Aiyima A07/ A07 Max OP Amps The Same?

[ICIETDIYEUR]

People hi

Concerning the AIYIMA A07 MAX amplifier and after observing its diagram we can already see that the values surrounding the OpAmps are high (10K).
If we refer to TI's advice, it is preferable in this case to use FET or JFET type OpAmps rather than BIPOLAR ->

If I do not wish to express myself in "subjective" words to talk about improving the "quality of the sound" reproduction, it will be easy in an "objective" way, for the present case, to interpret the results obtained by using the formula in the table to note an improvement... so normally perceptible to the listener...

Some OpAmps references such as the OPA1656, OPA828 or OPA1642 (there are others) are available from TI and are perfectly suited to the circuit of this amplifier.
I have my preference for one of these three references because I hear it but maybe others won't hear it ?

In any case, it has been a long time now that the distortion values of OpAmps are no longer perceptible to the ear but only with the help of measuring devices: who today could say the opposite and especially dismantle it ?

I'll be nice to choose on these three OpAmps:
- it is the one that costs the least
- it is the only one whose DATASHEET uses the term "Broadcast Studio Equipment".

Happy listening to all

PS: leave aside the 'discreet' OpAmps because the only reduction they are able to bring you is the balance of your bank account but certainly not the distortion of your device! Look at their DATASHEET (if provided...) or better yet: measure them

 

[bramsat]

The best opamp is the phillips NE5532n and not the OPA 1656 the phillips sounds match better....on the A07 original, and lesser on the A07 MAX.

https://nl.aliexpress.com/item/1005003071748273.html?spm=a2g0o.order_list.order_list_main.16.35f079d2PthIYz&gatewayAdapt=glo2nld

 

[ICIETDIYEUR]

Hello bramsat.

The AIYIMA A07 has the same input circuit as the AIYIMA 07 MAX: the signal that will be reproduced by it will be amplified by the TPA 3255.
Since the NE5532 is not only not adapted to the circuit topology and that it also has much worse characteristics than the OPA 1656 (by far):
this will result in more "miscellaneous" distortions...
... But are these pleasant for your ears ?

Be a little objective and provide us with measurements or another "way" that can be demonstrated to argue your words please.

Kind regards

 

[bramsat]

I've have 3 clas d amps the A07,the A07 max and the brzhifi with te XLR output they all sounds different with the same opamp...
dac: topping E50,LPS A32va,and 4 cdplayers.

 

[ICIETDIYEUR]

Good evening bramsat
I wouldn't question that they all sound different with the same op-amp...
... But do they "sound right" ?

So and at the risk of repeating myself:
In order to be objective, are you able to provide measurements or another "way" that can be demonstrated to argue your answer ?

Kind regards

 

[ICIETDIYEUR]

Let's have a look in the AIYIMA A07 MAX ->

And now ->

Note -> NE5532 is a BIPOLAR OpAmp (Wikipedia)

The tables show the Voltage-NOISE Density: The term Noise certainly does not mean music

 

[melomane13]

I feel the same but people swear there is night and day difference. I think the “upgrade” bug hit me along with tempting holiday sales

people swear earth is flat

 

[gwing]

people swear earth is flat

But, as this is ASR, it probably does measure flat, within visually distinguishable limits

 

[bramsat]

Good evening bramsat
I wouldn't question that they all sound different with the same op-amp...
... But do they "sound right" ?

So and at the risk of repeating myself:
In order to be objective, are you able to provide measurements or another "way" that can be demonstrated to argue your answer ?

Kind regards

After 6 mnd, my ears tels me that the phillips opamp is the best..for all the 3 classD amps,the brzhifi is for me the number2 he sounds more analytisch.
All 3 3255 chip amps are barcains,the reference for me are the accuphase E203 the akai ma 2650 but they al sounds the same as the classD amps!
Class AB amps are the best between 1978 and ± 1982. all klass AB amps after ±1984 inside europa market with FTZ or CE sounds bad and yes also the accuphase E240 E250 etc..
gr Abraham

 

[BDWoody]

I'd love to see the results of these comparisons with some meaningful controls, instead of it just being shared story time...

 

[antcollinet]

But, as this is ASR, it probably does measure flat, within visually distinguishable limits

No, it is quite possible to see the curvature of the earth - even at ground level. Go up a few miles in a plane, and it is ... err..... plain