[DBaldock9]

v10d

Indeed! Three different procedures are involved, depending on the model:

1) Open Market V30/V30+/V30S models (such as your US998 and the European H930) come with fully functional fastboot, they just require an unlock.bin file from LG to unlock their bootlader. However LG reneged on their promise to provide this unlock file for many Open Market models. Through a freaky coincidence, XDA member TxanMoe discovered a bootloader vulnerability that allowed pretty much any file to be used to unlock the bootloader. This is the so-called "What" procedure linked by @gimpy (named after TxanMoe's reaction when he stumbled upon this). Again, here.

2) Carrier V30 models lack fully functional fastboot, but it turns they can be cross-flashed with firmware for the Open Market model for their respective region. So all North American models (except T-Mobile H932 - attempt no landing there) can be converted to US998 and thus get full fastboot. This is the so-called "Frankenstein" method (dubbed by XDA member Moriatier who discovered it). Described here.

3) Until recently, T-Mobile H932 models were the exception to this V30 root panacea: H932 does allow bootloader unlock outright, but lacks complete fastboot, so nothing can be flashed after unlocking. And due to its unique RSA encyption signatures, H932 cannot be Frankensteined to US998. But a H932 root procedure was finally posted in September by reverse engineering genius and XDA member runningnak3d. This is the so-called LAFsploit procedure (so named because it exploits a vulnerability in the laf partition that contains LG Download mode). It requires downgrading to Nougat v10d first. Described here.

So, all V30 models worldwide are now rootable, and we have TWRP, and a decent selection of ROMs, and active developers. While still not as developer friendly as Pixel or OnePlus phones, the V30 is still a great and affordable platform. AND it has superior audio

Thanks for the concise info.
It's been more than two months since I installed LineageOS (15.1-20180829-UNOFFICIAL-h930) on my V30, and I haven't checked to see if there are any updates.
The version of LinageOS on my V30 doesn't directly support the Hi Res Quad DAC, so I'm wondering whether there are better alternate ROM(s) that I should consider (my V30 is rooted with Magisk, and I run Xposed Framework)?
UAPP, with it's own audio subsystem driver, does support the Hi Res Mode - but I don't have control or feedback about the High Impedance / High Output modes.

 

[pilgrimbilly]

I bought my LG-US998 (USA Open Market V30), since LG provides the Bootloader Unlock file for that model - so I could install LinageOS.
When you say that all models can now be rooted, does that mean the Bootloader can also be unlocked on them - for installing alternate ROMs?

If you install Lineage, you lose the quad DAC (unless you use UAPP).

 

[Fralle]

The Tidal app does indeed work well with V30 and the Quad DAC, as long as you play MQA (Master) tracks. When you play non-MQA tracks in the Tidal app, it will use the Android Mixer path which up-samples Redbook 44.1Khz to 48KHz. It still uses the Quad DAC, but the up-sampling can introduce subtle artifacts as described in @csglinux' thread Music Apps, Tips and Tricks for the LG V30. UAPP is the only way I know to play redbook Tidal tracks directly through the Quad DAC without up-sampling. Of course that precludes offline mode.

I have not experienced UAPP shutting down when playing Tidal, but I have experienced it pausing and stuttering. It helps to change UAPP settings: Increase Settings-System-Network buffer size and Settings-System-Network chunk size and Settings->HiRes audio->Buffer size.

I have no firsthand experience with other phones and Tidal: Members in this thread and the head-fi V40 thread have posted mixed reports about the audio quality of V40, which is tuned differently than the V30. The V40 is a bit larger and taller than the V30, if that is a factor for you. Of course V40 is faster (SD845 vs 835, 6GB RAM vs 4GB). My understanding is that audio works the same on G7 as on V30, but it lacks OLED screen and has a smaller battery.

V30 is kind of a sweet spot: All models now have root (which helps prolong its useful life) and it can be bought at great prices on eBay and elsewhere. If I were in the market for a new phone right now, I would buy V30 in a heartbeat. If you can get the V30S (same phone with 6GB RAM) that would be even better.

