Gus' MXL 603s mod - Pictures/Part numbers -thanks Flatpicker

Not to start yet ANOTHER thread about this, but for people interested in Gus' MXL 603/990/991 mod here is all you need to know, with pics. I am just trying to make it easier and more clear.

Special thanks to Gus for coming up with this one (sorry Gus) and Flatpicker too for answering my dozens of simple questions.

I did the 990s last week and enjoyed the improvement, but the improvement to the 603s is more profound. These are the best deal around in a matched pair, and if you don't already have some you need to pick up a pair. $200 u.s. for a matched pair with shock mounts and case!

Change ceramic caps C3 and C4 from .22uf ceramic to .22uf Metal Film Panasonic caps from Digikey

Change the capsule/Gate cap C13 (on back of PC board) from a .001uf (1000pf) ceramic to a 1000pf Xicon Styroflex polystyrene cap from Mouser

After those 3 simple cap changes the already decent mic becomes wonderful. I will be using thes mics more and more.

I did not find the PC board to be fragile at all (at least compared to the MC012) I recommend a decent iron with a clean tinned tip, and desoldering braid for removing the old parts. Apply the braid, then the iron to the braid, and when the braid soaks up the solder (turns silver) the lead is clean. It helps to use the very tip of the desoldering braid for more effective heat transfer, and for an easier time clip the used tip of the braid after cleaning each trace. Then just use the hot iron to poke the leads through, leaving holes for the new components.

This mod is very easy and should take about 10-15 minutes.

Here are some pics of the mic innards before and after. If you like the mod report back here with your findings. For the price everyone should have a pair of these.

http://www.pbase.com/sbushman/image/39069407.jpg

http://www.pbase.com/sbushman/image/39069409.jpg

http://www.pbase.com/sbushman/image/39069413.jpg

http://www.pbase.com/sbushman/image/39069410.jpg

Enjoy!
Shane

Wow - that has to be the clearest guide and easiest mod I've seen. :green: :guinness: :guinness:

Thanks for posting the pics, Shane. :thumb:

I would've taken pics of my mod, but my digital camera's broken. :sad:

Are these caps in the same position in the MXL 600's?

Now why does this thread upset me??????????

Oh, btw Shane, Gus was the one that originally came up with this mod (to me it's a given but maybe others don't realize this), so thumbs up for him! :thumb:

[quote author="Gus"]Now why does this thread upset me??????????[/quote]

Why does it? :?

Peace,
Al.

[quote author="Gus"]Now why does this thread upset me??????????[/quote]

Sorry Gus. Didn't mean to leave you out. Much thanks to you. I will edit the thread to give you credit for this great little mod. I am mucho happy with the improvement in my mics!

Sorry about that. Flatpicker was answering all my questions so I started assuming he pioneered this mod on his own.

Shane

My fault - I should have mentioned in the other thread that it was from Gus, but all is well. :grin:

We all made our contributions and now we have real photos for the META, which is pretty cool. :thumb:

I have a pair of these mics, and would really like to try this mod. But...
Im having trouble finding these capacitors in sweden, and since the shipping cost to sweden is about ten times the cost of the components, I was wondering if there are other suitable replacement parts that i might better be able to find more nearby?

Or atleast in one place, so that i dont have to pay for shipping two packages.

Thanks!
/Jonas

Jonkan
If you can?t find 1000pF polystyrenes, polypropylenes should sound good ? in fact, I?m going to try them here myself. The 1000pF polypros may be too large physically, tho. To keep physical size to a minimum, look for the lowest voltage rating ? hopefully you can find 50V ones. Also, smaller values such as 820pF or even 680pF should work just fine if you can?t find or fit the 1000pFs.

As for the 0.22uFs, any small good quality stacked metal film will do. Again, just look for a low voltage rating (50V) and size should be fine.

I had no problems fitting a no name 1000pf/630V polyprop into my SC150 mic, which is about the same size as the MXL 603. The cap is about 5 x 11 mm. Some others like WIMA FKP with high voltage rateting may not fit, though.

gus. thank you
:guinness: :guinness: :guinness: :thumb:
Catagory 5 thanks for the posting.

this is perfect for doing my first real mod. pretty step by step instructions. way cool. you guys rock.

[quote author="Flatpicker"]Jonkan
If you can?t find 1000pF polystyrenes, polypropylenes should sound good ? in fact, I?m going to try them here myself. The 1000pF polypros may be too large physically, tho. To keep physical size to a minimum, look for the lowest voltage rating ? hopefully you can find 50V ones. Also, smaller values such as 820pF or even 680pF should work just fine if you can?t find or fit the 1000pFs.

As for the 0.22uFs, any small good quality stacked metal film will do. Again, just look for a low voltage rating (50V) and size should be fine.[/quote]

The Wima 1000pf will fit, but you may have to extend the leads with a wire or jumper. The leads are small and meant for pcb mount.

