Had another thread for amps and was able to narrow down what I'm after. Was going to go 2.1 but, probably overkill for what will be 95% 8-Bit video game sound from pre-1993.
Anyways... looking at 2 which are basically the same. I chose these because the volume knob is at the front and all the power/in/outputs at the back. I want the volume knob on the outside of the cabinet which is tricky when the stereo input jack is at the front as well. Other option would be to de-solder the potentiometer and add wires a few inches long I suppose. Plus, I plan to use a laptop PSU and these have an input jack at the back so makes things easy.
Question I had though, when looking at the two, one has copper coiled rings, and the other flat black blocks. Because I'm a curious sort, what are those and which are better (and why)?
Anyways... looking at 2 which are basically the same. I chose these because the volume knob is at the front and all the power/in/outputs at the back. I want the volume knob on the outside of the cabinet which is tricky when the stereo input jack is at the front as well. Other option would be to de-solder the potentiometer and add wires a few inches long I suppose. Plus, I plan to use a laptop PSU and these have an input jack at the back so makes things easy.
Question I had though, when looking at the two, one has copper coiled rings, and the other flat black blocks. Because I'm a curious sort, what are those and which are better (and why)?
The first one has shielded bobbin inductors. Their value is a little high for the TPA3116 and 4-8 Ohm loads. Their small size means they run the risk of saturating at high power output.
The second board has toroid inductors of unknown value. They will handle higher power before saturating. They aren't shielded, but that shouldn't be an issue.
All things being equal, I would go with the second board.
The second board has toroid inductors of unknown value. They will handle higher power before saturating. They aren't shielded, but that shouldn't be an issue.
All things being equal, I would go with the second board.
Agree the amp doesn't need a fan; many TA2024 and TPA3116 implementation don't even have heatsinks; just some copper on the PCB.
LED runs on max 2V to 3V per LED in series, often a current-limited supply of 20mA (plus minus a few hundred percent, like how things typically are in science and engineering)
Fans typically draw 3-digit milliamps of 5V and 12V
You can tap the 12V or 24V or whichever amp power supply you choose from pretty much everywhere. But the fan can inject noise into the circuit.
And keep the light, or you'll be tearing hairs when troubleshooting.
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Well, if no heat issues, no worries. 
Figured I have a half dozen small fans laying around, big as 120mm and small as what's on a Raspberry Pi... LED I had no use for, figured if cooling helps, replace with a fan.
I assume the LED is on or off, not blinking error codes so, if replaced with a fan, then light on/off would be the same as fan on/off. Any troubleshooting beyond that or bulged capacitors, I wouldn't have a clue about.
And only reason I know about capacitors is because I have a pair of Samsung 204B 4:3 monitors, both with the same issues and same bulged/leaking CapXon cheap capacitors. Had to research to know what ones to buy... hopefully I picked the right ones.
Figured I have a half dozen small fans laying around, big as 120mm and small as what's on a Raspberry Pi... LED I had no use for, figured if cooling helps, replace with a fan.
I assume the LED is on or off, not blinking error codes so, if replaced with a fan, then light on/off would be the same as fan on/off. Any troubleshooting beyond that or bulged capacitors, I wouldn't have a clue about.
And only reason I know about capacitors is because I have a pair of Samsung 204B 4:3 monitors, both with the same issues and same bulged/leaking CapXon cheap capacitors. Had to research to know what ones to buy... hopefully I picked the right ones.
So I ended up buying the amp in the bottom photo... though that was June 4, it's now July 12, and still no sign of it.
As mentioned, I was doing the caps in my monitors, which went great... both monitors are bright and turn on fast now.
Was wondering, since it was an easy and relatively cheap upgrade, would these cheap eBay amps (if it ever shows) benefit from better caps? I keep seeing mentioned that recapping improves things but never really how, or by how much unless someone if upgrading some old amp from the '70s or something.
Would upgrading components help these cheap amps? or being cheap amps, it may help but not enough to notice?
