instruments. Furthermore, surround sound sources are completely useless.)

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

Story will turn, but it is chip of 4004 BUSICOM Japanese company has invented. Larger one 2k bit EPROM. Function of logic operation of 4004 is weak. Therefore, it is said that it is not in the world's first microcomputer strictly. However, the concept is unmistakably microcomputer. This is one of the great inventions of Japan in the 20th century that has not been written in the history of technology.