• WANTED: Happy members who like to discuss audio and other topics related to our interest. Desire to learn and share knowledge of science required as is 20 years of participation in forums (not all true). There are daily reviews of audio hardware and expert members to help answer your questions. Click here to have your audio equipment measured for free!

Amazon Fire 7 Review

Helicopter

Major Contributor
Joined
Aug 13, 2020
Messages
2,684
Likes
3,889
Location
Michigan
When you say that, do you mean audio performance is good?
I have no way of testing - subjectively the 3.5mm audio sounds fine and loud enough on SHP9500, not as loud as I would like on my HE400i. It does work great USB OTG connected with a Qudelix 5k, while simultaneously running the Qudelix App controlling it via bt. Amazon music app running as well, for 16/44.1 streaming FLAC mostly.

I'm thinking it's worth looking at because of the Qualcomm Snapdragon, and likely(?) use of it's WCD9xx - hopefully similar to higher end LGs.

But without testing, we don't know :)

Tracfone has some great Black Friday deals on LG phones starting at $30 if you don't buy a plan. I'd be more interested in seeing results of late model units:

Stylo 6: May 18. 2020
Premier Pro Plus: 2020
Journey: 2019

Journey seems like the choice for the intended purpose at $30 right now.

I'd skip these:

Rebel 4: July 2018
Solo LTE: May 2019
Premier Pro LTE: 2018
 

Robin L

Major Contributor
Joined
Sep 2, 2019
Messages
4,726
Likes
6,781
Location
1 mile east of Sleater Kinney Rd
I've got the Fire 8, at least I had the Fire 8 until I handed it over to my wife, who reads books on it constantly. Set me back all of $50. Sonically, it's very weak and as a tablet its got its limitations. As regards the original intent, it's a fantastic bargain. Don't buy it for its sonics, do buy it to link to your library and read books.
 
Last edited:

The Jniac

Member
Forum Donor
Joined
May 14, 2018
Messages
85
Likes
131
Location
Greater Vancouver Area, Canada
No it’s an important review, there is a branch of the objectivist camp that truly believe that all these cheap dac/amp implementation are equal, transparent, sound the same, and that anybody who claim there is a difference are biased.

Well, to be fair, a lot of devices will indeed sound the same with proper blinding and level matching, especially if listening is done in a fairly typical room with 20-30dB of ambient noise. That said, there is a point where the performance is so poor that it will indeed have audible consequences, and the SINAD of this tablet could only clear the threshold for okay performance¹ with high-impedance loads that its abysmal voltage output would not be able to drive.

1: I place this threshold at 75dB, since the best-case dynamic range I was able to get out of my listening setup was about 75dB, but that required extreme measures including higher-than-normal listening volumes, using my ER4-XR, wearing my Brainwavz HM5 over top to further attenuate noise, listening late at night, and silencing all other noise sources in the room where I did the testing.
 

PeteL

Major Contributor
Joined
Jun 1, 2020
Messages
2,762
Likes
2,975
Well, to be fair, a lot of devices will indeed sound the same with proper blinding and level matching, especially if listening is done in a fairly typical room with 20-30dB of ambient noise. That said, there is a point where the performance is so poor that it will indeed have audible consequences, and the SINAD of this tablet could only clear the threshold for okay performance¹ with high-impedance loads that its abysmal voltage output would not be able to drive.

1: I place this threshold at 75dB, since the best-case dynamic range I was able to get out of my listening setup was about 75dB, but that required extreme measures including higher-than-normal listening volumes, using my ER4-XR, wearing my Brainwavz HM5 over top to further attenuate noise, listening late at night, and silencing all other noise sources in the room where I did the testing.
Sinad is a measure taken unloaded, you have to look beyond that to judge of a device that have the task of moving transducers, you are oversimplifying.
 

Beershaun

Major Contributor
Forum Donor
Joined
Oct 3, 2019
Messages
1,636
Likes
1,656
1: I place this threshold at 75dB, since the best-case dynamic range I was able to get out of my listening setup was about 75dB, but that required extreme measures including higher-than-normal listening volumes, using my ER4-XR, wearing my Brainwavz HM5 over top to further attenuate noise, listening late at night, and silencing all other noise sources in the room where I did the testing.

