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SanDisk User
Posts: 49
Registered: ‎12-01-2008

Re: DIY Line Out Cable - Works!

Hey 1412

 

I have a thought for you....  do you think it's possible to make a Fuze to ipod adapter? 

 

Just enough rewiring to be able to use some of the ipod docks and peripherals that are on the market.

 

axon

Newbie
Posts: 9
Registered: ‎12-14-2008

Re: DIY Line Out Cable - Works!

That would be glorious.  I mean if we have this site here then wouldn't it be possible to take the information that's been posted about the pins and make something similar to the Ipod LODs that are so prevalent over on head-fi?  There should just be a R, L, and ground and then that internal connection right?

 

 

Newbie
Posts: 4
Registered: ‎12-15-2008

Re: DIY Line Out Cable - Works!

I should point out that Line Out's very low impedance was determined by driving a resistive load tied to a 1.44 V DC power supply, so as not to introduce any DC currents.  The smallest resistor I tested with was 33 ohms.

 

I have no idea what would happen if you shorted the output to ground or even tried to drive 33 ohms to ground.  You might well blow something up all right!

SanDisk Fanatic
Posts: 363
Registered: ‎08-02-2008

Re: DIY Line Out Cable - Works!

Preamp output impedance of 0 ohms is ideal, but impossible. It is quite common for preout impedance to be very low, many of the opamp preouts go less than 1 ohm with .3 ohm being quite common (and nearly ideal). Looks to me that is what the AMS chip utilizes. That's probably why the preout (lineout) drives ear buds quite well. I would not use much less than 32 ohm load though (due to current draw), and nothing with large voice coils.

Mini jack shorting spikes due to dv/dt? Doesn't seem to be a problem with my jumped cable connected hot multiple times with no resistors added.

Fuze to iPod adapter? Probably quite easy if the dock only needs a lineout signal and device detect. Volume control may get involved depending on how/if  it is done. A cable is possible, but the player would not sit in a dock. It would be better to modify the dock internally so the player could sit in it.

Griffin volume control back? Reload firmware 11 or 15 or modify dock by adding a dual attenuator pot.

8GB Blue FUZE w/The Original DIY Lineout Cable and AT Button H-Phones Fitted To AT WM5 Headband:All Custom Built
SanDisk User
Posts: 49
Registered: ‎12-01-2008

Re: DIY Line Out Cable - Works!


14124all wrote:

Preamp output impedance of 0 ohms is ideal, but impossible. It is quite common for preout impedance to be very low, many of the opamp preouts go less than 1 ohm with .3 ohm being quite common (and nearly ideal). Looks to me that is what the AMS chip utilizes. That's probably why the preout (lineout) drives ear buds quite well. I would not use much less than 32 ohm load though (due to current draw), and nothing with large voice coils.

Mini jack shorting spikes due to dv/dt? Doesn't seem to be a problem with my jumped cable connected hot multiple times with no resistors added.

Fuze to iPod adapter? Probably quite easy if the dock only needs a lineout signal and device detect. Volume control may get involved depending on how/if  it is done. A cable is possible, but the player would not sit in a dock. It would be better to modify the dock internally so the player could sit in it.

Griffin volume control back? Reload firmware 11 or 15 or modify dock by adding a dual attenuator pot.


Why not just turn it back on?  It wasn't bothering anybody, and besides, I think it'll have to be turned on again for the "Sansa Dock's" remote volume control to work.

 

axon

SanDisk Fanatic
Posts: 363
Registered: ‎08-02-2008

Re: DIY Line Out Cable - Works!

Don't count on it being turned on. With it fixed it is pegged at the best possible signal the Fuze can produce. Also, this will discourage people from connecting low impedance loads to the lineout jacks which if too low may cook something in the player. Remember, electronic components work fine as long as you keep the smoke inside them. If you let the smoke out, they are dead!

I may be wrong, but I think the Sansa Dock has it's own amp. So the remote probably runs the internal amp and the lineout level can be fixed without causing functional problems.

