Power Amplifier - 20Wrms/channel : DR20W by 1diy

[n0th1n6]

@Dandy, sir click mo po yung logo ng YouTube para ma view mo from youtube website.

@Jayke, midrange yung ginamit ko na speaker. HFW-50 pero di ko makita part number na yan sa Dai-ichi site. 72Hz Fs nyan, 50W nakasulat sa magnet, 8ohms. 82dB sensitivity, ayun na yan sa measurements ko gamit WT3.

BTW ito na pala nung natapos. Pinalitan ko ng heatsink kasi gusto ko gamitin sa 4ohms



Ang kahon


Test fit




Abangan ang susunod na kabanata pag natapos na pati speaker

[pEN DoTA]

Hello to all Audio Hobbyist, diyer’s and Music Lovers,  heto  share ko ang  IC  Power Amplifier base sa NS LM1876F,  capable of delivering 20Wrms/channel,  40Wrms Stereo,  good enough for home use (room use)  to deliver that kind of hifi music you always wanted to hear.

We, at 1diyTEAM called it DR20W,  it is primary  designed to Interface with the Digital Audio Tone Control (DATC)   http://www.electronicslab.ph/forum/index.php?topic=3775.0      that can be controlled to Automatically Turn On/Off at any time - 24 hours.   But of course,  the DR20W can be use to interface with other Tone Control / audio gadgets.

With DR20W  +  DATC   +  do diy MP3 Player  +  good pairs of Speakers, will make a complete a  diy  personal Home sound  systems.    { Do diy MP3 Player  :   http://www.electronicslab.ph/forum/index.php?topic=26831.0   }     The DATC is  a modern digital tone control with  surround processing, matrix and simulated surround that can be reproduced in the same front speakers – this makes the listening pleasure better than other  tone control.

The 1diyTEAM choose the IC amplifier other than its discrete design,   simplifying design, rugged, compact and reduced pcb size.  In the same manner, we also interested with latest  technology of digital power amplifier -specific to Class-T by tripath.

For  technical know how, the LM1876F datasheet described most of the information,  check this link to download the datasheet    http://www.alldatasheet.com/datasheet-pdf/pdf/224982/NSC/LM1876.html   
Though, it appears to be Integrated and looks simple to design or  make,  indeed,  but then, there are issues that need to solved, like noise, oscillation, heating,  crosstalk, etc.. etc.. that appears when integrating into a system with other audio device / gadget – this makes the challenge to the diyers.


Here,  download the
a)   Technical preliminary information  :     http://www.1diycentre.com/DR20W_diiyPowerAmp_R1.0.pdf
b)   Schematic / Block Diagram  :    http://www.1diycentre.com/RD20W_hifi_schematic_diagram.pdf

Here are some pictures :
Prototype :

Prototype on the Universal PCB

First PCB :



Testing :


On its plastic case :


I believe that,  this design is not optimum and still many room for improvement, play around with it and learn from it.   I hope to hear from you, and I would be glad to hear anything you can come up with in using our DR20W.

Sa Audio Hobby,  I have completed the  a systems  with the integration of modular board :
1.  DR20W Power Amplifier   +   Digital Tone Control   +  MP3 Player
2.  5.1 DTS / Dolby Digital AC-3   diy  Home Theater

wow! ganda! +1 for u master.

[1diyMARKET]

There is a video link on your post,  kaso di ko makita/ mabuksan ang video.

hehehe,  naka block ang video,  ibig sabihin, nadiyan ka pa din sa bansa 'niya', kala ko na sa city of Pines ka na.

@noth1n6,  special request to send to my emails iyong mga picture para ma-update  ang website,  http://www.1diycentre.com/DIYers_Space_files/Page494.htm  nitong project na ito.  Permission to post there iyong mga screen shots mo,  ok lang ba sir?   Salamat po.!

[pEN DoTA]

@n0th1n6
1 point for u sis

[Dandy]

nice project there nothin1n6,  for sure, I am anxiously waiting for the next chapter.

This Power Amplifier  DR20W  (40Wrms stereo)  is also candidate for the DR100W_Concept -----  Power Amplifier Module  (http://www.electronicslab.ph/forum/index.php?topic=27749.40)   ,  hindi pa lang nasusubukan ang Integration,  kailangan din ang Software modifcations sa Standby at sa Mute,  kasi magkaiba ang logic level nila sa TDA8923 (ST).

[n0th1n6]

@noth1n6,  special request to send to my emails iyong mga picture para ma-update  ang website,  http://www.1diycentre.com/DIYers_Space_files/Page494.htm  nitong project na ito.  Permission to post there iyong mga screen shots mo,  ok lang ba sir?   Salamat po.!

No problem sir. Ill take a much better picture tomorrow then send you the album in picasa. I will be drilling panel holes tomorrow. Sana wag sumablay lalo na sa RCA jack kasi sayang yung face plate ng enclosure. Meron pa palang kulang ito, bibili pa ako ng 22 - 0 - 22 5A na transformer o baka pagawa ako kay sir tony para tama rating ng trafo.

