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-   -   Fuze's diyLOD guide [56K!!!] (http://www.anythingbutipod.com/forum/showthread.php?t=39842)

ClieOS 02-07-2009 03:39 AM

Fuze's diyLOD guide [56K!!!]
Not sure where this thread belongs, but I guess this is as good as any related sub-forum ;)
There are more technical discussion on Head-fi if you are interested in this topic...

First, I want to credit 14124all @ Sandisk's forum who first described and built fuze's diyLOD (read here) and waino from the same forum who took his time to do the measurement. This guide is merely a more graphical approach to re-describe the same process of building the diyLOD.

Beware: I can't not guarantee you will find the diyLOD to be better sounding. If you do find it to be better sounding, good for you!

To ensure you are getting the best out of the diyLOD, you'll need to update your Fuze firmware to the latest version!!! The latest firmware are 01.01.22 (for hardware rev.1) and 02.01.17 (for hardware rev.2). You can find more detail on how to update your Fuze here. [EDIT] the current firmware has been updated to 0x.02.26.

What you will need:
1 x original sync and charge cable for diyLOD v1.
1 x Fuze's 30 pins connector (from Ridax) for diyLOD v2. You can use this connector for v1 as well but please pay attention to pins' orientation.
1 x mini plug
1 x soldering iron, small tip (and some solder of course)
1 x Multimeter
1 x Super glue (diyLOD v2)
2 x Capacitors (diyLOD v2, please read v2 guide for choosing the right caps))
Optional: cables (depends on how fancy you want it to be), Ridax strain relief (diyLOD v2)

What you don't need:
Cheap replacement cable from eBay - most of them only have the first 6 pins needed for sync and charge. You will not be able to modify it since pin #7, 22, 27, and 28 are not there. You can, however, use it as you sync and charge cable after you modified the original cable (if you are not using Ridax's connector).
As always, this is a Do-It-At-Your-Own-Risk modification.

*Not sure which version of diyLOD you should use? In short, use diyLOD v1 if your amp has input DC filters (i.e. capacitive coupling / AC coupling). Use diyLOD v2 if your amp doesn't have them (or when you can't be sure). See the 2nd to last section on post #2 for more detail.

[diyLOD v1]
- original sync and charge cable mod

1. Taking apart the connector.
The connector is held together mainly by two hooks at the cable end of the connector (where the two holes on each side are). Those hooks shaped differently which make them a lot more difficult to take apart.

I use the small flathead screwdriver for repairing watches to pry open the bottom side of the connector - first I force the screwdriver underneath where the strain relief goes into the connector, than I pry on each side (black arrow) till it is loose - be careful on this part as you don't want to destroy the housing before you even began the mod.

Red circles mark the hooks and green arrow is where the screwdriver goes in / force applied

You can lift this part of the metal shielding once the whole connector is out of the plastic housing. Don't bend the metal too much or it will break.

The complete disassembly of the connector. Note: you are looking at the bottom side of the connector (pin #2, 4, 6, ... , 30)

The bottom, where the USB connections are wired.

The top, same side as the Sandisk logo is.

2. Rewiring.
I de-solder all the USB wires first as I like it that way (except the USB shielding that connect to the connector shielding). There is no reason to pick one color wire over the other for a particular channel - you can pick what ever way you want to solder them, just be sure to remember to solder them in the correct way when you terminate them at the other end with mini jack. It is also a good time to cut the USB cable to your desired length. I left about 4 inches of USB cable attached from the end of connector strain relief - which is about 3 inches left after I put on the mini jack. You might want to leave a bit more depends on your own preference and future usage.

Here is a sum up of what was / is during the rewiring process:

First, you want to jump pin #7 and pin #22. They are located on two different side. I jumped them with the leftover cable on the original USB cable. The reason for jumping the two pins is because it requires a small voltage (1V ~3V) on pin #7 to activate the LO mode, and it just so happens Fuze's pin #22 has 3V supply that can be utilized in this situation. Note that whether other Sandisk player has the same 3V on pin #22 is yet to know. Until we do know about it, you shouldn't use the diyLOD on any other Sandisk player besides Fuze.

