Rebuilding a 5.1ch home theater system on a low budget (DENON/ONKYO)

Last updated: December 18, 2023 at 3:21 PM

DENON's now obsolete home theater system DHT-300-S (released in March 2002) was used for a month to broadcast 5.1ch satellite broadcasts (audio codec:MPEG2-AAC 5.1ch) has been rebuilt into a home theater system that can be viewed.

We installed it in the living room (7 tatami mats) of the apartment, but because the room is too small and the budget is limited, we have put together a high-performance, compact AV amplifier and speakers as much as possible.

I bought it from Mercari or Yahoo auc to keep it on a low budget, but especially for the speakers, would it be better to buy second-hand and good-quality high-quality speakers than to buy new and cheap ones? think.

The configuration of the replaced device is as follows.

■ Cable: Amazon Basic 14 Gauge Speaker Wire [99.9% acid-free copper]
■ AV amplifier: DENON AVC-M380 (5.1ch home theater system DHT-M380 set)
■ Super woofer: DENON DSW-M380 (5.1ch home theater system DHT-M380 set)
■ Center speaker: ONKYO D-108C(D)
■ Front Speaker: DENON SC-M40-CW
■ Surround speakers: DENON SC-A33-BH

The AV amplifier (DENON AVC-M380) installed this time is the specification of one generation ago.
The av amplifier is connected to the TV and blu-ray disc recorder via an optical digital audio cable.
If you're on a budget, you can connect your TV with an HDMI cable. ARC The latest AV amplifier compatible with the 3rd generation optical disc standard that can be connected to the (Audio Return Channel) terminal (Bluetooth receiver,maximum 7.1ch surround、Dolby TrueHD、DTS-HD Master Audio、Dolby Atmos, Support for other codecs).

The details of each AV device currently installed in my home are explained below.

≪ Cable Amazon Basic 14 gauge (OFC) ≫

Because the current cable is thin and poor, I replaced it with a thick cable of the following 14 gauge from Amazon to improve the sound quality. However, in fact, because it was too thick to handle, if there was no concern with the sound, it might have been good even with 16 gauges. However, 2,404 yen at 30m made by OFC, I think that it is a bargain.

OFC (oxygen-free copper) is an active removal of oxygen among impurities contained in TPC (tough pitch copper). OFC is represented by 4N OFC, with a purity of 99.99% of copper. Every single digit of purity increases the number of N, and it becomes more expensive. There are also 6N, 7N, and up to 8N copper wires, and this OFC system is now the mainstream of speaker cables.

By the way, the smaller the gauge number, the thicker the wire. In 14 gauges, 1.6mm x 2 wires are included in the cable.
Generally, it is said that the thicker the wire, the lower the electrical resistance and the lower the signal loss, which improves the sound quality of the audio.However, if the wire is too thick, the electrical signal in the high-frequency range is attenuated. It doesn't seem that thicker is better.
Also, if the cable is too thick, it may not be able to enter the terminals of the amplifier or speaker, so I think it is better to select the cable after confirming the terminal specifications first.

■Basic 14 Gauge Speaker Wire [99.9% Oxygen Free Copper] 100 Feet (30m): Amazon.ca: Electronics Price: 2,404 yen (free shipping)

● 14 gauge speaker wire (30m) for AV amplifier connection
● Made of 99.9% oxygen-free copper (OFC), enabling high-quality signal input and output between audio devices.
● The poles are color-coded in two colors, red and black.

≪ Amplifier DENON AVC-M380 ≫

DENON 5.1ch home theater system DHT-M380 AV amplifier (AVC-M380).
After completing the initial settings of the amplifier, you can enjoy 5.1ch sound immediately. As it is very compact, we are not troubled with setting.
Although the level adjustment (± 12dB) of each channel (speaker) is possible, there is dissatisfaction that the parameter of the preset equalizer cannot be changed, but it is an AV amplifier with sufficient quality and power despite the small housing.
However, due to its compact size, the amp becomes very hot when used for a long period of time, so there is concern about thermal runaway. I haven't confirmed it yet with this machine, but Kakaku.com has reported "explosive noise failure", so I'm planning to observe the progress in the future.

