[HiFiHawaii808]

You can change the gain for LO and PO.

I only have one gain setting for my AMP12.

Are you talking about AMP11? I think we discussed this before. IIFC, the AMP11 has 2 gain settings. TBH, the AMP11 Line out feature sucks. I stopped using it when I moved to AMP12.

 

[armstrj2]

I only have one gain setting for my AMP12.

Are you talking about AMP11? I think we discussed this before. IIFC, the AMP11 has 2 gain settings. TBH, the AMP11 Line out feature sucks. I stopped using it when I moved to AMP12.

That's odd. I have the H,M,L for both. Different Firmware maybe? (using AMP12)

 

[HiFiHawaii808]

That's odd. I have the H,M,L for both. Different Firmware maybe? (using AMP12)

Why would a Line out port need a gain setting?

 

[armstrj2]

Why would a Line out port need a gain setting?

I can't answer that as I don't know or understand the inner workings of the AMP12 but the option is there. I can only guess it is to allow you to decrease the output for circumstances where the full output would be too much for what you are connecting to.

 

[twister6]

Why would a Line out port need a gain setting?

That's how it is by design in DX300, Gain changes the output voltage level of both LO and PO. You probably haven't noticed because you have it in Medium gain. With LO connected to C9, try switching to Low gain, and you will hear a drop in volume level.

Following was the issue. DX300 default amp11 card didn't have a dedicated LO and its pseudo LO output has a spec of 7.1Vrms (in BAL, assuming in High Gain) which is a bit too high, and there was someone who damaged their C9 due to high voltage input from DX300 amp11 card. When you switch gain to med or low, 7.1Vrms voltage will drop, making it "safer" for C9 input. Amp12 card has a dedicated clean LO with a max output voltage of 4.1Vrms (in BAL, assuming in High Gain). For C9 this is a more ideal input voltage.

So, when using DX300 with amp11 and balanced LO to C9, better use low or med gain. When using amp12 card and C9, LO and high gain are OK.

And, in DX300 MAX, the dedicated LO also has max output voltage of 4.4Vrms (in high gain), which is OK as well when connected to C9.

 

[HiFiHawaii808]

That's how it is by design in DX300, Gain changes the output voltage level of both LO and PO. You probably haven't noticed because you have it in Medium gain. With LO connected to C9, try switching to Low gain, and you will hear a drop in volume level.

Following was the issue. DX300 default amp11 card didn't have a dedicated LO and its pseudo LO output has a spec of 7.1Vrms (in BAL, assuming in High Gain) which is a bit too high, and there was someone who damaged their C9 due to high voltage input from DX300 amp11 card. When you switch gain to med or low, 7.1Vrms voltage will drop, making it "safer" for C9 input. Amp12 card has a dedicated clean LO with a max output voltage of 4.1Vrms (in BAL, assuming in High Gain). For C9 this is a more ideal input voltage.

So, when using DX300 with amp11 and balanced LO to C9, better use low or med gain. When using amp12 card and C9, LO and high gain are OK.

And, in DX300 MAX, the dedicated LO also has max output voltage of 4.4Vrms (in high gain), which is OK as well when connected to C9.

Thank you for the clarification. This is helpful.

 

[ssriram2791]

That's how it is by design in DX300, Gain changes the output voltage level of both LO and PO. You probably haven't noticed because you have it in Medium gain. With LO connected to C9, try switching to Low gain, and you will hear a drop in volume level.

Following was the issue. DX300 default amp11 card didn't have a dedicated LO and its pseudo LO output has a spec of 7.1Vrms (in BAL, assuming in High Gain) which is a bit too high, and there was someone who damaged their C9 due to high voltage input from DX300 amp11 card. When you switch gain to med or low, 7.1Vrms voltage will drop, making it "safer" for C9 input. Amp12 card has a dedicated clean LO with a max output voltage of 4.1Vrms (in BAL, assuming in High Gain). For C9 this is a more ideal input voltage.

So, when using DX300 with amp11 and balanced LO to C9, better use low or med gain. When using amp12 card and C9, LO and high gain are OK.

And, in DX300 MAX, the dedicated LO also has max output voltage of 4.4Vrms (in high gain), which is OK as well when connected to C9.

Is DX300 AMP11 the only DAP that has Pseudo Line out with such high voltage output ? Most of the DAPs I have owned or read about have with balanced lineout voltage to be less than 4.5 Volts. Clarification on this would be much appreciated !

 

[armstrj2]

That's how it is by design in DX300, Gain changes the output voltage level of both LO and PO. You probably haven't noticed because you have it in Medium gain. With LO connected to C9, try switching to Low gain, and you will hear a drop in volume level.

Following was the issue. DX300 default amp11 card didn't have a dedicated LO and its pseudo LO output has a spec of 7.1Vrms (in BAL, assuming in High Gain) which is a bit too high, and there was someone who damaged their C9 due to high voltage input from DX300 amp11 card. When you switch gain to med or low, 7.1Vrms voltage will drop, making it "safer" for C9 input. Amp12 card has a dedicated clean LO with a max output voltage of 4.1Vrms (in BAL, assuming in High Gain). For C9 this is a more ideal input voltage.

So, when using DX300 with amp11 and balanced LO to C9, better use low or med gain. When using amp12 card and C9, LO and high gain are OK.

And, in DX300 MAX, the dedicated LO also has max output voltage of 4.4Vrms (in high gain), which is OK as well when connected to C9.

Fantastic. That's exactly the info I was looking for. Probably should have asked first. It would have saved me reading through 300 pages but some great info in there. Thanks

 

[HiFiHawaii808]

Fantastic. That's exactly the info I was looking for. Probably should have asked first. It would have saved me reading through 300 pages but some great info in there. Thanks

Bottom line is that using AMP12, there should be no problem with whatever gain setting you use.

