[Jimmyblues1959]

Related to my post above. Can anyone explain what the point of the stock T60rp cable is? why does it have a 4 pole connection on one end, and a three pole connection on the other. The female jack on the headphones can take a balanced 3.5mm input, why isn't it just 3 pole on each end? Thanks

I think it has to do with the fact that instead of having a separate right and left cable for each channel of the headphone,
the T60 only has a single input for both right and left channels on the left side of the headphone for balanced performance;
hence the three black bands instead of two.

For example with the T50RP which is not balanced, there are only 2 black bands on the input jack for the headphone cable.

 

[freemental]

Hi. I am in the same position as you but very confused.

I am finding it almost impossible to get a 4.4mm balanced jack for my headphone amplifier, to go into a 3.5mm balanced jack to go into my T60RP argon.

I bought a cheapo cable from aliexpress which was meant to be for a DAP, that should have worked - it has 5 poles on the 4.4mm end, and 4 poles on the 3.5mm end. But it doesn't work When I push the 3.5mm end into my T60rp, it actually sends both left and right channels to both drivers - so on a stereo test for right, it comes out of both drivers, and on a stereo test for left it comes out of both. When I try that cable on another unbalanced set of cans like the SHP9500, the left channel comes out correctly, but the right stereo sound comes out of both.

I think the cable is junk.

The T60rp works fine with a unbalanced 3.5mm to 3.5mm stereo jack though.

Can you describe how you made your cable please in more detail?
Thanks!

You need to look for a cable specifically for Fostex t60rp headphones, because different headphones may have different cable pinouts. I can advise you to cut off the 3.5 connector in your defective cable and solder a new one in accordance with the Fostex pinout (in the messages above I attached a diagram of the correct pinout).

 

[freemental]

Related to my post above. Can anyone explain what the point of the stock T60rp cable is? why does it have a 4 pole connection on one end, and a three pole connection on the other. The female jack on the headphones can take a balanced 3.5mm input, why isn't it just 3 pole on each end? Thanks

4-pole connector, because a balanced connection requires 2 contacts (positive and negative contact for each channel) and 3 contacts for an unbalanced connection, because 2 negative contacts are combined into one contact - a common ground

 

[Longfellow78]

4-pole connector, because a balanced connection requires 2 contacts (positive and negative contact for each channel) and 3 contacts for an unbalanced connection, because 2 negative contacts are combined into one contact - a common ground

Thanks @freemental but I still don't get it. Are you saying that you can use the stock Fostex cable to do balanced? If so, why do you need a different cable? If not, what is the point of it being "balanced on one end, and regular stereo on the other". thats the bit I don't get. @Jimmyblues1959 thanks for your post but unless I am mistaken, even with a 4.4mm to 3.5mm balanced jack, you are not getting a balanced input into your T60rp, you are just converting the 4.4mm socket to a 3.5mm socket, but without the proper full balanced cable, you are just getting regular unbalanced stereo right?

edit: ok i asked chatgpt. I get it now. So the 4 pole end of the regular cable is just to ensure maximum compatibility and security when plugged into the t60rp, it does not allow a balanced input. An unbalanced 3.5mm jack does the same job, it's kind of unnecessary. I will need to borrow/build/steal a way to get one.

 

[Longfellow78]

Oh dear. I found the cable I bought was listed as being compatible with T60tp.
I guess it was mis-sold then. I could cut the end off but I think it would be difficult to tell which cable was which. Maybe just buy a more expensive one... I am still none the wiser about the stock T60tp cable though!

 

[Longfellow78]

I decided to make a balanced 4.4 cable for my Fostex T60RP.
I took the pinout from the manual that came with the headphones. I soldered the cable, and it converts the audio signal to mono - this is interesting. Where did I (or someone at Fostex) make a mistake? I downloaded the PDF manual from the Fostex website - the pinout is different, not the same as in the paper manual - it’s strange!
Then I disassembled the headphones and checked the pinout of the connector - it corresponds to the pinout on the PDF manual from the website. Fostex provided incorrect information in the paper manual that came with the headphones. If you want to make a balanced cable according to this manual, you will not succeed, the sound will be mono.
The correct pinout will be L+ R+ L- R- (wrong L+ R+ R- L-)
For an unbalanced connection, it does not matter how the negative contacts are located because they are connected into one, but for a balanced connection this is important.

