• 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!

AIYIMA A07 TPA3255 Review (Amplifier)

tonycollinet

Major Contributor
Forum Donor
Joined
Sep 4, 2021
Messages
2,217
Likes
3,172
Location
UK/Cheshire
I'm sure I'm asking a noob question but I got to do what I got to do... Is it possible to add a sub to this amp? I'm willing to power kef r3 and sb1000 pro
Yes, but it doesn't have a sub output. So you'd need to split the source RCA signals to get a signal to the sub, or (better probably) get a sub with high level inputs and then connect it to the speaker terminals. Looks like the SB1000 pro does have the high level inputs.
 

RHO

Major Contributor
Joined
Nov 20, 2020
Messages
1,066
Likes
925
Location
Belgium
Yes, but it doesn't have a sub output. So you'd need to split the source RCA signals to get a signal to the sub, or (better probably) get a sub with high level inputs and then connect it to the speaker terminals. Looks like the SB1000 pro does have the high level inputs.
There is a 3.5mm stereo output/input on the back of the amp. You could use that to connect a sub.
 

nsfgp

Member
Joined
Dec 27, 2020
Messages
60
Likes
39
There is a 3.5mm stereo output/input on the back of the amp. You could use that to connect a sub.
Doesn't hurt to remind again that the A07 3.5mm output/input jack has the L/R channel reversed compared to the RCA input. So deal with it accordingly if/as needed.
 

tonycollinet

Major Contributor
Forum Donor
Joined
Sep 4, 2021
Messages
2,217
Likes
3,172
Location
UK/Cheshire
Doesn't hurt to remind again that the A07 3.5mm output/input jack has the L/R channel reversed compared to the RCA input. So deal with it accordingly if/as needed.
Probably unimportant for a sub - especially a single sub.
 

Toku

Major Contributor
Joined
Apr 4, 2018
Messages
1,652
Likes
1,659
Location
Japan
Probably unimportant for a sub - especially a single sub.
No, since it is output in the full range from A07, it is mixed with the sub output and the opposite phase greatly affects the sound.
I found the 3.5mm anti-phase problem early and reported it to AIYIMA. But they didn't accept my report saying they were right.
 

tonycollinet

Major Contributor
Forum Donor
Joined
Sep 4, 2021
Messages
2,217
Likes
3,172
Location
UK/Cheshire
No, since it is output in the full range from A07, it is mixed with the sub output and the opposite phase greatly affects the sound.
I found the 3.5mm anti-phase problem early and reported it to AIYIMA. But they didn't accept my report saying they were right.
He said the LR Channel reversed, not that it was antiphase.
 

nagster

Active Member
Joined
Jan 24, 2021
Messages
243
Likes
378
The image is a scope shot of the tip of the AUX3.5mm jack when the generator output is input to the RCA Lch of the A07.
aiyima_a07_scope01.jpg
 

nsfgp

Member
Joined
Dec 27, 2020
Messages
60
Likes
39
Thank you Nagster. Does your testing means for your A07 => RCA input signal when looped for concurrent output thru the 3.5mm jack does NOT have the L/R channel reversed??
When you feed INPUT into the 3.5MM jack does the speaker channel L/R output got reversed?? (Compared to using RCA input)

My A07 is packed up for storage now but at least I can recall when using the 3.5mm jack as INPUT => the L/R channel speaker out is reversed when compared to RCA input. And I can confirm the cable are industry standard (3.5mm TRS tip goes to white rca tip for L channel).
I did not try using the 3.5mm jack as concurrent loop-back output for the RCA input signal though. I just assumed it will be reversed as well in that situation. It seems very interesting if I am wrong here seeing your test. Very curious.
 

nagster

Active Member
Joined
Jan 24, 2021
Messages
243
Likes
378
Thank you Nagster. Does your testing means for your A07 => RCA input signal when looped for concurrent output thru the 3.5mm jack does NOT have the L/R channel reversed??
When you feed INPUT into the 3.5MM jack does the speaker channel L/R output got reversed?? (Compared to using RCA input)

