[lacro]

Put a Panasonic EVJ-Y10F03A54 pot in a box to use as a passive volume control. Sounds good!

[lacro]

hi all, 1st post and I'm really excited about the possibility of these amps. I have a blue YJ on the way as of a week ago. Trying to do lots of learning but electrical stuff is not my strong point. Reading all of this is making my head spin a bit. I'm picking up little bits and pieces. The photos posted help me learn a lot easier.
Anyway, I'm about to buy a few of the pots mentioned here from digikey.  EVJ-Y10F03A54 To build a small boombox powered by the blue YJ and a set of B652's
The rest of the stuff I pick up will probably be from Parts Express as I need to place an order with them anyway. Is there anything else recommended that won't break the bank I should throw in my basket anyway since I'm there?  The only thing I know I need and am having a hard time figuring out still is the PS plug. I plan on burying the brick in the boombox  but want to it to look like the link provided on the outside. The only caveat is that my PS is 3 prong.
http://www.digitaltrends.com/wireless-speaker-reviews/marshall-hanwell-review/#/5
What is the part called that I need to order to screw to the inside/back of my cabinet?


Thanks so much for the help.

Is this the connection your looking for?

https://www.parts-express.com/iec-power-jack-chassis-mount--090-442

[rhing]

I completed a second Yuan Jing 2.0 blue amp build. In this case, I used a Panasonic EVJ 50kohm log taper pot just like lacro's standalone volume control box. These work really well with these Texas Instruments Class D amps and they are very reasonably priced at $1.70 each from Digikey (PN P2G1503-ND).

After receiving the amp module within a week from Yuan Jing, I first removed the stock DC decoupling caps, the input caps and the inductors to begin the upgrade process. Removing the stock inductors and installing the Bourns inductors is not a job for the novice. It was a bit tricky without ripping the surface mount pads from the amp board. I thought I could just heat the solder joints simultaneously with two solder irons and the inductors would fall off. However, the solder that Yuan Jing uses hardly reflows. I had to use a toothpick to apply some gel flux paste to the solder joints and heat the joints with my solder iron while very gently lifting the stock inductors off the board. The space is very tight, so depending on the size of your solder iron, some people may need to temporarily remove adjacent caps to make more room and avoid burning anything. With patience and a gentle tug on the inductors while reflowing the solder joints, I was able to neatly remove them all and keep the surface mount pads in place. After that, I had a lot of cleanup with alcohol and cotton swabs. You can see I couldn't get it spotless, but it was good enough.



Next, I populated the board with the following:

• Panasonic FM electrolytic caps, DC decoupling............Mouser 667-EEU-FM1E152
  ....................................... .....................................Di gikey P12380-ND
• Wima MKP10 film caps, input coupling.......................Mouser 505-M101.0/250/5
• Bourns 10uH inductors, output filter........    ..............Mouser 652-2100HT-100-V-RC
  ....................................... .....................................Di gikey 2100HT-100-V-RC-ND

To mount the inductors, I snipped off the excess lead length and bent the legs to create "feet" to make more contact with the solder pads on the board. I applied generous amounts of solder for good electrical and mechanical connections. With a little work, the inductors fit neatly on the board. I like the fact that the layout has two outside inductors sitting forward from the two inside inductors. This created a bit more room to fit the inductors without having to position them at an angle.



I wired up the amp with some Belden 88641 shielded twisted pair hook-up wire and tied the shields to the source end grounds only (i.e., RCA jack ground tabs). For mounting the board, I used 4-40 Nylon standoffs and screws.




Later, I added a small green LED to indicate when the amp is powered on. I have a 5.1kohm 1/4 watt resistor wired in series with the LED to keep it bright enough to see in daylight, but not too bright during night time listening. I had drilled a pin hole through the face plate to all the green LED to shine through.



I have been burning this amp in using my Alan Parsons Sound Check 2 test CD, which has multiple test tones, frequency tone sweeps and uncompressed music tracks. I try to put as much as 10-20 hours of burn-in time with this CD playing in repeat mode. It really gives the amp a workout, and it seems to shorten the burn-in process.



I've been listening to music off and on since yesterday, and I have to say these mods really add a noticeable level of refinement to the sound quality. The music is more natural-sounding with more detail and transparency. The stock amp is nice, but the mods really revealed how veiled the sound is. The amp sounds smoother, especially with strings, cymbals and vocals.

[lacro]

Whoops, P.S..
Can someone please measure the height of the blue YJ board so I can continue with the box construction?

With the board sitting on the through hole component solder leads, mine is 0.920" sitting on my approx 1/8" stand-offs (recommended) it's 1.050"

[rhing]

With the board sitting on the through hole component solder leads, mine is 0.920" sitting on my approx 1/8" stand-offs (recommended) it's 1.050"

Give yourself some room in case you want to put better power supply caps on the board.