[nucleus]

No problem sir. Ill take a much better picture tomorrow then send you the album in picasa. I will be drilling panel holes tomorrow. Sana wag sumablay lalo na sa RCA jack kasi sayang yung face plate ng enclosure. Meron pa palang kulang ito, bibili pa ako ng 22 - 0 - 22 5A na transformer o baka pagawa ako kay sir tony para tama rating ng trafo.

maganda iyan sir, kung idrill ng hindi pa inaalis yung protective sticker

[n0th1n6]

^ Yes sir. Ganun nga ang gagawin ko, ang problema ko lang ay yung accuracy ng butas. Gusto ko kasi maging malinis yung pagkakabutas para sakto lahat pati ang butas ng turnilyo. Mas maganda tingnan kung parang commercial product ang kalalabasan ng panel

[Dandy]

^ Yes sir. Ganun nga ang gagawin ko, ang problema ko lang ay yung accuracy ng butas. Gusto ko kasi maging malinis yung pagkakabutas para sakto lahat pati ang butas ng turnilyo. Mas maganda tingnan kung parang commercial product ang kalalabasan ng panel

just try it Sir,   kung mayroon sana tayo CNC eh....maganda sana, close to commercial na.   

The picture in the first page,  I am one of the "taga butas"  while drinking red wine...   it is not perfect,  it is trial and error.   

For those with the DR20W,  it should be nice to add extra  space for some stuff like the preset Equalizer, the Protection Module,  I also able to get the DR20W working on the SMPS.  The Equalizer is really good as an ADD-on value to any power power Amplifier which deliver quality music to our listening pleasure.    The power Amplifier, DR20W  or any other amplifier is a flat response and do not provide equalization or Tone control.

{but in reality, not all power amplifier sounds as flat as we think,  some amplifier really sounds better than the other, the DR20W is not a superb one, its just nice to have one, and there are rooms for design improvement}

[Dandy]

Here is an update of DR20W  using SMPS :



I used 2 pcs +24Vdc @ 3 Amp.

A gadget is also included in the test ---called Protection Module which is used to protect the speaker from Overload. If the dc offset voltage (dc output) is greater than  "preset"  positive or negative voltage, the speaker will be disconnected from the Power Amplifier (by relay action),  I am working on a circuit on how to detect the Clipping Level, but it looks difficult,   kung may alam kayong circuit, share niyo naman (the clipping threshold I want to detect is the equivalent of 10% distortion at 1KHz).

[Dandy]

and............ finally,  after the SMPS test ,  the DR20W Power Amplifier is used as PA Module  in the "conCEPT":



In this setup,  the DR20W Power Amplifier is being controlled by a MCU, its MUTE and STANDBY is being commanded by MCU from the Control Module.  If the system  goes into the Standby Mode,  the DR20W will go into sleep mode. 

To avoid noise or that kind of unwanted noise that can be heard from the speaker during the power On / off,  the DR20W MUTE is being controlled in a way to avoid those noise.

[thoniodee13]

mga sir patulong naman po sa hdt 1000pro na amplifier ko. may nasususnog po kcng 100ohms na resistor sa left chanel circuit nya.. check ko a transistor ok nman,

naninira pa pla 2n5551 pagitan ng output transistor.

ung disign po ng circuit parang konzert 502 na fake.
apat ung transis na nasa heatsink c5198 at a1941.output . d669 at b649 ung driver.

ano po kaya dapat i check dito??

advance salamat!!

[j a y k e z]

^ sir gawa ka na lang ng bagong thread regarding sa issue mo dito --> http://www.electronicslab.ph/forum/index.php?board=116.0

sure madaming master na tutulong sayo dun 

[n0th1n6]

just try it Sir,   kung mayroon sana tayo CNC eh....maganda sana, close to commercial na.   

The picture in the first page,  I am one of the "taga butas"  while drinking red wine...   it is not perfect,  it is trial and error.   

For those with the DR20W,  it should be nice to add extra  space for some stuff like the preset Equalizer, the Protection Module,  I also able to get the DR20W working on the SMPS.  The Equalizer is really good as an ADD-on value to any power power Amplifier which deliver quality music to our listening pleasure.    The power Amplifier, DR20W  or any other amplifier is a flat response and do not provide equalization or Tone control.

{but in reality, not all power amplifier sounds as flat as we think,  some amplifier really sounds better than the other, the DR20W is not a superb one, its just nice to have one, and there are rooms for design improvement}

Baka bukas matapos ko yung case. Nothing special sa case, para lang hindi na nakakalat sa mesa ko pag ginagamit. Acrylic yung ginamit ko pero dahil wala akong belt sander baka di rin maganda ang mga joint hehehe.

Lalagyan ko to ng tone control na base sa sample ng TI. Para me konting adjustment man lang.

[n0th1n6]

The acrylic case. Post ko mamayang gabi yung latest pic. Ito nung ginagawa ko pa lang

Notice yung sa pinagdikitan, hindi ata maganda yung pandikit ko kaya ayan parang me usok. Naghahanap ako ng pandikit an locktite ang brand, malinis kasi ang dikit nun.

[Ikasamoko]

pangit talaga yung glue dyan...need mo chloroform which is too hard to obtain..

[n0th1n6]

Sir tip naman kung san ako makakabili nyan. Tnx

[profpat]

you may use lacquer thinner or pvc glue as bonding chemical for plexiglass !

[n0th1n6]

you may use lacquer thinner or pvc glue as bonding chemical for plexiglass !

Yan ang hindi ko alam yung PVC cement although marami ako nyan. Masubukan nga. Pogi point sayo sir...

[profpat]

yung iba gamit ay clear silicone sealant for glass bonding, i guess pwede try sa plexiglass, not sure kung mag bond na maigi!