There are tons of forums out there discussing BLA's mod to the Apollo on various sites, but none of them actually discuss the details of DIY modding for those that can solder and have some what of a knowledge to DIY modifications.
I don't claim to be an engineer, but am handy with a soldering iron, and can follow a basic schematic to a point, as well as have some specilized equipment, that I know somewhat how to use (maybe 10%).
I started off with may different audio cards/external gear, but as my home studio has gotten more elaborate, I've developed the itch to mod things.
There are tons of people who reviewed the original Silver Apollo and BLA's mod, but not much info on the newer black version.
Well I have a black 8 (not 8p) version, and i'm in the process of modding it. And while not trying to copy BLA's work, I find it a good basis to start off with. Considering the amount of work it takes, time, and cost of parts, their price is actually fairly reasonable.
There was a ton of pics/info on the gearautopsy website which seems to be down, but I managed to acquire photos (took a while, and some intense internet searching), and with the use of the ICs datasheets, have somewhat of an idea of changes they made. With all that said, I'm still a little stumped in a few areas.
If you look at the generic low res photo on their mod page, you will see an image of a generic modded black Apollo (img 1).
Image 2 is my stock unit (before modding).
If you carefully look, it isn't much different than the silver face, except they went with SMD caps, and changed to the lme49720, but kept the 5532s and 5388eq, and changed the output d/a converter.
-OPAMP modding
Well, the 2134 seems to a favorite by many, but I had a hard time deciding on which chip to use. So after discussing it a little with gearautopsy (online), it was suggested to use a socket mod, so I could switch anytime.
Seeing as I have no idea how the LME 49720 plays a role in everything, I decided to keep them, but use the metal can versions. On other forums they said it sounded better. Not sure how that will pan out, or if that equates in all the areas of the board, but i'm sure it does in some places (maybe it has no effect on the Apollo's layout/design, I have no idea). Just not sure which ones are part of the audio path vs the voltage rail, vs A/D and D/A section. Needless to say, I'll just change them all unless someone points me in the right direction, or tells me otherwise.
There were tons of pics of the BLA modded silver face, but couldn't find any of the black face, and no pictures of the bottom of any of the units. The board seems to be a 3-4 layer board, so I've been having a hard time making traces, and i'm not at the point where I want to spend the hours to use my meter to track every trace (wish there was a schematic available). Here is 2 pics of the bottom of my board (img 4 and 5). Any idea where these trace to, their function, or any more info on the bottom of the board/caps/etc that can be modded? Maybe its as simple as mic vs line select, and the relay switches between the two? Maybe a function of the optical ins/outs or spdif.
Where is the clock circuit? Mine is so unstable, that I must have a bad cap in there somewhere (was this way since I bought the unit, which was a b-stock unit).
I've started switching all the LME 49720's to metal can versions.
I've also started placing sockets on most of the 5532s, except right after the preamp section. Just not sure if that is also true on the line inputs vs mic/xlr sections, as there are no mic preamps (PGA2500) in all of the sections. Without the mic preamps, does what gearautopsy hold true on the line inputs as well (dc servos to compensate for any offset at the output of the pres). I also don't know where/what the middle ics (placed vertically in a different pattern then the "line of ics") do, or trace to (img 99 shows an overview, the middle section).
-decoupling
I'm also puzzled by the BLA pic (img 1) where it appears they have a super big cap on the A/D 5388eq on the RIN2, and some where along the lower pins, possibly the DVDD2 (on the right side of the 5388). There isn't any upgrade on RIN1, or DVD1. (5388 img 3 - schematic). Obviously the vref appears to be upgraded (I decided on the BC 136 220uf caps, but likely will change to Panasonic low ESR caps), but why the uneven match from left/right along the 5388 in/on/around the the audio path. Maybe i'm being stupid and they added caps to the VSS section on the right, but not the left/top/bottom? And if that is the case, why did they mod only one side, and why only that side? Their image actually show the very first 5388 with a meg cap on the left, and the other 3 on the right. The smaller ones are on the right as well at the bottom section and must go to the DVDD2, unless it decouples from the digital microcontroller as indicated by the schematic (bottom right 3 pins, 23-25 somewhere). And yes the orientation is correct and lines up w/ the schematic.
So, in essence, i'm not sure what caps to upgrade on the 5388eq. I'm not debating on brand/type/size/voltage caps, just which sections they upgraded, and possibly if upgrading more areas, if physically possible, will yield any better results, or worsen things with more oscillations and noise.
Also, if modding the bottom of the board will yield any results, or is needed, and where/what these go to.
The rest of the pics are my modding in progress.