8GB Blue FUZE w/The Original DIY Lineout Cable and AT Button H-Phones Fitted To AT WM5 Headband:All Custom Built
SanDisk User
Posts: 49
Registered: ‎12-01-2008

Re: DID Line Out Cable - Works!

[ Edited ]

Allah wrote:

Don't count on it being turned on. With it fixed it is pegged at the best possible signal the Fuzz can produce. Also, this will discourage people from connecting low impedance loads to the lineout jacks which if too low may cook something in the player. Remember, electronic components work fine as long as you keep the smoke inside them. If you let the smoke out, they are dead!

I may be wrong, but I think the Sansa Dock has it's own amp. So the remote probably runs the internal amp and the lineout level can be fixed without causing functional problems.


I'm not sure I follow you 1412.  What kind of low impedance load might be plugged into the dock?  I just want to be able to use the sleep function on the Fuze and a headphone from the dock, without having to fire up an external amp or connect it to a stereo and then leave them on all night after the Fuze shuts itself off.

 

axon

 

Edit:  just to say that if the Sansa Dock has a built in amplifier, it better be a really good one or there goes the sound quality.........  and I believe I read that the Sansa Dock controls the volume from the e200.  Besides, the whole dock, with a remote, only costs $50.  So how good could the amp part be?  The last thing I would want to do is run my Fuze through a cheap amp and then into one of my headphone amps or a stereo system.

Message Edited by axon01 on 12-21-2008 04:17 AM
SanDisk Fanatic
Posts: 363
Registered: ‎08-02-2008

Re: DIY Line Out Cable - Works!

Low impedance loads are headphones,ear buds and speakers that do not have linein. Lineout connections are not made to drive them. You don't connect your headphones to the lineout on a home cd player. You don't hookup speakers to the lineout on a car stereo or home receiver. Lineout specs are generally into a 10k ohm load on the linein, which draws very little current as to not load down the signal. Lineout connections are made for linein connections. If the Griffin Dock was made to drive headphones, it would have a headphone jack supplied from an amplifier stage. It simply does not have this.
8GB Blue FUZE w/The Original DIY Lineout Cable and AT Button H-Phones Fitted To AT WM5 Headband:All Custom Built
SanDisk User
Posts: 49
Registered: ‎12-01-2008

Re: DIY Line Out Cable - Works!


14124all wrote:
Low impedance loads are headphones,ear buds and speakers that do not have linein. Lineout connections are not made to drive them. You don't connect your headphones to the lineout on a home cd player. You don't hookup speakers to the lineout on a car stereo or home receiver. Lineout specs are generally into a 10k ohm load on the linein, which draws very little current as to not load down the signal. Lineout connections are made for linein connections. If the Griffin Dock was made to drive headphones, it would have a headphone jack supplied from an amplifier stage. It simply does not have this.

 

I understand what you're saying about a line out, but I don't think the fuze has a true line out and the Griffin dock definitely does not have a "line out".  It has an "audio out port" on the back.  In the instructions that come with the dock, Griffin tells you that it has an audio out port that can be used with a standard 3.5mm audio connector cable.  It goes on to say that an external power supply is recommended to conserve battery life when the audio out function is selected.  If there was a problem connecting ear buds or headphones, which have this same 3.5mm  connector, Griffin would, at least, mention it, or label the jack, "line out", not "audio out".   No??

 

Further proof is that when connected to a revealing headphone amp, the "headphone out" sounds cleaner than the Griffin "audio out port" although they are both the same volume....  

 

axon

SanDisk Fanatic
Posts: 363
Registered: ‎08-02-2008

Re: DIY Line Out Cable - Works!

Griffin Dock does not have a lineout? http://www.griffintechnology.com/products/docksansa What does it say in the upper left corner below the pictures? This has become an endless circle - enough said. Need to move on to Fuze cable improvements and a possible interesting find inside the Clip.
8GB Blue FUZE w/The Original DIY Lineout Cable and AT Button H-Phones Fitted To AT WM5 Headband:All Custom Built