My A07 is packed up for storage now but at least I can recall when using the 3.5mm jack as INPUT => the L/R channel speaker out is reversed when compared to RCA input. And I can confirm the cable are industry standard (3.5mm TRS tip goes to white rca tip for L channel).
I did not try using the 3.5mm jack as concurrent loop-back output for the RCA input signal though. I just assumed it will be reversed as well in that situation. It seems very interesting if I am wrong here seeing your test. Very curious.
I don't know if I understand your post. I am bad at English. I hope the image will be helpful.
This time the generator output was connected to the A07's 3.5mm jack.
By the way, my A07 was purchased from Amazon in May this year. The serial number was not found.
aiyima_a07_scope_11.jpg
 

Attachments

  • aiyima_a07_scope_12.jpg
    aiyima_a07_scope_12.jpg
    110.2 KB · Views: 24
  • aiyima_a07_scope_13.jpg
    aiyima_a07_scope_13.jpg
    108.2 KB · Views: 23
  • aiyima_a07_scope_14.jpg
    aiyima_a07_scope_14.jpg
    104.4 KB · Views: 22
  • aiyima_a07_scope_15.jpg
    aiyima_a07_scope_15.jpg
    107.7 KB · Views: 24
  • 3p5-rca_01.jpg
    3p5-rca_01.jpg
    94.3 KB · Views: 23
  • 3p5-rca_02.jpg
    3p5-rca_02.jpg
    92.6 KB · Views: 23

nsfgp

Member
Joined
Dec 27, 2020
Messages
60
Likes
39
Thank you Nagster ... you are a wonderful asset to ASR ... always willing to help and do extra when asked.
Yes your A07 has the reversed channel issue of the 3.5mm jack fixed!! So looks like new units at least after May, 22 from Amazon should expect to have the fix in place.
I will be damned ... Aiyima finally fixed it after so long ... better late than never I guess. Good stuff.
 

nsfgp

Member
Joined
Dec 27, 2020
Messages
60
Likes
39
While you are at it few more questions. For your May22 A07:
1. Does the volume pot seems to be linear pot(old) or log pot (what should have been used from the start)
2. Do you notice reduced input sensitivity or power (may only notice if you have used older A07 that actually shown differences in these area)?
3. When you have a chance can you post some internal pics of your May22 Amazon A07??

Q#2 is because I brought one of the last A04 too right before they disappeared from Amazon (at a much reduced price too if that matters). And it has very low input sensitivity and/or reduced power which many people already reported/complained about. Aiyima added PFFB for those A04 and noise is greatly reduced but with much lower input sensitivity. Wonder if they did similar tricks to newer A07 while they were fixing the 3.5mm jack issue.
Thank you!!
 

Zek

Addicted to Fun and Learning
Joined
Feb 17, 2018
Messages
937
Likes
1,330
And I can confirm the cable are industry standard (3.5mm TRS tip goes to white rca tip for L channel).
Yes, you are right.
If you have a multimeter, you can check how the 3.5mm connector is connected to the RCA connectors on A07.
 

nagster

Active Member
Joined
Jan 24, 2021
Messages
243
Likes
378
Voltage gain vs. volume position graph, Level sweep graph and Internal photo.
aiyima_a07_gain_03.png
 

Attachments

  • aiyima_a07_thdn_gen_02.png
    aiyima_a07_thdn_gen_02.png
    86.6 KB · Views: 36
  • aiyima_a07_thdn_meas_02.png
    aiyima_a07_thdn_meas_02.png
    94.4 KB · Views: 58
  • aiyima_a07_21.jpg
    aiyima_a07_21.jpg
    357.4 KB · Views: 59
  • aiyima_a07_level_00.png
    aiyima_a07_level_00.png
    41.4 KB · Views: 49
Last edited:

tvih

Active Member
Joined
Nov 9, 2020
Messages
159
Likes
113
Welp, looks like I ended up ordering one. Wasn't planning on it but needed to order another device to drive an old DIY sub, so snagged it at the same time to "split" the postage. Technically it's to drive my surround speakers for equipment chain gain staging purposes, but who knows, might end up using it for the fronts... at least it should have a better SINAD than the current one, and slightly more wattage. Probably gonna sound the same anyway, though.
 

Toku

Major Contributor
Joined
Apr 4, 2018
Messages
1,652
Likes
1,659
Location
Japan
What you mean ”anti-phase” - only left and right channel are swapped, what does that have to do with phase?
sorry! I seem to have posted something wrong. Please ignore.
 
Top Bottom