[Poultrygeist]

Am I the only one using a fuse with these boards?

[flavo]

With the board sitting on the through hole component solder leads, mine is 0.920" sitting on my approx 1/8" stand-offs (recommended) it's 1.050"

Thanks guys, I made the enclosure 2"   

Is this the connection your looking for?

https://www.parts-express.com/iec-power-jack-chassis-mount--090-442

thanks so much. Almost exactly. My power cord has a hump in it so won't fit this style. But after searching and finding nothing else I will pick that one up and get a different cord. With any luck I'll find one in my parts here.

[rhing]

Am I the only one using a fuse with these boards?

My fuse is on my power supply: 3A / 250VAC slo-blo.

[matt_garman]

I completed a second Yuan Jing 2.0 blue amp build.
[ ... ]

Nice as always Rhing.  I was showing my wife the pics of your builds, to which she said, "Sorry to say this, but this makes your amp look pretty ghetto."  I can't argue that!

Anyway, just curious what RCA and binding posts you used this time around?

[rhing]

My purpose for posting was to show the modding potential of the Yuan Jing blue amp. The original designer, danzz on diyAudio.com, designed the board for modding. I appreciate any individual effort to create a project using these amps, even if it's a rough looking prototype.

Here's my ugly TDA7297 in an oversized box from Michaels:



Anyway, here are the parts shown in the photo of the rear plate on my latest build:

• Rean (Neutrik) NYS367 RCA Connector, White...........................Mouser 568-NYS367-9
• Rean (Neutrik) NYS367 RCA Connector, Red..............................Mouser 568-NYS367-2
• Keystone 4109 10/32 Binding Posts.................................. ........Mouser 534-4109
  ....................................... ....................................... .............Digikey 4109K-ND
• NKK SPST On/Off Power Switch................................. ..............Digikey 360-3003-ND

I've used more expensive parts like Vampire CM1F-CB RCA connectors and Vampire CMHEX binding posts as well as Pomona Electronics 3770 Gold-plated Copper binding posts. These less costly connectors are perfectly fine, and I probably won't go back to the more expensive boutique parts anytime soon. The NKK power switch isn't cheap, but it's a high quality power switch and perfect for these amps.

[matt_garman]

Here's some pics of my tpa3110.  Not as clean as Rhing's work, but I like looking at other peoples' work, even when it's not particularly neat.  I figure others might enjoy looking at pics too, so here ya go.

I've been using this tpa3110 for quite a while, but with software volume control.  Thanks to this thread I learned about the cheap and cheerful Panasonic EVJ-Y10F03A54 volume pot.  So that was my little project this weekend, to add a volume pot.  I was worried about the soldering job, but it actually wasn't too bad with a helping hands.  At $6, I say the helping hands is a must if you're going to dabble in DIY.

Here's the "guts" of the unit.  The wires I used for the volume control are way too long.  I only get about two hours to work on this stuff while my young kids nap, so for now I'll live with the long wires.  With the Sure tpa3110 being only $10 and the YJ blue tpa3116 being only $20, it's hard resist the urge to keep building more of these, even though I don't need them.









The case is this aluminum case from Parts-Expres (Part # 320-326).  I thought it would be nice to have all the holes pre-drilled.  But, after my tpa3116 build, I realized drilling aluminum isn't too bad.  Also, this case from PE doesn't have a removable top (it's a solid extrusion), which is kind of annoying.





As I mentioned before, I always have a touch of ghetto in my builds.    Here, I couldn't find a rectangular panel mount DC jack that fit this case.  So I just hung a jack off wires out the back.  Not pretty, but it works!  It just sits on my desk anyway, so no big deal.

[flavo]

The wires I used for the volume control are way too long.  I only get about two hours to work on this stuff while my young kids nap, so for now I'll live with the long wires. 

I appreciate the pics. It helps me process. 2 days ago I didn't even know the symble for ohm and just today I found out that PE is for the ground in a 3 prong plug. Haha, I'm learning so much!
Are the long leads bad because a hum could be introduced from it?


 

. The NKK power switch isn't cheap, but it's a high quality power switch and perfect for these amps.

When you say perfect for these amp, is there something we shouldn't be using? I ask because I am trying to build a loose replica of something and it requires a gold on/off switch. So far I have only been able to find a gold 3 way. ebay # 161254411002

[lacro]

Here's some pics of my tpa3110.  Not as clean as Rhing's work, but I like looking at other peoples' work, even when it's not particularly neat.  I figure others might enjoy looking at pics too, so here ya go.

