Man, this mic is busting my BALLS! I've done all the mods mentioned ... Peluso capsule, 2480 xfmr, black gate & ansar caps, yadda yadda. I've also had to go in and rewire the whole thing, because I've not been able to get it up and running properly yet. Finally had some signal passing - but still very low and noisy - the other day. Left the mic warming for a few hours while I set up a mic array as a vocal test for my wife ... then when I got back to the 460 - nuthin but hum - FRAK!! Stand back, I'm a-goin' back in ...



mud

Apex_460_Mod,_small.JPG (38 Kb, 60 downloads) Apex 460 on the Mod Bench

When I was learning to do these mods it was always all or nothing for me when it came to getting sound.
It seemed to be very easy to knock of the wires going to the tube socket and any other wire in that area. Double check that first.
If there's a lot of solder flux on the board that can cause the mic to be really noisy.
Besides that, check the polarity of the black gates and make sure there are no solder bridges or wires cuasing a short.

Craig

Hey guys,

I think I know what is wrong. I have done a lot of these and there seems to be a week point in the circuit board, right at C8.What you need to do is bridge both sides of the cap, and connect the lead going to the transformer directly to the cap. I will bet this is the problem.

Jeff

Mudbean,

I'm done with my mod but I couldn't find any ansar caps. I went with a Wima instead. Where did you locate yours?

I had the same problems that Jeff mentioned. The metal within the circuit board that connects the internal routing can separate or break away from the board leaving no connection. This happened to me at the output of C8 to the tube socket, so I just ran the wire directly to C8, otherwise I had no sound. It took me changing caps in the same spot a few times for this to happen, so it might not happen if you make fewer changes in the same spot.

The Ansar capacitors are pretty much a euro brand of metalized polypropylene capacitor, actually double metalized, but I'm not sure that makes a huge difference as single metalized. I haven't found any place in the US that sells them and the Canadian site that did no longer stocks them.

Personally, I tried a metalized polypropylene 2.2uf/250 cap in C8 and didn't like it in either of my mikes, too bright and sterile for me. I preferred a metalized polyester caps. They sounded warmer to me, but it really depends on what you want. I have the CEK-12 and Cinemag 2480 in there without the cathode follower. Tried it with and without the Black Gate in C6. I like it with C6 personally.

I tried a bunch of different caps for C8 in my 1050 and settled on a Black Gate 3.3uf/250 for C8 (it's the lowest value available from Black Gate. I might try it in my 460 just to see). It had the warmest sound for what I'm looking for, but I still have the stock capsule in there right now and have only changed the tube to a 12AT7, which sounds excellent. I will be using the CEK-367 eventually.


For anyone who hasn't done these mods yet and is wondering how each mod changes the sound, here are my observations in simple terms, starting with a stock 460, in the order of my mods. Some are different than what I've read in different threads;

-Replaced the 12AX7 with a 12AY7. Drops the level of the mic and cleans up the sound alot.

-Disconnected C9 and C10. Also added Cinemag 2480 (because I removed the wires to C9 and C10 which detaches the tranny from the 7 pin connector and, trust me, you want to disassemble the tranny screws as few times as possible 'cus the tiny phillip's heads strip easily. Probably should've just removed the caps for the first test). This opened up the mic and added a fullness and dimension that is amazing. I'd say that the Cinemag made a very big difference, even with the stock capsule, which sounded pretty good at this point.

-Removed C6. This dropped the level again, but it seemed to thin it out a bit. It removed some of the dimension I talked about.

-Removed C7. Not much difference. Maybe a bit clearer and thinner as described above. Very slight. Not worth removing IMHO.

-Replace C8 with metalized polyester 1uf/250v. Cleaner in that it removed the texture that the electrolytic has.

-Removed cathode follower. This opened the sound up and made things clearer. Not as much bottom fullness.

-Replaced stock capsule with Peluso CEK-12. This scared me at first. The level dropped yet again and it didn't sound a whole lot different at first.... but then I realized that the mic sounded the same at 3" as it did from 10"!!!! Then I brought the level up on the mixer and could hear how smooth this capsule sounds. Really nice!!!