Shane

ok, i think i can find some good polypropylene caps, though they are 100v ones. Would they be too big probably?

And another newbie question.

Stacked metal film, is that metalized mylar film caps? Or metalized polyester capacitors? Im confused..

As you can see, im still a bit confused as of which capacitors to buy. :?
So any further help would be greatly appreciated.

thanks!
/Jonas

[quote author="Jonkan"]...Stacked metal film, is that metalized mylar film caps? Or metalized polyester capacitors? Im confused...[/quote]either one's fine - probably the same thing

Thanks!

I just opened up my mics, and to my surprise they dont look exactly the same as the one in the picures in this thread. There are wires running from the .22uF capacitors connecting them somewhere (havent looked too hard exactly where yet).

I have an early run of the mic i think, could the wires be some kind of fix to the pcb that newer revisons dont have?

Would it probably be safe to mod it anyway, though it will be a little harder to solder in place.. (since i have to solder the wires also)?

/Jonas

[quote author="Jonkan"]I have an early run of the mic i think, could the wires be some kind of fix to the pcb that newer revisons dont have?[/quote]Yes, the early ones were made this way. Those wires are going to the 0.22uFs that you need to replace. Just be sure and solder the wires back to the same place on the caps when you are finished.

I dont mean to make a big giant wave here but I am tempted to open my mouth.

Gus went into great detail with this mod several weeks ago with me on the telephone and specifically asked me to not post it up here. I am quite certain that if Gus wanted this info posted in this form he would have stepped right up and put a nice little package together for everyone here, its not like he's some arbitrary member of this board, he posts every day. Could anyone here have figured this out? Sure. Gus put the hours in however and we should try to respect that. This is certainly a horrible motivator to get someone who is REALLY good at this stuff to continue to contribute. Giving someone credit doesnt amount to a whole lot if their original intention did not involve publishing it on the internet in the first place.

Ive been told a lot of really cool things by a lot of really cool guys who were really super with sharing their knowledge but also really careful about not exploiting it. Lots of the stuff I learned I may have eventually figured out for myself but the simple fact is they figured it out first, told me about it and Im not gonna go and blab about so and so's cool secret they shared with me. Im not suggesting we get all smoke and mirrors and chicken foot voodoo about this stuff, but there is a fine line that I think is worthy of respecting.

There is little doubt that this info was shared here with the best of intentions as everyone that posts here is virtually fantastic. There are also lots of lurkers here who arent fantastic at all and not everyone wants their hours and hours and hours and hours of experimentaiton exploited by these parasites.

I think a simple rule we should all consider, when it comes to the members here and their achievements, if you didnt think of it, maybe just tell them how much you like their idea and suggest they put it up here before you go and put their idea up here for them. And yes, I know how much of a double standard this can appear to be coming from a group of people who are so focused on cloning old ideas from the 70's and 60's, but we can all learn from each other, we should all respect each other and keep the direction of the group in the right direction. Think a little before posting stuff like this, thats all. We are not ALL a bunch of thieves here as manufacturers would liek to brand us and not everything a group memeber here does necessarily means publication on this site.

dave

You make a good point Dave, and since I started this "third" thread regarding this particular mod I feel I should respond here. The reason I did it is because after I finally got he parts and did this mod I realized it was about 10 times simpler than the other threads made me imagine. I am by no means one of the experts here, but I am also not a novice and I just thought I could make things a little clearer for those who want to get involved in this type of hobby.

I do apologize to you, Gus if it upsets you that this was made public, but for such a simple and effective mod I thought it would be encouraging to those who have yet to wield a soldering iron in confidence to start thinking positively about their potential with regards to DIY.

I will not be upset if the moderators decide to do away with this thread completely if it genuinely causes upset, or makes me look as though I am disrespecting one of the major contributors to this group.

I did, however, think that the major purpose of this group was to make this type of information available to those who are curious about DIY. I have learned a great deal from this forum, and hopefully as time goes on I will be a better contributor too. Again, this information was passed on by me but was all collected here on this forum to begin with. I merely attempted to make things more clear, since (if you take notice) the other threads seems to digress quite a bit. What I've done is not entirely different from the many Meta threads (which I do find helpful) floating around here. I tend to not think of lurkers as busy thieves, but potential members of the community here, and maybe even future contributors. If this thread is honestly upsetting to Gus, or anyone else (for any reason) then please moderators, delete it (or tell me how to make it unoffensive and I will edit the original post). I do not want to be known here for upsetting anyone. I enjoy this forum far too much.

That said, if it is understood that my intention was not to reap glory, nor to make Gus' hard work widespread for the unappreciative, then please regard this thread for what it is...a summary of useful information from the other "less concise" threads. I apologize to Gus for not crediting him in the original post, but this is a great example of how long threads like this one's predecessors lose things like this after page 6 or 7.

Sorry to all who were upset by this. My intentions were innocent.

Shane