Thank you! How much should I increase it?

 

[Dannemand]

Thanks for the concise info.
It's been more than two months since I installed LineageOS (15.1-20180829-UNOFFICIAL-h930) on my V30, and I haven't checked to see if there are any updates.
The version of LinageOS on my V30 doesn't directly support the Hi Res Quad DAC, so I'm wondering whether there are better alternate ROM(s) that I should consider (my V30 is rooted with Magisk, and I run Xposed Framework)?
UAPP, with it's own audio subsystem driver, does support the Hi Res Mode - but I don't have control or feedback about the High Impedance / High Output modes.

I cannot recommend any particular ROMs as I have not rooted my V30 yet (T-Mobile H932). I still have another year of warranty left on it, which I don't want to lose by rooting. And so far stock ROM has been OK for me with some bloat removed using ADB. I imagine once LG begins rolling out Android Pie on V30, it will increment the ARB counter (Anti-Roll-Back) to prevent users from downgrading. That will probably be the time when I root.

As you (and @pilgrimbilly) pointed out, some (most/all?) custom ROMs will lose Quad DAC support -- but I assume ONLY in cases when the standard Android Audio Mixer path is used, which means ONLY in those cases that would up-sample Redbook 44/16 to 48/16, which I don't want anyway. So yes, UAPP (and presumably Neutron), which use Direct audio routing, would still use the Quad DAC. And I would assume Tidal still uses the Quad DAC as well when playing MQA, as that also goes through the Direct route. I would love confirmation of this, though, from a custom ROM user. To verify it, use ADB as described towards the bottom of this UAPP support page.

The question is which Quad DAC settings are being used (Sound preset and Digital filter) as they are controlled with LG software that sets up the DAC. Certainly a custom ROM with Quad DAC support is preferable.

As for verifying the gain mode (Hi-Fi, Aux, High Impedance) I would assume the Hi-Fi Status app from Play Store still works. I personally belong in the camp that believes gain mode does NOT affect sound signature (as long as Bit Perfect and no adapters on the chain) and I am happy to just use Aux mode (easily achieved by plugging the cable into the phone before plugging it into my headphones). I believe it also saves battery.

Thank you! How much should I increase it?

I have Network buffer size=10 seconds, Network chunk size=256kB, Buffer size=600ms. The last one (Buffer size) probably doesn't even affect network streaming.

I actually don't use UAPP to stream Tidal much anymore because the battery use is quite excessive when streaming. Instead, I play mostly through the Tidal app, where I can Download -- and almost entirely MQA tracks, which will play in the Tidal app without up-sampling.

 

[Damo77]

I find that using 3,5mm to 3.5mm adapter drives a lot more power to my RHA T20i IEMs. There does not seem to be any noticeable increase in noise or hiss doing this. This is using QOBUZ app that streams FLAC. Even from Spotify at their highest bit-rate of 320kbps feels better. I must get an adapter with the 3 rings though as my push button skip track no longer works with this approach

 

[Dannemand]

I find that using 3,5mm to 3.5mm adapter drives a lot more power to my RHA T20i IEMs. There does not seem to be any noticeable increase in noise or hiss doing this. This is using QOBUZ app that streams FLAC. Even from Spotify at their highest bit-rate of 320kbps feels better. I must get an adapter with the 3 rings though as my push button skip track no longer works with this approach

That makes sense: If the adapter pushes the impedance of the IEMs over 50 Ohms, that would kick the phone from Hi-Fi mode into High Impedance mode, significantly increasing output power. The added impedance from the adapter will then change the frequency response of the IEMs, so the sound signature is different, even after volume control is lowered to the same audible level as without the adapter. If you prefer that sound signature, all is well.

I would not expect any increase in noise or hiss going to higher gain modes (HiFi < Aux < HIM): If indeed the higher powered modes are achieved by activating more DAC units (as has been debated at great length in this thread and elsewhere, and as would make sense to me) then its purpose would be to multiply current fed to the OpAmp, so as to achieve a higher output voltage WITHOUT a proportionate increase in THD+N. However it would not affect sound signature or frequency response. At least to my understanding.

