[t0wer]

Quote:

After just a brief audition of the stock opamps, of course I just had to roll to the D4 Topkit!

I don't know what opamps

 

[kunalraiker]

There is a topkit, check with HiFlight for the opamps.

 

[brendon]

Please delete

 

[dj nellie]

I just got my Mamba last night, and have been listening to it for a few hours. Thanks to all the Head-fiers who have given their impressions and recommendations, I'm very happy so far.

I just started browsing Head-Fi when I was looking for a high-quality IEM, and I have to say that this site is a slippery slope, a never-ending cash suck. But I'm loving the journey.

I started with Shure SE530s, then sold them for Westone 3s, and then added AT-AD700s and Triple.Fis. I was happy with the sound of my W3s, but they're too loud with my iPod Touch and Cowon S9 in quiet environments unless I use the stock volume control, which seems to muffle and darken the sound. So I was originally going to get a small, portable amp that would basically function as a high-quality volume attenuator. I thought about the T3 but had a little extra cash, so I figured why not take a step up to the D4?

When I saw the tiny little thing in its box, I knew I had made the right decision. The D4 is surprisingly light and portable--it's hard to tell just how small it is from iBasso's pics, but it really is close to the size of a pack of cigarettes.

As for sound quality as an amp, the D4 appears to provide more improvements to my AD700s than my IEMs, but the gains are noticeable with every phone I try. The sound is just cleaner, and I'm hearing micro-details in the background of songs that I never noticed. The soundstage is wider both horizontally and vertically; on Spank Rock's "Sweet Talk", I actually had to look over my shoulder because I thought that the background yelling and talking in the song was happening behind me. The bass on my W3 is slightly reigned in and tightened, and perhaps partly because of this, the mids (especially vocals) seem richer and more forward. When songs that I was tired of and used to skip on my iPod come up, I feel compelled to listen to them and find myself enjoying them again.

I do notice that the sound improvement is much more noticeable out of my iPod's LOD than when I amp the headphone out of my Cowon S9. I can't really tell yet what, if any, improvement I'm getting by amping my S9's headphone out--the sound seems much darker than my iPod.

One last thing I've noticed: The D4 really wasn't designed for sensitive IEMs. I'm having a somewhat hard time finding the right volume for my W3; even on the lower gain setting, the slightest turn of the volume knob will take the sound from way too quiet to way too loud (at least in quiet room).

I'm using iBasso's 3.5-3.5 interconnect and LOD, which seem decent but I'm sure aren't near top quality. Can anyone comment on the quality of these cables, and how much of an improvement I'd get with a better cable and LOD?

 

[trentino]

Great read and interesting impressions dj nellie! I'm getting ready to order the D4, although my 530's (I think) are even more sensitive than your W3's? Well, I plan on using the D4 for bigger head phones as well in the future, hopefully the D4 is good for almost all type of head phones. At least that's what I've read.
Thanks for the read!

 

[dj nellie]

I believe the SE530 is pretty close to the W3 in terms of sensitivity, so you'd have the same issues I do. It's not a big deal, you just have to be patient fine-tuning the knob (which you may have to do often if you're listening on shuffle and your songs' volumes aren't normalized). And like you said, we'd all like to step up to some nice full-size cans down the road.

I had been hearing a few pops while listening to my iPod, and I started to freak out...until I realized my Blackberry was a few inches away from my D4. I put the phone away, and the pops seem to have gone away. Yes, I'm a noob.

 

[ovrclkd]

Does anyone know if you can power the mamba thru a 12v vehicle power point with a usb adapter?

 

[HiFlight]

No, it will not work. I tried your suggestion using my USB 12v adapter, and while the amp powered on, the Aux input is disabled by the USB connection which takes priority and switches the Aux input to the DAC output.

 

[lwells]

Quote:

Originally Posted by ovrclkd /img/forum/go_quote.gif Does anyone know if you can power the mamba thru a 12v vehicle power point with a usb adapter?

How about 9v power inverter --> wall wart USB --> USB cable ?

 

[HeadphoneAddict]

Quote:

Originally Posted by lwells /img/forum/go_quote.gif How about 9v power inverter --> wall wart USB --> USB cable ?

nope.

You'd need to make a dummy 9v cell with wires coming out the bottom to connect to a 12v>9v adapter in the car, and then stick it in the amp and screw down the rear battery cover around the wires coming out. How about a few rechargable 9v cells instead?