This is the criteria I use: https://www.audiosciencereview.com/...-thresholds-of-amp-and-dac-measurements.5734/
 

Shadow12347

Member
Forum Donor
Joined
Oct 29, 2018
Messages
30
Likes
54
1605905919740.png


Infected Mushrooms, eh? It makes me happy to see that :p

If I might make a suggestion, there's another song by them that I find to be quite good for comparing different qualities of audio. Check out Scorpion Frog from the Converting Vegetarians album. It has a really nice bass-line for testing sub-bass.
 
OP
amirm

amirm

Founder/Admin
Staff Member
CFO (Chief Fun Officer)
Joined
Feb 13, 2016
Messages
40,019
Likes
186,039
Location
Seattle Area
Well, to be fair, a lot of devices will indeed sound the same with proper blinding and level matching, especially if listening is done in a fairly typical room with 20-30dB of ambient noise. That said, there is a point where the performance is so poor that it will indeed have audible consequences, and the SINAD of this tablet could only clear the threshold for okay performance¹ with high-impedance loads that its abysmal voltage output would not be able to drive.
The issues are are not SINAD. It is 40 ohm output impedance which will severely modify the frequency response of many headphones. And lack of output to drive a decent headphone. This are quite audible effects to just about anyone.
 
OP
amirm

amirm

Founder/Admin
Staff Member
CFO (Chief Fun Officer)
Joined
Feb 13, 2016
Messages
40,019
Likes
186,039
Location
Seattle Area
View attachment 94722

Infected Mushrooms, eh? It makes me happy to see that :p

If I might make a suggestion, there's another song by them that I find to be quite good for comparing different qualities of audio. Check out Scorpion Frog from the Converting Vegetarians album. It has a really nice bass-line for testing sub-bass.
Thanks a bunch. Just pulled it up from Tidal and listening to it. Nice string instruments there as well.
 

infinitesymphony

Major Contributor
Joined
Nov 21, 2018
Messages
1,071
Likes
1,775
More of an OS question than anything else, but do these support USB audio devices? Wonder if you could run USB micro B to USB-C to an Apple audio adapter.

51k4yl7TJNL._AC_SX522_.jpg


That said, when MVNOs are offering higher-res phones with better audio performance for $50, even cheap devices like these are a hard sell unless you really need a large screen for interaction purposes.
 

Helicopter

Major Contributor
Joined
Aug 13, 2020
Messages
2,684
Likes
3,889
Location
Michigan
Thanks a bunch. Just pulled it up from Tidal and listening to it. Nice string instruments there as well.
Yeah. These guys got me through my late shift. I love the Hebrew vocals over heavy synth bass. Now I am debating purchase of $80 vinyl album I really don't need.... sic transit gloria mundi.
 

The Jniac

Member
Forum Donor
Joined
May 14, 2018
Messages
85
Likes
131
Location
Greater Vancouver Area, Canada

The Jniac

Member
Forum Donor
Joined
May 14, 2018
Messages
85
Likes
131
Location
Greater Vancouver Area, Canada
The issues are are not SINAD. It is 40 ohm output impedance which will severely modify the frequency response of many headphones. And lack of output to drive a decent headphone. This are quite audible effects to just about anyone.

I forgot to mention that. It is unfortunate that the output is so low that the only things it could likely drive to a decent volume would be things that would have their response mangled by the horrific output impedance.
 

The Jniac

Member
Forum Donor
Joined
May 14, 2018
Messages
85
Likes
131
Location
Greater Vancouver Area, Canada
Sinad is a measure taken unloaded, you have to look beyond that to judge of a device that have the task of moving transducers, you are oversimplifying.

Are you sure? He quite clearly has it marked that he took measurements, including SINAD, with 300 ohm and 33 ohm loads, with those impedances matching the values at the very bottom of his dashboard screenshots.
 