The reason I believe that it doesn't matter either way, is because THD+N is already so infinitesimally low in the ESS Sabre (and most modern Delta-Sigma DACs, I am told). The only time it would be audible is if you were to dramatically amplify output power -- such as for 250 Ohms headphones or planars. In those cases adding up the current from multiple parallel DAC units will multiply the current fed to the OpAmp. Thus requiring less amplification, THD+N will be proportionally lower than if the output from a single DAC unit had been amplified to the same output level.

But this would NOT change the sound signature: All DAC units work the same, they just add more current, with a proportionally lower noise floor in the final output. Low impedance IEMs require so little amplification that the noise from a single DAC unit wouldn't be audible anyway. By forcing HIM with such IEMs, the noise floor will be lowered from completely inaudible to even more completely inaudible.

That's my takeaway from the discussions about how the Quad DAC works, AND the measurements performed by members here, who have far more knowledge than me, excellent ears, and acces to audio analyzers and other equipment far beyond my reach. (You all know of whom I speak )

 

[borisov57]

Maybe someone knows, which volume settings (or difference between them) will produce same output level in normal and high impedance mode?

 

[Dannemand]

Maybe someone knows, which volume settings (or difference between them) will produce same output level in normal and high impedance mode?

I seem to recall that @csglinux had a way of calculating that. I could remember wrong; if so I apologize for the ping.

 

[borisov57]

Thanks Dannemand for replay. I have a filling, that high impedance sounds somehow more energetic. But it is very unpractical to carry along another cable and jack with resistors for triggering this mode. I would like to try it again with matched volume.

 

[EpicEric6]

Thanks Dannemand for replay. I have a filling, that high impedance sounds somehow more energetic. But it is very unpractical to carry along another cable and jack with resistors for triggering this mode. I would like to try it again with matched volume.

Definitely more punchy bass in high impedance mode.
Higher Vrms means more energy. Also note that there are significant benefit on SNR, dynamic range too.
Measurement from LG G7 can confirm this
https://imgur.com/gallery/fADatDd
Normal mode is just too weak for anything other than some IEMs.

 

[EpicEric6]

That makes sense: If the adapter pushes the impedance of the IEMs over 50 Ohms, that would kick the phone from Hi-Fi mode into High Impedance mode, significantly increasing output power. The added impedance from the adapter will then change the frequency response of the IEMs, so the sound signature is different, even after volume control is lowered to the same audible level as without the adapter. If you prefer that sound signature, all is well.

I would not expect any increase in noise or hiss going to higher gain modes (HiFi < Aux < HIM): If indeed the higher powered modes are achieved by activating more DAC units (as has been debated at great length in this thread and elsewhere, and as would make sense to me) then its purpose would be to multiply current fed to the OpAmp, so as to achieve a higher output voltage WITHOUT a proportionate increase in THD+N. However it would not affect sound signature or frequency response. At least to my understanding.

The reason I believe that it doesn't matter either way, is because THD+N is already so infinitesimally low in the ESS Sabre (and most modern Delta-Sigma DACs, I am told). The only time it would be audible is if you were to dramatically amplify output power -- such as for 250 Ohms headphones or planars. In those cases adding up the current from multiple parallel DAC units will multiply the current fed to the OpAmp. Thus requiring less amplification, THD+N will be proportionally lower than if the output from a single DAC unit had been amplified to the same output level.

But this would NOT change the sound signature: All DAC units work the same, they just add more current, with a proportionally lower noise floor in the final output. Low impedance IEMs require so little amplification that the noise from a single DAC unit wouldn't be audible anyway. By forcing HIM with such IEMs, the noise floor will be lowered from completely inaudible to even more completely inaudible.