Pin #7:

Pin #22: (I marked #10 and #20 red for better recognition)

Once you jump the pins, should check both the connection b/w the pins with multimeter, as well as the neighboring pins (i.e. pin #5 and #9, #20 and #24) to make sure nothing short! Measure every time you finish soldering a pin!!!

A quick test: To see whether you can activate LO at time point, start playing a songs on Fuze and listen to it, than insert the jumped connector in and you will notice the music is silenced (on headphone) but continue to play on the player. You will also notice the scroll wheel no longer able to control the volume. Remove the connector and everything should go back to normal. Note: Your Fuze must be in the latest firmware to perform this test.

I pick red cable as my right channel, black as my left channel, as green as my audio ground. Note that you should also be able to use Pin #3 and 6 (USB ground) as your audio ground as well. Note: be careful on the cable length b/w the strain relief and the pins - you don't want it to come short when you try to put them back together. If you are not sure, extend the cable by wiring an extra length of wire and insulate it properly (you don't want them to short either!)


Since I didn't use the USB shielding for anything, I insulated it as well.

3. Reassembly
Remember to put some tape over the PCB to avoid short circuit,
Terminate the other end with a mini jack and voila, you have yourself a diyLOD!


Fuze - diyLOD - FiiO E5 - Head-Direct RE0

Fuze - diyLOD - iBasso T4 - Head-Direct RE0

Continue to next post...

marksj 02-08-2009 02:32 PM

What can I say but GREAT JOB!!!!!!!!!!!!

ClieOS 02-14-2009 09:21 PM

[diyLOD v2]
- Ridax connector with caps

1. Taking apart the connector.
Ridax connector are pretty easy to take apart. Beside the connector and its half metal shield, there are also two small pieces of plastic that are going to be the push buttons of the release mechanism.

An unopened Ridax connector next to Sandisk connector, plus another being disassembled.

Here is a closer look at the pins and its half metal shielding.

Optional: Ridax strain relief
As you can see, Ridax strain relief is actually thicker than the connector housing, you will have to trim it down yourself.

Here is how I trim mine. Make sure you don't over trim yours. BTW. The strain relief only allow cable diameter about 5mm or less to pass. If you are using thick custom cable, you don't need to get this.

2. Wiring.
You can use any cable you find fit. I just use the leftover USB cable of diyLOD v1 mod. Most of the process is identical to diyLOD v1, so read the previous post first.

Here is a sum up of what was / is during the rewiring process:
[IMPORTANT] Notice that the pins on Ridax connector is upside down in compare to the Sandisk connector, so don't mix up!

First, jump pin #7 and #22.

A quick test: To see whether you can activate LO at time point, start playing a songs on Fuze and listen to it, than insert the jumped connector in and you will notice the music is silenced (on headphone) but continue to play on the player. You will also notice the scroll wheel no longer able to control the volume. Remove the connector and everything should go back to normal. Note: Your Fuze must be in the latest firmware to perform this test.

I use a 5 inches pieces of the leftover USB cable as my main cable. I clean up one end and set it up for soldering (like diyLOD v1, red for right channel, black for left, green for ground, and USB shield to connector shield), than I insert the previously prepared strain relief up to that end. To make sure the strain relief will stay in place and does its job, I put a bit of super glue to glue the cable and the strain relief together (see picture). Be sure that the glue is set firmly before you use the cable. On the connector plug, I extend pin #27 (LO right) and #28 (LO left) with two pieces of cable, about one inch should be enough.

Now we can prepare the caps. I use Panasonic audio caps, 220μF, 6.3V. The choice of caps is made because on the similar spec of caps is used in Griffin dock. I strongly advice the use of non-polarized / bi-polar caps (they are more suitable for the purpose). Also, I will advice you to read Tangents' Input Capacitors for Headphone Amps and dsavitsk's Some Notes on Coupling Capacitors articles regarding caps' function and option. The circuit in Griffin dock is a bit more complex (a typical capacitor coupling design). Here is what in Griffin dock (confirmed by 14124all, thanks)

Here is my adaptation:
Note, bi-polar caps are strongly recommended.