-Replaced C8 with the same type 1.5uf/250v cap. This brought back some bottom that I was missing from earlier mods.

-Added Black Gate 100uf/50v (25v not available) at C6 and put C7 back in (necessary for C6). This gave me back some level (which is why it's there) and the dimension that I heard when I first put the Cinemag in returned. It also filled out the overall sound, made it a bit thicker. This would obviously be a matter of taste. Do what you like best. I prefer C6 and C7 in there because you'll really need to crank the preamp to get the level up otherwise.

-Replaced C8 with a metalized polypropylene 2.2uf/250v. The larger value did thicken the bottom, made it a bit muffled, but I didn't like the ultra clear, brighter, more sterile sound of the higher range. Kinda brought back the high mid boost of the stock capsule only more intense. Some may like this, I didn't. Plus the cap barely fit in there. It really had to be forced. Wasn't worth it for me.

- Final mod, replaced C8 with sub-miniature metalized polyester 1.5uf/400v. This gave me the best balance of clarity, fullness and warmth, which is what "I" wanted from this mic.

These are preliminary results and I'm looking forward to more "field" testing, if you know what I mean.

Hope this helps,

Lucio

Craig, Jeff - Thanks for the tips! I plan on wiring direct between the tube socket & caps when I go back in ... gonna bypass the PCB as much as possible.

qbert - Sorry, don't recall where I got 'em ... just did a Google search and went with whoever had them for sale ... bought them about a year ago, though.

Lucio - Very cool! I haven't seen where anyone has posted all this info in one place, thanks!

I'll post my results (when I get around to the work ... eeeeeventually, right, Mad?)

mud

Lucio,

Based on your recommendations, I'm probably going to put C6 and C7 back in (black gates). Did these add to the bottom more than changing C8?

Craig

Has anyone pulled out the PCB and just gone point to point? Or maybe a small breaboard?

jmp

quote:

Originally posted by John Mark Painter:
Has anyone pulled out the PCB and just gone point to point? Or maybe a small breaboard?

jmp

That wouldn't be a bad idea, either (breadboard) - there aren't all that many components in there. I like the idea of some kind of board in there, really only to help hold things in place.

mud

Craig,

I only used a Black Gate at C6. C7 is the original film cap.

I would say that C6 definitely added (or changed when removed) more than just changing to a larger cap at C8 did. It's more 3 dimensional, to me anyway. But, I wouldn't use a 1uf cap for C8. The 1.5 seems to add just enough. The combo of C6 with the Cinemag 2480 just took the mic to a different place.

Too large a cap at C8 can start to get muddy sounding, which is probably why others have bypassed the larger cap with a smaller one. Even the polypropylene that I used, while making the upper range too much for me, still got a bit muffled at the bottom.

For me, C6 is important to the character of the mic. It totally changes it. But of course, again, it all depends on what you want from the mic.

John,

I know that was mention before and wasn't recommended, but I don't know if anyone actually tried to do it. It would be interesting.

Also, to anyone thinking about doing these mods, be patient. Everything is pretty tight and tiny to work with. I had connections come loose just taking it apart. Actually, before I changed anything, I drew a picture of the circuit boards with all the connections and wire colors. That way if I got lost I knew where everything started. The schematic is great, but the way it all goes together is quite different than you would think. This coming from someone who hasn't done this before, but I'm a quick study and catch on fast (relatively speaking).

Lucio

To anyone who wants to get a Cinemag transformer for this project; Order them through Cinemag not Peluso.

I just ordered a 2480 for my 1050 from Cinemag and they said it would cost $42.00. The one I ordered from Peluso cost me $75.00!!!

Moral of the story; Buy the Cinemag's from Cinemag and save $33.00.

Lucio

I have more of the unmarked Apex 460 microphones in with 1 layer of mesh in front of the capsule for anyone who is interested. Check out the pictures on e-bay and if you want any, contact me directly.

jctaudiodesigns@cox.net

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=320103504604

Weird....I've actually gotten Cinemag transformers cheaper from Peluso. With me he said he bought them in large quantities so it was a few bucks cheaper from him (not a lot just $4 or $5 less than from cinemag)....odd...I wonder what happened with that? Bummer.