That's my takeaway from the discussions about how the Quad DAC works, AND the measurements performed by members here, who have far more knowledge than me, excellent ears, and acces to audio analyzers and other equipment far beyond my reach. (You all know of whom I speak )

I believe that it will affect frequency response when more power is added. Bass response will improve due to higher voltage / current being feed into the headphone. I’m not 100% sure about the mechanism behind it. But I tend to believe that the most significant difference one can hear is the bass.
To me, I can clearly hear the difference in frequency response between normal, aux and Hi-Fi mode (albeit on a G7) with M50x and SHP9500.
This measurement in the link below could help you see the difference between modes.
https://imgur.com/gallery/fADatDd

 

[qsk78]

Hi.
Do klipsch IEM with 50 ohm activate High Impedance mode on the V30? Thanks.

 

[Dannemand]

I believe that it will affect frequency response when more power is added. Bass response will improve due to higher voltage / current being feed into the headphone. I’m not 100% sure about the mechanism behind it. But I tend to believe that the most significant difference one can hear is the bass.
To me, I can clearly hear the difference in frequency response between normal, aux and Hi-Fi mode (albeit on a G7) with M50x and SHP9500.
This measurement in the link below could help you see the difference between modes.
https://imgur.com/gallery/fADatDd

Thank you. Obviously different levels of output power delivered to the IEMs/headphones will affect the response of their drivers. And as I believe is well established, even small differences in volume can significantly affect the perception of a human listener. My only contention here is that it should not make a difference whether the increased power comes from additional DACs (multiplying current fed to the OpAmp) or from increased amplification by the OpAmp itself -- except on the THD+N, which is very low in all cases. And (if that is true) the audible difference between gain modes should be negligible in most cases, except for the volume difference.

But I could be completely wrong. My intent was not to argue strongly, as I simply don't have enough insight or understanding myself, nor the equipment needed for testing. I merely relayed my takeaway from the previous discussions in here, and the various (and oft quoted) articles and LG quotes. For anyone that have not read the full thread, I would recommend going back and study it. You may come out with a different conclusion than me.

The few informal tests I have performed myself were using this Monoprice TRS adapter along with this impedance adapter from eBay to trigger HIM (High Impedance Mode). Output was to an insanely high end sound system with a custom built preamp -> custom built Class D power amp -> Dali speakers. (A team of experienced audio and electronics experts, including one of the engineers behind the original B&O ICEpower technology, who have set out to develop the worlds best power amp using PWM technology. Their result so far is vastly better than anything else I've ever heard, including the already superb Dali Gravity they're using for reference comparisons.) In those V30 tests, Aux mode (with no adapter) was quite a bit clearer and more open than HIM (through the TRS adapter, but of course with the impedance adapter removed after HIM was triggered). Further tests in Aux mode, with and without the TRS adapter, revealed that the adapter alone caused significant degradation. A second TRS adapter (same model) was a bit better, but still audibly worse than without adapters.

So my conclusion from studies in this thread and my own anecdotal tests, is that any differences between modes that involve adding adapters on the output chain in order to achieve HIM, are more likely to be caused by the adapter. Obviously not all adapters are made equal, so if one wants to play through an adapter in order to force HIM, better make sure it's a good one!

I really don't want to argue beyond that, as I have neither the experience nor the equipment for it.

 

[alota]

Hi.
Do klipsch IEM with 50 ohm activate High Impedance mode on the V30? Thanks.

Probably. But sometimes the phone is crazy. I had kz 5 and 6 iem. Same drivers. The 5 activate high impedance mode, the 6 normal mode

 

[monsieurfromag3]

Hi.
Do klipsch IEM with 50 ohm activate High Impedance mode on the V30? Thanks.

My x20i (50-ohm impedance) sadly don’t trigger it, without an extension I often reach volume 70 out of 75.

You can get more volume by playing through UAPP, which also improves SQ by bypassing the Android mixer.

As a Klipsch user you’d have to decide what’s clunkier/more annoying between plugging straight in but scraping max volume in Normal made, using an extension to trigger Aux mode, not High Impedance (Aux definitely provides enough volume though), or playing through UAPP (which doesn’t work well if you’re mobile - neither trying to stream in 4G or regularly switching Wifi connections).