And, to OVRCLKD, if I'm gonna take the time to answer any of your questions in PM, it would have been nice to know I could have answered in this thread instead. Next time, point someone to the thread and ask if they can chime in so we don't have to do it twice.

 

[madwolf]

Before

After

I have completed D4 Modding sometime back, finally I have some time to write this
(it so happend I wrote this at about some 25,000ft above sea level).
It does seem that most of the modders are busy with the Fi.Q very lonely here.

The changes started off as a Dream of using the D4 at 9V or 12V which proved to sound
much better than 5V especially for bigger headphone and definately HD600.
At 12V it drives HD600 comfortabily close to a desktop amp.

The DC to DC converter consists of a filtering circuit before going into the upconverter.
A regulator to regulate the voltage to 12V and a enhanced Pie Filter.

When I was taping the 5V from the D4 I noted 2 nos of zero ohm resistor at position L1 and L2
I think the designer at ibasso have in mind 2 little ferrite beads or some small inductor
but at a later time decided not to install it. I took out the 2 zero ohm resistor and replace it with
2 small inductors. This would help to reduce ripples at the power lines. There are 2 different
power regulator, one for the AMP (L/R and BUF), and another for the DAC + 8616.

The AMP reservoir choosen by iBasso was a 10V 2200uF Nichicon HZ series Capacitor, This is a very good
choice by iBasso, Given a choice I would not have change this but the rating of 10V was insufficient
and I was force to change it to a 16V part. I choosen a Rubycon ZL series.

The DAC Capacitor needed to be change the 100uf Nichicon Fine gold would not cut it here, I replaced
with a Sanyo WG series 1800uf. The reservoir for 8616 was likewise replace with OSCON with
WIMA bypass.

When I solder the DC converter to D4, I prefered to remove the battery connector, with
that removed I have additional space to put in another reservoir for the AMP. A similar RubyCOn ZL.
A diode D1 was removed as it was no longer needed. D1 is to prevent a a short if the battery is
inserted with the wrong way. Since there would not be a bettery here, there isn't a chance of that happening.
By removing that I have an additional 0.4V.

Buffer used here are BUF634. They proven to be a favourate and is notably better for big cans.

L/R Just when I was about to settled with 797ANZ, someone in the forum bite the bullet with 797BNZ,
Hopefully he does not posion the owner of the D4, means more work for me.

Additional mod possible is to remove the relay, It is not needed as the owner is mainly using
this from powerbook.

Do you think I have void the warrenty of this D4 ?

 

[LionPlushie]

Grats! Now you have void the warranty of D4, but i bet the change in sound is worth it?

EDIT: noticed that you're from singapore. can i try your D4?

 

[madwolf]

Can but I would be sending it off very soon so you have to be fast. Let me poison you.

 

[supern0va]

Madwolf, congrats on ur completed mod. It sure sounds good with the um3x... im sure it sounds even better with full headphones (which unfortunately we didn't get a chance to try)

I'd like to harp on my earlier pt abt having a recharable battery powering @ least 5V (which should serve most of my purpose as I use IEMs). Referring to my earlier post, any comments? The batts that I mentioned should fit with space to spare.

Quote:

Originally Posted by supern0va /img/forum/go_quote.gif Quote: Originally Posted by HiFlight /img/forum/go_quote.gif Quote: Originally Posted by supern0va /img/forum/go_quote.gif Not sure if this makes sense, but what I had in mind was 2 batteries connected in series. So voltage will increase (i.e. 3.7V x 2), amperage will not change as there are 2 batteries (not sure abt this). One possibility is this battery: iPod Video 30/60gb Battery This is a iPod Video 30/60gb Battery. Its dimensions are 45 x 19 x 4mm, so 2 of them will still take much less space than a 9V battery (dimensions are 48.5 x 26.5 x 17.5 mm). Amperage sounds good.. 480mAh 3.7V. I suspect that the newer gen nanos and shuffle will have even smaller batteries. It would likely work, but what method will you use to recharge them? The D4 contains no recharging circuitry, nor will the USB recharge them. Sorry I'm not really good with circuitry (limited electronics engr knowledge!), but could we not, in theory, have a small recharging circuit connected to the USB? then the USB would be able to recharge the batts. There should be some remaining space based on the size of the batts and the size of the space inside the D4. Not sure if there's a need for some kind of auto-disconnect function to prevent overcharge.

 

[LionPlushie]

Quote:

Originally Posted by madwolf /img/forum/go_quote.gif Can but I would be sending it off very soon so you have to be fast. Let me poison you.

sending it to where?

@supern0va
you from Singapore?