It looks like Musician's Friend is selling Nady 1050 for $199. That's cheaper than the last couple of (new) 1050's I got on Ebay.

Yeh, I noticed that too, what can you do? They also have the TCM1100 for $169. This mic is supposed to be similar to the coveted MXL V77.

I have an V77 and a friend, whose voice sounds best on the V77, wanted one but couldn't find one, so I told her about the TCM1100.

Anyway, she bought a 1100 and we put it up next to my V77...they really sound pretty much the same. I was really surprised. The body's a little shorter than the V77 and the insides are arranged differently, but just put in a better tube and you're done. More of a neutral sounding tube mic.

I just changed out the Zener Diodes on both mic's power supplies and it seems to soften the hard edges a bit.

Also put the Black Gate in at C6 on the 1050. Very nice. I tried it without first and the mic got brighter and thinner. Not bad, but not what I want for this mic. I like the Black Gate in C8 alot on this mic.

I have the Cinemag 2480 coming next week. Can't wait to hear it in the 1050. I have to save my pennies for the CEK-365 though. Must..have..patience...

Lucio

Hey Everybody!

I just want to start off by saying Hello, and thanks for all the insight and knowledge you all provide. It's people (like you all) helping people (newbies, like me) that keep DIY alive and well. Thanks!

Anyways...I am currently waiting for my unmarked 460 to arrive, and I was reading up on some earlier discussions relating to some power supply mods. My question relates to the discussion that honkyjonk and MPCNYC were having earlier.

MPCNYC: you said you weren't sure if simply using a rotary switch between diode sets would work properly. Well, I was wondering if one could configure a linear taper pot set up as a voltage divider to do the same task. Would that make the voltages being supplied to the capsule too unstable?

Thanks so much for your insight and anybody feel free to let me know. This whole DIY thing is a trial and error learning experience. Hope I get better at it!

...not knowing all the particulars of power supply design I still would be inclined to say that it's not quite that simple. To switch between diodes I would assume that you would actually have to have the diodes there to switch between. I'm not even if you'd have a switch there would work with the diodes...who knows it may cause a surge to the mic, loud pops when switching....I haven't tried so I honestly say I don't know.

My power supply and mic are finally completed (my friend finally got to it last week) My power supply will have a pot on it that will change the voltage of just the capsule (from about 55 to 75v) More regulation was built into the supply in order to seperate the voltage (160v) that goes to the tube from the voltage the goes to the capsule: the mic and the cable had to be mod'ed as well to get things working that way. I should go and pick it up monday, so I'll post when I get it.

I went back and put a Black Gate in C6 and a metal film in C7, and with the other mods I've done, I prefer it with the those caps. I thought I liked it without, but after listening to the recordings I made with it, the low end was too absent.
I like the Ansar 1uF at C8, though.

Craig

Craig,

I'm with you on this, much fuller sounding with C6 & C7. Makes the mic louder too, so you don't have to crank the pre as much.

You changed the zener diodes to the 56volt if I remember right. That actually makes a bigger difference than I first realized. I tried putting the originals back in after I tried the 56v and the difference was huge. Much more forward in the mids (makes the mic seem louder), sounds like a different mic.

Anyway, that might be why I didn't like the polypropylene cap in C8, 'cuz it opened the upper mids more. But the 56v zeners pull that back so a polypro probably balances that out some. I'm gonna try it again now that I have the 56v zeners in (which I prefer).

Did you mic seem to get quieter when you put the CEK-12 capsule in?

With mine the stock capsule got louder the closer you got to the mic, but with the Peluso the level stays the same from about 12" to 3". I just want to make sure everything's working properly.

Thanks,

Lucio

It's interesting. I've tried 56 all the way up 82 volt zeners. You can really "tune" the mic that way. I've mentioned it before, but I've ended up sticking with the zeners that were around 80v.