[uzziah]

edwood or anyone: could somebody answer my last post? my thinking is i need

A. 1 brown dog adapter for dip8 compatability (is it "SOB to dip8" one?) link?
B. 1 dip8 socket to be soldered to above brown dog
then i can opamp roll dual channel opamps
am i on the right track?

if i want two single-channel opamps:
C. get another browndog; dip8 to dual version
D. solder two opa627au (as an example) to said smd browndog
E insert said browndog with 627's into dip8 which resides on the first browndog which all of resides on the EMU

hehe. this is funny to write. am i on the money?????????????????

2nd question:
can i utilize 2 637 opamps in this configuration? is the gain enough? will it be stable?

 

[llmobll]

Quote:

Originally Posted by uzziah edwood or anyone: could somebody answer my last post? my thinking is i need A. 1 brown dog adapter for dip8 compatability (is it "SOB to dip8" one?) link? B. 1 dip8 socket to be soldered to above brown dog then i can opamp roll dual channel opamps am i on the right track? if i want two single-channel opamps: C. get another browndog; dip8 to dual version D. solder two opa627au (as an example) to said smd browndog E insert said browndog with 627's into dip8 which resides on the first browndog which all of resides on the EMU hehe. this is funny to write. am i on the money????????????????? 2nd question: can i utilize 2 637 opamps in this configuration? is the gain enough? will it be stable?

Wow, alot of progress & questions from you....

I want give some advice, DROP the whole OPA637 stuff, it isn't worth it. You're talking alot of $$ in amps without alot of performance. I know you have a grado can, but more performance can be found elsewhere....

If you want to roll amp go with either AD8620 or AD8066, personally they sound very very similar but i like the AD8620 alot. Very very detailed. The AD8066 tends to be very unstable, but good....

1. Buy pass the output caps.(i think you have this done)
2. Take the output buffers OFF.(With an amp you don't really need them)
3. Change the opamp. (8620 will sound great.)
after this you have reached the limits of the card, better interconnects and even (dare i say) better amp would yield much more improvements.

4. Lastly i say... play with the DSP effects in Patchmix. People underestimate the change in sound with just a few simple effects. I used to love resampling, now i just can't live without my DSP effects. They make my Soundcard sing.

 

[uzziah]

Quote:

Originally Posted by llmobll Wow, alot of progress & questions from you.... I want give some advice, DROP the whole OPA637 stuff, it isn't worth it. You're talking alot of $$ in amps without alot of performance. I know you have a grado can, but more performance can be found elsewhere.... If you want to roll amp go with either AD8620 or AD8066, personally they sound very very similar but i like the AD8620 alot. Very very detailed. The AD8066 tends to be very unstable, but good.... 1. Buy pass the output caps.(i think you have this done) 2. Take the output buffers OFF.(With an amp you don't really need them) 3. Change the opamp. (8620 will sound great.) after this you have reached the limits of the card, better interconnects and even (dare i say) better amp would yield much more improvements. 4. Lastly i say... play with the DSP effects in Patchmix. People underestimate the change in sound with just a few simple effects. I used to love resampling, now i just can't live without my DSP effects. They make my Soundcard sing.

that is EXACTLY what i'm going to do

i have a spare 8620 (want to guess where it came from?

) i think i might change the output caps while i'm at it: but i'm not going to buy the most expensive ones. maybe just some panasonics. or maybe i won't do that at all. you're right about the 637. i just want to try it (i.e. switch it from my/your pimeta to the card, and put the 8620 in the card, just for the hell of it)

question: what about patchmix settings?

 

[Glassman]

637 is no-go on soundcards.. you have to use 627 instead..

 

[uzziah]

so: when i remove the buffering opamps, do i need to bridge some of those pads or something?

 

[uzziah]

having trouble getting the buffering opamps off. my iron is set to 345C. i'm running braid over the pads, and then pressing down in the spots where the solder joints are. i've got some solder off. i'm trying to loose one side at a time. i.e. heat up the joints and undo one side by pulling with needlenose pliers. is there a better way? i know to take it easy on the board or i could pull up traces, so i'm being careful and not applying much pressure. i'm going to keep attempting with the braid

success! one side of one buffer free and clean! no pulled traces all is well. moving on

 

[uzziah]

all done. i bridged pins 1-2 and 5-6 on each opamp-buffer pad. do i need to bridge 1-2-3 and 5-6-7? s delieus mentioned that pads 2-3 and 6-7 were already bridged, so it wasn't necessary

well, i have mixed results:
1. the sound is much more transparent and "live". seems like a good mod, but i have some problems

problems
1. with the power on my pimeta, my headphones on AND the amp connected to the soundcard, i get a sort of "hiss" if i turn the volume knob. if i turn it up very high it stats to crackle and pop. i don't hear any of this if i don't turn the knob. i don't get this if the amp is not connected to the card
2. it's as if the gain has been turned way down: i have to use much more of my volume knob to get reasonable volume. also, if i turn it up very high it starts to click, pop and then the sound dies

obviously something is wrong. i'm wondering if perhaps my solder bridges aren't making good contact or something. i hope i haven't damaged anything with over-heating. this is all very strange. i don't have a digital camera, so i can't take any pics unfortunately.

