Sorry, I made a mistake. For Rev C, there are three 470uF 16V caps but only one for both Rev A and B.
Thank you! I really appreciate people like you who are willing to help!
When the amp comes I will let you know what version is...
When the amp comes I will let you know what version is...
Thank you! I really appreciate people like you who are willing to help!
When the amp comes I will let you know what version is...
You are most welcome, my friend. 🙂
The amp has come, on the board is written 130728pcb... What rev. is that?
Does it have two relays and 11 electrolytic capacitors?
Here is the picture
http://s23.postimg.org/xokgu441n/lp2020a.jpg
Errr... That's an awfully small picture. Anyway, yeah it is a Rev C.
I have some different values, for example c28,c29 is 100uf 25v or c3 is 680uf 16v... So do I need to order parts with same value as it is or that what you wrote?
I have some different values, for example c28,c29 is 100uf 25v or c3 is 680uf 16v... So do I need to order parts with same value as it is or that what you wrote?
That's fine. Lepai does not use a standard value throughout their amps even of same model.
By the way, C28 and 29 are ALWAYS 100uF 25V or 16V regardless of version.
As for C3, it can be either 470uF or 680uF. It doesn't matter.
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I have no experience, I m still learning... So I can order parts like you wrote, it will work fine?
I have no experience, I m still learning... So I can order parts like you wrote, it will work fine?
Yeap... It should. Provided you don't reverse the polarity of the caps.
How can i measure the dc offset? Pin 10 to AGND (Pin 3,7,16)? There i have 2,5 Volt !?! Could that be or where to measure it? I have LP-2020A+ PCB. Thx!Try a dc offset adjustment. Get it as close as possible to 0V.
How can i measure the dc offset? Pin 10 to AGND (Pin 3,7,16)? There i have 2,5 Volt !?! Could that be or where to measure it? I have LP-2020A+ PCB. Thx!
You measure on each output channel between the output signal and ground, with no signal into the amp.
Just got one of these. It cuts out sometimes when I bring the volume passed a certain point. Maybe the power supply? It came with 12v 2A plug.
Also what speakers would you recommend to go with this? Is there an ideal impedance?
Currently I have it hooked up to a single speaker cone from an old pye radio but there is distortion.
Also what speakers would you recommend to go with this? Is there an ideal impedance?
Currently I have it hooked up to a single speaker cone from an old pye radio but there is distortion.
Just got one of these. It cuts out sometimes when I bring the volume passed a certain point. Maybe the power supply? It came with 12v 2A plug.
Also what speakers would you recommend to go with this? Is there an ideal impedance?
Currently I have it hooked up to a single speaker cone from an old pye radio but there is distortion.
Well, there is not really an "ideal" speakers to go with the Lepai. I would say anything between 6 to 8 ohms works fine. I have used my Lepai to drive a Cerwin Vega 3-way floorstanders with 12" woofers without any issues. Currently, it is driving a pair of 3-way Onkyo floorstanders which I prefer.
The 12V 2A is sufficient but a higher current power supply will work better. As for the cut-off problem which you are encountering, yes, most likely it is due to the power supply.
As for the distortion, there are many factors and possibilities. Do you have another pair of speakers to test. If so, switch around to see if the amp is causing it.
OK Thanks. Yes I have other speakers, so I'll test on them.
Would 4 ohms work too? Not too familiar with speaker impedance, would 4 ohms or 8 ohms be better?
Also if I decide to only use 1 speaker, does this change things?
Would 4 ohms work too? Not too familiar with speaker impedance, would 4 ohms or 8 ohms be better?
Also if I decide to only use 1 speaker, does this change things?
Would 4 ohms work too? Not too familiar with speaker impedance, would 4 ohms or 8 ohms be better?
Also if I decide to only use 1 speaker, does this change things?
Personally I prefer 8 ohms because low impedance load stresses the amp to put out more current, and that can be bad especially if Lepai is incapable of putting out the amount of current the low impedance speaker demands.
Never connect to just one speaker. You might damage your amp.
one speaker
4 ohm speakers are tolerable, if you do not try to get head banging levels of volume. Put a resistor on the other channel output of approximately the DC resistance of the speaker you are using. Happy Ears!
4 ohm speakers are tolerable, if you do not try to get head banging levels of volume. Put a resistor on the other channel output of approximately the DC resistance of the speaker you are using. Happy Ears!
I'm new to these boards but have been tinkering with various amps and speaker set-ups for bicycle sound systems for a few years now.
I recently purchased two of these amps.
One I accidentally fried due to soldering the negative and positive connections to the wrong parts of the pin(my soldering skills blow and I'm still figuring out these electrical symbols.)
The second one I figured out and got to work right and it sounds great.
Problem is I'm getting sound out of the right channels, but the left is pretty much dead air.
Is there any particular way to get sound out of those channels without resorting to getting a third?
I've still got the first one I bought here and there should still be a few, usable pieces left on board.
I recently purchased two of these amps.
One I accidentally fried due to soldering the negative and positive connections to the wrong parts of the pin(my soldering skills blow and I'm still figuring out these electrical symbols.)
The second one I figured out and got to work right and it sounds great.
Problem is I'm getting sound out of the right channels, but the left is pretty much dead air.
Is there any particular way to get sound out of those channels without resorting to getting a third?
I've still got the first one I bought here and there should still be a few, usable pieces left on board.
Note, these are on-sale....again....for a butt cheap $20 USD..........really a good value I'd guess, considering how much it would cost you to build one from scratch........just saying.
______________________________________________________Rick.........
______________________________________________________Rick.........
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