Thanks for pointing out... There IS something which I did to all my Lepais. That is I have replaced all stock inductors to high current shielded ones. Perhaps this is why I don't get interference from my FM radio.
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It doesn't matter. Both RCA connectors and 3.5mm jacks of Lepai are linked internally.
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Thanks KopiOkaya.
I need to power an LED somehow for my VU Meter from the LP2020. It has no resistor inside, so according to the specs it can be 5v or 12v.
Originally planned on using seperate USB power but this isn't going to work. My thought was I could solder onto the metal "tabs" on the outside of the power cord jack. This should provide me with 12v I believe.
Does anyone see any problems with doing that? I thought it would be better than splicing into my power supply cable.
I need to power an LED somehow for my VU Meter from the LP2020. It has no resistor inside, so according to the specs it can be 5v or 12v.
Originally planned on using seperate USB power but this isn't going to work. My thought was I could solder onto the metal "tabs" on the outside of the power cord jack. This should provide me with 12v I believe.
Does anyone see any problems with doing that? I thought it would be better than splicing into my power supply cable.
Is the LED the only thing you need power for, or the VU meters too? 12vdc will kill a LED almost instantly if no limiting resistor is used. 5v is a safe voltage without using a resistor.
I used a 1k ohm resistor as the instructions stated. I hooked it up and nothing worked for the backlight. This is just to power the LED. According to my test light I had the wires in the correct location.
VU meter works though and looks cool. Only downside is unless you crank it up, don't see much movement of the needle.
VU meter works though and looks cool. Only downside is unless you crank it up, don't see much movement of the needle.
After i played my Lepai, it doesn't getting better (as i said last week it's getting hot and pop-off soung louder), i guess there's something wrong with it.
So, i choose to mod it again, bypassing tone control, change input and output connector..tralaaa... It's better now, Love it more now..
So, i choose to mod it again, bypassing tone control, change input and output connector..tralaaa... It's better now, Love it more now..
An externally hosted image should be here but it was not working when we last tested it.
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Best (cheap) power supply for Lepai 2020
New user here. I just bought one of these amps and LOVE it. Believe it or not, they are powering a pair of Boston Acoustic VS260 bookshelf speakers in a nearfield PC setup and it sounds great!
Quick question...I'd like to simply upgrade the power supply to get a little more headroom and slightly louder listening levels with same low distortion at lower lvls.
I was originally considering just replacing the stock 12v 2a (some say it's actually a 1.5a) power supply with a 12v 5a version. After doing a little reading, some people were saying that the 12v w/ extra amperage really doesn't do much and the key is supplying more voltage, 13.5v to be exact, for the stock Lepai.
The problem is, I can't really seem to find a cheap 13.5v / 3-5amp switching power supply!!! There are plenty of 14v/4a for <$10, but I read going over 13.5v starts to degrade SQ.
I really want to stay cheap and avoid upgrading to a indeed/topping unit that can handle the 14v b/c (surprisingly enough) I like the treble tone control on the leapi and b/c I'm cheap!!
Any ideas? Thanks in advance!
New user here. I just bought one of these amps and LOVE it. Believe it or not, they are powering a pair of Boston Acoustic VS260 bookshelf speakers in a nearfield PC setup and it sounds great!
Quick question...I'd like to simply upgrade the power supply to get a little more headroom and slightly louder listening levels with same low distortion at lower lvls.
I was originally considering just replacing the stock 12v 2a (some say it's actually a 1.5a) power supply with a 12v 5a version. After doing a little reading, some people were saying that the 12v w/ extra amperage really doesn't do much and the key is supplying more voltage, 13.5v to be exact, for the stock Lepai.
The problem is, I can't really seem to find a cheap 13.5v / 3-5amp switching power supply!!! There are plenty of 14v/4a for <$10, but I read going over 13.5v starts to degrade SQ.
I really want to stay cheap and avoid upgrading to a indeed/topping unit that can handle the 14v b/c (surprisingly enough) I like the treble tone control on the leapi and b/c I'm cheap!!
Any ideas? Thanks in advance!
Found this on eBay, but I'm not sure the plug will fit:
Creative UA 1450 UA1450 AC Adapter 13 5VAC 5A Power Supply | eBay
but the ID of this one is 2.5mm whereby the lepair needs 2.1mm...hmmm
Quick and dirty - cheap.
""<<http://www.digikey.com/product-detail/en/ECO-S1CA822BA/P6441-ND/131277>>""
Hi,
Just put this cap between the two wires in the link from the wall wart power supply to the plug that goes into the back of the 2020A+ amp.
