Its not particularly new but ADA4625-2 beats 1656 on noise at frequencies below 3kHz.
ADA4625-X has excellent specs indeed, better than ADA4627-X, so very tempting. And then comparing both just listening to music during a shootout in a very simple test rig (adding them in the loop merely in a non demanding application to see their potential sonic signature) a couple of years ago, I found ADA4627-X better sounding on nearly all aspects.
That one was very very good, but then again beaten slightly overall by OPA1656... to my ears. Of course depending on application that could be different, some OP amps not even running or suited! Plus you may want to alter slightly your sonic signature and use Ad's tremendous speed (I was always an AD fan).
For more details on this shootout please use advanced search function, I posted quite in length back then and there was also my long time favourite AD825 biased in Class A with 2SK170 (overkill bit 20y ago it was cheap LOL).
As long as OPA1656 is used within its application field, and musical flow and neutrality are key (eg one is not trying to colour the music, suggering or drying it), OPA1656 does indeed an excellent job that is difficult to beat (provided proper PS as ever). Of course I would be delighted to find a new king, so open to suggestions!
All IMHO / I hope it helps
Have fun
Claude
That one was very very good, but then again beaten slightly overall by OPA1656... to my ears. Of course depending on application that could be different, some OP amps not even running or suited! Plus you may want to alter slightly your sonic signature and use Ad's tremendous speed (I was always an AD fan).
For more details on this shootout please use advanced search function, I posted quite in length back then and there was also my long time favourite AD825 biased in Class A with 2SK170 (overkill bit 20y ago it was cheap LOL).
As long as OPA1656 is used within its application field, and musical flow and neutrality are key (eg one is not trying to colour the music, suggering or drying it), OPA1656 does indeed an excellent job that is difficult to beat (provided proper PS as ever). Of course I would be delighted to find a new king, so open to suggestions!
All IMHO / I hope it helps
Have fun
Claude
On the right is the opamp from the same seller (aliexpress) and it sounds very nice, like opa1656.
I haven't checked this on the left, but this is the second order from the same seller.
I haven't checked this on the left, but this is the second order from the same seller.
I can not see why anyone would go through the bother of putting a fake part in a sealed tape format. Look at the TI spec, they show info on the part marking scheme. Looks genuine, if not doing a damn good job at making fakes. There are a few simple tests to verify it’s real.
I do wonder how these parts get into Russia however, I thought the country is sanctioned. Oh, now that I think about it some more, Russia is in tight with China and China don’t care about sanctions, so ask your China source if they are real or they are stealing your $.
I do wonder how these parts get into Russia however, I thought the country is sanctioned. Oh, now that I think about it some more, Russia is in tight with China and China don’t care about sanctions, so ask your China source if they are real or they are stealing your $.
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These graphs show have different scales. Lower one goes to 100k top to 100mhz. Look very similar in the same range.
I have a need for an instrumentation amplifier with fully differential output.
I want to do better than INA851 in terms of THD+N.
Should I be using 2x OPA1656 + 1x OPA1633 to make it from scratch ?
Any better / simpler suggestions ?
Thanks in advance,
Patrick
I want to do better than INA851 in terms of THD+N.
Should I be using 2x OPA1656 + 1x OPA1633 to make it from scratch ?
Any better / simpler suggestions ?
Thanks in advance,
Patrick
If you accept almost 2 orders of magnitude higher distortion, maybe.
And there are supposed to be better ways to couple them.
https://www.analog.com/en/analog-dialogue/raqs/raq-issue-161.html
Cheers,
Patrick
And there are supposed to be better ways to couple them.
https://www.analog.com/en/analog-dialogue/raqs/raq-issue-161.html
Cheers,
Patrick
What exactly is wrong with the INA851.
THD in the 1 digit ppm range, fantastic specs all over, will be hard to beat with separate opamps.
Hans
THD in the 1 digit ppm range, fantastic specs all over, will be hard to beat with separate opamps.
Hans
Both OPA1656 and OPA1633 are below -130dB.
2nd and 3rd harmonics at -150dB or below.
Cheers,
Patrick
2nd and 3rd harmonics at -150dB or below.
Cheers,
Patrick
I´m afraid the specs make it a bit difficult to compare.
When both amps at Vout=3.5Vrms, Gain=1 and Load=2k
The INA851 specifies THD+N at -110dB @ 10Khz and at a BW of 500Khz.
The OPA1656 specifies THD+N at -130dB @ 10Khz and a BW of 80Khz, why is that, how does the spectrum look beyond 80Khz ?
Also take into account that when using three opamps, distortion will increase accordingly.
I would be surprised when the INA851 can't match it.
Hans
When both amps at Vout=3.5Vrms, Gain=1 and Load=2k
The INA851 specifies THD+N at -110dB @ 10Khz and at a BW of 500Khz.
The OPA1656 specifies THD+N at -130dB @ 10Khz and a BW of 80Khz, why is that, how does the spectrum look beyond 80Khz ?
Also take into account that when using three opamps, distortion will increase accordingly.
I would be surprised when the INA851 can't match it.
Hans
Attachments
So, when you’re already convinced it’s a better solution, why asking ?
Better in THD doesn’t exist with opamps and you have rejected simpler.
Hans
Better in THD doesn’t exist with opamps and you have rejected simpler.
Hans