Yea, I think my definition of "good source" is far looser than you guys..
I have a modded x-fi, which I consider "GOOD" source
I don't really plan to get anything above this.. as I feel diminishing returns on audio equipment especially the "unmeasurable" kind is tough to swallow.
I mean, new CPU, benchmarks higher.. new audio equipment, yea, sounds m0ar warm... $800 please... thankyou, here you go, come back next year when we release m0ar warmness
I have a modded x-fi, which I consider "GOOD" source
I don't really plan to get anything above this.. as I feel diminishing returns on audio equipment especially the "unmeasurable" kind is tough to swallow.
I mean, new CPU, benchmarks higher.. new audio equipment, yea, sounds m0ar warm... $800 please... thankyou, here you go, come back next year when we release m0ar warmness
well... the 2.2uf caps are in "what little" schematic we "do" have...
But yea, if you bypass and have a really good source.. I think just direct shoot would be "fine.." although you'd still at least need those 0.01uf in the loop for noise control going over "distance"
I cannot see C20 and C21 in the schematic in post #1.
In post #104 I see C20 and C21 still in place.
Post #3 reports: "The first mod I did was to replace C20 & C21 with film caps." but in post #7 they seem to have been removed.
Finally in post #93 (see pic) most of the components have been removed...
Sorry but I'm a little bit confused...
Fukinagashi
I believe what they mean when they say you don't need C20 C21, it's assuming you have short travel between your source and the amp where there isn't much noise being picked up.
However, the issue is.. Many times, either the SOURCE has some noise, or the length of wire isn't optimal, this is where the 2.2uf Caps will come in handy, and from my experiments "perhaps, also keep the opamps", as I've found that opamps smooths out the sound of poor sources like my iphone.
Edit:
When i say keep the opamps, i mean keep opamps in the loop, I DON'T mean keep the ORIGINAL Opamps which sound like total crap
Last edited:
C20 and C21 are on the output of the schematic in post #1, before the TA2020 (connected to the right most wire and not shown).
In post #7, they are there, you can barely see one of them. They are now film caps, not big electrolytics, as I posted in post #3. In the photo in post #93, they are the big white caps, no longer on the board. Post #93 is just for illustration purposed.
Last edited:
No. C20 and C21 have nothing to do with noise. They are to block DC from the source. If you don't know for absolute sure that your source has no DC, you MUST have capacitors there. Otherwise you risk both the amp and your speakers.
Would you really plug in something that has DC?
Which piece of audio equipment doesn't have decoupling caps at the output stage??
well i just ordered one from ebay for my office.
I am going to make a stand for my LCD monitor that will house 2 6"x4" car audio speakers on each side and the lepai in the middle. i will power it from a spare PC ATX power supply so i can use the 12V to power the Lepai and the 5 volt will power some dummy USB ports to charge my phones.Source will be my phone or my laptop 3.5mm output jacks.
Do the new boards need modding for reliability?
Do you have to remove the zener?
i am assuming i wont need to fit a bigger Power cap as the PC atx power supply should have more than enough capacity?
I am going to make a stand for my LCD monitor that will house 2 6"x4" car audio speakers on each side and the lepai in the middle. i will power it from a spare PC ATX power supply so i can use the 12V to power the Lepai and the 5 volt will power some dummy USB ports to charge my phones.Source will be my phone or my laptop 3.5mm output jacks.
Do the new boards need modding for reliability?
Do you have to remove the zener?
i am assuming i wont need to fit a bigger Power cap as the PC atx power supply should have more than enough capacity?
I've recently tried to use my tube pre-amp with the Lepai and results are very promising: the Lepai itself is not same level if used with a good pre.
Now I'm planning to use it as a final stage.
In the pre output stage (in series with the signal) I have a couple of big paper-in-oil 2uF capacitor. Could I use them instead of C20 and C21?
Last edited:
The only reliability issue I've seen is that pulling the speaker leads out while playing music (or just powered on?) will kill the chip. I'm not sure what could be done to prevent that.
I didn't remove any diodes at all from the board. Are you referring to the one between fault and reset?
As for the big power cap, I would suggest at least 2200uF if you are playing full range. Even though the power supply is more than capable, you also have wiring between, and capacitance closer to the chip is good.
Absolutely! As some of the photos on the wiki show, you can wire it straight into the pads of C20, C21 (after removing them from the board), with the other side going to the pre-amp.
Main input cap
4700uf
Opamp
lm4562
Larger 5amp 12v
These 3 mods I put in made the biggest difference..
the amp doesn't flicker at high volume anymore
the bass is more responsive
less clipping at higher volumes
I did not hear much of any change when I put in another $40 worth of wimas and nichicons.. most of which I had left around after modding my x-fi
I am considering swapping out the potentiometer because my right channel is slightly louder than the left channel, I'm wondering if the pot is the cause,, or maybe the "gain" resistors arn't working right.. or the traces were layed improperly and grounding somewhere.
4700uf
Opamp
lm4562
Larger 5amp 12v
These 3 mods I put in made the biggest difference..
the amp doesn't flicker at high volume anymore
the bass is more responsive
less clipping at higher volumes
I did not hear much of any change when I put in another $40 worth of wimas and nichicons.. most of which I had left around after modding my x-fi
I am considering swapping out the potentiometer because my right channel is slightly louder than the left channel, I'm wondering if the pot is the cause,, or maybe the "gain" resistors arn't working right.. or the traces were layed improperly and grounding somewhere.
Last edited:
$40 for caps?!?!
I spent about $12 and that's because shipping is $5 min. at mouser + $5 for cheap eBay inductors. I think my amp sounds pretty good and I had fun messing with it.
I make no claims of audiophile ears tho.
I spent about $12 and that's because shipping is $5 min. at mouser + $5 for cheap eBay inductors. I think my amp sounds pretty good and I had fun messing with it.
I make no claims of audiophile ears tho.
Main input cap
4700uf
Opamp
lm4562
Larger 5amp 12v
These 3 mods I put in made the biggest difference..
the amp doesn't flicker at high volume anymore
the bass is more responsive
less clipping at higher volumes
I did not hear much of any change when I put in another $40 worth of wimas and nichicons.. most of which I had left around after modding my x-fi
Yea.. I'm all all shop o' holic when it comes to caps
I was like... ooooo... RED..... damn gold is a nice color.. oh man.. black letters on gold... NICE.....
Right now, I'm waiting for virpz's "definitive" mod post where he said he'll post how to make the "button" work exactly as it should...
I'm still on the fence about removing my opamps... going back and forth between my lepai #1 with opamps, and lepai #2 without opamps.
Last edited:
Haha. Nice.
I couldn't get myself to buy those cool looking Wimas...
I couldn't get myself to buy those cool looking Wimas...
Yea.. I'm all all shop o' holic when it comes to caps
I was like... ooooo... RED..... damn gold is a nice color.. oh man.. black letters on gold... NICE.....
Haha. Nice.
I couldn't get myself to buy those cool looking Wimas...
well if you do decide to get them.. Be prepared to have them "NOT fit" inside the case..
THERE's just NO WAY, unless you're willing to run long wires all over, which I'm against, because the 2020 datasheet specifically said to keep the inductor and output caps with as little run as possible. Thanks for the tip. I think I'm just about done modding these... For now. The girlfriend already threatened to leave. Haha.
well if you do decide to get them.. Be prepared to have them "NOT fit" inside the case..
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.