 

[uzziah]

oh baby! oh baby!

problem solved. wahooo!

i took the card back out and connected pins 1-2-3 and 5-6-7 of each opamp buffer pads. i also removed some solder from pin 4 on one of the buffers. i'm not sure, but it's possible that i had a solder bridge between pins 3-4 on the bottom opamp-buffer (with the pci slot facing down). anyway, i'm happy now

i was so scared i screwed up my card. i nearly cried when i turned the power on my amp on and turned the volume up - no hiss!! no snap crackle or ****ing pop!
yeah.

anway: folks; what do you think my problem was. i'm leaning towards an imperfect solder joint between pads i needed bridged. what you think?

anway, things sound very very good now. all that's left for me now is to put an ad8620 in there

, and most likely change some caps as well - suggestions on capacitence and brand/type i should consider? i don't want to spend mucho $$$

is this the correct brown dog to get my ad8620 on there?
http://cimarrontechnology.com/index....PROD&ProdID=20

and which brown dog is it so i can solder a dip8 socket on there? i may want to do that instead so i can roll opamps. heck, i suppose i could just unsolder this ad8620 from the dip8 socket it's soldered to, and solder the ad8620 directly to the board

lots of words (yes, glassman, i really just need someone to talk to)

happy am i. moving on

 

[Magsy]

Quote:

Originally Posted by uzziah oh baby! oh baby! problem solved. wahooo! i took the card back out and connected pins 1-2-3 and 5-6-7 of each opamp buffer pads. i also removed some solder from pin 4 on one of the buffers. i'm not sure, but it's possible that i had a solder bridge between pins 3-4 on the bottom opamp-buffer (with the pci slot facing down). anyway, i'm happy now i was so scared i screwed up my card. i nearly cried when i turned the power on my amp on and turned the volume up - no hiss!! no snap crackle or ****ing pop! yeah. anway: folks; what do you think my problem was. i'm leaning towards an imperfect solder joint between pads i needed bridged. what you think? anway, things sound very very good now. all that's left for me now is to put an ad8620 in there , and most likely change some caps as well - suggestions on capacitence and brand/type i should consider? i don't want to spend mucho $$$ is this the correct brown dog to get my ad8620 on there? http://cimarrontechnology.com/index....PROD&ProdID=20 and which brown dog is it so i can solder a dip8 socket on there? i may want to do that instead so i can roll opamps. heck, i suppose i could just unsolder this ad8620 from the dip8 socket it's soldered to, and solder the ad8620 directly to the board lots of words (yes, glassman, i really just need someone to talk to) happy am i. moving on

The AD8620 just goes on without an adaptor but as you have seen removing the buffer opamps, its a pita and requires so much care every time.

That browndog is the right one to put a dip socket on for rolling. Soldering that browndog to the emu is quite easy...

 

[bg4533]

Quote:

Originally Posted by uzziah all done. i bridged pins 1-2 and 5-6 on each opamp-buffer pad. do i need to bridge 1-2-3 and 5-6-7? s delieus mentioned that pads 2-3 and 6-7 were already bridged, so it wasn't necessary

I am not really sure about this. In my thread I suggested just bridging 1,2,3 and 5,6,7 either way. Even if they are connected it isn't really going to hurt anything.

 

[uzziah]

Quote:

Originally Posted by bg4533 I am not really sure about this. In my thread I suggested just bridging 1,2,3 and 5,6,7 either way. Even if they are connected it isn't really going to hurt anything.

yeah, i'm just wondering. the less solder the better as far as i'm concerned. i just really don't even know which is #1? i pretty much just followed magsy's picture.


I I I I
I I I I

I I I I
I I I I

ok so there you have the pads for the two buffering opamps (please assume that the PCI slot is facing down)

i'm calling the pins like this:

8 7 6 5
1 2 3 4

is that correct? there seems to be something resembling a dimple to the left of the pads

 

[uzziah]

so right now i have

1-2-3 bridged and 5-6-7 bridged per that diagram for each opamp-buffer pads

 

[uzziah]

ok, now i've replaced the stock opamp with ad8620. i just soldered it directly to the board with kester 2% silver-bearing solder (thanks, Qnexus!)

well; all i can say is: i'm in business, now. every step of the way made significant improvements

1. bridge output caps: removes a "vail". more clarity
2. remove output buffers: same thing, and seems "faster." more "live"
3. replace opamp with ad8620: very nice. i had an ad8620 in my pimeta, and it was nice, but a bit bright with my grados. with the 8620 on the emu it is a bit brighter, but i have 637's in my pimeta, and that helps smooth things out.

overall, it's been improved significantly. i can even hear allison krauss opening her mouth at the mic (i thought something was wrong at first

). i'm really happy i did these options. didn't cost my anything thanks to Qnexus (well, maybe a breakout cable Q?)

well, next upgrade is to replace the electrolytic capacitors. i'm leaning towards panasonic caps, with a bit more capacitence than stock caps. i'd really appreciate suggestions here. i can also go up a bit in price, but i'm uncertain it's worth it

 

[MisterDeadeye]

Did you really just bump almost ten topics on the same thing? I'm sure someone would have posted in the first or second helping you...

 

[hallom]

just wanted to be sure, thanks anyway!