I've been using this tpa3110 for quite a while, but with software volume control.  Thanks to this thread I learned about the cheap and cheerful Panasonic EVJ-Y10F03A54 volume pot.  So that was my little project this weekend, to add a volume pot.  I was worried about the soldering job, but it actually wasn't too bad with a helping hands.  At $6, I say the helping hands is a must if you're going to dabble in DIY.

Here's the "guts" of the unit.  The wires I used for the volume control are way too long.  I only get about two hours to work on this stuff while my young kids nap, so for now I'll live with the long wires.  With the Sure tpa3110 being only $10 and the YJ blue tpa3116 being only $20, it's hard resist the urge to keep building more of these, even though I don't need them.









The case is this aluminum case from Parts-Expres (Part # 320-326).  I thought it would be nice to have all the holes pre-drilled.  But, after my tpa3116 build, I realized drilling aluminum isn't too bad.  Also, this case from PE doesn't have a removable top (it's a solid extrusion), which is kind of annoying.





As I mentioned before, I always have a touch of ghetto in my builds.    Here, I couldn't find a rectangular panel mount DC jack that fit this case.  So I just hung a jack off wires out the back.  Not pretty, but it works!  It just sits on my desk anyway, so no big deal.

Nice job! What caps did you use? Listening impressions compared to 3116?

[rhing]

When you say perfect for these amp, is there something we shouldn't be using? I ask because I am trying to build a loose replica of something and it requires a gold on/off switch. So far I have only been able to find a gold 3 way. ebay # 161254411002

The closest you might find is a brass-plated switch. Have you checked Digikey or Mouser? I just specify what will perform the best. My stuff is pretty plain. That three-way switch seems to be more of a selector switch and not an on-off power switch. For the TPA3116, you really want an SPST switch and a good one that won't arc (i.e., spark) when you switch it on and off.

A good resource for anyone desiring to learn more about building electronic projects is "Starting Electronics Construction" by Keith Brindley. I learned about basic electronics in a very practical manner reading this book. Morgan Jones' "Building Valve Amplifiers" is also a good practical reference on building amps, especially tube amps.

Here's some pics of my tpa3110.  Not as clean as Rhing's work, but I like looking at other peoples' work, even when it's not particularly neat.  I figure others might enjoy looking at pics too, so here ya go.

Nice work Matt. Have you considered Bourns Ferrite beads mentioned in this thread? They'll reduce any RFI from the TPA3110 amp since it doesn't have an output filter. Just slip one bead over each wire between the terminal blocks and your binding posts (4 total).

[matt_garman]

I appreciate the pics. It helps me process. 2 days ago I didn't even know the symble for ohm and just today I found out that PE is for the ground in a 3 prong plug. Haha, I'm learning so much!
Are the long leads bad because a hum could be introduced from it?

Indeed, I just got into the DIY audio electronics after reading the Class D Audio thread here.  Everyone's pictures were immensely helpful, in addition to being fun to look at.

In general, it's good to keep wiring as short as possible.  My (admittedly cursory) understanding is that any electrical signal wire has an opportunity to pick up interference (e.g. EMI), which can reduce signal quality.  You definitely don't want noise (in the electrical signal sense) being introduced at the input level of an amp.  You really don't want it anywhere, but particularly not before feeding it to an amplifier.

Despite that, even with the long leads, I don't hear any obvious sound degradation, although someone with better equipment and/or ears might disagree.

Nice job! What caps did you use? Listening impressions compared to 3116?

For the power supply caps, I used these 1000uF 25V caps from Parts-Express.  I bought those before this thread really got started, so I semi-randomly picked them.  I did buy some more caps mentioned in this thread, but didn't feel like swapping them this time around.

The input DC capacitor is a Pansonic FC 2200uF 25V (DigiKey part number P10284-ND).  That idea came straight from this thread.

As for comparisons to the 3116: too early to tell.  I don't have enough time in with the 3116.  I built the 3116 two weekends ago, but didn't have much time to actually listen to it.  Basically just a "make sure it works" test, followed by a little listening for fun.

Nice work Matt. Have you considered Bourns Ferrite beads mentioned in this thread? They'll reduce any RFI from the TPA3110 amp since it doesn't have an output filter. Just slip one bead over each wire between the terminal blocks and your binding posts (4 total).

D'oh, yes, I actually bought some in my last Digi-Key order (at $0.14/each, why not?), but forgot to install them!

[thaddeussmith]

Removing the stock inductors and installing the Bourns inductors is not a job for the novice. It was a bit tricky without ripping the surface mount pads from the amp board.

if any novices out there need confirmation of this statement, look a page or two back for pictures and commentary about my efforts with these mods. The amp is functional, but not nearly as nice and problem-free as Rhing's.

