Hi there.
Have an old D/A kit (AIDA from the danish magazine High-fidelity) i want to bring back from the dead.
It uses 2 pcs of ad846 which i sold a long time ago. This opamp is no longer made, so which can i use instead directly without any mods?? any advise would be appriciated, thanks 😀
Or should anyone have 2 they no longer need, id be happy to buy them.
/Per
Have an old D/A kit (AIDA from the danish magazine High-fidelity) i want to bring back from the dead.
It uses 2 pcs of ad846 which i sold a long time ago. This opamp is no longer made, so which can i use instead directly without any mods?? any advise would be appriciated, thanks 😀
Or should anyone have 2 they no longer need, id be happy to buy them.
/Per
According to Analog this is a direct replacement:
http://www.analog.com/en/prod/0,2877,AD846,00.html
http://www.analog.com/en/prod/0,2877,AD811,00.html
http://www.analog.com/en/prod/0,2877,AD846,00.html
http://www.analog.com/en/prod/0,2877,AD811,00.html
if you have a little patience, LME49713's are trickling out of National Semiconductor at a snail's pace. This is a CFB opamp designed specifically for audio.
I found some of the LME49713 -- they are SOIC so you will need an adapter if replacing a DIP. PM me if you care.
LME49713
Has anyone experience with this opamp? How does it sound?
I'm looking for an alternative in my preamp for second stage to replace my LM4652 which isn't so bad!
The 49713 needs a low input impedance about 2k so ordinary 10k log pots won't work!?
Regards
Thomas
Has anyone experience with this opamp? How does it sound?
I'm looking for an alternative in my preamp for second stage to replace my LM4652 which isn't so bad!
The 49713 needs a low input impedance about 2k so ordinary 10k log pots won't work!?
Regards
Thomas
The non-inverting input impedance is 1.2 meg Ohms -- inverting is 50 -- you have to be very selective in choice of the feedback and gain resistors, The device will drive a 150 ohm load.
Remember that this is an SMT device.
Remember that this is an SMT device.
Re: LME49713
... and the max impedance seen from a 10k pot wiper is 2.5k, so not that bad anyway.
Jan Didden
Tolu said:
... and the max impedance seen from a 10k pot wiper is 2.5k, so not that bad anyway.
Jan Didden
Hi.
Has anyone tried the NS LME49710, which is available in both packages. I would be interested in any thoughts or comparisons that may have been done.
Regards
Gary..
Has anyone tried the NS LME49710, which is available in both packages. I would be interested in any thoughts or comparisons that may have been done.
Regards
Gary..
The AD811 is also very worthwhile! I used them to replace the IV opamps in my CD-player, and they are very nice. I only had to put a 1K resistor on the input to get them stable.
gary s said:
Hi Gary
I am using the 2-channel-version LM4562NA in a KR Audio Electronics P150 preamp which had replaced the built-in OPA2134. They are very very good if you like a clean, rich and detailed sound with no lack in any frequency band. Bass is deep and well controlled, highs are detailed and nearly perfect, mids are very euphonic.
Very important: you need two stages otherwise sound is a little bit thin.
The OPA2134 is great two but a little bit more laid back and not so detailed but not that bad anyway. An interesting solution was OPA2134 for first stage and LM4562 for second (output) stage.
At the moment I see no need for a discrete solution.
Regards
Thomas
Re: LME49713
This opamp is a current feedback design. The feedback resistor is determined by looking at the curves for the device. The best resistor is about 1.2k.
Therefore, the shunt resistor (resistor to ground) is very low-for a gain of ten it would be 120 ohms.
The gain would not be 11 though-it's ten-because the non inverting imput is simply an inverting buffer whose output is tied to the - input.
Normally, you do not feed any signals into the -input. All audio goes in through the + input, which has an input impedance of about 1.2 megohms.
Tolu said:
This opamp is a current feedback design. The feedback resistor is determined by looking at the curves for the device. The best resistor is about 1.2k.
Therefore, the shunt resistor (resistor to ground) is very low-for a gain of ten it would be 120 ohms.
The gain would not be 11 though-it's ten-because the non inverting imput is simply an inverting buffer whose output is tied to the - input.
Normally, you do not feed any signals into the -input. All audio goes in through the + input, which has an input impedance of about 1.2 megohms.
Vasestar,
Maybe this post is long time dear, but I have not seen it before now... .
To get your AIDA up running as original - I would love to donate you a few AD846 current op-amp's. This AIDA construction was from the 'golden days' of the magazine.
Just contact me if you still need them 🙂
Maybe this post is long time dear, but I have not seen it before now... .
To get your AIDA up running as original - I would love to donate you a few AD846 current op-amp's. This AIDA construction was from the 'golden days' of the magazine.
Just contact me if you still need them 🙂
The AD846 is a great sounding opamp!
This may be simply because it is a CFB type.
I have some of these that I'm considering selling
only because I don't need them anymore.
This may be simply because it is a CFB type.
I have some of these that I'm considering selling
only because I don't need them anymore.
Well i fired it up and it didn't work. Alot of noise and hum. So back to the workshop shelves with it 😀 Not gonna waste more time on it.
So thanks for offering .!!!
So thanks for offering .!!!
Vasestar, Just come back to me if you need these op-amp's in the future. My offer in valid a few years more 😉