[CoiL]

For what stage? In what device?

Darn... totaaly forgot to add this...

Device is Aune T1 with capacitors mod and opamp I would like to try change is headphone amp board NE5532AD dual-channel opamp with swichable gain (+10db (~500mA) & +16db (~1000mA) ).

Though, in current setup with Siemens/Halske E88CC goldpin tube it sounds totally great. Just wondering if I could get more SQ out of HO.

 

[raoultrifan]

I assume the NE5532AD is used in gain-stage/voltage-amplification, so any audio opamp & unity-gain stable should do just well here: OPA1612, LME49720/LM4562, MUSES8820/8920/01/02, BURSON SS V6 etc. It would be interesting to find out the voltage rails, though given the output voltage I guess would be +/-12V.

 

[CoiL]

I assume the NE5532AD is used in gain-stage/voltage-amplification, so any audio opamp & unity-gain stable should do just well here: OPA1612, LME49720/LM4562, MUSES8820/8920/01/02, BURSON SS V6 etc. It would be interesting to find out the voltage rails, though given the output voltage I guess would be +/-12V.

Will measure it and report back. Anyway, powering the V5i-D was problem.

EDIT:

Measured between pin 4(V-) and pin8 (V+) with NE5532 and got 30.2V ! No load, 0 gain. Under load with music, same.
Should be real as power brick is with voltage swing 15V-0-15V.

I`m confused. Why didn`t V5i-D work? I installed it right way for sure.

 

[raoultrifan]

You're not the only one that found incompatible equipment for V5i-D. I got a similar issue when tried to roll it in my Matrix HPA-3B headamp. V5i is a great opamp, but it's just not compatible with everything out there, so we just need to live with this and swap it for a different opamp.

 

[CoiL]

Will try to re-solder V5i-D again... just to be sure I didn`t mess anything up and soldering points are great. Pity if it doesn`t work.

EDIT:

Btw, wanted to ask if installing 2x NE5534 with 2xSingle-to-1xdual adapter will provide SQ improvement over NE5532AP dual-channel chip ?

EDIT2:

Maybe NE5532 being bi-polar in Aune T1 is problem for V5i-D ?

Also, what do You guys say about changing Aune T1 DAC differential opamp which is OPA2134 if I remember correctly? Would it have any useful SQ improvement?

 

[yurt28]

Does anybody know how Max293CPA dippers work? I can't get these 8 pin dips to pass through anything without over heating.

 

[CoiL]

Device is Aune T1 with capacitors mod and opamp I would like to try change is headphone amp board NE5532AD dual-channel opamp with swichable gain (+10db (~500mA) & +16db (~1000mA) ).

Though, in current setup with Siemens/Halske E88CC goldpin tube it sounds totally great. Just wondering if I could get more SQ out of HO.

Ok, added those DIP8 dual-channel cheapo opamps in my shopping basket:

LM358N
NJM4560D
LM4562NA
LME49720NA

any of them that sounds total crap and should scrap off the list?

One more question - can I use ADA4084-2 in that location?
____________________________________________________________________________

EDIT:

Ok, since I`m not so experienced opamp-roller like most users in this thread seem to be, I`ll better ask some important questions than shoot off blindly into those cheap opamps:

What are THE MUST specifications (for example does it have to be bipolar? GBP must be 10MHz? RRIO is OK?) for an opamp in my case with Aune T1 headamp board implementation ?

Headamp board transistors are B649 / D669
Stock headamp board opamp is NE5532
headamp board has 3 different gain modes - +0dB / +10dB / +16dB
NE5532 measures between pin 4(V-) and pin8 (V+) 30.2V

I just thought that instead experimenting with cheapo opamps which probably give no SQ improvement, I rather buy something good with money I would spend on these.
So far I`m interested about these:

1) ADA4084-2ARZ-R7
https://eu.mouser.com/ProductDetail/Analog-Devices/ADA4084-2ARZ-R7?qs=BpaRKvA4VqECXiuuCyMa3A==

2) AD8599ARZ
https://eu.mouser.com/ProductDetail/Analog-Devices/AD8599ARZ?qs=sGAEpiMZZMvtNjJQt4UgLalm6EXZly/yucPtlNMTDKM=

3) ADA4004-2ARZ
https://eu.mouser.com/ProductDetail/Analog-Devices/ADA4004-2ARZ?qs=sGAEpiMZZMvtNjJQt4UgLalm6EXZly/yp89fjq9heu8=

4) AD8676ARZ
https://eu.mouser.com/ProductDetail/Analog-Devices/AD8676ARZ?qs=sGAEpiMZZMvtNjJQt4UgLalm6EXZly/yBkniS4BODf0=

5) AD8672ARZ
https://eu.mouser.com/ProductDetail/Analog-Devices/AD8672ARZ?qs=sGAEpiMZZMvtNjJQt4UgLalm6EXZly/y8vNj%2bbcMPN0=


...don`t slap me please

 

[raoultrifan]

[...]
Btw, wanted to ask if installing 2x NE5534 with 2xSingle-to-1xdual adapter will provide SQ improvement over NE5532AP dual-channel chip ?

