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iBasso D42 "Mamba" with dual dacs! !! Hey Hey! Improved Starting on Page 76 . - Page 58

post #856 of 1153
I've had very good service from iBasso, even on a product they don't officially support: the FiQuest. My case was stripped and they replaced the case for me without telling me they would - it was a surprise, and a damn good one too! I was checking how much it would cost and it arrived with my nice new P3+ (favourite so far).
post #857 of 1153
Sorry for silly question: where can I get the parts for D4 to roll by opamps? Is it plug-and-play or do I need soldering iron and deep knowledge to do it? I'm ready to order D4 and I was thinking if I can order somewhere ready rolled amp?

Johann

Quote:
Originally Posted by supern0va View Post
finally rolled by opamps! now my d4 sounds much warmer!

here's a pic:


thanks to madwolf for his advice, svenmz8 from jaben forums for more advice and help in soldering, and qusp for his detailed pic in d10 thread!

my d4 works slightly differently from larry (headphoneaddict)'s in terms of the connection:

With USB power from my Macbook, i can use:
1. "AUX">>IEMs to bypass the amp, using only the DAC
2. "headphone">>IEMs to use both DAC and AMP
3. "AUX">>LOD>>IPOD and "headphone">>IEM, i can play from the macbook (much softer), or play from my ipod, or both!

All these without a battery!
post #858 of 1153
Quote:
Originally Posted by trentino View Post
I'm so busy enjoying the D4's dac/amp-combo with HD650's I don't have time to surf head fi. Feels good to actually enjoy the gear for a change, head fi usually makes me chase new gear more than enjoying what I have
That sound amazing,the D4 ,the HD 650 don't they need more juice then the D4 could provide.
post #859 of 1153
The D4 is good for 300ohm. As far as my DT880/600ohm is concerned though, forget about it.
post #860 of 1153
Quote:
Originally Posted by dongringo View Post
The D4 is good for 300ohm. As far as my DT880/600ohm is concerned though, forget about it.
yeah, i sort of agree with that. i'd say 250 or 300 ohms is pushing it a bit, though. of course, it depends on the sensitivity as well.

i've heard the 250ohm dt880 through the D4, and it wasn't half bad...

the 600 ohm dt990, however, sounded like an alarm clock radio.
post #861 of 1153
Does anyone have a few extra 2.2k resistors? I'll pay for the stamp, just don't want to buy 200 of them for $10. (TIA)

I thought I noticed a bit of clipping on a few songs, and turned down itunes - that seemed to get rid of it but would rather have full resolution on the dac.

Quote:
Originally Posted by madwolf View Post
Initial Solution, quick remedy, (Have not spend much time thinking of the best solution). I decided the quickest solution to the problem is to reduce the gain of the AD8616. It original gain of the AD8616 is 2, by adding a resistor from the output of the 8616 to the negative input we could adjust the gain.
The original resistor across is 2.2K ohm.



The Gain resistors are located on the top side of the board, and to solder on that you need to remove the Big Nichicon HZ cap (On my case it is Rubycon ZL) to troublesome, to fix this way.

So instead of changing the resistor, I found a compensation capacitor beside the AD8616 which is connected in parallel to the feedback resistor. By adding a 2.2K ohm across this I reduce the gain to about 1.5. From the Picture the 2.2K resistor is sitting on top of the capacitor. label C26 and C28.

You could also solder the resistor directly on PIN 6,7 and PIN 1,2 on the AD8616. (If I do that I would be tempted to change the AD8616! )

I so happened to have a 2.2K 1% SMD 0805 resistor at home. How lucky.
So after adding the resistor I test it again and the Clipping would not occur.
Now I could feed signal at 100% resolution to the D4 instead of just 80%

It should be placebo, on initial testing I could hear more details from the DAC now. Sweet. Well in theory it is 100% now instead of 80%, so might not be placebo.



The power is definitely stronger on the dark side.
post #862 of 1153
Quote:
Originally Posted by stevier5000 View Post
Does anyone have a few extra 2.2k resistors? I'll pay for the stamp, just don't want to buy 200 of them for $10. (TIA)

I thought I noticed a bit of clipping on a few songs, and turned down itunes - that seemed to get rid of it but would rather have full resolution on the dac.
If you would PM me with your address, I will send you a few.
Ron
post #863 of 1153

iBasso has good service

iBasso just got my d4 back for repair they will send it back to me in two or three days i can say i do mis my d4.A great amp and good service. way to go iBasso. now iam a true believer you rock
post #864 of 1153

my D4

iBasso sent my tracking number today they got some dam good service. its on its way home.iBasso is at the top of there game
post #865 of 1153
I ordered my iBasso D4 on 13. and received it today (to Iceland). I'm a little bit sceptic of the concept of burn-in but I decided to let it play for 48 hours before trying it on with my HD-650.
post #866 of 1153
I just ordered my first hp amp ever, the D4, and I'm stoked! Gonna use with my macbook pro and dt770/80. Have always been listening to 128kbs and 160kbs mp3's and I'm now reripping my music library to flac's and mp3 v0's (to find what suits me). Not sure what kind of "sound" experience lays ahead of me. Pretty excited :-)
post #867 of 1153
I found a good test to demonstrate the clipping on the ibasso d4 DAC section - play Radiohead, In Rainbows, 15 Step, right about 2:30 - 2:36, there's a quick kick drum section. When i have the itunes volume turned up to 100%, there's definite clipping/artifacts. If I turn it down to ~70%, and turn the volume control on the ibasso up, voila, no clipping.

Anybody else have this song and amp, care to test? I'm planning on soldering on the two 2.2k resistors tonight, will re-listen and update.
post #868 of 1153
I did the fix and I no longer hear clipping, haven't had too much time to evaluate but I like what I hear. This was my first experience soldering SMD's, it was pretty easy - at least after watching a couple how-to videos on youtube. I did spend a good bit of time practicing on some old computer hardware though.


Quote:
Originally Posted by stevier5000 View Post
I found a good test to demonstrate the clipping on the ibasso d4 DAC section - play Radiohead, In Rainbows, 15 Step, right about 2:30 - 2:36, there's a quick kick drum section. When i have the itunes volume turned up to 100%, there's definite clipping/artifacts. If I turn it down to ~70%, and turn the volume control on the ibasso up, voila, no clipping.

Anybody else have this song and amp, care to test? I'm planning on soldering on the two 2.2k resistors tonight, will re-listen and update.
post #869 of 1153
Quote:
Originally Posted by TheWuss View Post
yeah, i sort of agree with that. i'd say 250 or 300 ohms is pushing it a bit, though. of course, it depends on the sensitivity as well.

i've heard the 250ohm dt880 through the D4, and it wasn't half bad...

the 600 ohm dt990, however, sounded like an alarm clock radio.
I think we all have different thresholds for pain/pleasure. The DT880 600Ω sound great with the D4 for me. There are some older songs which are a bit too quiet, but they sound amazing still. If it sounds like an alarm clock radio, something must be wrong with the connection as the sound is as good as anything I've heard at that volume, if flat and neutral in comparison to some hot/warm tube and mains amps I've used with them.
post #870 of 1153
Quote:
Originally Posted by shigzeo View Post
I think we all have different thresholds for pain/pleasure. The DT880 600Ω sound great with the D4 for me. There are some older songs which are a bit too quiet, but they sound amazing still. If it sounds like an alarm clock radio, something must be wrong with the connection as the sound is as good as anything I've heard at that volume, if flat and neutral in comparison to some hot/warm tube and mains amps I've used with them.
I would want to know about what you feel about its DAC only section, what does it compare to.
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