As for the DHT-M380 home theater set, the AV amplifier and super woofer are fully usable, but the center speaker and satellite speakers (full range speakers) cannot remove the saran net, and the sound range (120-20KHz) is narrow. Not suitable for listening to music.
Therefore, I left only the DHT-M380 super woofer and replaced all the other speakers with different ones. The impedance of the speakers is all unified to 6Ω.
The mainstream of AV amplifiers currently on sale seems to be 8 Ω, so if you plan to introduce the latest AV amplifier, it is better to unify to 8 Ω speakers that require less power consumption .

Release Date: Early August 2007
Sales price: around 40,000 yen
Purchase price: 9,000 in MercariCirclePurchase DHT-M380 (made in 2009) as a set (shipping included)
Website:DENON DHT-M380 / DHT-M380 Instruction Manual

● Practical maximum output / Front: 20W + 20W (load 6Ω, JEITA), Center: 20W (load 6Ω, JEITA), Surround: 20W + 20W (load 6Ω, JEITA), Subwoofer: 20W (load 6Ω, JEITA)
● Output terminal / 6Ω to 16Ω
● Input terminal / optical digital audio input terminal x 3 / analog audio input / output terminal x 4
● Frequency response / 10Hz-50kHz: +1.5, -3dB (in analog input direct mode, total)
● Power consumption / 70W (standby power: less than 1W)
● Maximum external dimensions / W210 × H70 × D325mm (including foot, knob, terminal)
● Mass / 3.9 kg

■ Main features
● Easy connection and easy operation for beginners. Space-saving compact design
● Total output 120W. Equipped with 6ch analog power amplifier
● Essential for DVD software playback DTS AndDolby DigitalAnd 96kHz / 24bit high-quality multi-channel format DTS 96/24 And 2ch stereo sound source can be enjoyed in 5.1chDolby Pro Logic II, And even enjoy the sound of BS digital broadcasts AAC Also supports.5ch stereoDENON-original surround modes such as Hall and Hall are also included.
● High-quality aluminum front panel design that follows the design of the DENON New AV amplifier

≪ Super Woofer DENON DSW-M380 ≫

This is a super woofer (DSW-M380) attached to DENON's 5.1ch home theater system DHT-M380.
Because it is installed vertically, it does not get in the way in the installation and produces ample bass.

The layout of the home theater system this time was that the front speakers L were placed on the left edge of the TV and the front speakers R were placed on a rack placed on the right side of the TV, so the center speaker was placed right next to the TV in the center. Was.
This super-woer (DSW-M380) is also installed in this position, so the center speaker is placed vertically in the toll boy speaker style with a videotape and insulator on top of it. In addition, even if it is said that the insulator, the material is a foundation puff bought in daiso, but w

■DENON DSW-M380 (5.1ch home theater system DHT-M380 set)

● Model / 1 way / 1 speaker, bass reflex type, magnetic shield design
● Reproduction frequency band / 30Hz to 240Hz
● Maximum allowable input / 60W (JEITA), 120W (PEAK)
● Input impedance / 6Ω
● Speaker unit / 16cm cone type x 1
● Output average sound pressure level /? DB (W / m)
● Dimensions: W135 × H420 × D304mm (without pedestal), W180 × H432 × D304mm (with pedestal)
● Quality ／ 5.5kg

■ Main features
● Reproduce powerful bass with slim body
● A 16cm driver is used for a slim design wooden cabinet that expands the freedom of installation
High performance subwoofer

≪ Front speaker DENON SC-M40-CW ≫

DENON's bass-reflex 2-way, 2-speaker bookshelf speaker. Because it is deep, it produces good bass even though it is small.
It features the round and rich sound quality typical of DENON. Kakaku.com's evaluation seems to be quite high, but compared to the sound of the BOSE 111AD speaker, which has been installed separately for karaoke, it lacks clarity, and it feels like the midrange is canceled out by the bass. increase.
If you have a budget, I think you can choose other bookshelf speakers such as DALI, but they produce good sound for the price, so it's not bad in terms of cost performance.

