MPCNYC,
Thanks, I'll check it out.

Craig,

O.K. That makes more sense.

Did you notice a big difference changing C1 and C2 for the Black Gates? Just wondering if it's worth the $$$. In the homerecording thread, some guys say they leave C1 and C2 alone.

Thanks,

Lucio

Lucio, black gates are killer in terms of an electrolytic. An alternative, which may be better sounding and definitely cheaper are Panasonic Metalized Polypropelene caps, that's what I've been using and they sound really good to my ears. The are kind of big and you have to sort of squeeze them in there though.

I thought you liked Auricap's better than Panasonic's? Or is that in a different position?

Lucio

Different position. C8 is really the one absolutely critical cap to change. C1 and C2 aren't nearly as critical to change...on some material I heard no difference changing C1 and C2, on more transient stuff I think C1 C2 change I made sound slightly better/faster....it's hard to say though.

I'd agree, the change with C1 and C2 was very subtle.

Cool.

I'm sure it's all cumulative. A little here a little there... subtle adds up and can be the difference between high end and low end sound, right.

So Panasonic's for C1 and C2.
Black Gate for C6.
Auricap for C8.

What about C7? No one talks about changing that one.

Craig,
You remove C6 and C7. Do you prefer that over the Black Gate at C6? Obviously, it's more economic to remove C6 than to replace it and Dave T removes it also, so is it preferable to remove it?

The questions never end do they? Oops, that's another one.

Lucio

Lucio,

I'm actually experimenting with C6 and C7 right now and there effect on the sound. I'll let you know what I find.

Craig

Thanks, I appreciate that.

Lucio

Just thought I'd ask if there is really a problem with heating the other side of the tube even though it's not being used. I havn't removed anything from pin 5 and it sounds pretty good.

Is it just that the tube will wear out faster?

Hey Michael, have you tried putting foam in the bottom of your headbasket yet?

..yeah I did the foam thing. I'll be honest, I think it might be better. But, I really should have an identical version of the mic to a/b against. I feels like there's a bit more clarity with the foam in the bottom. And, as I've stated before, I haven't really focused on making a scientific study of testing things as I've gone along; there's no real valid testing, no "control" mic so to speak.

I can tell you this for sure, taking out the mesh radically changes the sound IMO. I kind of like the mics without the inner mesh myself.

quote:

Originally posted by honkyjonk:
Just thought I'd ask if there is really a problem with heating the other side of the tube even though it's not being used. I havn't removed anything from pin 5 and it sounds pretty good.

Is it just that the tube will wear out faster?

The main reason for removing the power from pin 5 is that it cuts the heat generation in half. There really is no way for the heat to leave the mic except through the case. This will add life to the tube and other electronics in the body. Also, there is a chance that it could induce what is known as cathode poisoning, which is the fact that the electrons are being boiled off the cathode and have nowhere to go, which could start breaking down the insides of the tube section as well as possibly affecting the other section.

...good info thanks Michael.

O.K. guys,

I've got a CEK-12 and Cinemag 2480 on the way to go into my Apex 460. The only thing left for me to do is order the capacitors. Originally I thought that I would just order one of each and try them, but once I added up the total there's just no way that I can afford to do that (same as many others I'm sure). I'm lucky to be able to get the capsule and tranny right now. That's why I'm hoping that the experience of someone here can help me (and many others ) out. I'm having a bit of trouble deciding on which size capacitor to choose for C8. I will be removing the cathode follower circuit.

Over the years of threads that I've read on this mod the choice for C8 has changed. Some stay with the original 1uf but usually complain about a lack of low end, while others have gone as high as 10uf with a bypass .01uf. I also imagine that the choice may be different depending on the capsule used and whether or not the cathode follower is kept. I also realize that this can be somewhat subjective to taste, but there has to be a starting point.

