I was looking for a header for the SOIC to DIP adapter cards
SparkFun SOIC to DIP Adapter - 8-Pin - BOB-13655 - SparkFun Electronics
that fits the sockets I have on my IPS7 daughter boards. Experience has taught me that just any old header will not do. All the square pin headers I've come across so far have pins that are .025" square. That's far too large for the socket I'm using. It's just another lesson learned.
Regards,
Dan
I did the power side swap a long time ago and it didn't matter to the ripple noise .
I rearranged all AC and transformer connections. I got rid of the cover on the power transformer (it did not work for me). I made a band on the toroid from the mumetel sheet that was left to me. Ripples of 100hz can be heard on the headphones and speakers .On the left channel it is quieter. The ARTA measurement and the smartphone application confirm this: the difference is about 3dB. I have no idea what to do with it so I have to ignore it.
Photos are ARTA for 1W / 8R dummy load.
Regards
Darek
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Hi. 4 months ago I was writing about the problems I had with one of the Tucson cards: high noise floor (#4210).
A few days ago I finally found time to look into it and noticed that both zeners show short circuit both ways! So the opamp OPA1611 saw full rails voltage of +-21.6V instead of +-10.
I changed the zeners first, but the problem remained, so OPA1611, being rated at max 40Vpp, did got damaged by 43.2Vpp. With the new opamp everything is fine.
I just wonder, what could be the cause of the damage to zeners? Could they be damaged before I installed them? Are they so sensitive to the static? I did not notice any static discharges while handling them and the new zeners that I put in were from the same batch in my Mouser order.
Could zeners were damaged by some overcurrent or something while in use in the amp? Can this happen again?
A few days ago I finally found time to look into it and noticed that both zeners show short circuit both ways! So the opamp OPA1611 saw full rails voltage of +-21.6V instead of +-10.
I changed the zeners first, but the problem remained, so OPA1611, being rated at max 40Vpp, did got damaged by 43.2Vpp. With the new opamp everything is fine.
I just wonder, what could be the cause of the damage to zeners? Could they be damaged before I installed them? Are they so sensitive to the static? I did not notice any static discharges while handling them and the new zeners that I put in were from the same batch in my Mouser order.
Could zeners were damaged by some overcurrent or something while in use in the amp? Can this happen again?
Since they were purchased from Mouser we can eliminate "counterfeit, low quality parts" as an explanation.
Since the other identical parts in the same Mouser bag worked perfectly, we can eliminate "dead even before stuffed and soldered" as an explanation. Only one Tucson board was affected; the other diodes on the other board were fine, AND the not-yet-used parts in the bag were fine.
That leaves "destroyed during board assembly" as a possibility. Too hot for too long during soldering. ESD damage (to two different parts!!??) during assembly. Too much tension / compression / torque during lead bending. Those kinds of assembly failures.
It also leaves "destroyed during amplifier power-up" as a possibility. Perhaps your PSU was not quite correct the first time(s) you powered up your Tucsons, and managed to fry some of the components on a daughter board.
It also leaves "destroyed during amplifier testing and listening" as a possibility. Perhaps you accidentally touched two of the mounting bolts at the same time, with something conductive: screwdriver, wrench, watch band, wire, chassis lid, etc. Perhaps this conductor managed to create a temporary short circuit which fried some of the components on the daughter board.
Observe that nothing written above, is specific to Zener diodes. Assembly failures and testing failures and overvoltage/overcurrent failures can happen to any component.
Since the other identical parts in the same Mouser bag worked perfectly, we can eliminate "dead even before stuffed and soldered" as an explanation. Only one Tucson board was affected; the other diodes on the other board were fine, AND the not-yet-used parts in the bag were fine.
That leaves "destroyed during board assembly" as a possibility. Too hot for too long during soldering. ESD damage (to two different parts!!??) during assembly. Too much tension / compression / torque during lead bending. Those kinds of assembly failures.
It also leaves "destroyed during amplifier power-up" as a possibility. Perhaps your PSU was not quite correct the first time(s) you powered up your Tucsons, and managed to fry some of the components on a daughter board.
It also leaves "destroyed during amplifier testing and listening" as a possibility. Perhaps you accidentally touched two of the mounting bolts at the same time, with something conductive: screwdriver, wrench, watch band, wire, chassis lid, etc. Perhaps this conductor managed to create a temporary short circuit which fried some of the components on the daughter board.
Observe that nothing written above, is specific to Zener diodes. Assembly failures and testing failures and overvoltage/overcurrent failures can happen to any component.
Thanks, Mark.
From all these details I will mostly take as a lesson the possibililies of "too hot for too long during soldering" and "too much tension / compression / torque during lead bending" as, though being cautious in general, I was not paying special attention to these fragile parts, I have to say. So I will be more careful in the future.
Other possibilities, I think, look less likely in my case.
Thanks a lot!
From all these details I will mostly take as a lesson the possibililies of "too hot for too long during soldering" and "too much tension / compression / torque during lead bending" as, though being cautious in general, I was not paying special attention to these fragile parts, I have to say. So I will be more careful in the future.
Other possibilities, I think, look less likely in my case.
Thanks a lot!
Did my first M2x swap today. I went from the OPA134 on the IPS7 board to the Cedarburg. It took about ten minutes. Nice work on both boards there Mark. I believe I like the Cedarburg more right now but I'm still in the honeymoon stage till I listen to more tracks.
Maybe a 1612A test soon.
Regards,
Dan
Maybe a 1612A test soon.
Regards,
Dan
Did my first M2x swap today. I went from the OPA134 on the IPS7 board to the Cedarburg. It took about ten minutes. Nice work on both boards there Mark. I believe I like the Cedarburg more right now but I'm still in the honeymoon stage till I listen to more tracks.
Maybe a 1612A test soon.
Regards,
Dan
It didn’t take much of a honeymoon. Mark’s Cedarburg has trounced the IPS7 I have. Clearly superior in all areas in my system.
If you’re searching for the best I strongly recommend you give the Cedarburg a try.
Regards,
Dan
It is precisely for these scenarios that I dislike the forum approach. One has to read over 5000 posts to learn about different front ends that are nowhere to be found in the opening thread.
Could mods append the info regarding IPS6, IPS7 and Cedarburg (and whatever other cards have come along the way) to the Opening Post?
It would be so useful for newcomers.
Thanks!
Could mods append the info regarding IPS6, IPS7 and Cedarburg (and whatever other cards have come along the way) to the Opening Post?
It would be so useful for newcomers.
Thanks!
They're on the opening page, i.e., among the first ten posts. Moderator 6L6 put them there. See whether you can find them either visually, just by looking, or else by using CTRL-F (on my browser anyway).
Also you can visit this delightfully helpful link: click me
If you are unhappy with the way Moderator 6L6 is doing his job, volunteer to become a moderator yourself and do it better. Then you can experience ingratitude, personally.
Also you can visit this delightfully helpful link: click me
If you are unhappy with the way Moderator 6L6 is doing his job, volunteer to become a moderator yourself and do it better. Then you can experience ingratitude, personally.
It didn’t take much of a honeymoon. Mark’s Cedarburg has trounced the IPS7 I have. Clearly superior in all areas in my system.
If you’re searching for the best I strongly recommend you give the Cedarburg a try.
Regards,
Dan
Lol! I too swapped out the Cedarburg for the others, even some other AD opamps in the IPS7, but not for long.
Cedarburg back in, and I even screwed the tops on.