Since this system already has a super woofer, we inserted a sound-absorbing sponge into the bass reflex duct of this unit in order to balance the bass. However, if you cram it too far, the sound will become a little muffled, so I think it is necessary to make an appropriate adjustment. Also, by adjusting the amplifier level, the subwoofer channel is set to -2dB to suppress bass.

■ DENON SC-M40-CW [Cherry pair]
Release date: Early June 2015
Price: 17,800 yen (pair, excluding tax)
Purchase price: Buy at Yahoo Auction at 7,630 yen (including postage)
Website:DENON SC-M40

● Model / 2 way / 2 speaker bass reflex type
● Reproduction frequency band / 45Hz-40kHz
● Input impedance / 6Ω
● Maximum allowable input / 60W (JEITA), 120W (PEAK)
● Speaker unit / woofer: 12cm cone type x 1, tweeter: 2.5cm soft dome type x 1
● Output average sound pressure level / 83dB (W / m)
● Dimensions / W145 × H238 × D234mm
● Quality ／ 3.6kg (1 set)

■ Main features
● 2.5cm soft dome tweeter
A soft dome tweeter that reproduces natural sound is adopted. The air pressure on the back of the diaphragm at the edge that supports the outer periphery of the diaphragm has been optimized to achieve accurate piston motion.
● 12cm paper cone woofer
Equipped with a paper cone woofer with a diameter of 12 cm, which has excellent response with excellent balance between mass and rigidity. Combined with the bass reflex duct provided on the back, bass reproduction that achieves both richness and sharpness is realized.
● High rigidity cabinet
Reinforced side and bottom panels to increase the rigidity of the wooden cabinet. Suppresses unnecessary vibration and suppresses the sound of the box to achieve clear sound
● Large screw speaker terminals
The speaker terminals use a large screw type that can be securely connected. It also supports banana plugs.

≪Surround speaker DENON SC-A33-BH ≫

This is a 2-way, 3-speaker system multi-channel speaker from DENON from a long time ago.
Surround speakers were installed on the wall, so we chose a compact and high-performance model, regardless of the new or old model, regardless of the manufacturer.

This SC-A33 is characterized by its somewhat ungainly appearance, but it is a unique speaker that uses DENON's original P.P.D.D. system.
It is two-way, but because the woofer is built in on the back, it is a spec of two-way, three speakers. It is small, but the treble and the bass come out enough. However, i think that it is good to use it only for the satellite speaker because it seems to be a little insufficient power in the sound quality to use it as a front speaker.
One notable point is the adoption of a gold-plated brass cut-out speaker terminal corresponding to the banana plug, and only the appearance is made without omission w

The average output sound pressure level of this unit is 88dB, and compared to the DENON SC-M40 front speaker, the volume is nearly doubled with a difference of +5dB, so we confirmed the playback level with the test tone of the AVC-M380. and dB adjustment are required. In addition, when this type of speaker is mounted on the wall, the woofer on the back resonates with the wall and increases the volume, so adjusting the amplifier level is essential in this case as well.

In addition to this speaker, ONKYO's satellite speaker "D-108M(D)" was seriously considered, but the size was smaller than I expected, so I decided not to introduce it.

■ DENON SC-A33-BH
Release Date: June 2001
Price: 10,000 yen (1 unit, excluding tax)
Purchase price: Yahoo auction, purchased for 4,600 yen
Website:
　DENON SC-A33 (audio footprint)
　AV Watch – Denon, multi-channel speakers and subwoofer

● Model / 2 way / 3 speaker, bass reflex type, magnetic shield design (EIAJ)
● Reproduction frequency band / 80Hz-90kHz
● Input impedance / 6Ω
● Maximum allowable input / 80W (EIAJ), 160W (PEAK)
● Speaker unit / 8cm cone type woofer × 2 (P.P.D.D. method), direct drive type super tweeter × 1
● Output average sound pressure level / 88dB (W / m)
● Dimensions / W120 × H206 × D148mm
● Quality ／ 1.8kg (1 set)

■ Main features
● Can play up to 90kHz. Equipped with "direct drive" super tweeter for next-generation audio.
● Equipped with a glass fiber cone woofer that uses the P.P.D.D. method
The woofer diaphragm is made of lightweight and highly elastic glass fiber. It reproduces a supple and stretchy midrange and a light and tight low range. Furthermore, this woofer is driven by the P.P.D.D. (Push-Pull Dual Driver) method. By mounting one edge of the front and rear woofers in the opposite direction, the harmonic distortion cancels out, enabling low-distortion, full-bodied bass reproduction.
● Super tweeter with powerful neodymium magnet
● A brass cut-out gold-plated speaker terminal compatible with banana plugs is used. You can enjoy upgrading the sound quality.