First, I punch four small hole on the upper housing with hot needle so the caps can go through. There is not enough space inside the housing for those caps so they have to be place outside. You can place the caps (in series) in any place b/w the amp and the dock, I just choose to do it this way cause I think it is more elegant this way ;)

Note how I bend the legs inside the housing to make sure the caps stay in one place. Apply a tiny bit of super glue on both side to secure the caps' position.

Now the actually wiring following the decouple diagram above. Not an easy job, I can tell you this much (especially in such tight space). Both pin #27 and #28 are coupled to the positive end of one of the caps.

Now you can terminate the other end of the cable with mini jack and test it out before you put everything together.

3. Finish Up
Again, remember to put some tape inside to avoid short circuit. make sure the insulation is perfect!

diyLOD v1, v2, and an empty Ridax connector.


Fuze - diyLOD v2 - 3MOVE

diyLOD v1 vs. v2 - The Difference
So what is the big deal about coupling / decoupling caps that I'll want to make a second LOD just to put two in? The main reason behind diyLOD v2 is to make sure the LO functions as intended. For both the circuit of Griffin dock and AS3525's datasheet, I find out that caps are indeed part of the original design (as DC filter). So what is the main difference b/w v1 (w/o caps) and v2 (w/ caps) beside how caps affect SQ? The differences lie in noise feedback and DC offset problem. First, with out the caps, sometime you can hear distortion caused by turning the potentiometer (volume pot) on the amp. With the caps, it is all silence. Second, There is a ~1.4V DC offset on the line-out signal. When you set the volume too high on some amp (way beyond safe listening volume), you will notice the volume starts to drop out as the volume is going up. I suspect that is DC/AC issue there since not all amp have input filter to deal with DC offset. The 'evil' about DC offset is, amp with no DC filter will amp the DC voltage (along with the music, which is an AC component) and cause it to become too high. The high voltage can kill your headphone transducer, depends on how high the voltage is and how sensitive the transducer to the voltage. Note, some amp do have DC filter as part of the design (i.e. cmoy, Practical Devices' XM3, etc) and there is no need to add more caps in the LOD.

In technical standpoint, I think diyLOD v2 is probably more 'correct' (or 'safer', if you like).

ClieOS 02-20-2009 09:57 AM

Here is the diyLOD v2i. Same dock, different caps placement.


dfkt 02-20-2009 10:12 AM

That looks absolutely stunning, ClieOS!

I wish Cowon players had a proper line out... :/

ClieOS 02-21-2009 03:47 AM

Thanks, dfkt. I would have bought a D2 if I can find it in stock locally. Than again, I am quite satisfied with Fuze's SQ :D

Sansasensei 03-09-2009 01:17 AM

Whipped up an LOD this evening using a Sansa plug and a Sony cable/molded plug.... works great! A terrific increase in sq. Thanks, ClieOS!! Terrific work and a very easy to follow tutorial. Now if there's a tutorial out there for steadying hands while soldering... :)

HulkSmashNow 03-24-2009 01:09 PM

Just saw this one on eBay:

Sansa Fuze Line Out Dock Cable For Headphone Amp - eBay (item 290303555722 end time Mar-27-09 09:29:44 PDT)


jadorm 04-13-2009 04:42 AM


ClieOS 04-13-2009 05:27 AM


Originally Posted by jadorm (Post 346629)

You should really try ALO sometime :rolleyes:

jadorm 04-13-2009 09:46 AM

I probably should build 1 myself before saying that guy is overpriced but, I really think any cable that costs 40$ is overpriced even if it is handmade. I probably will be building one for the car in the future. and maybe then I'll have a different take. btw, nice blog I don't have IEMs yet but I'm lookin.

ClieOS 04-13-2009 10:21 AM

Just to clarify, I am the guy (who makes the eBay LOD, hence why I didn't commend on HulkSmashNow's post). The reason for the price is mainly because I have to order parts from U.S. (Mouser) and ship them to my hometown (which is on the opposite side of the world), and you will be surpriced how expensive shipping can get (caps are $.25 each in U.S. but >$3 each when they reached my house). Those LOD I sold on eBay is just a way for me to collect back some of the money spent (on experimenting with different parts during the process of writing this guide), and also to use out all the left over parts I don't need anymore. If you are in the U.S., you can easily make one with $10 or less, but it will be twice / three times as expensive for me to build one with just the parts along (not including the time and work it'll take). I am mainly want to be clear that I am not really making a lot of money out of this and it is really unsustainable for me. In any case, I am happy that I have used up all the parts and gain back some of the money in the end, thus I have no plan to make any more of them.

