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Review and Audio Measurement of LG G7 ThinQ Smartphone

pwjazz

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Amir, I have an LG V35, which has the same quad DAC and headphone amp as the G7. If I plug the V35 output into my JDS Element headphone amp, the phone goes into "Line Output" mode, and outputs 1 Volt, RMS. If I load the left and right outputs of the V35 with 220 ohm resistors, the V35 goes into "High Impedance" headphone mode, and outputs 2 Volts, RMS.

Would it be worth my time to make an adapter or cable with those resistors, so the phone would always output 2 V RMS to my headphone amp? How would doing so affect the sound quality, if at all?
If your amp is loud enough (ie has enough gain) then you're fine.
 

Jimster480

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I'm not sure; but do you plan to use the phone to drive headphones or only as a DAC output into a pocket amp? Because I can tell you that my G7 really doesn't sound too wonderful due to its lackluster power output. Even my 1More Triple drivers or Quad drivers struggle with this phone.
 

bigx5murf

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The LG Quad DAC need to be tricked into high impedance mode to get full headphone amp power. You either need to root it, or use a 3.5mm extender on low impedance headphones.
 
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Thanks for both input. I'm going to use it for earphone (16-64ohm) only when I'm out. I have desktop setting at home (Topping D10 + O2 Amp)
It seems that korean version cannot be unlocked / rooted?
 

Cahudson42

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I believe Amir measured the G7 Quad DAC to have better performance than the D10. As a result, I took my D10 at home out of the loop and went direct to my Liquid Spark via LG's 3.5mm. Can't detect any difference. Certainly not worse. And one less device to worry about. (I found my D10 to be noise/cable and PS sensitive anyway).

Connecting the 3.5mm to your O2 should put the LG into it's 1V 'line out' mode. That works fine for my LS. If you are unhappy with that, you can force the LG into it's 2V 'high impedance' mode using a 220ohm 'impedance adapter' and 33ohm HP temporarily connected via a short extension. More info on this earlier in this thread.
 
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Greetings.

I have a LG G8 ThinQ (uses the same ES9218P SoC as the G7, V30/V30+, V35 and V40) and I was wondering if there is a way to bypass the internal amp and get the signal straight from the DAC to external amp without having to open and mod the device.

Most of my headphones have low impendance (35 ohm or less) and they sound horrible straight out of the phone. A friend is selling a JDS Labs Atom for a very nice price and I'm thinking of buying it and using on the phone.

These are the SoC internal details: http://www.esstech.com/index.php/en...og-converters/sabre-hifi-mobile-dacs/es9218p/

Thank you very much.
 

Jimster480

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Greetings.

I have a LG G8 ThinQ (uses the same ES9218P SoC as the G7, V30/V30+, V35 and V40) and I was wondering if there is a way to bypass the internal amp and get the signal straight from the DAC to external amp without having to open and mod the device.

Most of my headphones have low impendance (35 ohm or less) and they sound horrible straight out of the phone. A friend is selling a JDS Labs Atom for a very nice price and I'm thinking of buying it and using on the phone.

These are the SoC internal details: http://www.esstech.com/index.php/en...og-converters/sabre-hifi-mobile-dacs/es9218p/

Thank you very much.
There is a DAC mode that you can use. Look up how to use it but when you plug it into the PC there is a way to set it up to be a DAC only. Then it will do line output into whatever amp you are using.

I also have a G8 and I've been told you need to use this little adapter from amazon to actually activate the amp. Otherwise you are right; its really lackluster for lower power headphones.
 
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There is a DAC mode that you can use. Look up how to use it but when you plug it into the PC there is a way to set it up to be a DAC only. Then it will do line output into whatever amp you are using.

I also have a G8 and I've been told you need to use this little adapter from amazon to actually activate the amp. Otherwise you are right; its really lackluster for lower power headphones.
Amazing!

But do I need to Root or change the ROM? I looked for this options everywhere in my phone, and I just found a MIDI USB Mode.
 
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Greetings.

I have a LG G8 ThinQ (uses the same ES9218P SoC as the G7, V30/V30+, V35 and V40) and I was wondering if there is a way to bypass the internal amp and get the signal straight from the DAC to external amp without having to open and mod the device.

Most of my headphones have low impendance (35 ohm or less) and they sound horrible straight out of the phone. A friend is selling a JDS Labs Atom for a very nice price and I'm thinking of buying it and using on the phone.