≪ Center speaker ONKYO D-108C (D) ≫

ONKYO's bass-reflex 2-way, 3-speaker center speaker.
Actually, I thought that "DENON" would be good for the amplifier and "ONKYO" would be good for the speaker. was solidified with DENON.

DENON's bookshelf speakers have excellent bass, but on the other hand, they tend to sound a little muddy in the midrange. On the other hand, ONKYO's speakers sound clearer and sharper than DENON's. Therefore, in order to supplement the sound quality of the front speakers and add sharpness, we decided to use ONKYO's speaker "D-108C" for the center.

This speaker seems to be highly rated on Kakaku.com, and the mid-tones come out clearly, making it easier to hear vocals in music and dialogue in movies than ever before.

■ ONKYO D-108C(D)
Release Date: May 16, 2008
Price: 12,000 yen (excluding tax)
Purchase price: Yahoo auction, purchase for 3,989 yen
Website:ONKYO D-108C(D)

● Type / 2 way bass reflex type
● Reproduction frequency band / 60Hz-80kHz
● Input impedance / 6Ω
● Maximum allowable input / 80W (JEITA)
● Speaker unit/woofer: 8cm A-OMF monocoque cone x 2, tweeter: 2cm balanced dome x 1
● Output average sound pressure level / 84dB (W / m)
● Dimensions / W275 × H102 × D129mm
● Quality ／ 2.1kg (1 set)

■ Main features
● Center speaker with BASE-V20HD (B) design and tone
● 2cm balanced dome tweeter that achieves smooth playback without disturbance even in the ultra-high range

≪Spare machine≫
Wii U karaoke equipment.
BOSE full-range speaker “111AD”, ONKYO integrated amplifier “A-905TX” and equalizer “EQ-205”, Zoom digital reverb effector “RFX-300”, SHARP subwoofer for Mebius PC.
BOSE 111AD was purchased brand new because I used to run a shop. At that time, I also installed a BOSE 301V, but I sold the 301V after the store closed. The 301V is a 2-way, 3-speaker bookshelf speaker consisting of a high excursion woofer (20 cm), a Stereo Targeting® tweeter (5 cm) in front, and a rear firing tweeter (5 cm). Yes, BOSE's proprietary 301® Direct/Reflecting® speaker system was able to reproduce well-balanced stereo sound over a large area of the store.

The BOSE 111AD was used as a satellite speaker at a store, but it is an excellent speaker that can be used alone.
However, BOSE speakers have a clear and sharp sound from low to high, and they are comfortable to listen to, but they are not pure audio in terms of sound quality, so they are not suitable for applications such as karaoke or background music in shops. I think there are.

■ BOSE 111AD + ONKYO A-905TX + ONKYO EQ-205 + Zoom RFX-300 + SHARP PC-TX-Subwoofer
Although it is analog, it is also connected to the audio output line from the TV, so if you use it together with the AVC-M380, you can also watch in pseudo 7.1ch.

* Reference website
BOSE 111AD： Audio footprint (BOSE 111AD)
BOSE 301Ⅴ： 301® Direct/Reflecting ® speaker system
A-905TX： INTEC 205 A-905TX (S)
EQ-205： INTEC 205 EQ-205 (S)
RFX-300： Zoom RFX-300

≪Installation of insulators≫
Updated September 18, 2018

In the end, in order to further improve the sound quality, we also installed a proper insulator (audio-technica hybrid insulator AT6098, etc.). 😅
Below the center speaker placed on the super woofer, a new brick-like sponge purchased from Daiso (best for real bricks) was installed.