Do check on the Head-fi thread (link on first post, 2nd line), there are a few other who posted their version over there as well.

jadorm 04-13-2009 10:27 AM

I figured it was someone getting stuff straight from china and just ripping off a design they found on the internet.....which happens on ebay, sorry if I offended.

ClieOS 04-13-2009 10:34 AM


Originally Posted by jadorm (Post 346667)
...sorry if I offended.

None taken ;)

Mattman243 06-18-2009 11:15 AM

Is there any way to make one of these for an e200 series player? It looks like the same plug, but I'm sure the internals are different.

ClieOS 06-19-2009 09:54 AM

IIRC, someone tried on E200 V2 and it works - but not on V1, probably because V2 series uses the same SoC as Fuze.

pitsel 08-05-2009 12:10 AM

good job => Great

berre 12-01-2009 06:37 AM


Some extra questions from a noob, sorry if this is common knowledge or discussed somewhere else

- is the volume louder compared to just crancking up the volume on the headphone output when using it on an aux-in?

- which version (v1 or v2) should I make to use with the aux-in of my car's headunit?

- can I add a second cable with a USB connector to the sansa connector so that I can charge it as well via e.g. a USB car charger and if so, which pins should I connect how?


m_k 12-02-2009 04:30 AM

Does anyone know if somebody has noodled out a Line INPUT method for the Sansa 30 pin connector?

I don't know if there are signal lines to support such a function -- but I'd almost be surprised if there were NOT Line Input pins on at least some models. Consider how the video out pins on the View were never really "offically" supported/documented, yet, you can buy a third-party video/audio line-out cable for the View.

I'd also like to know if anyone has figured out the protocols for the control signal handling via the cable port. This is something we DO know for certain to exist, a fact made clear to me the first time I dropped my c200 onto my Timex clock radio and found I could control the Sansa via the Timex IR remote control.

With line inputs and the ability control the device via the cable, it would make these things into VERY useful audio recording devices. Think of the potential -- everything from home-made music demo recordings to podcast production, etc., etc., etc. Plug the audio board (mixer) line-output into the Sansa, rig up a switchbox for record/play/stop/rewind etc., and there ya go.

As it rests now, the only way to do STEREO recording (and, at a reasonable bit rate) is to feed a mixer into an FM modulator, and then record off the air. This is kinda Rube Goldberg, and, loses significant audio quality (versus direct line input signal connection), and, there's potential for everything from RF interference to loss of privacy (your FM modulator will have more range than you think -- someone with a receiver with a hot front end and a good yagi antenna can snoop on you from quite a distance).

If there is NOT physical Line-IN hardware support via the connector, then perhaps someone with the right skill set could figure out how to cheat our way in (cut traces, solder in jumpers, etc.)?

Andreas 12-02-2009 09:23 AM


Originally Posted by berre (Post 419102)

Some extra questions from a noob, sorry if this is common knowledge or discussed somewhere else

- is the volume louder compared to just crancking up the volume on the headphone output when using it on an aux-in?

- which version (v1 or v2) should I make to use with the aux-in of my car's headunit?

- can I add a second cable with a USB connector to the sansa connector so that I can charge it as well via e.g. a USB car charger and if so, which pins should I connect how?


About the same as max headphone out. Point is the signal is clean, though there shouldnt be that much difference.

V1 is a prototype, V2 is the one you want. just read the post, it's all explained

Yes. The pinout is shown in the first post. If you can't find out what to do from the info provided here, you shouldn't attempt this because that means you don't have the DIY knowledge needed to do this safely and might end up wireing 5V to audio. Soldering 30 pin connectors is hard enough to do properly so that if you don't have enough experience/knowledge to know WHAT to do without someone telling you, you definitely do't have enough experience to know HOW to do it.

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