2018/12/29 created
2022/10/24 updated

The TV/display JVC LT-37LH905 has been replaced by SHARP AQUOS 4T-C43AM1. (July, 2019)

Configuration

I repleced TV/display, JVC LT-37LH905, with SHARP AQUOS 4T-C43AM1. The size and resolution has been upgraded from 37" to 43" and from 2k to 4k, repectively.

The TV is fixed on the wall behind Gaudi II, instead of being placed on the TV rack (Hayami J8010). The purpose is that the TV is placed as far from the loudspeakers (SS-309A) as possible.
A reinforcement panel was fixed on the wall, and the mounting bracket of the TV was fixed on the panel. This reinforcement is expected to suppress unwanted vibration of the wall.

For details of the new TV, please refer to the page "Commercial Products".

There are no changes to the other components from the previous revision (Rev.2.02).

Layout

The component layout is as shown on the right (click to zoom up).

The TV is fixed on the wall behind Gaudi II instead of being planced on the TV rack.
The distance between the loudspeakers and the TV has been widened. This contributes to reduce acoustical distortion.

The following two figures show the layout of the whole system.
No change has been made from the previous revision (R2.02).
Since the acoustic design hasn't been made yet, this is a tentative plan.

 

 

 

 

 

 

 

 

 

The panels designated by A, B, and C in the figure are sound absorbing panels. The details are explained in the section "Room Acoustics".

Cabling

The cables used in Gaudi II are as shown in the table below.
There's no change from R2.02.

From	To	Wire	Length	Sender connector	Receiver connector	Note
ADP (SL-1200GR)	MC head amp (HA-213)	Low capacitance unbalanced wire (1-core shielded)	1.5m	RCA plug	RCA plug	SL-1200GR's accessary Tied with earth wire Stereo pair
MC head amp (HA-213)	Preamp (PA-210)	OFC balanced wire (2-core shielded) BELDEN 8412	1.5m	Teflon insulated RCA plug Cold-GND connected	Teflon insulated RCA plug	Unbalanced Stereo pair
DAP (HAP-Z1ES)	Preamp (PA-210)	OFC balanced wire (2-core shielded) BELDEN 8412	1.5m	RCA plug Canare F-10 Cold-GND connected	RCA plug Canare F-10	Unbalanced Stereo pair
BDP (BDP-330)	Preamp (PA-210)	OFC balanced wire (2-core shielded) BELDEN 8412	3m	Teflon insulated RCA plug	Teflon insulated RCA plug Cold-GND connected	Unbalanced Stereo pair
STB	Preamp (PA-210)	OFC balanced wire (2-core shielded) NEGLEX 2549	3m	RCA plug Neutrik NYS373-0	RCA plug Neutrik NYS373-0 Cold-GND connected	Unbalanced Stereo pair
Preamp(PA-210)	Network (CD-211B)	OFC balanced wire (2-core shielded) BELDEN 8412	1m	Teflon insulated RCA plug Cold-GND connected	はんだ付け Cold-GND connected	Unbalanced Stereo pair
Network (CD-211B)	Tweeter amp (MA-208)	OFC balanced wire (2-core shielded) BELDEN 8412	3m	Soldered Cold-GND connected	Teflon insulated RCA plug	Unbalanced Stereo pair
Network (CD-211B)	Squawker amp (MA-215)	OFC balanced wire (2-core shielded) NEGLEX 2549	3m	Soldered	RCA plug Neutrik NYS373-0 Cold-GND connected	Unbalanced Stereo pair
Network (CD-211B)	Woofer Amp (DAD-M100pro)	OFC balanced wire (2-core shielded) NEGLEX 2549	3m	Soldered Cold-GND connected	RCA plug Neutrik NYS373-0	Unbalanced Mono x2
Tweeter amp (MA-208)	Tweeter (T925A)	OFC speaker cable Audio Technica AT365S	2.8m	Soldered	w/o plug Titan oil applied
Squawker amp (MA-215)	Squawker (D1405+H400)	OFC speaker cable Audio Technica AT365S	2.8m	Soldered	w/o plug Titan oil applied
Woofer Amp (DAD-M100pro)	Woofer (FW305)	0.65mm ETP copper single wire 47 Lab Stratos	1.8m (Amp to woofer terminal)	w/o plug Titan oil applied	Soldered	Two wires twisted at 30cm pitch

For some of the unbalanced wires, the shield is connected to the ground at the sender end, and for the others, at the receiver end.
This ununiformity was caused by my changing belief. I used to believe the sheild should be connected to the ground at the sender end. Now I believe the receiver end is better. I'm planning to replace all the line cables after a new preamplifer (PA-218, maybe) is completed.

AC Power Supply

The figure on the right shows the AC power connection (click to zoom up).
It's exatcly the same as the previous revision (R2.02).

The 200V outlet is not used currently.
I probably won't use it in the future too. It's because I am going to use high performance AC/DC conveters for the future amplifiers.
Today's AC/DC converters are so good in regulation. The quality of AC power supply is no longer a big issue. I am gradually losing my interest in AC power supply design.

 

Room Acoustics

I continued to use the acoustic goods I had employed for Gaudi.
For details, please see the page "Problems in Gaudi".

The sound absorbing panels and the acoustic panels designated by A to C in the overall layout diagram shown in the "Layout" section are effective to improve the room acoustics. The effects of other measures are not clear.

Ref.	Material	Size	Location	Effects
A	18mm thick MDF board Sound absorbing panel for ceiling (Solaton Cube 12 SC12-26T)	910 x 1230mm	Leaned against the wall behind the loudspeakers (SS-309A)	Reinforced bass
B	Tokyo Bohon SoundGurard W 50	910 x 600ｍｍ	High position of the left and right walls (2 places)	Somewhat effective in suppressing excessive reverberation
C	Tokyo Bohon SoundGurard W 50	1820 x 910mm	Half wall opposite to the loudspeaker side	Focused sound image Stable localization

I still feel excessive reverberation. Additonal sound absorbing panels are necessary.

The tile carpet I employed in Rev.2.02 was confirmed surely effective.
In addition to that, I found that thick zabuton cushions placed between the loudspeakers and the listening position are also effective. They absorb the primary reflection from the floor. That makes sound images betterl focused.

The reinforcement panel that was fixed on the wall behind the TV/display has reduced the resonance of the wall as I expected.
I'm planning to fix some reinforcement panels and sound absorbing panels on the side walls too.

My Review

The sound quality hasn't been improved so much, but acoustic distortion has been reduced to some extent by placing the TV/display farther from the loudspeakers.
In addition, the zabuton cushion, which is substitues of sound absorbing panels, has improved stereo imaging.

 

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