These are the SoC internal details: http://www.esstech.com/index.php/en...og-converters/sabre-hifi-mobile-dacs/es9218p/

Thank you very much.
I have the V35, which has the same DAC/Amp as the G8. I also have a pair of HiFiMan Arya headphones which are also low impedance. The built-in amps in these phones are not enough to drive low impedance headphones - and do NOT use an adapter to trick the phone into high output mode. By doing so, you are asking the amp to put out roughly four times the power it is designed for into a low impedance load, and you risk destroying the output chip.

FYI - In normal mode, your phone puts out one volt RMS. Trick it with the adapter, and you get two volts RMS. That's still not enough. I have the JDS Atom amp. Get it. It puts out almost six volts RMS into 35 ohms, and that is enough. When you plug the headphones jack from your phone into the Atom, your phone will go into high impedance mode, which, for all intents, sends the DAC output straight to the Atom.
 
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So, there are 3 different modes, Normal Mode, High Output Mode and High Impendance Mode, right? High Output is the result of the adapter trick, and High Impendance bypass the internal AMP, right?

So what people usually call AUX Mode is actually the High Output Mode?

Every forum over the internet is telling me to plug the detachable cable on the LG first, then on the Headphone latter, but looks like this is dangerous.
 
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So, there are 3 different modes, Normal Mode, High Output Mode and High Impendance Mode, right? High Output is the result of the adapter trick, and High Impendance bypass the internal AMP, right?

So what people usually call AUX Mode is actually the High Output Mode?

Every forum over the internet is telling me to plug the detachable cable on the LG first, then on the Headphone latter, but looks like this is dangerous.
Yes, there are three modes - Normal mode is for headphones below 50 ohms, and puts out one volt RMS. High Output mode is for headphones above 50 ohms, and puts out two volts RMS. High Impedance mode is strictly for driving external amps, which have an impedance of thousands of ohms, and therefore, present almost no load. AUX mode is the High Impedance mode. I do not know if the amp stage is bypassed, but since there is no load on it and it is flat across far more than the 20 Hz to 20 KHz range, even if the signal still goes through the amp, there would be no audible effect on that signal.

And yes, using that adapter trick is dangerous. It bypasses the built-in power overload protections. The output stage is not designed for that much power, and the resulting stress and heat. You risk blowing the amp chip. If your headphones sound bad, driven solely by the phone, the phone is deliberately limiting its output power to prevent damage. Don't bypass that safeguard. Get an amp. Trust me - you'll be glad you did.

There is an app in the Play Store that will tell you which mode your phone is in. I think I paid $2 for it. It is supposed to work on the G8...

LG HiFi Status App
 
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Yes, there are three modes - Normal mode is for headphones below 50 ohms, and puts out one volt RMS. High Output mode is for headphones above 50 ohms, and puts out two volts RMS. High Impedance mode is strictly for driving external amps, which have an impedance of thousands of ohms, and therefore, present almost no load. AUX mode is the High Impedance mode. I do not know if the amp stage is bypassed, but since there is no load on it and it is flat across far more than the 20 Hz to 20 KHz range, even if the signal still goes through the amp, there would be no audible effect on that signal.

And yes, using that adapter trick is dangerous. It bypasses the built-in power overload protections. The output stage is not designed for that much power, and the resulting stress and heat. You risk blowing the amp chip. If your headphones sound bad, driven solely by the phone, the phone is deliberately limiting its output power to prevent damage. Don't bypass that safeguard. Get an amp. Trust me - you'll be glad you did.

There is an app in the Play Store that will tell you which mode your phone is in. I think I paid $2 for it. It is supposed to work on the G8...

LG HiFi Status App
Thanks you very much, I will get the Atom ASAP.

Know I just need to know how can I use the LG as a PC USB DAC.
 
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Thanks you very much, I will get the Atom ASAP.

Know I just need to know how can I use the LG as a PC USB DAC.
You're welcome. Even at two volts RMS, your 35 ohm headphones would only be getting just over a tenth of a watt. The Atom Amp will give you a full watt RMS per channel. That's a tenfold increase, and will make a huge difference.

Once you get the Atom, let us all know what you think of it.

There may be a way to use the phone as a DAC, but if there is, I've never heard mention of it. To do so, you'd need to input a signal to the USB connector on the phone. I know you can use the USB connector as an output to feed a DAC, but I don't know if you can use it the other way around. You might be best just getting an inexpensive, dedicated DAC for your PC.
 
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