To me, this says that AMP11 was poorly designed to support Line Out. Not surprising since it sucks.

 

[HiFiHawaii808]

I am travelling again this week and I brought my DX300 and C9 with my new Van Nuys case. I remembered that Spotify Connect allows me to control playback on different devices. So, I loaded Spotify on my DX300 and now I can control music from either my Apple Watch or iPhone. Totally cool. Just need Spotify to finally launch Spotify Hiifi and I will be all set.

 

[twister6]

That's how it is by design in DX300, Gain changes the output voltage level of both LO and PO. You probably haven't noticed because you have it in Medium gain. With LO connected to C9, try switching to Low gain, and you will hear a drop in volume level.

Following was the issue. DX300 default amp11 card didn't have a dedicated LO and its pseudo LO output has a spec of 7.1Vrms (in BAL, assuming in High Gain) which is a bit too high, and there was someone who damaged their C9 due to high voltage input from DX300 amp11 card. When you switch gain to med or low, 7.1Vrms voltage will drop, making it "safer" for C9 input. Amp12 card has a dedicated clean LO with a max output voltage of 4.1Vrms (in BAL, assuming in High Gain). For C9 this is a more ideal input voltage.

So, when using DX300 with amp11 and balanced LO to C9, better use low or med gain. When using amp12 card and C9, LO and high gain are OK.

And, in DX300 MAX, the dedicated LO also has max output voltage of 4.4Vrms (in high gain), which is OK as well when connected to C9.

I have to clarify this, actually in high gain LO with DX300/amp11 and C9, amp11 card was damaged, not C9. And I remember the person damaged amp11, replaced it with another amp11 and damaged it again. C9 was OK.

 

[Andykong]

Finally got my Van Nuys case for my C9. It's wonderful. Thanks to @masahito24@chart for helping me with the order. I met with him yesterday to pick up my case and he has some outrageous gear.

I want to see if I can actually listen to it in the case. I recall a discussion about HIBY Link. Anyone have instructions on how to set up it so that I can control my DX300 with my iPhone or Apple watch?

Can you control your DX300 with HiByLink on y our iphone? I was under the impression that HiByLink only compatible wiht HiBy based soluton.

 

[Andykong]

I don't have any trouble with the DX300 at max gain. I haven't followed this thread that closely. What does Andy Kong say?

Can't comment on the design of DX300. Forum rules.

That's how it is by design in DX300, Gain changes the output voltage level of both LO and PO. You probably haven't noticed because you have it in Medium gain. With LO connected to C9, try switching to Low gain, and you will hear a drop in volume level.

Following was the issue. DX300 default amp11 card didn't have a dedicated LO and its pseudo LO output has a spec of 7.1Vrms (in BAL, assuming in High Gain) which is a bit too high, and there was someone who damaged their C9 due to high voltage input from DX300 amp11 card. When you switch gain to med or low, 7.1Vrms voltage will drop, making it "safer" for C9 input. Amp12 card has a dedicated clean LO with a max output voltage of 4.1Vrms (in BAL, assuming in High Gain). For C9 this is a more ideal input voltage.

So, when using DX300 with amp11 and balanced LO to C9, better use low or med gain. When using amp12 card and C9, LO and high gain are OK.

And, in DX300 MAX, the dedicated LO also has max output voltage of 4.4Vrms (in high gain), which is OK as well when connected to C9.

I have to clarify this, actually in high gain LO with DX300/amp11 and C9, amp11 card was damaged, not C9. And I remember the person damaged amp11, replaced it with another amp11 and damaged it again. C9 was OK.

Thank you Alex for your recap and explanation. I can only advice from C9 perspective.

The C9 is designed to accept 4.4mm (BAL) Line level input at around 4V. If we used E02 Audio Motherboard as reference, the recommended setting is High LO level in E02

Unfortunately, there is no specific rules or guideline on output level from DAP line out. If a DAP decided to offer output level at High LO level = 6V, Mid LO level = 4V, Low LO level - 2V, that is perfectly legitimate. Therefore the correct approach is NOT to make a choice based on verbal description such as High or Mid or Low level. The most sensible approach is to find out the output level behind the High, Mid and Low description.

Once you find out the rated output level, just start with the setting that is closest to 4V. established your base line, then you can try different line out level setting for exploration.

How far can be deviated from the 4V line out level recommendation?

If we are talking about 10% different (i.e., 3.6V to 4.4V), that is perfectly alright.
If we are talking about 20%, 30% different (i.e., 2.8V to 5.2V), that is still within the normal operation range of C9.
If we are talking about 50% different (i.e, upto 6V), and I still claim that we are still in perfectly good condition, don't you think this is a bit non-precise for high fidelity application? Technically this is still safe, don't think anything will blow up, but if there is other choice that is closer to the designed value, maybe we should go for that instead.

For the record, Amp 11 High Line Out level delivers 7.1V at full volume, C9 didn't have much problem to pair with that. At lease one user said this combo/setting sounds very good. Unfortunately, the Amp 11 failed twice. Several experienced users explained that an amplifier cannot damaged upstream equipment because there is no feedback signal path, so there is no way C9 can cause any damage to Amp 11, but we still go blamed in that instance.

 

[Spawn300Z]

On the. Cruise with my portable setup.

 

[jwbrent]

On the. Cruise with my portable setup.

There’s a rumor that Chord is releasing the successor to the Mojo early next year, and that’s what I plan to use with my C9 after I buy it. I liked the Mojo, I liked it better than the Hugo I also had.

We are of the same mind, gotta have music on our travels.