Crosstalk might be better, so soundstage could increase, but only theoretically, because today's opamps already have an extremely good channel separation by default (our ears are very comfortable with a channel sepparation of 70dB for freqs. lower than 10KHz and >50dB for freqs. higher than 10KHz).

[...]
Maybe NE5532 being bi-polar in Aune T1 is problem for V5i-D ?

Don't think it matters. You should leave with the fact that V5i-D is incompatible with Aune T1.

[...]
Also, what do You guys say about changing Aune T1 DAC differential opamp which is OPA2134 if I remember correctly? Would it have any useful SQ improvement?

You should post a layout of something here...sort of a schematic. Where is this OPA2134 located? Is it in I/V stage?
Try a MUSES8920 instead or an OPA1612.

 

[CoiL]

Thanks for advice. I think Iwill leave dac differential opamp as it is for now and try to improve headamp board.
Atm I need advice if those opamps are compatible instead NE5532 in that application:

Headamp board transistors are B649 / D669
Stock headamp board opamp is NE5532
headamp board has 3 different gain modes - +0dB / +10dB / +16dB
NE5532 measures between pin 4(V-) and pin8 (V+) 30.2V

1) ADA4084-2ARZ-R7
https://eu.mouser.com/ProductDetail/Analog-Devices/ADA4084-2ARZ-R7?qs=BpaRKvA4VqECXiuuCyMa3A==

2) AD8599ARZ
https://eu.mouser.com/ProductDetail/Analog-Devices/AD8599ARZ?qs=sGAEpiMZZMvtNjJQt4UgLalm6EXZly/yucPtlNMTDKM=

3) ADA4004-2ARZ
https://eu.mouser.com/ProductDetail/Analog-Devices/ADA4004-2ARZ?qs=sGAEpiMZZMvtNjJQt4UgLalm6EXZly/yp89fjq9heu8=

4) AD8676ARZ
https://eu.mouser.com/ProductDetail/Analog-Devices/AD8676ARZ?qs=sGAEpiMZZMvtNjJQt4UgLalm6EXZly/yBkniS4BODf0=

5) AD8672ARZ
https://eu.mouser.com/ProductDetail/Analog-Devices/AD8672ARZ?qs=sGAEpiMZZMvtNjJQt4UgLalm6EXZly/y8vNj%2bbcMPN0=

 

[FritzS]

NE/SA/SE5534 - in old schemas there gives an trick to give them more BIAS in output driver. As far as I know a resistor to pin_5 (8, 1), but I don't found any hints in Internet.
I saw this in a DIY schematic a long time ago, but can't find this DIY magazine anymore.

http://www.onsemi.com/PowerSolutions/product.do?id=NE5534

 

[CoiL]

I made a little specs comparison table:

Which ones to choose?
AD8672ARZ & AD8676ARZ both seem promising by specs and should work... or not?
Previously recommended OPA1612 looks nice too but higher slew rate & 80MHz make it questionable for me...

 

[raoultrifan]

Please review the datasheet, in some places voltage rails are having +/- in font. Also, AD8599 can be powered from +/-15V with an absolut max. of +/-18V.

AD8599 surclasses the AD8672; it can also be used in I/V stage with great results, I did it in PLAY and it was perfect match (also, see Vaughan DAC).

OPA1612 is great too, it doesn’t oscillate if PCB design is right and decoupled according datasheet.

 

[CoiL]

So, You`re saying I should just go for AD8599 instead of buying&trying AD8672 / AD8676 / ADA4084 ?
Any idea about AD8599 output current per channel? Couldn`t find it...

 

[raoultrifan]

They’re not expensive, give’em all a try, later you’ll decide which one’s the winner.

You could also try 2xAD797 with single-dual adapters, they’re the less noisiest from this group.

 

[CoiL]

Ok, decided & bought AD8599ARZ first to try... will report back soon. Hope I don`t run into any issues like with V5i-D.