I hate experimenting with opamps
well, not really, I do it all the time, but it is a royal PITA to unsolder through-hole devices, and sockets just lead to sub-par results<p> Here's a tip -- use the "dead-bug" methodology. Mount the device on its back on the reverse side of the board. Bend the pins backwards to fit the traces and solder. I first saw the technique described in an application note from Analog Devices. It's a good technique for mounting the older switching chips since you can make the lead length very short.<p>For removing smt devices one technique I have seen is to use a small piece of wirewrap wire, slip it under the pins and heat. (Of course, you should be using needle-nose to hold the wire unless your fingers are very caloused!) You can gently pry smt chips off the board this way.
well, not really, I do it all the time, but it is a royal PITA to unsolder through-hole devices, and sockets just lead to sub-par results<p> Here's a tip -- use the "dead-bug" methodology. Mount the device on its back on the reverse side of the board. Bend the pins backwards to fit the traces and solder. I first saw the technique described in an application note from Analog Devices. It's a good technique for mounting the older switching chips since you can make the lead length very short.<p>For removing smt devices one technique I have seen is to use a small piece of wirewrap wire, slip it under the pins and heat. (Of course, you should be using needle-nose to hold the wire unless your fingers are very caloused!) You can gently pry smt chips off the board this way.
Jean-Paul,
"It is nice to discuss theory..."
Surely it is _essential_ to consider the theory before making any modifications.
"NE5532 is ancient and so is the sound it produces."
The design of this device may well be old, but it provides a very good sound at a low price. The opamps mentioned should represent a sonic upgrade - it may or may not be worthwhile in this situation.
Anyway, Paul, have fun and be careful,
Tim.
"It is nice to discuss theory..."
Surely it is _essential_ to consider the theory before making any modifications.
"NE5532 is ancient and so is the sound it produces."
The design of this device may well be old, but it provides a very good sound at a low price. The opamps mentioned should represent a sonic upgrade - it may or may not be worthwhile in this situation.
Anyway, Paul, have fun and be careful,
Tim.
Ok, maybe I wont use sockets.
-I have pretty good soldering skills, i guess this will put them to the test. I will just have to figure out a way to listen to it without having to put the whole thing back together again.
BTW, could any of you reccomend a good single disk player that has good modding ability that can be found for cheap?
-Paul Hilgeman
-I have pretty good soldering skills, i guess this will put them to the test. I will just have to figure out a way to listen to it without having to put the whole thing back together again.
BTW, could any of you reccomend a good single disk player that has good modding ability that can be found for cheap?
-Paul Hilgeman
Halojoy - not quite correct
If you can't hear the difference, then why do manufacturers like AMP, Molex, Thomas & Betts go to such great lengths to manufacture sockets with gold plating, machined pins etc.<p>I realize that we are talking opamps on this thread, but I often work with ADC's and DAC's -- and know from experience that you want the device such as these to be as flat to the ground plane as possible, you want the ground planes for digital and analog to be separate, you want the decoupling cap lead length to be as short as possible, etc. <p>I wonder if you could hear the difference in a moving coil amp between a socketed and non-socketed device.
If you can't hear the difference, then why do manufacturers like AMP, Molex, Thomas & Betts go to such great lengths to manufacture sockets with gold plating, machined pins etc.<p>I realize that we are talking opamps on this thread, but I often work with ADC's and DAC's -- and know from experience that you want the device such as these to be as flat to the ground plane as possible, you want the ground planes for digital and analog to be separate, you want the decoupling cap lead length to be as short as possible, etc. <p>I wonder if you could hear the difference in a moving coil amp between a socketed and non-socketed device.
jean-paul said:
Agree totally! I used long time ago common sockets with only one contact spring. After a couple of years the amp started to get awfully noisy with a very unregular, uneven noise, like popconoise but not. The opamps had also moved out from the sockets! My advise is to use only goldplated "tulip" contact sockets for development and then if possible remove them when the development is over but only if you can desolder them without damaging the pcb. If you have fast opamps it's often essential to have short legs (near decoupling caps) and the chip near the groundplane (pcb).
How bad is it to solder the opamps in their sockets? I mean, if sockets do not ruin the sound at start, so not in case of the fast opamps Per was talking about. You can have the benefit of easy experimenting with different opamps and once you found the best you solder them in so that you'll not be bothered by bad contacts after a few years. Your PCB will not be damaged.
Dead-bug method: Nice tip jackinnj!
Dead-bug method: Nice tip jackinnj!
Dre, I guess a technique like that is a compromise and most audiophiles don't like that. It's sockets or soldering direct. PCB won't get damaged when you use litze wire for desoldering.
Agreed, nowadays produced "green" PCB material is venerable.
Anyone who modifies or repairs the newer Sony stuff will know what I mean.
Agreed, nowadays produced "green" PCB material is venerable.
Anyone who modifies or repairs the newer Sony stuff will know what I mean.
jean-paul said:
Agreed. I think a true audiophile will NEVER use sockets, though.
It just seemed a better solution than using gold plated sockets as they do not stop the leads from the opamp from corroding which ruins the contact. Furthermore I wondered if anyone has actually tried it so that (s)he could tell me the difference in sound quality.
This isn´t exactly the right thread i believe.
But i wonder why no one ever talks about the AD826 for
dual OPs. I switched a lot OPs into the output buffer
of my DAC (earlier thread somewhere) and ended up
with an AD826. It is the only fast Analog Devices with
the ability of +/- 15V i can buy here. So i had no chance
to compare against the AD8620.
I have to admit that you have to be careful with the
layout cause of its high bandwith. A digital TV
receiver next to it even stopped working when i pulled
the power switch of the DAC
until i soldered a
capacitor cross the voltage pins.
It produces a very unspectacular sound with wonderfull
resolution and the touch it needs to sound musically.
Neither synthetic nor agressive or bloated.
Short: I love it
Oh, another thing.
During testing i have collected different 5532s.
LRAY, Philips and Ti
The LRAY sounds harsh and the Ti plugged.
The only good one is the Philips that does everything
right but misses the resolution that faster ones can
archive.
All listening just for my DAC.
Has anybody similar experiences, or should i dung my in-ear
parsley more often?
But i wonder why no one ever talks about the AD826 for
dual OPs. I switched a lot OPs into the output buffer
of my DAC (earlier thread somewhere) and ended up
with an AD826. It is the only fast Analog Devices with
the ability of +/- 15V i can buy here. So i had no chance
to compare against the AD8620.
I have to admit that you have to be careful with the
layout cause of its high bandwith. A digital TV
receiver next to it even stopped working when i pulled
the power switch of the DAC
until i soldered a capacitor cross the voltage pins.
It produces a very unspectacular sound with wonderfull
resolution and the touch it needs to sound musically.
Neither synthetic nor agressive or bloated.
Short: I love it
Oh, another thing.
During testing i have collected different 5532s.
LRAY, Philips and Ti
The LRAY sounds harsh and the Ti plugged.
The only good one is the Philips that does everything
right but misses the resolution that faster ones can
archive.
All listening just for my DAC.
Has anybody similar experiences, or should i dung my in-ear
parsley more often?
PaulHilgeman said:
I'm not particulary for weird tweaks but changing NE5532 to OPA2134, 2604 is a technical not so weird tweak. These chips are better but you can also get unpredictable results because of the facts that they are JFET types and 5532 is BJT. You can also get unwanted results because they are faster. RF-emission is transfered trough the chip in a higher degree, maybe...
My advise is to go for it but see to that it's possible to move the old chips back. Also, add decoupling caps (10-100 nF ceramic), can't hurt.
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