Cap (+) pin to (+) wire, (-) pin to (-) wire.
No need to open chassis or anything.
Happy Ears!
Al
""<<http://www.digikey.com/product-detail/en/ECO-S1CA822BA/P6441-ND/131277>>""
Hi,
Just put this cap between the two wires in the link from the wall wart power supply to the plug that goes into the back of the 2020A+ amp.
Cap (+) pin to (+) wire, (-) pin to (-) wire.
No need to open chassis or anything.
Happy Ears!
Al
Thanks for the idea! Being almost a complete noob when it comes to DIY audio, what exactly will the cap do here? Has anyone done this before, and are there any instructional references for this?
Q & D - backpages
Hi LJB,
You want answers
Read these blogs. We want to share information. You want expert personal guidance. That is less easy to find... Read and read until you understand
In a power supply, a DC (Direct Current) filter network makes the DC smoother and more stable. We call it "stiff". All that is wanted is less noisy DC.
Manufacturers want products that are good enough to sell at a nice margin. "Return On Investment" is what business is about. Adding a two dollar cap that does not fit in the "package" is not a good business decision.
Capacitors keep the Voltage more stable, reducing noise.
Chokes keep the Current more stable, also reducing noise.
Resistors reduce the Voltage, and also cause a tiny delay in the noise from a series of caps, further smoothing the DC.
The Panasonic TS-HA Capacitors are very good for power supply filters. They have very low ESR (Equivalent Series Resistance) making their functioning better at higher frequencies.
The bandwidth of the TA2020-020 chip is 22Hz to 22KHz. The chip clock is about (~) 300KHz. Noise in the power supply both at the audio bandwith and at the digital speeds can reduce the clarity and power of the unit.
We can do better
Welcome to DIY. We want better Sound, not just more profits!
Happy Ears!
Al
Hi Siles,
Gee, that sounds like "High Styles"... In 1991 I was a software engineering manager at IT&T. What were you doing to now use that year in your ID? My son was born in 1972... maybe you are younger? I am a 1947. KopiOkaya is a good guy. He has been very engaging. It is dawning on Sunday morning here in Dallas, Texas (yes, where JFK was killed, in 1963...)
Anyway, I have been building electronics since 1958, when my dad bought me a Heathkit xtal (hip geek speak spelling for crystal) radio kit
I would reorder the priorities of Kopi's list. I have been building audio stuff to listen to in my home for decades. My priorities are just as arbitrary as any (and EVERY) one else's, but, since they are MINE I like to share them, OK?
OK, first off, many on this list like to buy bigger, fancier power supplies. The simple truth is all that is needed is a Power Supply Filter. It can be in a separate box. Fitting everything into the 2020A+ is a simple style statement. We do not need to cram everything into the same box for any technical reason. The Switching Power Supply can be in the next room. It is regulated DC, it does not care how long the wires to the amp are. The ~12V supply of 2 or 3 amps supplied by some vendors is adequate, but a simple big cap can be attached to the wires from the wall wart to the amp:
Carefully split the two parallel wires apart near the connector (a few inches - to allow the filter network to be close, but moveable) and then cut only the insulation on the (-) wire then bare some copper by pulling the insulation away from the cut and solder the (-) pin or wire of the cap to it.
Then cut only the insulation on the (+) wire farther away from the connector and attach the positive pin or wire to it.
After you have the cap connected, push the insulations back toward the cuts.
I have had my 2020A+ for a few months. I only opened up the case to do some "damage" to the amp itself, last week.
The reason I added the Power Supply Filter first is the Ancient Truth about engineering:
"Garbage IN, Garbage OUT".
Yes, you can change things in the output network in the amp, but, only after you have fixed everything from the power supply filter to that stage, first
And the stuff coming from what ever source you are using cannot be improved, only be made LOUDER, not better. Tone Controls are simple toys for the low tech to try and make the system sound better. They can, but, only up to a certain level... if you are going to waste so much of the rest of your life enjoying playing Audio Design and Implementation Genius, these are some helpful thoughts
Getting Started: when your 2020A+ arrives, admire the beautiful simple package and carefully install it in you current system and turn it on and listen. After a few days (or weeks) of "Break In" you can do some initial things to find out what may need improving.
To check the Power Supply: The TA2020-020 chip can function from 8.5 to 16 volts. In my speakers, 100 dB can be achieved by one watt output. That is 9.48 Volts and 0.3 Amps in my current version of my "Lepai Nano Godzilla Amp"
(to be continued...)