OP
amirm

amirm

Founder/Admin
Staff Member
CFO (Chief Fun Officer)
Joined
Feb 13, 2016
Messages
40,019
Likes
186,039
Location
Seattle Area
Are you sure? He quite clearly has it marked that he took measurements, including SINAD, with 300 ohm and 33 ohm loads, with those impedances matching the values at the very bottom of his dashboard screenshots.
I did all three variations. Unloaded and two loaded ones as you mention. The bottom display is not accurate since I use external loads for testing headphone amps (in some tests).
 

The Jniac

Member
Forum Donor
Joined
May 14, 2018
Messages
85
Likes
131
Location
Greater Vancouver Area, Canada
I did all three variations. Unloaded and two loaded ones as you mention. The bottom display is not accurate since I use external loads for testing headphone amps (in some tests).

Any idea what happened with the 33 ohm test? Unless I am misreading the graph, it looks like noise dropped, the first harmonic jumped about 14dB, and all the other harmonics dropped.
 
OP
amirm

amirm

Founder/Admin
Staff Member
CFO (Chief Fun Officer)
Joined
Feb 13, 2016
Messages
40,019
Likes
186,039
Location
Seattle Area
Any idea what happened with the 33 ohm test? Unless I am misreading the graph, it looks like noise dropped, the first harmonic jumped about 14dB, and all the other harmonics dropped.
Noise level looks the same to me. Different distortion mechanism has set in changing the profile. It is definitely under stress.
 

boblinds

Member
Joined
Aug 5, 2020
Messages
18
Likes
63
No it’s an important review, there is a branch of the objectivist camp that truly believe that all these cheap dac/amp implementation are equal, transparent, sound the same, and that anybody who claim there is a difference are biased.
Excellent point, Pete!!
 

PeteL

Major Contributor
Joined
Jun 1, 2020
Messages
2,762
Likes
2,975
Are you sure? He quite clearly has it marked that he took measurements, including SINAD, with 300 ohm and 33 ohm loads, with those impedances matching the values at the very bottom of his dashboard screenshots.
Fair enough, Yes I just looked at the first one, but really the one that matter is at 33 ohms for this, and it’s quite low. I find your threshold very low for modern use cases. you realize that in real life this SINAD is only true if there is no digital attenuation in the chain. and this 75 dB range would be from a 0 dBFS peak, where your RMS levels of most recordings are about 20 dBs below that. In real life, with non ideal gain structure, a 75 dB SINAD can mean quite audible noise and distortion in many use cases. But again that's not all, other stuff matters, the thing is we have all these measurments for the linear behaviour, more often than not at 1k, but it's rare to see measurments toward the limits, and rightfully so, Amir could break most of the devices he received. We tend to think that our device always operate in their optimal zone, but you'd be surprised how many peaks are clipped or compressed with micro-powered device with normal headphones. You'd be surprised to see some frequency response, or IMD graphs if they where taken at the limit of available power, or or with dynamic loads. We like to see margins, headroom, because they are used more often than we think. People sometimes refer to dynamic range of records of tape to assess that all those extra bits are pointless, but fail to recognize that in the analog days, there was no 105dB/mW IEMs, the calculations where simple, a room, speakers, environmental noise floor, dB SPL at listener position, easy to optimize gain structure. Now the use cases and type of transducers are all over the place, often great amount of digital attenuation, gain structure all over the place as well, and with portable device like this, heavily compromised power availability. So looking at a poor SINAD value and conclude that it's transparent anyway is bogus most of the time, it's only transparent in very specific optimal cases that rarely occurs
 
Last edited:

Ismapics

Active Member
Joined
Nov 21, 2020
Messages
159
Likes
201
Good point. This is the 9th generation. I updated the review.
Hello, no real audiophile uses these for DAP or ever uses the headphone jack. These are the best $50 remote controls you can get. I have 2 and use one as Spectrum Analyzer just for fun and the other runs the Receiver Software and Tv box software to control playback. In 2 years since I have never used to headphone jack.
 

Ismapics

Active Member
Joined
Nov 21, 2020
Messages
159
Likes
201
It is a great device for BT streaming on my desk or basement workshop systems. Cheap, easy to use. Is it audiophile? I dont care in those two situations because of high background noise levels. I still like Amirs tests on it.

I do the same. I take one to the garage when I wash my car and playback through portable BT Speakers. Rest of the time I use as remote control for my HT
 
Top Bottom