Any help, feedback, even if negative, is welcome. Thanks for taking the time to read my post and/or reply.
-Cliff
I don't claim to be an engineer, but am handy with a soldering iron, and can follow a basic schematic to a point, as well as have some specilized equipment, that I know somewhat how to use (maybe 10%).
I started off with may different audio cards/external gear, but as my home studio has gotten more elaborate, I've developed the itch to mod things.
There are tons of people who reviewed the original Silver Apollo and BLA's mod, but not much info on the newer black version.
Well I have a black 8 (not 8p) version, and i'm in the process of modding it. And while not trying to copy BLA's work, I find it a good basis to start off with. Considering the amount of work it takes, time, and cost of parts, their price is actually fairly reasonable.
There was a ton of pics/info on the gearautopsy website which seems to be down, but I managed to acquire photos (took a while, and some intense internet searching), and with the use of the ICs datasheets, have somewhat of an idea of changes they made. With all that said, I'm still a little stumped in a few areas.
If you look at the generic low res photo on their mod page, you will see an image of a generic modded black Apollo (img 1).
Image 2 is my stock unit (before modding).
If you carefully look, it isn't much different than the silver face, except they went with SMD caps, and changed to the lme49720, but kept the 5532s and 5388eq, and changed the output d/a converter.
-OPAMP modding
Well, the 2134 seems to a favorite by many, but I had a hard time deciding on which chip to use. So after discussing it a little with gearautopsy (online), it was suggested to use a socket mod, so I could switch anytime.
Seeing as I have no idea how the LME 49720 plays a role in everything, I decided to keep them, but use the metal can versions. On other forums they said it sounded better. Not sure how that will pan out, or if that equates in all the areas of the board, but i'm sure it does in some places (maybe it has no effect on the Apollo's layout/design, I have no idea). Just not sure which ones are part of the audio path vs the voltage rail, vs A/D and D/A section. Needless to say, I'll just change them all unless someone points me in the right direction, or tells me otherwise.
There were tons of pics of the BLA modded silver face, but couldn't find any of the black face, and no pictures of the bottom of any of the units. The board seems to be a 3-4 layer board, so I've been having a hard time making traces, and i'm not at the point where I want to spend the hours to use my meter to track every trace (wish there was a schematic available). Here is 2 pics of the bottom of my board (img 4 and 5). Any idea where these trace to, their function, or any more info on the bottom of the board/caps/etc that can be modded? Maybe its as simple as mic vs line select, and the relay switches between the two? Maybe a function of the optical ins/outs or spdif.
Where is the clock circuit? Mine is so unstable, that I must have a bad cap in there somewhere (was this way since I bought the unit, which was a b-stock unit).
I've started switching all the LME 49720's to metal can versions.
I've also started placing sockets on most of the 5532s, except right after the preamp section. Just not sure if that is also true on the line inputs vs mic/xlr sections, as there are no mic preamps (PGA2500) in all of the sections. Without the mic preamps, does what gearautopsy hold true on the line inputs as well (dc servos to compensate for any offset at the output of the pres). I also don't know where/what the middle ics (placed vertically in a different pattern then the "line of ics") do, or trace to (img 99 shows an overview, the middle section).
-decoupling
I'm also puzzled by the BLA pic (img 1) where it appears they have a super big cap on the A/D 5388eq on the RIN2, and some where along the lower pins, possibly the DVDD2 (on the right side of the 5388). There isn't any upgrade on RIN1, or DVD1. (5388 img 3 - schematic). Obviously the vref appears to be upgraded (I decided on the BC 136 220uf caps, but likely will change to Panasonic low ESR caps), but why the uneven match from left/right along the 5388 in/on/around the the audio path. Maybe i'm being stupid and they added caps to the VSS section on the right, but not the left/top/bottom? And if that is the case, why did they mod only one side, and why only that side? Their image actually show the very first 5388 with a meg cap on the left, and the other 3 on the right. The smaller ones are on the right as well at the bottom section and must go to the DVDD2, unless it decouples from the digital microcontroller as indicated by the schematic (bottom right 3 pins, 23-25 somewhere). And yes the orientation is correct and lines up w/ the schematic.
So, in essence, i'm not sure what caps to upgrade on the 5388eq. I'm not debating on brand/type/size/voltage caps, just which sections they upgraded, and possibly if upgrading more areas, if physically possible, will yield any better results, or worsen things with more oscillations and noise.
Also, if modding the bottom of the board will yield any results, or is needed, and where/what these go to.
The rest of the pics are my modding in progress.
Any help, feedback, even if negative, is welcome. Thanks for taking the time to read my post and/or reply.
-Cliff