[rhing]

The mod is working, so mission accomplished. It's these challenges that help you develop techniques and methods. I cut my DIY teeth on modifying Playstation 1 consoles. After modding a few, I felt like a neurosurgeon.

[wired4sound]

Am I the only one using a fuse with these boards?

Poultrygeist, if you do not mind, is the fuse for speaker protection? What is the best way to install speaker protection for the YJ blue board? I noticed that YJ has speaker protection circuit (for about $7+), but not sure how it will affect the sound. Also, which 6N3 preamplifier did you end up using? I would like to get that tube sound, similar to the PrimaLuna Prologue I am currently using. I think I will end up housing the amp and preamp in one enclosure. Your setup seem ideal for me. Thanks!

I am a newbie when it comes putting together electronic gear, but after reading the thread there, I got encouraged to order the YJ blue board. Do I need this part  https://www.parts-express.com/panel-mount-metal-dc-power-jack-21-x-55mm--090-495 in order to power it? I  will not be using battery but will be using this instead https://www.parts-express.com/universal-laptop-power-supply-15~195v-dc-with-5v-usb-charging-port--120-502. Will it work?

[wired4sound]

My fuse is on my power supply: 3A / 250VAC slo-blo.

Rhing, it looks like it is a lot cleaner to use on on-board power supply rather than a laptop charger. Which power supply did you end up using? Was it hard to install? You finished enclosure looks great! I may end up building two amps, one with preamp and one without.

Anybody tried building a 6-channel amp (blue board) using one power supply?

[wushuliu]

I completed a second Yuan Jing 2.0 blue amp build. In this case, I used a Panasonic EVJ 50kohm log taper pot just like lacro's standalone volume control box. These work really well with these Texas Instruments Class D amps and they are very reasonably priced at $1.70 each from Digikey (PN P2G1503-ND).

After receiving the amp module within a week from Yuan Jing, I first removed the stock DC decoupling caps, the input caps and the inductors to begin the upgrade process. Removing the stock inductors and installing the Bourns inductors is not a job for the novice. It was a bit tricky without ripping the surface mount pads from the amp board. I thought I could just heat the solder joints simultaneously with two solder irons and the inductors would fall off. However, the solder that Yuan Jing uses hardly reflows. I had to use a toothpick to apply some gel flux paste to the solder joints and heat the joints with my solder iron while very gently lifting the stock inductors off the board. The space is very tight, so depending on the size of your solder iron, some people may need to temporarily remove adjacent caps to make more room and avoid burning anything. With patience and a gentle tug on the inductors while reflowing the solder joints, I was able to neatly remove them all and keep the surface mount pads in place. After that, I had a lot of cleanup with alcohol and cotton swabs. You can see I couldn't get it spotless, but it was good enough.



Next, I populated the board with the following:

• Panasonic FM electrolytic caps, DC decoupling............Mouser 667-EEU-FM1E152
  ....................................... .....................................Di gikey P12380-ND
• Wima MKP10 film caps, input coupling.......................Mouser 505-M101.0/250/5
• Bourns 10uH inductors, output filter........    ..............Mouser 652-2100HT-100-V-RC
  ....................................... .....................................Di gikey 2100HT-100-V-RC-ND

To mount the inductors, I snipped off the excess lead length and bent the legs to create "feet" to make more contact with the solder pads on the board. I applied generous amounts of solder for good electrical and mechanical connections. With a little work, the inductors fit neatly on the board. I like the fact that the layout has two outside inductors sitting forward from the two inside inductors. This created a bit more room to fit the inductors without having to position them at an angle.



I wired up the amp with some Belden 88641 shielded twisted pair hook-up wire and tied the shields to the source end grounds only (i.e., RCA jack ground tabs). For mounting the board, I used 4-40 Nylon standoffs and screws.




Later, I added a small green LED to indicate when the amp is powered on. I have a 5.1kohm 1/4 watt resistor wired in series with the LED to keep it bright enough to see in daylight, but not too bright during night time listening. I had drilled a pin hole through the face plate to all the green LED to shine through.



I have been burning this amp in using my Alan Parsons Sound Check 2 test CD, which has multiple test tones, frequency tone sweeps and uncompressed music tracks. I try to put as much as 10-20 hours of burn-in time with this CD playing in repeat mode. It really gives the amp a workout, and it seems to shorten the burn-in process.



I've been listening to music off and on since yesterday, and I have to say these mods really add a noticeable level of refinement to the sound quality. The music is more natural-sounding with more detail and transparency. The stock amp is nice, but the mods really revealed how veiled the sound is. The amp sounds smoother, especially with strings, cymbals and vocals.

Why not replace the other 2 1ufs? FWIW I have some Radio Shacks in mine. They're a good PP cap FTM.