[thirtyCruisers]

Hi everyone.
Will the q5 with the stock amp be able to drive a pair of dt770 250 ohm or, say, a fostex t40rp/t50rp? If not, what about the am5?
I looked through the thread and found only a little info abot the fostex, stating it is decent but not perfect for the task. Did anyone else try the q5 with either of the headphones?
Thanks!

 

[Grayven]

i use the balanced connection with my ZMF Blackwoods and it drives it fine.

 

[kukkurovaca]

Hi everyone.
Will the q5 with the stock amp be able to drive a pair of dt770 250 ohm or, say, a fostex t40rp/t50rp? If not, what about the am5?
I looked through the thread and found only a little info abot the fostex, stating it is decent but not perfect for the task. Did anyone else try the q5 with either of the headphones?
Thanks!

I don't have the Q5, but based on specs, I would expect the single-ended output of Q5 to be a little anemic for the T50RP/etc.

AM5 should have no problem, however.

 

[stemplar]

I don't have the Q5, but based on specs, I would expect the single-ended output of Q5 to be a little anemic for the T50RP/etc.

AM5 should have no problem, however.

since I have Q5 : Am3B 300ohm-70mW (balanced) vs. Am5 300 ohm 55mW (only unbalanced)((AM3A 300 ohm 63 mW (balanced) )) I bought the AM3B for the + 7mW and it was worth it, the HD650, which is hard to drive. It is not anemic, it can drive with great dynamics.

 

[Lay.]

I bought the AM3B for the 4.4mm pentaconn. In my opinion both AM3A and AM3B can drive HD800S quite nicely with balanced out, but AM3B has slightly warmer sound which I like.

AM3A and 24mW 300ohm from single ended out is not enough for harder to drive headphones.

 

[fgfgfg0923]

To improve the SQ dramatically - do the thing.
OPA1642 is the trash for LPF

Spoiler

 

[KopaneDePooj]

Hi @FiiO ! How's it going?

Is there really no way to be able to use one of the USB ports for digital signal only, and NO charging? Since we have two ports?
I use my Q5 80% of the time at my work desk, connected to my PC, so it's always charging. I use Bluetooth maybe 1 to 1.5 hours/day, and my battery is always between 90% - 100% which is NOT very good.
I would like to have longer discharge cycles, so I would like to be able to switch off charging completely while connected to PC.
At least can it be done using a special cable or adapter with my PC, the same way as your OTG cable for smartphones that is not charging the Q5?

 

[stemplar]

Hi @FiiO ! How's it going?

Is there really no way to be able to use one of the USB ports for digital signal only, and NO charging? Since we have two ports?
I use my Q5 80% of the time at my work desk, connected to my PC, so it's always charging. I use Bluetooth maybe 1 to 1.5 hours/day, and my battery is always between 90% - 100% which is NOT very good.
I would like to have longer discharge cycles, so I would like to be able to switch off charging completely while connected to PC.
At least can it be done using a special cable or adapter with my PC, the same way as your OTG cable for smartphones that is not charging the Q5?

Works with IOS, not on Android. However, the factory Fiio (!) OTG cable consumes only max 180-200 mAmp, I do not know what to do with the LG V30. (5 hours of silent listening 10%) (I bought a Cable Selecion OTG cable which in turn In vain, better quality, gold-plated. But ..1800-2000! MAmp was consumed ..So no matter what OTG cable you are using. At the same time, the side USB can be used nicely in use, even from the power bank.

 

[stemplar]

To improve the SQ dramatically - do the thing.
OPA1642 is the trash for LPF

Spoiler

And what? Are you replacing something right?

 

[fgfgfg0923]

And what? Are you replacing something right?

MUSES8832, you can check stock photos under the spoiler

 

[KopaneDePooj]

Works with IOS, not on Android. However, the factory Fiio (!) OTG cable consumes only max 180-200 mAmp, I do not know what to do with the LG V30. (5 hours of silent listening 10%) (I bought a Cable Selecion OTG cable which in turn In vain, better quality, gold-plated. But ..1800-2000! MAmp was consumed ..So no matter what OTG cable you are using. At the same time, the side USB can be used nicely in use, even from the power bank.

I think you missed the meaning of my post. I don't care about IOS or Android or OTG, I was just asking it there is a possibility to completely switch off charging WHEN I USE THE Q5 WITH MY PC, so that my battery can discharge longer, and reach for example 30-40% and not always stay between 90-100% as is the case with my usage pattern.

 

[fgfgfg0923]

I think you missed the meaning of my post. I don't care about IOS or Android or OTG, I was just asking it there is a possibility to completely switch off charging WHEN I USE THE Q5 WITH MY PC, so that my battery can discharge longer, and reach for example 30-40% and not always stay between 90-100% as is the case with my usage pattern.

Unsolder USB power leg in AM3A, one usb data only, one charging only

 

[KopaneDePooj]

Unsolder USB power leg in AM3A, one usb data only, one charging only

Thanks, but I'm not comfortable with such drastic solutions

And now I found that it can't be done, according to this page:
https://cambrionix.com/faq/can-i-sync-transfer-usb-data-without-charging/

"Due to the requirements of the USB specification (available from USB.org) it is not possible to maintain a data connection to a USB device without the presence of the USB VBUS voltage. With USB, VBUS (5V from the host cable) must be connected to the downstream device even if it is self-powered."

 

[fgfgfg0923]

Thanks, but I'm not comfortable with such drastic solutions

And now I found that it can't be done, according to this page:
https://cambrionix.com/faq/can-i-sync-transfer-usb-data-without-charging/

"Due to the requirements of the USB specification (available from USB.org) it is not possible to maintain a data connection to a USB device without the presence of the USB VBUS voltage. With USB, VBUS (5V from the host cable) must be connected to the downstream device even if it is self-powered."

Well, I know that 3-wire connection works for OTG, Post #437

 

[KopaneDePooj]

Well, I know that 3-wire connection works for OTG, Post #437

Then maybe a custom cable for PC that mimics the OTG design?

Later edit : Some more on this : http://www.yourfinalsystem.com/cable-design-f-a-q/147-how-do-data-only-usb-cables-work