That said, if no amp in another week... I think I may up the budget and get something like a Pyle PFA300 or Lepy/Lepai LP-2020A (I guess Lepai is better then Lepy but Lepai seems harder to find and more costly).
As mentioned, I was doing the caps in my monitors, which went great... both monitors are bright and turn on fast now.
Was wondering, since it was an easy and relatively cheap upgrade, would these cheap eBay amps (if it ever shows) benefit from better caps? I keep seeing mentioned that recapping improves things but never really how, or by how much unless someone if upgrading some old amp from the '70s or something.
Would upgrading components help these cheap amps? or being cheap amps, it may help but not enough to notice?
That said, if no amp in another week... I think I may up the budget and get something like a Pyle PFA300 or Lepy/Lepai LP-2020A (I guess Lepai is better then Lepy but Lepai seems harder to find and more costly).
You could change the local supply caps to low ESR types like Panasonic FC/FM. Would you notice any difference? Maybe, maybe not. Depends on how crappy the original caps are to begin with.
Then there's the rabbit hole of input coupling (DC blocking) capacitors. I'll let you go on that journey by yourself.
Then there's the rabbit hole of input coupling (DC blocking) capacitors. I'll let you go on that journey by yourself.
What do the caps change anyways?
I see posts saying how it improves the sound... but not much 'how' the sound is improved... will I hear stuff I didn't hear before? better tone? less tinny? less distortion? all of the above?
On a good amp of course... I suspect a $15 amp won't improve by much regardless what I do, but learning so kinda curious.
I'd love to build a simple basic amp if I can find a good diagram for one. Was looking at those Lepy/Lepai amps, with good components I suspect those would be pretty good, no?
I see posts saying how it improves the sound... but not much 'how' the sound is improved... will I hear stuff I didn't hear before? better tone? less tinny? less distortion? all of the above?
On a good amp of course... I suspect a $15 amp won't improve by much regardless what I do, but learning so kinda curious.
I'd love to build a simple basic amp if I can find a good diagram for one. Was looking at those Lepy/Lepai amps, with good components I suspect those would be pretty good, no?
When i re-cap things, whether it's audio or not, it's more for reasons of reliability / longevity, rather than "audio quality".
Cheap crap chinese caps WILL die sooner rather than later, especially in mid-to-high temperature and high ripple situations - think power supplies here.
That being said, i clearly recall having re-capped a dbx DriveRack active crossover, which had all the DC blocking caps on the output bloaded - non-polarized green-sleeve CapXon's...
Nope, i don't trust non-Japanese caps as far as i can throw them.
Cheap crap chinese caps WILL die sooner rather than later, especially in mid-to-high temperature and high ripple situations - think power supplies here.
That being said, i clearly recall having re-capped a dbx DriveRack active crossover, which had all the DC blocking caps on the output bloaded - non-polarized green-sleeve CapXon's...
Nope, i don't trust non-Japanese caps as far as i can throw them.
Actually... the two Samsung monitors I had, had CapXon's... I replaced with Nichicon for most of it, and a Panasonic for 1 because was the only one I could find that matched the needed specs.
In both cases, tops were buldged out and a bit of stuff leaking out as well.
Not audio, but I definitely researched which brands were better because wasn't getting more CapXons that's for sure.
But otherwise, if those monitors worked, same as any audio/video device, I wouldn't give a second thought about opening it and replacing/upgrading parts. I only do that when stuff breaks, which is why I wondered how much of an improvement is there to warrant the work on something that's currently working.
In both cases, tops were buldged out and a bit of stuff leaking out as well.
Not audio, but I definitely researched which brands were better because wasn't getting more CapXons that's for sure.
But otherwise, if those monitors worked, same as any audio/video device, I wouldn't give a second thought about opening it and replacing/upgrading parts. I only do that when stuff breaks, which is why I wondered how much of an improvement is there to warrant the work on something that's currently working.
