Google Pixel 4a Smartphone Audio Review

[Matias]

See the Hidizs S8 review. Same device

No, I meant the non-Pro version.
http://www.tempotec.com.cn/en/2-Product/Sonata/SonataHD/index.htm

 

[Thomas savage]

No, I meant the non-Pro version.
View attachment 84894

It's go the hirez sticker on it so I'm sold !

 

[maverickronin]

for IEMs it seems decent enough no?

Power wise, yes, but the output impedance is too high for a lot of BAs.

 

[Soniclife]

I don't know but for me this is kind of irrelevant as one can get a supposedly good measuring dongle like TempoTec Sonata HD (to be measured by Amir sometime) for 30usd which should measure a lot better than the phone's DAC.

Dongles are a horrible solution when on the go, I'd rather put up with the low output, mainly because I never listen loud from my phone.

 

[Jimbob54]

No, I meant the non-Pro version.
http://www.tempotec.com.cn/en/2-Product/Sonata/SonataHD/index.htm

View attachment 84894

My bad, sorry. Too many pro/ non pro HD sonatatecs floating round

 

[Tks]

Can you test the S8 at the same output level just to see when they're level matched, how it compares?

 

[Matias]

Dongles are a horrible solution when on the go, I'd rather put up with the low output, mainly because I never listen loud from my phone.

To me it's just an extension of the headphone cable, no big deal, as long as the distortion is lowered significantly and I get some higher power as well.

 

[Razorhelm]

Anyway, google maybe aims for some upcoming EU/US guidelines for hearing protection by aplying fixed power limiter..

I'm fairly certain this is right, i remember the first EU ear protection law coming out and all my devices which had updatable firmware lost a ton of volume!


Just had a thought there might be a hidden option somewhere in settings to turn off the limiter for those of you outside the EU.

 

[Dro]

50 mV SNR would have been interesting. I assume most users would use a highly sensitive IEM with a phone than a full-sized headphone. And getting 1 V RMS is not desirable when it gives you hearing damage and a tiny volume control range.

 

[YSC]

Power wise, yes, but the output impedance is too high for a lot of BAs.

True, I didn't noticed that at a quick glance!

Dongles are a horrible solution when on the go, I'd rather put up with the low output, mainly because I never listen loud from my phone.

I agree with that, maybe not that different when using on desktop solution, but when put into handbag or pants pockets that puts great stress at both the dongle and the phone port, my wife's iPhone 8 lightening jack died like 4 months with daily commute use with the dongle and repairing cost a fortune

 

[Vasr]

Not an expert on this but doesn't the ability to provide higher voltage have an impact on battery life?

 

[Prutser]

Too be hounest I am a bit curious about the dehydrated fruit and other garden stuff. Interesting too see an off topic article about that on ASR ?! Just kidding.

 

[Jimbob54]

I'm fairly certain this is right, i remember the first EU ear protection law coming out and all my devices which had updatable firmware lost a ton of volume!


Just had a thought there might be a hidden option somewhere in settings to turn off the limiter for those of you outside the EU.

I think they ship differently - if you have an EU compliant one , youd have to root or use UAPP to circumvent.

 

[Sukie]

Completely off topic but the picture

on the review has reminded me that the new Sufjan Stevens album came out yesterday.

I shall enjoy listening to it - just not on this phone!

Not an expert on this but doesn't the ability to provide higher voltage have an impact on battery life?

I don't do a lot of listening on the go but was considering the Tempotec Sonata HD Pro. I know that there are threads on this but how draining on battery life is it? (Sorry for being lazy).

 

[Chromatischism]

Not an expert on this but doesn't the ability to provide higher voltage have an impact on battery life?

Yes. When I enable the extra headphone amp to drive 300 ohm AKGs with my LG phones, you can almost watch the battery drain.

 

[composer]

I guess that low levels on smartphones are due to sueing-avoidance for causing deafness to listeners...
They likely have had many.
So, regardless of frustrating listening experience for end users, they stay ultra-safe with level, in order to be "case-proof"

It looks silly, and it definitely is, but I guess is for that

 

[Jimbob54]

Completely off topic but the picture

on the review has reminded me that the new Sufjan Stevens album came out yesterday.

I shall enjoy listening to it - just not on this phone!


I don't do a lot of listening on the go but was considering the Tempotec Sonata HD Pro. I know that there are threads on this but how draining on battery life is it? (Sorry for being lazy).

I think between the streaming of music and the use of the TSHD pro, i had noticeable battery drain when using in the car. An hour drive would have a significant dip in battery (10-15%)- but I cant separate the dongle drain from the streaming app use.

 

[Vasr]

Given the battery life is an over-riding issue in these units with very high trade-offs, the singular obsession on output voltage seems out of context. The saved battery draw may be helping some other functional trade-offs on the phone (not just total life).

As they are not designing these to be an audio unit (different from having an audio feature), good over-all engineering decision might be:

1. Provide for a good audio experience for a subset of HP/IEMs through analog out using default built-in controls that promote least battery usage and safe listening levels (whether mandated or based on recommendations from the medical profession). So consumers just plugging in whatever headphones they have (90%+ use case) aren't adversely affected.
2. Allow custom apps to be used for increasing the output via analog that lets those that want to take responsibility for it opt-in for less battery life and possible hearing damage but able to use their choice of headphones.
3. Use digital outs for connectivity to external devices that can provide additional amplification.

That seems like a more sensible engineering decision/challenge than engineering it to provide 2v of audio output so that any headphone can be used.

Am I wrong on this?

 

[Crandall]

The DAC chip on the Pixel 4a is the Qualcomm WCD 9370. Looks like the stated measurements on their website match up with Amir's measurements fairly closely.

https://www.qualcomm.com/products/wcd9370

 

[stunta]

Given the battery life is an over-riding issue in these units with very high trade-offs, the singular obsession on output voltage seems out of context. The saved battery draw may be helping some other functional trade-offs on the phone (not just total life).

As they are not designing these to be an audio unit (different from having an audio feature), good over-all engineering decision might be:

1. Provide for a good audio experience for a subset of HP/IEMs through analog out using default built-in controls that promote least battery usage and safe listening levels (whether mandated or based on recommendations from the medical profession). So consumers just plugging in whatever headphones they have (90%+ use case) aren't adversely affected.
2. Allow custom apps to be used for increasing the output via analog that lets those that want to take responsibility for it opt-in for less battery life and possible hearing damage but able to use their choice of headphones.
3. Use digital outs for connectivity to external devices that can provide additional amplification.

That seems like a more sensible engineering decision/challenge than engineering it to provide 2v of audio output so that any headphone can be used.

Am I wrong on this?

I manage a large team of engineers. I would cut or punt #2 without blinking an eye, target the 90% market and move on to higher priority features.

This is one area where I find ASR disconnected from reality. Sacrificing battery life or engineering cycles to satisfy a niche market in a $400 phone makes no sense. How many users do we expect to walk around with this phone and an HD650?