I want to get as close to a real C12 as I can in sound (don't we all). Some have grouped the C12 and the Elam 251 together as well as mentioning the C24. From the schematics I've read, the C12 used a 0.5uf, the C24 used a 1.5uf and the 251 used a 3.2uf. Many feel that C8 needs to be increased in size, but how far? I don't want a thin sounding mic.

So, to those who have a 460/1150 mic with a CEK-12 capsule and the Cinemag 2480 without the cathode follower, what size cap should go in C8?

Also, I have a TCM 1050 on the way that I want to lean towards a U47 (big surprise). I'm thinking of leaving the cathode follower in that one as I read that "With the cathode follower circuit the output will act more like the VF14 used in the U47 which has a lower output impedance."

So, would the choice for C8 be the same for the 1050?

I really appreciate everyones input. Thanks.

Lucio

Hey guys,

Okay, concerning the heater on the tube, can I just directly wire the yellow wire to pin 4 and bypass pin 5 or is it still going to go to pin 5?

i.e. Do I have to completely take pin 5 out of the circuit?

Lucio,

I'm using a 1uF auricap for C8. And so far it doesn't seem to be lacking in the low end. I havn't tried it on bass or kick drum though. So this is far from a tested review. Just a sort of feeling.

I have a CEK47 Peluso capsule in there. I tried a .68 uF C8 like MPCNYC was talking about and it did seem to have less low end. But I didn't give it any time to break in. I intend to go back and try it again. I sort of wish I'd ordered the CEK367 capsule because I'd rather not have the extra proximity effect. But this mic sounds great.

C8 is definitely the part that will make the biggest difference in sound. I'm not that convinced that the value makes the hugest difference within a range. I've tried .68 to 1.8 and the difference is not tremendous. Now this may have something to do with what kind of cap you put in there. I've settled on the Auricap, it justs sounds fastest and most natural to me.The mylars I've tried sound grainy and blurry to my ears in comparison. There's actually a forumula that if you know the impedence of the transformer and the cap value that you can figure out the actual frequency you are going to be rolling off at. I don't know it, a friend of mine explained it to me but it's a bit of a blur right now. In general I've stuck with 1.5uf. Seems to work fine with the 2480.

honkyjonk,

Yes, take pin 5 out of the circuit. Just remove the jumper from 4 to 5 so only 4 is wired up.

Yeh, I was looking at a U47 schematic and they use a 0.5uf, so technically the .68uf should be good, but other than you, I haven't read of anyone using a smaller value than 1uf. Now, as I said earlier, Dave Thomas used to use a 2.2uf paralleled with a .01uf, but I guess he settled on using a 1.5uf now.

What is a CEK47 Peluso? I talked with him yesterday and he said that the CEK-367 WAS his U47 capsule.

Lucio

Hmmm.

That's wierd that he would say that. What I have is a CEK347. MPCNYC has one in one of his mics too. They're not on his site, like the C-12 and 67 caps. You just have to ask him on the phone, which apparently you did. Very strange. Maybe there was a mis understanding or something because he doesn't seem like the kind of guy that would lie to you about it.

Anyway, I'm in the unfortunate position of having an early tcm 1050 with the tube soldered to the pcb. So I actually took a standard socket, bent, cut and made it fit into the pcb as best I could. Now I have a tube socket, but the problem with this is I have to now wrangle pin 5 of the socket out of the PCB and disconnect it because the jumper is actually part of the PCB.

Boy do we go to trouble to get a good sounding mic for cheap.

Okay,

I think I was right initially actually. Is the only place that pin 4 and 5 are connected on your guys' mics by some sort of jumper on the actual tube socket?

I'm actually not seeing leads on the board that are connecting 4 and 5. So, wierd, I've been only heating pin 5? Does that make sense that my mic is working?

I must have had a jumper on the original tube that I forgot about when I removed it. It doesn't look like my pin 4 is connecting with anything.

What should the multimeter be reading in the pin 4 and 5 sockets? 6V DC?

Nope.

Wrong. I'm getting 6V somehow to pin 4. I just don't see how it's getting there. Anyway, I guess digging out pin 5 is the only way.