As i mentioned, for me it's more of a "peace of mind" thing. That, and the fact that i somewhat enjoy tinkering with stuff
But, y'know, if i re-cap something preemptively, i see it as saving myself the headache down the road. Kinda like "as stock, odds are it WILL fail in the not-very-distant future; with Japanese caps, i'll likely end up getting rid of it before it dies on me, much further down the line"
And as i've mentioned, i've seen crap caps bloated in line-level audio signal paths(!!!). If that's not a testament to their <ahem> "reliability", and a motivation to get rid of'em, i don't know what is
... But that's just me, i'm weird like that...
But, y'know, if i re-cap something preemptively, i see it as saving myself the headache down the road. Kinda like "as stock, odds are it WILL fail in the not-very-distant future; with Japanese caps, i'll likely end up getting rid of it before it dies on me, much further down the line"
And as i've mentioned, i've seen crap caps bloated in line-level audio signal paths(!!!). If that's not a testament to their <ahem> "reliability", and a motivation to get rid of'em, i don't know what is
... But that's just me, i'm weird like that...
Yeah I can see that....I haven't even gotten my amp yet and already asking about recapping.
If it were a $100+ amp though, I wouldn't touch it.
I just figured with threads about recapping, there was some advantage to doing so, audibly speaking... like a big noticeable improvement in sound or power. Was curious to know what that improvement would be.
I do plan to build an alarm clock for my bedside table. I always listen to music at bed time with my headphones, and would love an audiophile quality music player just for my headphones. Figured a RaspPi and audiophile quality components (DAC and such) but will be hopefully high-end parts when I get them already so won't be a need to solder in new caps and such.
But... arcade cabinet first.
If it were a $100+ amp though, I wouldn't touch it.
I just figured with threads about recapping, there was some advantage to doing so, audibly speaking... like a big noticeable improvement in sound or power. Was curious to know what that improvement would be.
I do plan to build an alarm clock for my bedside table. I always listen to music at bed time with my headphones, and would love an audiophile quality music player just for my headphones. Figured a RaspPi and audiophile quality components (DAC and such) but will be hopefully high-end parts when I get them already so won't be a need to solder in new caps and such.
But... arcade cabinet first.
If it were a >$100 amp, i'd be disgusted to see any non-japanese caps. And yet, i've seen crap caps in gear worth a good several hundreds. Like that dbx active crossover i mentioned earlier... Or the Lelon / Meritek / JunFu that were stock in my MOTU 896mk3 Hybrid audio interface ("still" retails a bit over a grand brand new, i paid around 700 for it used).
BTW... just found this one, post#2 talks about how the amp sounds after upgrading the caps on a Lepai mini amp. Pretty interesting. Hard to find those amps though, lots posted as Lepai but actually Lepy which is very annoying. Parts Express has them, USA site, ships to Canada but I think I have to go through most of the purchasing steps to get any sort of shipping cost, plus possible import fees so not worth it for me... but if in 2 weeks my eBay amp is a no show, I think I'll have to go for the Lepai.
Modding the Lepai T2020A+ - Techtalk Speaker Building, Audio, Video Discussion Forum
Modding the Lepai T2020A+ - Techtalk Speaker Building, Audio, Video Discussion Forum
Haha... go figure, I bought a few things from different sellers June 4th, day after the ETA (53 days) I launched the 'item not received' complaints... and this afternoon everything showed up.
CAP question... when dealing with cheap eBay China boards, how often/common/possible is it to get stuff with fake caps?
Was surprised to see SANYO 1000uf 35v caps, was expecting some no name brand ones. The wee small ones around the heat sink I can't read because the info is facing the wrong way. They're darker green with white lettering saying non-polar... then one by itself, also very small, black/gold and I think says 1uf 50v... will probably take the heat sink off when home, make sure some thermal paste on it and see if can put on straight... won't make it sound better but being crooked bugs me. When off I can see the brands/info of the caps more.
So.. do things come with fake caps? Saw a few YouTube vids that mention that in passing.
How do you know which caps are for sound and which for power? Like... if this were a better board for example, how would you know which caps to replace with general purpose caps and which would be audio quality caps?
For the below, I assume the 3 large are power, and the small ones are audio?
