FiiO Q7 Portable Desktop-Class DAC and Headphone Amplifier Discussion & Impressions Thread

[godog]

Can the rgb light be turned off?

 

[EdgeDC]

Apologies if I have just missed the information somewhere. What are the power output specs at higher impedances?

According to the Q7 specs page:

Single Ended:
With Super High (SH) gain (battery power): 65 mW @ 300 Ω
With Ultra High (UH) gain (DC power): 130 mW @ 300 Ω

Balanced:
With Super High (SH) gain (battery power): 260 mW @ 300 Ω
With Ultra High (UH) gain (DC power): 500 mW @ 300 Ω

 

[DarginMahkum]

Looks like a full MQA decoder with the ES9038pro. And has balanced LO.
Here's the specs:

https://fiio.com/Q7_parameters

For those interested, there are also some measurements under the link:

Distortion diagram of curves 6
Test conditions： -12dB Sinusoidal signal，20Hz-20kHz，PO(BAL) SH gain(32Ωloaded)

 

[bflat]

Yes. Should arrive soon.

I'd be surprised if there was a significant difference between having one or two DAC chips. I'll test and find out.

Well at least folks won't have to ask if SE output uses both DAC chips. Unless there is such a thing as the single DAC chip operating in half mode.

 

[Ichos]

Well at least folks won't have to ask if SE output uses both DAC chips. Unless there is such a thing as the single DAC chip operating in half mode.

The ES9038PRO is an 8 channel DAC chip that can be operated in fully balanced and differential mode with one piece only.

 

[Ben86]

The ES9038PRO is an 8 channel DAC chip that can be operated in fully balanced and differential mode with one piece only.

So you mean that when i plug my headphones with 3.5 mm jack in my M17, it will use only one dac chip in music playback?

 

[EdgeDC]

So you mean that when i plug my headphones with 3.5 mm jack in my M17, it will use only one dac chip in music playback?

Yep - and only one amp module too. That's a big reason why balanced connections have much more power available compared to single ended.

 

[Ichos]

So you mean that when i plug my headphones with 3.5 mm jack in my M17, it will use only one dac chip in music playback?

Yep - and only one amp module too. That's a big reason why balanced connections have much more power available compared to single ended.

No.

Both DAC chips and amplifier modules are used and then a balanced to single ended convention is used for the single ended output.

Wrong.

 

[EdgeDC]

No.

Both DAC chips and amplifier modules are used and then a balanced to single ended convention is used for the single ended output.

Interesting - I swear I have always heard otherwise... unless it was a different situation in some previous FiiO products?

 

[Ichos]

The working principle is like this.
I can't find the M17 schematics but I am attaching one from the M11 Plus.

 

[EdgeDC]

The working principle is like this.
I can't find the M17 schematics but I am attaching one from the M11 Plus.

In your example, where does the output from the lower THX amp connect to the single-ended output? It doesn't appear to at all. If that is the case, then only the upper amp is used to drive the single-ended output, and therefore only 1 amp is used for SE, but both are used for balanced.

 

[Ichos]

In your example, where does the output from the lower THX amp connect to the single-ended output? It doesn't appear to at all. If that is the case, then only the upper amp is used to drive the single-ended output, and therefore only 1 amp is used for SE, but both are used for balanced.

Yes regarding the amplifier module you are absolutely right.
Both DAC chips are used but for the single ended output one chip and amp are utilized.

My mistake

 

[Ichos]

So because I messed things a little.

For the Q7 we do get differential signals (L+,L-,R+,R-) from one ES9038PRO DAC chip that feed two THX amplifier modules but for the single ended output only one path is used.

@JamesFiiO can kindly confirm?

 

[DarginMahkum]

Well at least folks won't have to ask if SE output uses both DAC chips. Unless there is such a thing as the single DAC chip operating in half mode.

As said before, dual DAC ES9038PRO is anyway an overkill, mostly to satisfy the audiophile more DAC chip hunger. RME ADI-2, for example, uses only a two channel ESS chip and performs far beyond the limits of what the ears can hear. For your question, multichannel (more than two) DACs have a stereo mode where 4 channels are assigned to left and the other 4 to the right. AKM 4499 DACs which are 4 channels also can use 2x2 configuration. 8 channels are actually for surround implementation. From ES9038PRO datasheet, check stereo mode:

 

[FiiO]

Apologies if I have just missed the information somewhere. What are the power output specs at higher impedances?

Dear friend,

You could check the parameter in our website now: https://www.fiio.com/q7_parameters
3.5mm/6.35mm，USB DAC/OPT/COAX，UH gain:

Output power

1500mW (16Ω，THD+N＜1%)

1100mW (32Ω，THD+N＜1%)

130mW (300Ω，THD+N＜1%）

3.5mm/6.35mm，USB DAC/OPT/COAX，SH gain)

Output power

750mW (16Ω，THD+N＜1%)

550mW (32Ω，THD+N＜1%)

65mW (300Ω，THD+N＜1%）

2.5mm/4.4mm，USB DAC/OPT/COAX，UH gain

1500mW (16Ω，THD+N＜1%)

3000mW (32Ω，THD+N＜1%)

500mW (300Ω，THD+N＜1%）

2.5mm/4.4mm，USB DAC/OPT/COAX，SH gain

1500mW (16Ω，THD+N＜1%)

1500mW (32Ω，THD+N＜1%)

260mW (300Ω，THD+N＜1%）

Best regards