Al
Hi LJB,
You want answers
Read these blogs. We want to share information. You want expert personal guidance. That is less easy to find... Read and read until you understand In a power supply, a DC (Direct Current) filter network makes the DC smoother and more stable. We call it "stiff". All that is wanted is less noisy DC.
Manufacturers want products that are good enough to sell at a nice margin. "Return On Investment" is what business is about. Adding a two dollar cap that does not fit in the "package" is not a good business decision.
Capacitors keep the Voltage more stable, reducing noise.
Chokes keep the Current more stable, also reducing noise.
Resistors reduce the Voltage, and also cause a tiny delay in the noise from a series of caps, further smoothing the DC.
The Panasonic TS-HA Capacitors are very good for power supply filters. They have very low ESR (Equivalent Series Resistance) making their functioning better at higher frequencies.
The bandwidth of the TA2020-020 chip is 22Hz to 22KHz. The chip clock is about (~) 300KHz. Noise in the power supply both at the audio bandwith and at the digital speeds can reduce the clarity and power of the unit.
We can do better
Welcome to DIY. We want better Sound, not just more profits!
Happy Ears!
Al
READ the wiki here the Lepai...FIRST.. then IF you must substitute a Cap do it inside the Contraption .. as per the wiki info.
Also read on the Power Supply suggestions therin.
12 v @5amps is "fine' Under any circumstance.. as in anything more is in the mind of the beholder... alone.
There is sooo much nonsense re these things it's astounding. Especially given what they actually are: cheap, sloppy Fake copies.
Each one with a slightly differing sound from another.
Bottom of the market Chinese Quality Control at it's finest.
Also be aware these have a Short life expectancy .. so don't be going too nuts.
Why this response?
Wiring a cap into the power cord isn't a big deal, as long as potential shorts are dealt with at the same time. It's not a bad idea for someone wary of getting into the guts of their Lepai.
"cheap, sloppy Fake copies"? Maybe so, but also satisfying and inexpensive little amplifiers. I'd guess they actually sound better than the usual buyer expects them to.
Do you have MTBF data?
Mine is 3+ years old, gets daily use, and works like new. And sounds good. Not too shabby for a Jackson.
Wiring a cap into the power cord isn't a big deal, as long as potential shorts are dealt with at the same time. It's not a bad idea for someone wary of getting into the guts of their Lepai.
"cheap, sloppy Fake copies"? Maybe so, but also satisfying and inexpensive little amplifiers. I'd guess they actually sound better than the usual buyer expects them to.
Do you have MTBF data?
Mine is 3+ years old, gets daily use, and works like new. And sounds good. Not too shabby for a Jackson.
Mine isn't 3+ years old but I have 10 sets being abused in rural schools, so far only one got replaced. And that was because somebody connected the power wrongly and shorted the chip.
Al vs the Alligators
Some folks do not like fixing a problem effectively outside the box. That is a style statement, opinion, not an engineering suggestion.
Anyone's opinion of a product's worth and quality is an opinion, and may be shared. We each must decide if we agree, or not.
Engineering is not only a debate, it is a process. After you cure the problem, you may look for a way to integrate it into the box, but make sure you are happy with your opinion, first.
Putting a cap into the wires from the wall wart to the 2020A+ can be undone and repaired with simple electrical tape. Integrating a part into the unit without testing the effect first is risking damage to the unit - unnecessarily.
Follow your instincts, not other's opinions.
Some of my opinions are occasionally stupid. Not all
We all enjoy our opinions. We are all not well seasoned circuit modifiers. Some are.
Experience is having your butt bitten by every alligator in the swamp, not simply disliking alligators, fearing them. Then, proceeding accordingly.
Happy Ears!
Al
Some folks do not like fixing a problem effectively outside the box. That is a style statement, opinion, not an engineering suggestion.
Anyone's opinion of a product's worth and quality is an opinion, and may be shared. We each must decide if we agree, or not.
Engineering is not only a debate, it is a process. After you cure the problem, you may look for a way to integrate it into the box, but make sure you are happy with your opinion, first.
Putting a cap into the wires from the wall wart to the 2020A+ can be undone and repaired with simple electrical tape. Integrating a part into the unit without testing the effect first is risking damage to the unit - unnecessarily.
Follow your instincts, not other's opinions.
Some of my opinions are occasionally stupid. Not all
We all enjoy our opinions. We are all not well seasoned circuit modifiers. Some are.
Experience is having your butt bitten by every alligator in the swamp, not simply disliking alligators, fearing them. Then, proceeding accordingly.
Happy Ears!
Al
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