(mine is the same as this, except the single cap to the right is a black/gold cap)
CAP question... when dealing with cheap eBay China boards, how often/common/possible is it to get stuff with fake caps?
Was surprised to see SANYO 1000uf 35v caps, was expecting some no name brand ones. The wee small ones around the heat sink I can't read because the info is facing the wrong way. They're darker green with white lettering saying non-polar... then one by itself, also very small, black/gold and I think says 1uf 50v... will probably take the heat sink off when home, make sure some thermal paste on it and see if can put on straight... won't make it sound better but being crooked bugs me. When off I can see the brands/info of the caps more.
So.. do things come with fake caps? Saw a few YouTube vids that mention that in passing.
How do you know which caps are for sound and which for power? Like... if this were a better board for example, how would you know which caps to replace with general purpose caps and which would be audio quality caps?
For the below, I assume the 3 large are power, and the small ones are audio?
(mine is the same as this, except the single cap to the right is a black/gold cap)
You can follow the traces, but usually the values and voltage ratings are a dead giveaway (these relating directly to physical size), so the big ones will most likely be on the power rail.
That being said, despite what the sleeve says, those are most definitely NOT Sanyo.
First of all, they have (or rather, had) a K-shaped vent stamp.
http://i.ebayimg.com/images/g/FikAAOSwa-dWsn6G/s-l1600.jpg
Second, Sanyo sold their ("wet") electrolytic business to Suncon back in 2009.
Third, "audio quality" caps (especially if we're talking electrolytics) is just pure marketing bulls**t.
But either way, the roles of components on amp boards like these (single- or double-sided, tops) can more often than not be deduced by following where the copper traces go, and maybe checking the datasheet of the chip to see the function of the pins.
PS: Not quite sure how "helpful" those non-polar caps are there, because the side that goes to the amp will be biased to some positive voltage anyway, so... I dunno
That being said, despite what the sleeve says, those are most definitely NOT Sanyo.
First of all, they have (or rather, had) a K-shaped vent stamp.
http://i.ebayimg.com/images/g/FikAAOSwa-dWsn6G/s-l1600.jpg
Second, Sanyo sold their ("wet") electrolytic business to Suncon back in 2009.
Third, "audio quality" caps (especially if we're talking electrolytics) is just pure marketing bulls**t.
But either way, the roles of components on amp boards like these (single- or double-sided, tops) can more often than not be deduced by following where the copper traces go, and maybe checking the datasheet of the chip to see the function of the pins.
PS: Not quite sure how "helpful" those non-polar caps are there, because the side that goes to the amp will be biased to some positive voltage anyway, so... I dunno
I was thinking of buying a Rubycon cap kit, of a variety of values and such to play around with and learn with on a breadboard an LM386 chip I have... so, probably for what this is, replacing all the caps with gen purpose Rubycon would be fine?
... well, if I find a kit that includes the needed values.
Doubt it will improve anything, but saw a review on a cheap amp with a fake Sanyo and cap blew after 2 minutes and shot the top off like a bullet, so... figured recap... plus I need the practice.
I won't use a 24v psu, I have a 19v laptop psu for it. The video I watched was using a 24v with 25v caps which he later recapped to 50v.
at around 13:10
Ebay 'Breeze Audio' TPA3116 Mini Amplifier Review - YouTube
... well, if I find a kit that includes the needed values.
Doubt it will improve anything, but saw a review on a cheap amp with a fake Sanyo and cap blew after 2 minutes and shot the top off like a bullet, so... figured recap... plus I need the practice.
I won't use a 24v psu, I have a 19v laptop psu for it. The video I watched was using a 24v with 25v caps which he later recapped to 50v.
at around 13:10
Ebay 'Breeze Audio' TPA3116 Mini Amplifier Review - YouTube
PS: Not quite sure how "helpful" those non-polar caps are there, because the side that goes to the amp will be biased to some positive voltage anyway, so... I dunno
Those would be the 4 small ones left of the knob, correct?
First I've come across non-polar... if recapped, I guess that means I need to find non-polar to match, correct? should they be non-polar to begin with?
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