Cool. I saw you posted this. Thanks. Sorry for being dumb - is the paper essentially showing the wiring of the stock fostex cable, and you used this to understand how the socket was wired and hence made your own cable, Is that why the paper image shows two jacks, a 3 pole and a 4 pole? But as i understand it the balanced 4.4mm has 5 poles on the amp end, and 4 poles on the headphone end, so I'm not clear - or can you use 4 pole on both ends that are L+ R+ L- R- ?

 

[Jimmyblues1959]

Cool. I saw you posted this. Thanks. Sorry for being dumb - is the paper essentially showing the wiring of the stock fostex cable, and you used this to understand how the socket was wired and hence made your own cable, Is that why the paper image shows two jacks, a 3 pole and a 4 pole? But as i understand it the balanced 4.4mm has 5 poles on the amp end, and 4 poles on the headphone end, so I'm not clear - or can you use 4 pole on both ends that are L+ R+ L- R- ?

For what it's worth the 4.4mm to 3.5mm cable for the Fostex T60RP is being sold as a balanced cable. You
may want to call a manufacturer of any of these cables to find out out if they are truly balanced.

 

[Longfellow78]

For what it's worth the 4.4mm to 3.5mm cable for the Fostex T60RP is being sold as a balanced cable. You
may want to call a manufacturer of any of these cables to find out out if they are truly balanced.

Thanks I have investigated this now. The aftermarket cables they sell are indeed balanced, but the one that comes in the box as stock with a 3 pole on one and and a 4 pole on the other definitely isn't (unless they did a special for some versions which included an additional balanced cable in the box). I have bought myself some connectors and some balanced cable and will solder one up for myself. Will be about £18. About a quarter of the price of the official Fostex one! Thanks

 

[freemental]

Cool. I saw you posted this. Thanks. Sorry for being dumb - is the paper essentially showing the wiring of the stock fostex cable, and you used this to understand how the socket was wired and hence made your own cable, Is that why the paper image shows two jacks, a 3 pole and a 4 pole? But as i understand it the balanced 4.4mm has 5 poles on the amp end, and 4 poles on the headphone end, so I'm not clear - or can you use 4 pole on both ends that are L+ R+ L- R- ?

Please read this article, it contains details of how balanced connections differ from unbalanced ones, and there is also a description of the 4.4 connector
https://www.headphonesty.com/2019/05/balanced-vs-unbalanced-audio-connections/

 

[bru87tr]

I use a balanced cable from Hart Audio. I got it for my Oppo PM-3, but they are wired the same and it works fine on my T60.

 

[Longfellow78]

Please read this article, it contains details of how balanced connections differ from unbalanced ones, and there is also a description of the 4.4 connector
https://www.headphonesty.com/2019/05/balanced-vs-unbalanced-audio-connections/

Hi. thanks. I have bought some bits which I think are right. Please can you confirm my understanding so i can solder. I have a balancxed cable with 2 blue and 2 white wires which I will test for connection with my ammeter, and it has copper grounding. Please see the attached pics. My understanding is that I use the 5 pole cable with the connections for t60rp in the picture based on your explanation before from fostex pdf wiring diagram (if the picture correct?) Then if so on the other 4 pole connector, I don't know which poles - A, B, C, D, correspond to L+, R+, L-, R-. Is is L+ = A, R+ = B, L- = C, R- = D? And is the ground unconnected at the 3.5mm end? thanks!

 

[freemental]

just solder the wires on the connectors this way

 

[Longfellow78]

just solder the wires on the connectors this way

Oh Awesome thanks!